1 00:00:14,890 --> 00:00:17,830 PETER SZOLOVITS: As David said, I've 2 00:00:17,830 --> 00:00:20,900 been at this for a long time. 3 00:00:20,900 --> 00:00:22,450 I am not a medical doctor. 4 00:00:22,450 --> 00:00:24,400 But I've probably learned enough medicine 5 00:00:24,400 --> 00:00:29,440 to be able to play one on television over the years. 6 00:00:29,440 --> 00:00:32,140 And actually, that's relevant to today's lecture 7 00:00:32,140 --> 00:00:34,450 because today's lecture is really 8 00:00:34,450 --> 00:00:38,210 trying to set the scene for you to say, well, 9 00:00:38,210 --> 00:00:40,360 what are the kinds of problems that doctors 10 00:00:40,360 --> 00:00:45,050 are interested in by looking at what is it that they do. 11 00:00:45,050 --> 00:00:45,820 OK. 12 00:00:45,820 --> 00:00:49,090 So that's our goal for today. 13 00:00:49,090 --> 00:00:50,590 So what we're going to do today is 14 00:00:50,590 --> 00:00:53,740 to talk about, in a very general way, what 15 00:00:53,740 --> 00:00:55,640 are the goals of health care. 16 00:00:55,640 --> 00:00:59,510 So how many of you are doctors? 17 00:00:59,510 --> 00:01:00,370 A couple. 18 00:01:00,370 --> 00:01:01,070 Great. 19 00:01:01,070 --> 00:01:01,600 OK. 20 00:01:01,600 --> 00:01:03,910 So fix me when I blow it. 21 00:01:03,910 --> 00:01:04,870 All right. 22 00:01:04,870 --> 00:01:09,220 Please feel free to interrupt. 23 00:01:09,220 --> 00:01:11,470 So that's going to be my first task. 24 00:01:11,470 --> 00:01:15,010 And then the second one is going to be 25 00:01:15,010 --> 00:01:18,940 what are the things that people actually do in order 26 00:01:18,940 --> 00:01:21,040 to try to achieve these goals. 27 00:01:21,040 --> 00:01:24,400 What is the practice of medicine like? 28 00:01:24,400 --> 00:01:27,430 What is the process that generates the data 29 00:01:27,430 --> 00:01:30,820 that we're going to be using to learn from? 30 00:01:30,820 --> 00:01:33,100 And then I can't resist talking a little bit 31 00:01:33,100 --> 00:01:36,850 about paying for health care at the end of the lecture 32 00:01:36,850 --> 00:01:40,030 because a lot of the problems that come up 33 00:01:40,030 --> 00:01:43,000 and a lot of the interest that people show 34 00:01:43,000 --> 00:01:46,360 in doing the kind of analysis we're talking about in fact 35 00:01:46,360 --> 00:01:48,260 is motivated by money. 36 00:01:48,260 --> 00:01:50,920 They want to be able to save money, or spend less 37 00:01:50,920 --> 00:01:52,700 money, or something like that. 38 00:01:52,700 --> 00:01:55,200 So it's important to know that. 39 00:01:55,200 --> 00:01:56,310 OK. 40 00:01:56,310 --> 00:01:58,610 Medicine's been around for a long time. 41 00:01:58,610 --> 00:02:03,290 I think from probably the earliest of recorded history, 42 00:02:03,290 --> 00:02:06,970 there are discussions of people wondering 43 00:02:06,970 --> 00:02:11,530 what the cause of disease is, how to cure it. 44 00:02:11,530 --> 00:02:15,100 They came up with some fairly cockamamie theories 45 00:02:15,100 --> 00:02:18,940 because they didn't have a lot of scientific, modern 46 00:02:18,940 --> 00:02:20,620 approaches to it. 47 00:02:20,620 --> 00:02:24,010 But for example, this is a photo on the left 48 00:02:24,010 --> 00:02:29,290 of a shaman I think from a Canadian Indian tribe who's 49 00:02:29,290 --> 00:02:33,100 working on the boy lying there who's sick. 50 00:02:33,100 --> 00:02:38,290 And this shaman would use his knowledge of experience 51 00:02:38,290 --> 00:02:40,720 that he'd had with other patients. 52 00:02:40,720 --> 00:02:45,040 They did know a lot about medicinal plants. 53 00:02:45,040 --> 00:02:49,120 They knew something about how to care for injuries and things 54 00:02:49,120 --> 00:02:50,150 like that. 55 00:02:50,150 --> 00:02:53,510 And so this was an effective form of health care. 56 00:02:53,510 --> 00:02:54,780 Not much record keeping. 57 00:02:54,780 --> 00:03:00,940 You don't see electronic medical records system in that scene. 58 00:03:00,940 --> 00:03:05,170 On the right is a modern shaman practicing at one 59 00:03:05,170 --> 00:03:07,870 of the New York area hospitals. 60 00:03:07,870 --> 00:03:10,330 And so there are traditional cultures 61 00:03:10,330 --> 00:03:14,920 in which that sort of hands on interaction with the healer 62 00:03:14,920 --> 00:03:17,350 is considered a very important part 63 00:03:17,350 --> 00:03:19,550 of the practice of medicine. 64 00:03:19,550 --> 00:03:23,440 And if you listen to futurist doctors talking about what 65 00:03:23,440 --> 00:03:27,850 medicine is likely to be like, they emphasize the fact 66 00:03:27,850 --> 00:03:31,000 that the role of a healer is not just 67 00:03:31,000 --> 00:03:36,250 to be a good automaton who figures out the right things 68 00:03:36,250 --> 00:03:40,630 but is to persuade a patient to trust 69 00:03:40,630 --> 00:03:44,230 them to do the things that he or she is suggesting 70 00:03:44,230 --> 00:03:46,040 to the patient. 71 00:03:46,040 --> 00:03:47,890 And there are a lot of placebo effects 72 00:03:47,890 --> 00:03:50,860 that we know from lots and lots of experiments 73 00:03:50,860 --> 00:03:53,350 that say that if you think you're going to get better, 74 00:03:53,350 --> 00:03:57,190 you are going to get better, on average. 75 00:03:57,190 --> 00:03:59,140 No guarantees. 76 00:03:59,140 --> 00:04:00,340 OK. 77 00:04:00,340 --> 00:04:04,460 Now modern medicine actually looks more like this. 78 00:04:04,460 --> 00:04:06,820 So this is an intensive care unit. 79 00:04:06,820 --> 00:04:09,250 And what you see is a patient who 80 00:04:09,250 --> 00:04:14,260 has got all kinds of electrical leads, and tubes, 81 00:04:14,260 --> 00:04:17,019 and things going into them and is surrounded 82 00:04:17,019 --> 00:04:19,990 by tons and tons of equipment which 83 00:04:19,990 --> 00:04:25,900 is monitoring him and perhaps keeping him alive. 84 00:04:25,900 --> 00:04:29,050 And so this is the high tech medicine 85 00:04:29,050 --> 00:04:31,690 that we think of as the contemporary version 86 00:04:31,690 --> 00:04:32,740 of clinical care. 87 00:04:35,250 --> 00:04:41,340 Well, you might say, OK, what does it mean to be healthy? 88 00:04:41,340 --> 00:04:41,840 Right. 89 00:04:41,840 --> 00:04:46,070 If the goal of medicine is to make people or keep 90 00:04:46,070 --> 00:04:48,350 people healthy, what is health? 91 00:04:48,350 --> 00:04:51,170 So we turn to the World Health Organization. 92 00:04:51,170 --> 00:04:54,290 And they have this lovely, very comprehensive notion 93 00:04:54,290 --> 00:04:56,240 of the definition of health. 94 00:04:56,240 --> 00:05:00,050 A state of complete physical, mental, and social well-being, 95 00:05:00,050 --> 00:05:03,420 not merely the absence of disease or infirmity. 96 00:05:03,420 --> 00:05:04,550 And then they categorize. 97 00:05:04,550 --> 00:05:07,190 This and they say, well, there's physical health, 98 00:05:07,190 --> 00:05:10,350 there's mental health, and there's social health. 99 00:05:10,350 --> 00:05:12,680 Social health is especially hard to measure. 100 00:05:12,680 --> 00:05:15,750 And I'll come back to that in a little while. 101 00:05:15,750 --> 00:05:20,280 So what's easiest to measure is how long people live. 102 00:05:20,280 --> 00:05:24,750 And so we've had data on survival analysis 103 00:05:24,750 --> 00:05:26,370 for a long time. 104 00:05:26,370 --> 00:05:28,950 And this is kind of shocking. 105 00:05:28,950 --> 00:05:35,700 If you look here, this lower curve is from around 1800. 106 00:05:35,700 --> 00:05:40,710 And what it shows you is that if you lived in India around 1800, 107 00:05:40,710 --> 00:05:45,560 your life expectancy was about 25 years. 108 00:05:45,560 --> 00:05:47,980 It's not very good. 109 00:05:47,980 --> 00:05:52,360 And if you lived in the richest countries, which in those days 110 00:05:52,360 --> 00:05:55,060 were typically European, in Belgium, 111 00:05:55,060 --> 00:05:59,850 your life expectancy was way up there at 40 years. 112 00:05:59,850 --> 00:06:00,440 Right. 113 00:06:00,440 --> 00:06:03,400 How many of you knew that? 114 00:06:03,400 --> 00:06:03,900 OK. 115 00:06:03,900 --> 00:06:04,590 Good. 116 00:06:04,590 --> 00:06:07,660 I didn't until I started looking at this. 117 00:06:07,660 --> 00:06:11,130 Now by 1950, which is not that long ago, it 118 00:06:11,130 --> 00:06:18,030 was like 69 years ago, in Norway your expectation 119 00:06:18,030 --> 00:06:20,730 was that you'd live into your early 70s, 120 00:06:20,730 --> 00:06:25,710 in the US that you would live into your late 60s on average. 121 00:06:25,710 --> 00:06:28,440 There was still a huge cliff where, 122 00:06:28,440 --> 00:06:33,120 if you lived in Bhutan, or Somalia, or something, 123 00:06:33,120 --> 00:06:34,830 you were still down around 30. 124 00:06:37,740 --> 00:06:42,330 Today, well in 2012, we're doing a lot better. 125 00:06:42,330 --> 00:06:45,630 And the thing that's striking is not only 126 00:06:45,630 --> 00:06:49,900 that the people who were doing well have gotten better 127 00:06:49,900 --> 00:06:52,650 but that a lot of the people who were doing very poorly 128 00:06:52,650 --> 00:06:54,330 have also gotten better. 129 00:06:54,330 --> 00:06:56,550 And so we're now up-- 130 00:06:56,550 --> 00:07:00,360 India, remember, was at 25 years of life expectancy 131 00:07:00,360 --> 00:07:02,760 and now it's in the high 60s. 132 00:07:02,760 --> 00:07:04,410 Now of course, these are averages. 133 00:07:04,410 --> 00:07:07,560 And so individuals vary a lot. 134 00:07:07,560 --> 00:07:09,250 But it's kind of interesting. 135 00:07:09,250 --> 00:07:12,180 So if you look at the numbers, you 136 00:07:12,180 --> 00:07:16,930 see that even on a shorter term, there are big changes. 137 00:07:16,930 --> 00:07:20,580 So for example, if you're a male living 138 00:07:20,580 --> 00:07:26,190 in Rwanda, which is among the worst places in terms of life 139 00:07:26,190 --> 00:07:29,120 expectancy, your life expectancy, 140 00:07:29,120 --> 00:07:33,400 if you were born today, is about 62 and 1/2 years. 141 00:07:33,400 --> 00:07:34,430 Right. 142 00:07:34,430 --> 00:07:38,970 If you were born in 2001, it was only 38 years. 143 00:07:38,970 --> 00:07:45,360 Now what was going on in Rwanda in 2001? 144 00:07:45,360 --> 00:07:45,990 Genocide. 145 00:07:45,990 --> 00:07:46,490 Yeah. 146 00:07:46,490 --> 00:07:47,760 They were killing each other. 147 00:07:47,760 --> 00:07:52,110 So that's sort of an exceptional situation. 148 00:07:52,110 --> 00:07:54,960 And that's gotten much better because they've 149 00:07:54,960 --> 00:07:58,260 stopped killing each other as genocidal attacks 150 00:07:58,260 --> 00:08:03,930 between the Hutu and Tutsi, I think, if I remember right. 151 00:08:03,930 --> 00:08:05,160 What about South Africa? 152 00:08:05,160 --> 00:08:15,640 What was going on in South Africa in 2001. 153 00:08:15,640 --> 00:08:16,910 I'm not sure I heard you. 154 00:08:16,910 --> 00:08:19,025 AUDIENCE: Failure to address the HIV crisis. 155 00:08:19,025 --> 00:08:19,900 PETER SZOLOVITS: Yes. 156 00:08:19,900 --> 00:08:23,530 The government at the time was claiming 157 00:08:23,530 --> 00:08:26,980 that HIV was not the cause of AIDS 158 00:08:26,980 --> 00:08:30,610 and therefore there was no point in controlling HIV infections 159 00:08:30,610 --> 00:08:34,070 because AIDS was caused by something else. 160 00:08:34,070 --> 00:08:36,260 Pretty crazy. 161 00:08:36,260 --> 00:08:37,390 So that was terrible. 162 00:08:37,390 --> 00:08:39,850 And they've gotten much better at it. 163 00:08:39,850 --> 00:08:44,810 So that's what you tend to see in a lot of African countries. 164 00:08:44,810 --> 00:08:48,130 And what you also see is that there has really been 165 00:08:48,130 --> 00:08:50,000 improvement everywhere. 166 00:08:50,000 --> 00:08:53,800 So in the US, we went from males expected 167 00:08:53,800 --> 00:08:59,500 to live 74 years to almost 78 years, so about a four year 168 00:08:59,500 --> 00:09:05,330 increase in life expectancy over a period of just 17 years. 169 00:09:05,330 --> 00:09:12,720 You women, by the way, are going to outlive us men, on average. 170 00:09:12,720 --> 00:09:16,156 There's some biological thing that seems to work that way. 171 00:09:16,156 --> 00:09:18,180 OK. 172 00:09:18,180 --> 00:09:21,870 So a typical way that people look 173 00:09:21,870 --> 00:09:25,800 at the survival of a population is 174 00:09:25,800 --> 00:09:28,920 to say, well, given a cohort of people 175 00:09:28,920 --> 00:09:32,820 born at some instant zero, what fraction of them 176 00:09:32,820 --> 00:09:37,090 are still alive after a certain period of time? 177 00:09:37,090 --> 00:09:39,620 And what you see is that, of course, 178 00:09:39,620 --> 00:09:42,240 2031 we haven't reached yet. 179 00:09:42,240 --> 00:09:44,820 And so these are projections based 180 00:09:44,820 --> 00:09:48,630 on sort of theoretical extrapolations of actual data. 181 00:09:48,630 --> 00:09:51,300 But the older data is real. 182 00:09:51,300 --> 00:09:57,150 And what you see is that from 1851 to, you know, 183 00:09:57,150 --> 00:10:02,370 2011 let's say, these numbers have gone way up. 184 00:10:02,370 --> 00:10:04,650 Now where have they gone up the most? 185 00:10:04,650 --> 00:10:09,540 Well, it used to be that childhood mortality was 186 00:10:09,540 --> 00:10:11,350 enormous. 187 00:10:11,350 --> 00:10:17,830 And so if you look at 1851, by age 10 about 30% of children 188 00:10:17,830 --> 00:10:19,930 had died. 189 00:10:19,930 --> 00:10:23,490 And so we've gotten a lot better at stopping that 190 00:10:23,490 --> 00:10:25,790 from happening. 191 00:10:25,790 --> 00:10:30,250 People also look at curves like this. 192 00:10:30,250 --> 00:10:34,440 So this is a distribution of death rates by age. 193 00:10:34,440 --> 00:10:37,620 This happens to be for Japan a few years ago. 194 00:10:37,620 --> 00:10:40,620 And again, females do better than males. 195 00:10:40,620 --> 00:10:45,850 The gold curve in the middle is the average of the two. 196 00:10:45,850 --> 00:10:49,770 And this is very typical of almost any country 197 00:10:49,770 --> 00:10:50,760 that you look at. 198 00:10:50,760 --> 00:10:55,290 The shape of this curve is pretty universal. 199 00:10:55,290 --> 00:10:56,970 So what does this say? 200 00:10:56,970 --> 00:11:02,390 It says that when you are born, there is a relatively high risk 201 00:11:02,390 --> 00:11:03,780 that you're going to die. 202 00:11:03,780 --> 00:11:07,820 So these are kids who have congenital abnormalities, 203 00:11:07,820 --> 00:11:13,460 have prenatal problems, have all kinds of difficulties. 204 00:11:13,460 --> 00:11:14,840 And they don't make it. 205 00:11:14,840 --> 00:11:19,370 So there's a fairly high death rate at birth. 206 00:11:19,370 --> 00:11:24,260 But once you make it to, I think, about two years old, 207 00:11:24,260 --> 00:11:31,920 the death rate is down to about one in 10,000 per year. 208 00:11:31,920 --> 00:11:32,760 Right. 209 00:11:32,760 --> 00:11:38,860 And then it stays quite low until you become a teenager. 210 00:11:38,860 --> 00:11:41,860 Now why might the death rate go up when you become a teenager? 211 00:11:45,300 --> 00:11:48,390 Well, suicide is the extreme example of that. 212 00:11:48,390 --> 00:11:51,900 But teenagers tend to be risk seeking 213 00:11:51,900 --> 00:11:54,270 rather than risk averse. 214 00:11:54,270 --> 00:11:56,070 You know, they start driving cars. 215 00:11:56,070 --> 00:11:59,610 They go skiing, skydiving, whatever 216 00:11:59,610 --> 00:12:01,960 it is that they're doing. 217 00:12:01,960 --> 00:12:04,050 And they start dying. 218 00:12:04,050 --> 00:12:07,890 But then if you make it to about 20, 219 00:12:07,890 --> 00:12:11,490 then there is a relatively flat region where by then 220 00:12:11,490 --> 00:12:14,730 you've developed enough sense to know what risks are worth 221 00:12:14,730 --> 00:12:17,350 taking and which ones aren't. 222 00:12:17,350 --> 00:12:23,190 And so it's relatively flat until about age 35 or 40 223 00:12:23,190 --> 00:12:28,230 at which point it starts inexorably rising. 224 00:12:28,230 --> 00:12:30,690 And of course, as you get older and older, 225 00:12:30,690 --> 00:12:33,450 the probability that you're going to die in the next year 226 00:12:33,450 --> 00:12:35,410 becomes higher and higher. 227 00:12:35,410 --> 00:12:35,910 Right. 228 00:12:35,910 --> 00:12:37,860 This is uncomfortable for somebody 229 00:12:37,860 --> 00:12:41,250 with my amount of gray hair. 230 00:12:41,250 --> 00:12:44,940 Now there is a peculiarity in Japan which people 231 00:12:44,940 --> 00:12:46,540 puzzled over for a while. 232 00:12:46,540 --> 00:12:52,210 And that is that weird dip up at age 106. 233 00:12:52,210 --> 00:12:56,030 So first of all, that's a very small number of people 234 00:12:56,030 --> 00:12:57,990 that that represents. 235 00:12:57,990 --> 00:13:01,240 And it turned out that it was fraud. 236 00:13:01,240 --> 00:13:04,740 So there were families who failed 237 00:13:04,740 --> 00:13:08,730 to report the death of their ancient grandmother 238 00:13:08,730 --> 00:13:11,400 or great-grandmother because they wanted 239 00:13:11,400 --> 00:13:13,500 to continue collecting social security 240 00:13:13,500 --> 00:13:16,050 payments from the government. 241 00:13:16,050 --> 00:13:17,175 So that's an artifact. 242 00:13:19,680 --> 00:13:20,180 OK. 243 00:13:25,200 --> 00:13:27,420 Now this is a serious problem which 244 00:13:27,420 --> 00:13:30,390 we're going to return to in a more technical way later 245 00:13:30,390 --> 00:13:34,420 in the semester, which is this problem of disparities. 246 00:13:34,420 --> 00:13:37,530 So if you look at, for example, the difference 247 00:13:37,530 --> 00:13:42,000 between white and black female life expectancy 248 00:13:42,000 --> 00:13:45,360 in the United States, you see that everybody's life 249 00:13:45,360 --> 00:13:48,720 expectancy, as we've shown, is going up gradually 250 00:13:48,720 --> 00:13:53,190 in this case from 1975 to 2015. 251 00:13:53,190 --> 00:13:57,840 But there continues to be a gap between black and white females 252 00:13:57,840 --> 00:14:00,600 and between black and white males 253 00:14:00,600 --> 00:14:05,910 where black patients are more likely to die 254 00:14:05,910 --> 00:14:12,120 or less likely to survive longer given the disparities that 255 00:14:12,120 --> 00:14:14,760 exist socioeconomically. 256 00:14:14,760 --> 00:14:16,560 Maybe medically. 257 00:14:16,560 --> 00:14:18,570 We don't know exactly. 258 00:14:18,570 --> 00:14:21,000 And then if you look at Hispanics, 259 00:14:21,000 --> 00:14:23,610 however, they do pretty well. 260 00:14:23,610 --> 00:14:26,940 So in 2015, you're actually a little bit 261 00:14:26,940 --> 00:14:30,000 better off to be Hispanic, either male or female, 262 00:14:30,000 --> 00:14:32,640 than you are to be either white or black. 263 00:14:32,640 --> 00:14:36,800 But it's still worse to be black than to be white or Hispanic. 264 00:14:36,800 --> 00:14:37,500 Right. 265 00:14:37,500 --> 00:14:40,680 So these are the kinds of facts that 266 00:14:40,680 --> 00:14:46,150 drive some of the issues in what we do in medical care. 267 00:14:46,150 --> 00:14:48,180 Now what do people die of? 268 00:14:48,180 --> 00:14:52,020 Well, about a quarter of them die of heart disease. 269 00:14:52,020 --> 00:14:54,510 And a little over a fifth of them die of cancer. 270 00:14:54,510 --> 00:14:59,100 This is USA data from 2014 so it's not completely up to date 271 00:14:59,100 --> 00:15:01,920 but hasn't changed that much. 272 00:15:01,920 --> 00:15:04,950 And then there's a decreasing number 273 00:15:04,950 --> 00:15:08,290 of deaths from various other causes. 274 00:15:08,290 --> 00:15:10,110 So heart disease, cancer, or chronic 275 00:15:10,110 --> 00:15:11,790 lower respiratory disease. 276 00:15:11,790 --> 00:15:14,640 So this is like COPD that's caused 277 00:15:14,640 --> 00:15:18,150 by smoking, stuff like that. 278 00:15:18,150 --> 00:15:22,110 Accidents account for about 5% of deaths. 279 00:15:22,110 --> 00:15:27,240 Stroke, cerebral vascular events, Alzheimer's disease, 280 00:15:27,240 --> 00:15:31,740 diabetes, influenza, pneumonia, kidney disease, suicide, 281 00:15:31,740 --> 00:15:34,920 and then everything else is about another quarter. 282 00:15:34,920 --> 00:15:36,340 OK. 283 00:15:36,340 --> 00:15:38,440 Now take a look at those. 284 00:15:38,440 --> 00:15:42,035 What kind of diseases are these, the biggies? 285 00:15:47,400 --> 00:15:47,900 Well. 286 00:15:47,900 --> 00:15:48,830 They're chronic. 287 00:15:48,830 --> 00:15:51,950 Most of them are chronic. 288 00:15:51,950 --> 00:15:54,910 They're also not infectious. 289 00:15:54,910 --> 00:15:58,010 But except for influenza and pneumonia, 290 00:15:58,010 --> 00:16:02,310 nothing else there is infectious as far as we know. 291 00:16:02,310 --> 00:16:05,840 I mean, yeah. 292 00:16:05,840 --> 00:16:10,460 That asterisk you should put after every statement 293 00:16:10,460 --> 00:16:13,040 about current medicine. 294 00:16:13,040 --> 00:16:16,820 So that's interesting, because if you wrote the same table 295 00:16:16,820 --> 00:16:20,730 back in 1850, you would find that a lot of people 296 00:16:20,730 --> 00:16:22,860 were dying of infections. 297 00:16:22,860 --> 00:16:24,810 And they weren't typically living 298 00:16:24,810 --> 00:16:28,170 long enough to develop these lovely chronic diseases 299 00:16:28,170 --> 00:16:30,540 of the aging. 300 00:16:30,540 --> 00:16:35,040 So there have been big changes there. 301 00:16:35,040 --> 00:16:37,860 Now the other thing that's worth looking at 302 00:16:37,860 --> 00:16:42,120 is, in addition to the reasons that people die, 303 00:16:42,120 --> 00:16:43,860 they start getting sicker. 304 00:16:43,860 --> 00:16:48,780 And they are getting sort of less value out of life 305 00:16:48,780 --> 00:16:52,670 because they're developing all these other conditions. 306 00:16:52,670 --> 00:16:58,310 So if you look at people over 65, about half of them 307 00:16:58,310 --> 00:17:02,970 have some form of arthritis. 308 00:17:02,970 --> 00:17:05,220 And about 40%-- yeah. 309 00:17:05,220 --> 00:17:09,329 About 40% have hypertension. 310 00:17:09,329 --> 00:17:12,750 By the way, if you have trouble with any 311 00:17:12,750 --> 00:17:15,839 of the medicalese words, just interrupt. 312 00:17:15,839 --> 00:17:18,569 Hypertension is high blood pressure. 313 00:17:18,569 --> 00:17:21,240 Hearing impairment. 314 00:17:21,240 --> 00:17:25,079 Me, I'm wearing a hearing aid on one side 315 00:17:25,079 --> 00:17:28,470 because my ears are going bad. 316 00:17:28,470 --> 00:17:30,640 Heart disease, about a quarter. 317 00:17:30,640 --> 00:17:33,840 Orthostatic impairment-- that means people who wobble 318 00:17:33,840 --> 00:17:37,440 because their sense of balance is not so good-- 319 00:17:37,440 --> 00:17:38,580 16%. 320 00:17:38,580 --> 00:17:43,530 Cataracts, chronic sinusitis, visual impairment, 321 00:17:43,530 --> 00:17:48,430 genitourinary problems, diabetes, et cetera. 322 00:17:48,430 --> 00:17:50,500 So these are all growing. 323 00:17:50,500 --> 00:17:53,400 Here's the list of the next 10. 324 00:17:53,400 --> 00:17:58,890 And varicose veins, hernia, hemorrhoids, psoriasis, 325 00:17:58,890 --> 00:18:02,430 hardening of the arteries, tinnitus, corns, calluses, 326 00:18:02,430 --> 00:18:06,450 constipation, hay fever, and cerebral vascular problems. 327 00:18:06,450 --> 00:18:07,410 All right. 328 00:18:07,410 --> 00:18:13,500 So people develop these by the time they're over 65. 329 00:18:13,500 --> 00:18:16,230 So one question we might ask is, well, 330 00:18:16,230 --> 00:18:18,670 what is the quality of life? 331 00:18:18,670 --> 00:18:22,740 So for example, a lot of the doctors 332 00:18:22,740 --> 00:18:26,280 that I started working with in the 1970s 333 00:18:26,280 --> 00:18:29,580 were great advocates of the application 334 00:18:29,580 --> 00:18:32,280 of decision analysis decision theory 335 00:18:32,280 --> 00:18:34,870 to making medical decisions. 336 00:18:34,870 --> 00:18:39,240 And so the problem is how do you evaluate an outcome? 337 00:18:39,240 --> 00:18:42,810 And they said, well, the way we evaluate an outcome is 338 00:18:42,810 --> 00:18:45,330 we look at your longevity. 339 00:18:45,330 --> 00:18:49,350 Obviously, the longer you live, the better typically. 340 00:18:49,350 --> 00:18:53,400 But we also look at your quality of life during that time. 341 00:18:53,400 --> 00:18:58,710 And we say that if you're confined to a wheelchair, 342 00:18:58,710 --> 00:19:01,320 let's say, your quality of life might not 343 00:19:01,320 --> 00:19:05,520 be as good as if you were able to run around, 344 00:19:05,520 --> 00:19:08,370 or if you're suffering from chronic pain, 345 00:19:08,370 --> 00:19:10,890 your quality of life might not be as good as 346 00:19:10,890 --> 00:19:13,930 if you were pain free. 347 00:19:13,930 --> 00:19:16,750 And so we came up with this model that says, 348 00:19:16,750 --> 00:19:23,730 well, the value of your life is essentially an integral 349 00:19:23,730 --> 00:19:26,760 from time zero to however long you're 350 00:19:26,760 --> 00:19:30,510 going to live of a function Q that 351 00:19:30,510 --> 00:19:34,920 says this is a measure of how good your quality of life 352 00:19:34,920 --> 00:19:39,420 is at that particular point in time and then some discount 353 00:19:39,420 --> 00:19:40,600 factor. 354 00:19:40,600 --> 00:19:41,100 Right. 355 00:19:41,100 --> 00:19:43,770 So what's the role of the discount factor? 356 00:19:43,770 --> 00:19:45,810 Well, it's just like in economics. 357 00:19:45,810 --> 00:19:50,790 If I offer you some horribly painful thing 358 00:19:50,790 --> 00:19:56,400 today versus 10 years from now, which are you going to choose? 359 00:19:56,400 --> 00:20:00,340 Most of us will say later. 360 00:20:00,340 --> 00:20:02,940 So that's what the discount factor does. 361 00:20:02,940 --> 00:20:06,780 Now who knows what the right discount rate is? 362 00:20:06,780 --> 00:20:09,600 So in some of their work, they were doing crazy things 363 00:20:09,600 --> 00:20:14,340 like taking the financial discount factors about bank 364 00:20:14,340 --> 00:20:16,470 interest rates and things like that 365 00:20:16,470 --> 00:20:18,810 and applying them to these health things 366 00:20:18,810 --> 00:20:21,690 just because they didn't have any better numbers to do. 367 00:20:21,690 --> 00:20:23,370 That seems a little suspicious. 368 00:20:23,370 --> 00:20:25,440 But nevertheless, methodologically, it's 369 00:20:25,440 --> 00:20:27,490 a way of doing it. 370 00:20:27,490 --> 00:20:28,200 OK. 371 00:20:28,200 --> 00:20:30,930 So how do you measure the quality of life? 372 00:20:30,930 --> 00:20:35,680 Well, there is this notion of the activities of daily living. 373 00:20:35,680 --> 00:20:38,000 So can you bathe and shower? 374 00:20:38,000 --> 00:20:41,940 Can you brush your teeth and groom your hair? 375 00:20:41,940 --> 00:20:42,900 Can you get dressed? 376 00:20:42,900 --> 00:20:46,170 Can you go to the toilet, clean yourself up? 377 00:20:46,170 --> 00:20:49,260 Are you able to walk, get in and out of bed, 378 00:20:49,260 --> 00:20:51,300 get in and out of a chair? 379 00:20:51,300 --> 00:20:53,530 Can you feed yourself? 380 00:20:53,530 --> 00:20:56,850 And then there are a bunch of instrumental factors, things 381 00:20:56,850 --> 00:20:59,700 like are you able to clean your house 382 00:20:59,700 --> 00:21:02,890 and can you manage your money and so on. 383 00:21:02,890 --> 00:21:06,150 So these are typically for older people. 384 00:21:06,150 --> 00:21:10,440 But they are ways of trying to quantify that quality of life 385 00:21:10,440 --> 00:21:15,070 by saying how many of these things are you able to do. 386 00:21:15,070 --> 00:21:17,040 And there are a lot of federal regulations, 387 00:21:17,040 --> 00:21:22,180 for example, that take advantage of quantification like this. 388 00:21:22,180 --> 00:21:26,760 So if you're asking to be put on some sort of disability 389 00:21:26,760 --> 00:21:30,900 where the government sends you a check to keep you alive, 390 00:21:30,900 --> 00:21:33,390 you have to demonstrate that you are 391 00:21:33,390 --> 00:21:35,550 at a certain point on the scale that's 392 00:21:35,550 --> 00:21:38,640 derived from these capabilities in order 393 00:21:38,640 --> 00:21:41,860 to justifiably get that. 394 00:21:41,860 --> 00:21:45,220 So occupational therapy is one of the things 395 00:21:45,220 --> 00:21:49,300 that people try to teach the elderly. 396 00:21:49,300 --> 00:21:54,250 My parents died in their late 80s and my dad was 90. 397 00:21:54,250 --> 00:21:59,270 And I remember when he would have some medical problem, 398 00:21:59,270 --> 00:22:01,360 then he would be put into the clutches 399 00:22:01,360 --> 00:22:05,230 of an occupational therapist who would try to make sure 400 00:22:05,230 --> 00:22:13,240 that he was able to communicate, and get around, and not 401 00:22:13,240 --> 00:22:17,620 fall for tricks where people wanted to get him to send all 402 00:22:17,620 --> 00:22:21,790 his money to them, or meal preparation 403 00:22:21,790 --> 00:22:22,940 and stuff like that. 404 00:22:22,940 --> 00:22:24,580 So these are sort of the-- 405 00:22:27,090 --> 00:22:29,160 occupational is a funny term for it, 406 00:22:29,160 --> 00:22:31,710 because this typically applies to people 407 00:22:31,710 --> 00:22:35,190 who are retired so it's not really an occupation. 408 00:22:35,190 --> 00:22:36,870 But it's the sort of things that you 409 00:22:36,870 --> 00:22:40,960 need to do in order to be able to have a decent life. 410 00:22:40,960 --> 00:22:44,450 Well, now there's an interesting valuation question. 411 00:22:44,450 --> 00:22:48,750 So if you look at the top right model, 412 00:22:48,750 --> 00:22:53,160 we actually don't have very good data on anything other 413 00:22:53,160 --> 00:22:54,240 than mortality. 414 00:22:54,240 --> 00:22:56,490 So mortality is who dies. 415 00:22:56,490 --> 00:22:59,850 So the blue curve there is the curve 416 00:22:59,850 --> 00:23:02,910 that you've seen before, which is, of a cohort, 417 00:23:02,910 --> 00:23:05,550 how many people are still alive after a certain number 418 00:23:05,550 --> 00:23:07,360 of years? 419 00:23:07,360 --> 00:23:11,730 The red curve is a morbidity curve 420 00:23:11,730 --> 00:23:17,700 which says how many of those people are still alive and have 421 00:23:17,700 --> 00:23:22,830 no sort of problematic chronic diseases. 422 00:23:22,830 --> 00:23:24,600 So they're not in constant pain. 423 00:23:24,600 --> 00:23:27,090 And they're not immobilized. 424 00:23:27,090 --> 00:23:31,710 And they're not unable to do the things that I just 425 00:23:31,710 --> 00:23:35,520 listed on the previous slides. 426 00:23:35,520 --> 00:23:39,870 And then disability is when you really 427 00:23:39,870 --> 00:23:43,500 become incapable of taking care of yourself. 428 00:23:43,500 --> 00:23:47,160 And it typically involves moving into an assisted living 429 00:23:47,160 --> 00:23:50,520 facility, or a nursing home, or something like that, which 430 00:23:50,520 --> 00:23:53,760 is kind of a nightmare for many people 431 00:23:53,760 --> 00:23:56,770 and also very expensive for society. 432 00:23:56,770 --> 00:24:00,270 So as I said, the blue curve there 433 00:24:00,270 --> 00:24:05,940 is based on actual data for American females in 1980. 434 00:24:05,940 --> 00:24:09,360 The red curve is a hypothetical curve 435 00:24:09,360 --> 00:24:14,760 where I just assumed that the rate of developing a morbidity 436 00:24:14,760 --> 00:24:18,220 is about twice the rate of dying. 437 00:24:18,220 --> 00:24:22,060 And the green curve I assumed that the rate 438 00:24:22,060 --> 00:24:27,040 of developing a disability is-- 439 00:24:27,040 --> 00:24:30,430 I can't remember-- I think three times as high as the rate 440 00:24:30,430 --> 00:24:32,180 of dying, something like that. 441 00:24:32,180 --> 00:24:35,290 So that's why those curves are lower. 442 00:24:35,290 --> 00:24:37,210 And they look approximately right. 443 00:24:37,210 --> 00:24:40,270 But we don't have good data on those. 444 00:24:40,270 --> 00:24:43,360 Now the question that you have to ask 445 00:24:43,360 --> 00:24:46,060 is, how do you want to change this? 446 00:24:46,060 --> 00:24:50,980 So for example, suppose that we kept the same situation. 447 00:24:50,980 --> 00:24:56,280 We reduced mortality to 20% of its actual rate. 448 00:24:56,280 --> 00:25:00,810 But we kept the disability and morbidity rates the same 449 00:25:00,810 --> 00:25:03,460 as they are on the top left. 450 00:25:03,460 --> 00:25:04,690 So what would that do? 451 00:25:04,690 --> 00:25:07,980 Well, what that would do is create a huge number 452 00:25:07,980 --> 00:25:18,000 of people who are disabled because they're 453 00:25:18,000 --> 00:25:21,000 going to live longer beyond the point 454 00:25:21,000 --> 00:25:24,620 where they're able to function fully. 455 00:25:24,620 --> 00:25:26,180 So this is-- yeah. 456 00:25:26,180 --> 00:25:28,450 AUDIENCE: Can I just ask, why does green not just 457 00:25:28,450 --> 00:25:29,223 mean healthy? 458 00:25:29,223 --> 00:25:30,140 To me, it just seems-- 459 00:25:30,140 --> 00:25:31,830 PETER SZOLOVITS: Green just means healthy. 460 00:25:31,830 --> 00:25:32,372 AUDIENCE: OK. 461 00:25:32,372 --> 00:25:33,183 It does. 462 00:25:33,183 --> 00:25:34,100 PETER SZOLOVITS: Yeah. 463 00:25:34,100 --> 00:25:37,910 So beyond green is what I meant is the morbidity curve. 464 00:25:37,910 --> 00:25:40,850 And beyond red is the disability curve. 465 00:25:40,850 --> 00:25:41,870 OK. 466 00:25:41,870 --> 00:25:44,630 I may have misspoken. 467 00:25:44,630 --> 00:25:47,520 So green is healthy. 468 00:25:47,520 --> 00:25:52,160 Red means suffering from some morbidity. 469 00:25:52,160 --> 00:25:55,680 And blue means disabled. 470 00:25:55,680 --> 00:26:00,000 So if we just extend life but we don't make it any better, 471 00:26:00,000 --> 00:26:03,470 then that's not a very attractive picture. 472 00:26:03,470 --> 00:26:06,710 So other possibilities are compression of morbidity. 473 00:26:06,710 --> 00:26:15,080 So for example, if we reduce the rate at which people get sick 474 00:26:15,080 --> 00:26:20,300 and die but we increase it-- 475 00:26:20,300 --> 00:26:23,600 we decrease it initially and then increase it 476 00:26:23,600 --> 00:26:27,260 so that, on average, people live about the same length of time 477 00:26:27,260 --> 00:26:31,580 that they now do, then we're going to have fewer people who 478 00:26:31,580 --> 00:26:33,830 are suffering from morbidity or who 479 00:26:33,830 --> 00:26:41,490 are disabled because you last doing well and then you die. 480 00:26:41,490 --> 00:26:44,960 So this is the wonderful one horse shay 481 00:26:44,960 --> 00:26:50,360 where everything falls apart at once, which, you know, frankly, 482 00:26:50,360 --> 00:26:52,790 as somebody who's a little closer to the end 483 00:26:52,790 --> 00:26:56,640 than you guys are, I wouldn't mind that kind of exit. 484 00:26:56,640 --> 00:26:57,830 Right. 485 00:26:57,830 --> 00:27:01,610 I don't want to be disabled for 20 years. 486 00:27:01,610 --> 00:27:03,560 I'd rather live a long time healthy 487 00:27:03,560 --> 00:27:05,710 and then drop dead at some point. 488 00:27:05,710 --> 00:27:06,210 OK. 489 00:27:09,650 --> 00:27:12,440 My dad used to say that he wanted to die 490 00:27:12,440 --> 00:27:15,080 by being hit by a meteor. 491 00:27:15,080 --> 00:27:15,800 Right. 492 00:27:15,800 --> 00:27:17,570 He wouldn't know it's coming. 493 00:27:17,570 --> 00:27:18,770 It's instant. 494 00:27:18,770 --> 00:27:20,420 No suffering, no pain. 495 00:27:20,420 --> 00:27:21,590 Perfect. 496 00:27:21,590 --> 00:27:25,760 He almost got it but not quite. 497 00:27:25,760 --> 00:27:26,620 OK. 498 00:27:26,620 --> 00:27:30,700 And then the final story is lifespan extension, 499 00:27:30,700 --> 00:27:38,640 which is where we simply lower the mortality rate and all 500 00:27:38,640 --> 00:27:40,870 the other rates in proportion. 501 00:27:40,870 --> 00:27:42,630 And what happens is that you start 502 00:27:42,630 --> 00:27:48,780 having healthy 107-year-olds and not so healthy 503 00:27:48,780 --> 00:27:53,580 120-year-olds in the population in larger numbers 504 00:27:53,580 --> 00:27:55,790 than we do now. 505 00:27:55,790 --> 00:27:57,400 OK. 506 00:27:57,400 --> 00:27:59,200 Social quality of life. 507 00:27:59,200 --> 00:28:01,102 That's a tough one. 508 00:28:01,102 --> 00:28:02,320 All right. 509 00:28:02,320 --> 00:28:05,310 So here's a naive theory. 510 00:28:05,310 --> 00:28:08,235 We take the quality of life of every person on the planet 511 00:28:08,235 --> 00:28:10,500 and we sum them up. 512 00:28:10,500 --> 00:28:13,240 And we say, OK, that's the social quality of life. 513 00:28:16,050 --> 00:28:19,090 Is that a good idea? 514 00:28:19,090 --> 00:28:19,980 Probably not. 515 00:28:19,980 --> 00:28:20,670 Right. 516 00:28:20,670 --> 00:28:22,440 For one thing, it would say that we 517 00:28:22,440 --> 00:28:26,730 ought to have as much population explosion as possible, 518 00:28:26,730 --> 00:28:30,340 because then we'd have more people to integrate over, 519 00:28:30,340 --> 00:28:34,140 which doesn't seem sensible. 520 00:28:34,140 --> 00:28:34,700 Right. 521 00:28:34,700 --> 00:28:39,060 Now obviously if we start packing the world so that it's 522 00:28:39,060 --> 00:28:41,910 super crowded, then the quality of life 523 00:28:41,910 --> 00:28:45,750 will go down eventually enough that adding more people 524 00:28:45,750 --> 00:28:48,120 is probably not optimal. 525 00:28:48,120 --> 00:28:54,240 But nevertheless, that doesn't seem like a real satisfying 526 00:28:54,240 --> 00:28:56,800 solution. 527 00:28:56,800 --> 00:28:58,370 How about less? 528 00:28:58,370 --> 00:29:00,840 It was popular about 10 years ago 529 00:29:00,840 --> 00:29:03,900 for people to write these sort of speculative books 530 00:29:03,900 --> 00:29:08,170 about how would the world look if half the people died. 531 00:29:08,170 --> 00:29:09,690 Right. 532 00:29:09,690 --> 00:29:11,250 Other than the trauma of the half 533 00:29:11,250 --> 00:29:14,430 the people dying, you know, they were 534 00:29:14,430 --> 00:29:20,250 proposing that this would be some wonderful sylvan 535 00:29:20,250 --> 00:29:25,440 sort of ideal old fashioned kind of world. 536 00:29:25,440 --> 00:29:27,060 I didn't buy that. 537 00:29:27,060 --> 00:29:29,220 And of course, we don't know of a good way 538 00:29:29,220 --> 00:29:32,160 to get there, although it is true 539 00:29:32,160 --> 00:29:34,560 that in at least developed countries, 540 00:29:34,560 --> 00:29:39,150 birth rates keep falling to the point where populations are 541 00:29:39,150 --> 00:29:41,910 worried about underpopulation. 542 00:29:41,910 --> 00:29:46,020 The Japanese, for example, have very strict immigration 543 00:29:46,020 --> 00:29:48,840 policies so you can't become Japanese 544 00:29:48,840 --> 00:29:51,270 if you're not born Japanese. 545 00:29:51,270 --> 00:29:53,820 And Japanese people aren't having enough kids 546 00:29:53,820 --> 00:29:55,630 to replace themselves. 547 00:29:55,630 --> 00:30:01,170 And so the natural population of Japan is falling. 548 00:30:01,170 --> 00:30:05,010 Italy is in the same quandary except that Italy 549 00:30:05,010 --> 00:30:08,640 has all these immigrants coming in and trying 550 00:30:08,640 --> 00:30:09,900 to become Italians. 551 00:30:09,900 --> 00:30:13,920 And of course, this leads to big political fights about who gets 552 00:30:13,920 --> 00:30:18,080 to be an Italian and who doesn't. 553 00:30:18,080 --> 00:30:19,880 And then, of course, there's the question 554 00:30:19,880 --> 00:30:23,390 of money, which as I say we'll return to later. 555 00:30:23,390 --> 00:30:26,830 Now one other important thing to consider 556 00:30:26,830 --> 00:30:32,860 is that because of the increase in life expectancy, 557 00:30:32,860 --> 00:30:37,180 there has been a big change in timescale in the way 558 00:30:37,180 --> 00:30:40,120 people think about medical care. 559 00:30:40,120 --> 00:30:46,060 So it used to be long, long ago in the shaman era, 560 00:30:46,060 --> 00:30:49,600 you wouldn't go to a shaman to say keep me healthy. 561 00:30:49,600 --> 00:30:53,170 You would go to a shaman saying, you know, I broke my arm, 562 00:30:53,170 --> 00:30:58,400 or I have this pain in my leg, or fix me somehow. 563 00:30:58,400 --> 00:31:03,140 And so things were focused on the notion of cure. 564 00:31:03,140 --> 00:31:06,960 And that was applicable to acute illnesses. 565 00:31:06,960 --> 00:31:09,750 But as we've gotten better at treating 566 00:31:09,750 --> 00:31:11,610 acute illnesses-- which, by the way, 567 00:31:11,610 --> 00:31:13,950 didn't happen all that long ago. 568 00:31:13,950 --> 00:31:16,410 I mean antibiotics were only invented 569 00:31:16,410 --> 00:31:18,480 in the early 20th century. 570 00:31:18,480 --> 00:31:22,050 And that made a huge difference in stopping people 571 00:31:22,050 --> 00:31:24,780 from dying of infections. 572 00:31:24,780 --> 00:31:28,140 So then it became more a matter of managing long term 573 00:31:28,140 --> 00:31:29,970 chronic illnesses. 574 00:31:29,970 --> 00:31:32,070 And that's pretty much where we are now. 575 00:31:32,070 --> 00:31:36,360 The medical world at the moment, most of the action 576 00:31:36,360 --> 00:31:39,210 is in trying to understand things like diabetes, 577 00:31:39,210 --> 00:31:41,850 and heart disease, and cancer, and things 578 00:31:41,850 --> 00:31:44,700 like that that develop over a long time. 579 00:31:44,700 --> 00:31:46,500 And they don't kill you instantly 580 00:31:46,500 --> 00:31:49,720 like infectious diseases did. 581 00:31:49,720 --> 00:31:53,370 But they produce a real burden. 582 00:31:53,370 --> 00:31:56,820 And then, of course, the next step that everybody expects 583 00:31:56,820 --> 00:32:00,210 is, well, how do we prevent disease? 584 00:32:00,210 --> 00:32:03,720 So how can we change your exposures? 585 00:32:03,720 --> 00:32:05,590 How can we change your motivation? 586 00:32:05,590 --> 00:32:06,930 How can we change your diet? 587 00:32:06,930 --> 00:32:10,650 How can we change whatever it is that we need to change? 588 00:32:10,650 --> 00:32:13,650 How can we change your genes to prevent you 589 00:32:13,650 --> 00:32:16,930 from developing these diseases in the first place? 590 00:32:16,930 --> 00:32:18,435 And that's sort of the future. 591 00:32:19,500 --> 00:32:21,090 OK. 592 00:32:21,090 --> 00:32:25,440 So that's about what medicine tries to do. 593 00:32:25,440 --> 00:32:26,820 But how does it do it? 594 00:32:26,820 --> 00:32:28,830 And so we're going to talk a little bit 595 00:32:28,830 --> 00:32:32,940 about the traditional tasks that are attributed to health care 596 00:32:32,940 --> 00:32:34,050 practice. 597 00:32:34,050 --> 00:32:38,320 So traditionally, people talk about diagnosis, prognosis, 598 00:32:38,320 --> 00:32:39,660 and therapy. 599 00:32:39,660 --> 00:32:42,390 So diagnosis-- I go to my doctor. 600 00:32:42,390 --> 00:32:45,210 I say, doc, I've got this horrible headache. 601 00:32:45,210 --> 00:32:47,460 I've had it for two weeks. 602 00:32:47,460 --> 00:32:50,340 What's wrong with me? 603 00:32:50,340 --> 00:32:56,446 And his job-- in my case, it happens to be a "he." 604 00:32:56,446 --> 00:33:00,545 His job is to come up with an answer. 605 00:33:00,545 --> 00:33:01,420 What's wrong with me? 606 00:33:04,340 --> 00:33:08,330 Prognosis is he's supposed to predict 607 00:33:08,330 --> 00:33:11,660 what's going to happen to me, at least if he doesn't 608 00:33:11,660 --> 00:33:14,130 do anything. 609 00:33:14,130 --> 00:33:16,770 So is this headache going to go away 610 00:33:16,770 --> 00:33:20,400 or is it going to turn out to be a brain tumor that 611 00:33:20,400 --> 00:33:25,350 will kill me, or is it going to be some amoeba that's living 612 00:33:25,350 --> 00:33:30,270 in my brain and eat my neurons? 613 00:33:30,270 --> 00:33:34,630 All kinds of horrible things are possible. 614 00:33:34,630 --> 00:33:37,470 So it's the prospect of recovery as anticipated 615 00:33:37,470 --> 00:33:42,450 from the usual course of disease or peculiarities of the case. 616 00:33:42,450 --> 00:33:46,570 And then therapy, of course, is what do you do about it. 617 00:33:46,570 --> 00:33:53,420 And prognosis is definitely informed by diagnosis, 618 00:33:53,420 --> 00:33:56,570 because if you don't know what's wrong with me, 619 00:33:56,570 --> 00:34:00,500 then it's much harder to predict what's going to happen to me. 620 00:34:00,500 --> 00:34:03,650 And if you can't predict what's going to happen to me, 621 00:34:03,650 --> 00:34:05,690 then it's much harder to figure out 622 00:34:05,690 --> 00:34:08,449 what to do to prevent that from happening 623 00:34:08,449 --> 00:34:11,670 or to encourage that to happen, right? 624 00:34:11,670 --> 00:34:15,570 So this is kind of a serial process. 625 00:34:15,570 --> 00:34:18,540 And the way I look at it is that there's 626 00:34:18,540 --> 00:34:23,159 a kind of cyclic process of care. 627 00:34:23,159 --> 00:34:27,360 And the process starts with an initial presentation. 628 00:34:27,360 --> 00:34:29,520 So I show up at my doctor's office 629 00:34:29,520 --> 00:34:31,949 and I complain about something. 630 00:34:31,949 --> 00:34:36,989 And if you ever listen to a doctor interacting 631 00:34:36,989 --> 00:34:39,940 with a patient, the first time the patient comes in, 632 00:34:39,940 --> 00:34:43,530 the first question is always, what brought you here? 633 00:34:43,530 --> 00:34:44,340 Right? 634 00:34:44,340 --> 00:34:47,400 And that's called the presenting complaint. 635 00:34:47,400 --> 00:34:51,659 So if I say, you know, my ankle hurts 636 00:34:51,659 --> 00:34:55,170 like hell, that's very different than if I say, 637 00:34:55,170 --> 00:34:58,350 I stopped being able to hear in my right ear, 638 00:34:58,350 --> 00:35:02,410 or I have this horrible skin rash on my arm, or whatever. 639 00:35:02,410 --> 00:35:05,990 And that's going to take me in very different directions. 640 00:35:05,990 --> 00:35:10,030 So then what happens is that the doctor examines you 641 00:35:10,030 --> 00:35:12,590 and generates a bunch of data. 642 00:35:12,590 --> 00:35:13,750 So these are measurements. 643 00:35:13,750 --> 00:35:16,810 And of course, it used to be that those measurements were 644 00:35:16,810 --> 00:35:18,850 based on observation. 645 00:35:18,850 --> 00:35:22,480 So there are very famous doctors from 100 years ago 646 00:35:22,480 --> 00:35:26,980 who were spectacularly good at being able to look at a patient 647 00:35:26,980 --> 00:35:28,910 and figure out what's wrong with them 648 00:35:28,910 --> 00:35:32,050 by being very astute observers-- 649 00:35:32,050 --> 00:35:36,070 the Sherlock Holmes kind of subtle, 650 00:35:36,070 --> 00:35:39,820 oh, I see that you have a cut on the inside of your shoe, 651 00:35:39,820 --> 00:35:43,030 which means you must have been going through brambles, 652 00:35:43,030 --> 00:35:44,620 and you know, whatever. 653 00:35:44,620 --> 00:35:48,040 I'm making up a Sherlock Holmes story here. 654 00:35:48,040 --> 00:35:50,290 So that generates data. 655 00:35:50,290 --> 00:35:53,110 And then we interpret that data to generate 656 00:35:53,110 --> 00:35:56,740 some kind of information or interpreted data 657 00:35:56,740 --> 00:35:58,960 about the patient. 658 00:35:58,960 --> 00:36:02,810 And based on that, we determine a diagnosis. 659 00:36:02,810 --> 00:36:05,020 Now, do we determine a diagnosis? 660 00:36:05,020 --> 00:36:05,800 Maybe not. 661 00:36:05,800 --> 00:36:08,870 Maybe we guess a diagnosis. 662 00:36:08,870 --> 00:36:12,550 One of the things I learned early on working in this field 663 00:36:12,550 --> 00:36:17,010 is that doctors are actually quite willing to make guesses, 664 00:36:17,010 --> 00:36:20,580 because it's so useful to believe that you understand 665 00:36:20,580 --> 00:36:22,530 what's going on. 666 00:36:22,530 --> 00:36:27,300 If you say, well, there's some probability distribution 667 00:36:27,300 --> 00:36:30,720 over a vast number of possible things, that 668 00:36:30,720 --> 00:36:34,470 doesn't give you very good guidance on what to do next. 669 00:36:34,470 --> 00:36:36,660 Whereas if you can say, oh, I think 670 00:36:36,660 --> 00:36:40,530 this patient is developing type 2 diabetes, 671 00:36:40,530 --> 00:36:44,640 then you're locked into a set of questions 672 00:36:44,640 --> 00:36:48,400 and a set of approaches that you might try. 673 00:36:48,400 --> 00:36:52,090 Now, when we come back to looking at machine learning, 674 00:36:52,090 --> 00:36:56,060 machines don't have the same limitations as people. 675 00:36:56,060 --> 00:36:59,590 And so for a machine to integrate over a vast number of 676 00:36:59,590 --> 00:37:04,960 possibilities is not difficult. But for a human cognition to do 677 00:37:04,960 --> 00:37:06,890 that is very hard. 678 00:37:06,890 --> 00:37:10,120 And so this is actually an important characteristic 679 00:37:10,120 --> 00:37:14,660 of the way doctors think about diagnostic reasoning. 680 00:37:14,660 --> 00:37:18,340 So then, having made a diagnosis or made a guess, 681 00:37:18,340 --> 00:37:20,680 they plan some kind of therapy. 682 00:37:20,680 --> 00:37:24,220 They apply that therapy, and then they wait awhile 683 00:37:24,220 --> 00:37:26,410 and they see what happened. 684 00:37:26,410 --> 00:37:31,210 So if your diagnosis led you to a choice of therapy, 685 00:37:31,210 --> 00:37:33,910 you gave that therapy to the patient and the patient 686 00:37:33,910 --> 00:37:36,340 got better, then you say, well, it must 687 00:37:36,340 --> 00:37:38,980 have been the right diagnosis. 688 00:37:38,980 --> 00:37:41,140 If the patient didn't get better, 689 00:37:41,140 --> 00:37:44,640 then you say, well, how did what happened to the patient 690 00:37:44,640 --> 00:37:49,570 differ from what I expected to happen to the patient? 691 00:37:49,570 --> 00:37:54,070 And that drives your revision of this whole process. 692 00:37:54,070 --> 00:37:57,090 So we again examine what happened 693 00:37:57,090 --> 00:37:58,950 as a result of the therapy. 694 00:37:58,950 --> 00:38:00,090 We gather more data. 695 00:38:00,090 --> 00:38:01,020 We interpret it. 696 00:38:01,020 --> 00:38:04,530 We come up with the revised diagnostic hypothesis. 697 00:38:04,530 --> 00:38:07,350 We come up with a revised therapeutic plan, 698 00:38:07,350 --> 00:38:11,040 and we keep going around the cycle. 699 00:38:11,040 --> 00:38:14,910 Now, that cycle happens very quickly 700 00:38:14,910 --> 00:38:18,360 if you're a hospitalized patient, because you're there 701 00:38:18,360 --> 00:38:19,110 all the time. 702 00:38:19,110 --> 00:38:20,070 You're available. 703 00:38:20,070 --> 00:38:23,170 They're trying to do things to you constantly. 704 00:38:23,170 --> 00:38:28,600 And so this cycle happens on the order of hours or a day, 705 00:38:28,600 --> 00:38:30,570 whereas if you were an outpatient, then 706 00:38:30,570 --> 00:38:32,940 you're not dealing with some urgent problem. 707 00:38:32,940 --> 00:38:36,060 It may happen over a much slower period. 708 00:38:36,060 --> 00:38:39,190 It may be that your doctor says, well, 709 00:38:39,190 --> 00:38:40,860 we're going to adjust your drug dose 710 00:38:40,860 --> 00:38:44,400 and see if that helps bring down your cholesterol, 711 00:38:44,400 --> 00:38:48,750 or manage your pain, or whatever it is that he's trying to do. 712 00:38:48,750 --> 00:38:51,060 Or worse yet, we're going to try to convince 713 00:38:51,060 --> 00:38:55,050 you to eat more healthy food, and six months later we'll 714 00:38:55,050 --> 00:38:58,500 see if your hemoglobin A1C came down, that you're 715 00:38:58,500 --> 00:39:02,310 less close to being diabetic. 716 00:39:02,310 --> 00:39:04,560 So the time scale is very different. 717 00:39:04,560 --> 00:39:11,220 But that process of continually reinterpreting things 718 00:39:11,220 --> 00:39:15,280 is a really critical feature, I think, of all of medical care. 719 00:39:15,280 --> 00:39:20,640 And if you look back, Alan Turing actually 720 00:39:20,640 --> 00:39:25,260 talked, in the early 1950s, about health care 721 00:39:25,260 --> 00:39:28,440 as being one of the interesting application areas 722 00:39:28,440 --> 00:39:31,980 of artificial intelligence. 723 00:39:31,980 --> 00:39:32,550 Why? 724 00:39:32,550 --> 00:39:35,130 Well, because it was an important topic. 725 00:39:35,130 --> 00:39:37,530 And he had the vision that says, as we 726 00:39:37,530 --> 00:39:40,510 start getting more data about health care, 727 00:39:40,510 --> 00:39:42,990 we're going to be able to build the kinds of models 728 00:39:42,990 --> 00:39:47,670 that we're going to be talking about in this class. 729 00:39:47,670 --> 00:39:53,803 But a lot of the early work took a kind of one-shot approach. 730 00:39:53,803 --> 00:39:55,470 So they said, well, we're going to solve 731 00:39:55,470 --> 00:39:57,520 the diagnostic problem. 732 00:39:57,520 --> 00:40:00,570 So we're going to take a snapshot of a patient, all 733 00:40:00,570 --> 00:40:02,340 their data at a particular moment. 734 00:40:02,340 --> 00:40:04,530 We're going to feed it into an algorithm. 735 00:40:04,530 --> 00:40:06,660 It'll come up with a diagnosis. 736 00:40:06,660 --> 00:40:09,490 We're done. 737 00:40:09,490 --> 00:40:13,060 And that wasn't very useful, because it 738 00:40:13,060 --> 00:40:17,650 didn't obey the cyclic nature of the process of providing health 739 00:40:17,650 --> 00:40:18,730 care. 740 00:40:18,730 --> 00:40:22,480 And so this was a revolution that started, really, 741 00:40:22,480 --> 00:40:26,440 around the 1980s when people realized that you have 742 00:40:26,440 --> 00:40:29,620 to be in it for the long-run and not for sort 743 00:40:29,620 --> 00:40:31,550 of single interactions. 744 00:40:31,550 --> 00:40:37,640 OK, well, this is just some definitions 745 00:40:37,640 --> 00:40:40,260 of these care processes. 746 00:40:40,260 --> 00:40:46,580 So here I've listed some ideas that came from a 1976 paper 747 00:40:46,580 --> 00:40:50,780 by several of my colleagues, who said, well, 748 00:40:50,780 --> 00:40:53,750 here's a cognitive theory of diagnosis. 749 00:40:53,750 --> 00:40:59,240 From the initial complaints, guess a suitable hypothesis. 750 00:40:59,240 --> 00:41:01,850 Use the current active hypotheses 751 00:41:01,850 --> 00:41:03,710 to guide questioning-- 752 00:41:03,710 --> 00:41:08,430 so to order more tests, to ask questions of the patient. 753 00:41:08,430 --> 00:41:11,460 And it's the failure to satisfy expectations 754 00:41:11,460 --> 00:41:15,750 that's the strongest clue to how to develop a better hypothesis. 755 00:41:18,540 --> 00:41:22,140 And then the hypotheses could be in an activated, 756 00:41:22,140 --> 00:41:25,740 deactivated, confirmed, or rejected state. 757 00:41:25,740 --> 00:41:27,930 They actually built a computer program 758 00:41:27,930 --> 00:41:32,460 that implemented this theory of diagnostic reasoning. 759 00:41:32,460 --> 00:41:38,540 And these rules, essentially, about whether to activate, 760 00:41:38,540 --> 00:41:41,370 deactivate, confirm, or reject something 761 00:41:41,370 --> 00:41:44,340 could be based both on logical criteria 762 00:41:44,340 --> 00:41:49,210 and on a kind of very bad probabilistic model. 763 00:41:49,210 --> 00:41:52,230 So it was very bad, because what they really 764 00:41:52,230 --> 00:41:54,510 needed was Bayesian networks. 765 00:41:54,510 --> 00:41:59,280 And those were about a decade in the future at that point. 766 00:41:59,280 --> 00:42:04,920 So they and every other system built in the 1970s 767 00:42:04,920 --> 00:42:07,320 had really horrible probabilistic models, 768 00:42:07,320 --> 00:42:10,570 because we didn't understand how to do it correctly. 769 00:42:10,570 --> 00:42:13,080 Now, what's interesting is somebody noticed 770 00:42:13,080 --> 00:42:16,110 that if you strip away the medicine from this, 771 00:42:16,110 --> 00:42:20,760 this is kind of like the scientific method, right? 772 00:42:20,760 --> 00:42:23,340 If you're trying to understand something, 773 00:42:23,340 --> 00:42:24,810 you form a hypothesis. 774 00:42:24,810 --> 00:42:26,670 You perform an experiment. 775 00:42:26,670 --> 00:42:30,330 If the experiment is consistent with your expectations, 776 00:42:30,330 --> 00:42:33,420 then you go on and you've gotten a little bit more confident 777 00:42:33,420 --> 00:42:35,010 in your hypothesis. 778 00:42:35,010 --> 00:42:36,960 If your experiment is inconsistent 779 00:42:36,960 --> 00:42:40,740 with your expectations, then you have to change your theory, 780 00:42:40,740 --> 00:42:42,510 change your hypothesis. 781 00:42:42,510 --> 00:42:46,140 You go back and gather more data, and then keep doing this 782 00:42:46,140 --> 00:42:48,180 until you're satisfied that you've come up 783 00:42:48,180 --> 00:42:50,290 with an adequate theory. 784 00:42:50,290 --> 00:42:52,890 So this was a surprise to doctors, 785 00:42:52,890 --> 00:42:55,410 because they thought of themselves more 786 00:42:55,410 --> 00:42:58,090 as artists than as scientists. 787 00:42:58,090 --> 00:43:00,480 But in a way, they act like scientists, 788 00:43:00,480 --> 00:43:02,620 which is kind of cool. 789 00:43:02,620 --> 00:43:06,390 All right, this doesn't stop with caring 790 00:43:06,390 --> 00:43:08,310 for a single patient. 791 00:43:08,310 --> 00:43:12,510 So we have all these meta-level processes about the acquisition 792 00:43:12,510 --> 00:43:15,840 and the application of knowledge about education, 793 00:43:15,840 --> 00:43:20,280 quality control and process improvement, cost containment, 794 00:43:20,280 --> 00:43:22,260 and developing references. 795 00:43:22,260 --> 00:43:25,320 So this is a picture from David Margulies, 796 00:43:25,320 --> 00:43:28,950 who was chief information officer at Children's Hospital 797 00:43:28,950 --> 00:43:29,820 here. 798 00:43:29,820 --> 00:43:34,500 And the cycle that I described is the one right here. 799 00:43:34,500 --> 00:43:38,160 This is the care team taking care of a patient. 800 00:43:38,160 --> 00:43:42,420 But of course at some point, that patient is discharged. 801 00:43:42,420 --> 00:43:46,080 And then they're in community care and self-care, 802 00:43:46,080 --> 00:43:49,230 and then maybe they're in some sort of active health status 803 00:43:49,230 --> 00:43:51,480 management. 804 00:43:51,480 --> 00:43:54,390 And then if that goes badly, then there's 805 00:43:54,390 --> 00:43:58,080 some episode where they reconnect to the health care 806 00:43:58,080 --> 00:43:59,170 system. 807 00:43:59,170 --> 00:44:01,890 They get authorized to come back. 808 00:44:01,890 --> 00:44:06,310 They get scheduled for a visit, and they're back in the cycle. 809 00:44:06,310 --> 00:44:10,590 And so the process of care involves 810 00:44:10,590 --> 00:44:13,350 people going to the hospital, getting taken 811 00:44:13,350 --> 00:44:17,040 care of, they get better, they get discharged, 812 00:44:17,040 --> 00:44:19,350 they live their lives for a while. 813 00:44:19,350 --> 00:44:21,060 Maybe they get sick again. 814 00:44:21,060 --> 00:44:21,960 They come back. 815 00:44:21,960 --> 00:44:26,910 And so there's this larger cycle around that issue. 816 00:44:26,910 --> 00:44:31,590 And then around that are all kinds of things about health 817 00:44:31,590 --> 00:44:36,660 plan design and membership and what coverage 818 00:44:36,660 --> 00:44:38,400 you have and so on. 819 00:44:38,400 --> 00:44:41,880 And then I would add one more idea, which 820 00:44:41,880 --> 00:44:45,690 is that if you have a system like this, 821 00:44:45,690 --> 00:44:50,340 you actually want to study, at the next meta-level, 822 00:44:50,340 --> 00:44:53,980 that system, make observations about it, 823 00:44:53,980 --> 00:44:57,360 analyze it, model it, plan some improvements, 824 00:44:57,360 --> 00:45:02,310 and then intervene in the system and observe how it's working 825 00:45:02,310 --> 00:45:05,340 and try to make it better. 826 00:45:05,340 --> 00:45:11,340 So in terms of tasks that are important for us in this class, 827 00:45:11,340 --> 00:45:17,490 this class of tasks is central, because one 828 00:45:17,490 --> 00:45:20,100 of the things we're trying to do is 829 00:45:20,100 --> 00:45:22,020 to look at the way health care works 830 00:45:22,020 --> 00:45:24,240 and to figure out how to make it better 831 00:45:24,240 --> 00:45:26,520 by examining its operation. 832 00:45:26,520 --> 00:45:29,310 And that can be done at any of these three levels. 833 00:45:29,310 --> 00:45:32,940 It can be done in the more acute phase, where 834 00:45:32,940 --> 00:45:34,440 we're dealing with somebody who's 835 00:45:34,440 --> 00:45:36,090 in the middle of an illness. 836 00:45:36,090 --> 00:45:39,840 It can be done at the larger phase of somebody who's 837 00:45:39,840 --> 00:45:42,630 going through the cycle of being well for a while 838 00:45:42,630 --> 00:45:46,080 and then being sick, and then being well again and being sick 839 00:45:46,080 --> 00:45:46,950 again. 840 00:45:46,950 --> 00:45:50,980 And it can be in terms of the system itself, 841 00:45:50,980 --> 00:45:54,570 of how do you design a health care system that works better 842 00:45:54,570 --> 00:45:56,290 for the population? 843 00:45:56,290 --> 00:45:59,100 So this notion of a learning health care system 844 00:45:59,100 --> 00:46:01,290 is now a journal. 845 00:46:01,290 --> 00:46:05,790 So in 2017, Chuck Friedman at the University of Michigan 846 00:46:05,790 --> 00:46:08,130 started this new journal. 847 00:46:08,130 --> 00:46:13,350 And it's full of articles about this third level 848 00:46:13,350 --> 00:46:17,790 of external cycle. 849 00:46:17,790 --> 00:46:20,960 So how does the health care system learn? 850 00:46:20,960 --> 00:46:23,900 Well, I'll tell you an anecdote. 851 00:46:23,900 --> 00:46:30,900 In the mid-1980s, I was teaching an AI expert systems course. 852 00:46:30,900 --> 00:46:33,440 And I had just come back from a conference 853 00:46:33,440 --> 00:46:35,960 of medical informatics people, where 854 00:46:35,960 --> 00:46:39,200 they were talking about this great new idea called 855 00:46:39,200 --> 00:46:42,090 evidence-based medicine. 856 00:46:42,090 --> 00:46:45,600 And I remember mentioning this to a bunch of MIT engineering 857 00:46:45,600 --> 00:46:46,260 students. 858 00:46:46,260 --> 00:46:50,900 And one of them raised his hand and said, as opposed to what? 859 00:46:50,900 --> 00:46:52,160 Right? 860 00:46:52,160 --> 00:46:54,540 I mean, to an engineer, it's obvious 861 00:46:54,540 --> 00:46:58,260 that evidence is the basis on which you analyze 862 00:46:58,260 --> 00:47:00,460 things and make things better. 863 00:47:00,460 --> 00:47:03,120 But it wasn't obvious to doctors. 864 00:47:03,120 --> 00:47:06,820 And so this was almost a revolutionary change. 865 00:47:06,820 --> 00:47:09,120 And the idea that they fostered was 866 00:47:09,120 --> 00:47:13,510 the idea of the randomized controlled clinical trial. 867 00:47:13,510 --> 00:47:17,070 So I'm going to sketch what that looks like. 868 00:47:17,070 --> 00:47:18,750 Of course, there are many variations. 869 00:47:18,750 --> 00:47:22,530 But suppose that I'm one of the drug companies around Kendall 870 00:47:22,530 --> 00:47:25,830 Square, and I come up with a new drug 871 00:47:25,830 --> 00:47:28,770 and I want to prove that it's more effective for condition 872 00:47:28,770 --> 00:47:32,540 X than some existing drug B. 873 00:47:32,540 --> 00:47:34,130 So what do I do? 874 00:47:34,130 --> 00:47:38,060 I find some patients who are suffering from X 875 00:47:38,060 --> 00:47:41,000 and I try very hard to find patients who are not 876 00:47:41,000 --> 00:47:43,220 suffering from anything else. 877 00:47:43,220 --> 00:47:46,290 I want the purest case possible. 878 00:47:46,290 --> 00:47:49,190 I then go to my statisticians and I 879 00:47:49,190 --> 00:47:52,310 say, let's design an experiment where 880 00:47:52,310 --> 00:47:55,550 we're going to collect a standard set of data 881 00:47:55,550 --> 00:47:57,880 about all these patients. 882 00:47:57,880 --> 00:48:02,500 And then we're going to give some of Drug A and some of them 883 00:48:02,500 --> 00:48:06,280 Drug B, and we'll see which of them do better. 884 00:48:06,280 --> 00:48:10,180 And we'll pre-define what we mean by do better. 885 00:48:10,180 --> 00:48:13,210 So like, not dying is considered doing better, 886 00:48:13,210 --> 00:48:17,970 or not suffering some bad thing that people are suffering from 887 00:48:17,970 --> 00:48:21,830 is considered doing better. 888 00:48:21,830 --> 00:48:25,240 And then the statisticians also will 889 00:48:25,240 --> 00:48:30,370 tell me, given that you expect Drug A to be, 890 00:48:30,370 --> 00:48:33,820 let's say, 10% better than Drug B, 891 00:48:33,820 --> 00:48:37,480 how many patients do you have to enroll in this trial 892 00:48:37,480 --> 00:48:40,990 in order to be likely to get a statistically significant 893 00:48:40,990 --> 00:48:43,690 answer to that question? 894 00:48:43,690 --> 00:48:45,370 And then they do it. 895 00:48:45,370 --> 00:48:48,250 The statisticians analyze the data. 896 00:48:48,250 --> 00:48:51,610 Hopefully you've gotten p less than 0.05. 897 00:48:51,610 --> 00:48:53,680 You go to the Food and Drug Administration 898 00:48:53,680 --> 00:48:57,670 and say, give me permission to market this drug as the hottest 899 00:48:57,670 --> 00:49:01,150 new cure for something or other, and then you 900 00:49:01,150 --> 00:49:02,990 make billions of dollars. 901 00:49:02,990 --> 00:49:03,490 Right? 902 00:49:03,490 --> 00:49:07,490 This is the standard way that pharma works. 903 00:49:07,490 --> 00:49:09,770 Now, there are some problems. 904 00:49:09,770 --> 00:49:16,080 So most of the cases to which the results 905 00:49:16,080 --> 00:49:19,620 of a trial like this are applied wouldn't have 906 00:49:19,620 --> 00:49:23,530 qualified to be in the trial. 907 00:49:23,530 --> 00:49:29,150 For example, we talked about morbidities, about 908 00:49:29,150 --> 00:49:31,860 the chronic problems that people have. 909 00:49:31,860 --> 00:49:34,140 Well, if you're dealing with one disease, 910 00:49:34,140 --> 00:49:37,620 you want to make sure that those populations you're dealing with 911 00:49:37,620 --> 00:49:39,880 don't have any of these other diseases. 912 00:49:39,880 --> 00:49:42,430 But in the real world, people do. 913 00:49:42,430 --> 00:49:44,430 And so we've never actually measured 914 00:49:44,430 --> 00:49:47,820 what happens to those people if you give them this drug 915 00:49:47,820 --> 00:49:52,020 and they have these comorbidities. 916 00:49:52,020 --> 00:49:54,420 The other problem is that the drug company 917 00:49:54,420 --> 00:49:57,450 wants to start making these billions of dollars 918 00:49:57,450 --> 00:49:59,650 as soon as possible. 919 00:49:59,650 --> 00:50:03,780 And so they want the trial to be as short as possible. 920 00:50:03,780 --> 00:50:06,900 And they want it to be as small a sample as they 921 00:50:06,900 --> 00:50:11,320 need to get that 0.05 statistical significance. 922 00:50:11,320 --> 00:50:17,410 So these are all problematic, and they lead to real problems. 923 00:50:17,410 --> 00:50:19,560 So I didn't bring any examples, but there 924 00:50:19,560 --> 00:50:23,400 are plenty of stories where the FDA has approved 925 00:50:23,400 --> 00:50:25,770 some drug on this basis, and then 926 00:50:25,770 --> 00:50:30,450 later they discovered that although the drug works well 927 00:50:30,450 --> 00:50:32,910 in the short-term, it has horrible side 928 00:50:32,910 --> 00:50:36,600 effects in the long-term, or that it has interactions 929 00:50:36,600 --> 00:50:39,960 with other diseases where it doesn't work effectively 930 00:50:39,960 --> 00:50:45,600 for people except for these pure cases that it was tested on. 931 00:50:45,600 --> 00:50:50,520 So the other idea, the competing idea is to say, let's 932 00:50:50,520 --> 00:50:54,120 build this learning health care system in which progress 933 00:50:54,120 --> 00:50:55,650 in science, informatics-- 934 00:50:55,650 --> 00:50:58,680 whatever-- generates new knowledge 935 00:50:58,680 --> 00:51:02,820 as an ongoing natural byproduct of the care experience 936 00:51:02,820 --> 00:51:07,200 and we seamlessly refine and deliver best practices 937 00:51:07,200 --> 00:51:10,350 for continuous improvement in health and health care. 938 00:51:10,350 --> 00:51:13,170 Wonderful words from the Institute of Medicine, 939 00:51:13,170 --> 00:51:17,760 now called the National Academy of Medicine. 940 00:51:17,760 --> 00:51:19,870 But it's hard to do this. 941 00:51:19,870 --> 00:51:21,660 And the reason it's hard to do this 942 00:51:21,660 --> 00:51:26,880 is mainly for a very profound underlying reason, 943 00:51:26,880 --> 00:51:29,700 which is that people are not treated 944 00:51:29,700 --> 00:51:32,280 by experimental protocols. 945 00:51:32,280 --> 00:51:35,520 So it's very important in that sketch 946 00:51:35,520 --> 00:51:39,120 that I gave you of the Drug A versus Drug B 947 00:51:39,120 --> 00:51:43,950 that there is a randomization step where I flip a coin 948 00:51:43,950 --> 00:51:47,430 to decide which drug any particular individual is going 949 00:51:47,430 --> 00:51:49,230 to get. 950 00:51:49,230 --> 00:51:55,140 If I allow that decision to be biased by my expectations 951 00:51:55,140 --> 00:51:57,990 or by something else I know about the patient, 952 00:51:57,990 --> 00:52:01,320 then I'm no longer doing a fair trial. 953 00:52:01,320 --> 00:52:03,600 And of course, when I collect data 954 00:52:03,600 --> 00:52:06,840 about how actual patients are being treated, 955 00:52:06,840 --> 00:52:10,020 they're being treated according to what their doctors think 956 00:52:10,020 --> 00:52:14,360 is best for them, and so there is no randomization. 957 00:52:14,360 --> 00:52:17,310 I mean, if I went to Mass General and said, could you 958 00:52:17,310 --> 00:52:19,470 guys please treat everybody randomly 959 00:52:19,470 --> 00:52:23,010 so that we collect really good data, 960 00:52:23,010 --> 00:52:27,310 they would throw me out properly. 961 00:52:27,310 --> 00:52:32,520 OK, so we also need a whole lot of technical infrastructure. 962 00:52:32,520 --> 00:52:35,910 We need to capture all kinds of novel data sources, which we'll 963 00:52:35,910 --> 00:52:38,830 talk about in the next lecture. 964 00:52:38,830 --> 00:52:40,920 And then we need a technical infrastructure 965 00:52:40,920 --> 00:52:42,780 for truly big data. 966 00:52:42,780 --> 00:52:51,230 So just for example, Dana Farber started about five years ago-- 967 00:52:51,230 --> 00:52:52,370 it's a cancer hospital. 968 00:52:52,370 --> 00:52:54,980 And so for every solid tumor, they 969 00:52:54,980 --> 00:52:58,670 would take samples of the tumor and genotype it-- 970 00:52:58,670 --> 00:53:02,940 multiple samples, because tumors are not uniform. 971 00:53:02,940 --> 00:53:06,230 So just storing that stuff is a technical challenge, 972 00:53:06,230 --> 00:53:08,960 and being able to come up with it. 973 00:53:08,960 --> 00:53:16,250 You've got three gigabases, so about over a gigabyte of data-- 974 00:53:16,250 --> 00:53:19,060 from each sample, from each tumor, 975 00:53:19,060 --> 00:53:23,420 times all the people who come in and have this test. 976 00:53:23,420 --> 00:53:26,720 So you buy some big disk drives or you farm 977 00:53:26,720 --> 00:53:28,620 it out to Google or something. 978 00:53:28,620 --> 00:53:30,830 But then you need to organize it in some way 979 00:53:30,830 --> 00:53:36,170 so that it's usefully easy to find that data. 980 00:53:36,170 --> 00:53:40,520 So today's technique, today's prejudice 981 00:53:40,520 --> 00:53:44,870 is what I call the meat grinder story, which 982 00:53:44,870 --> 00:53:47,220 is you take medical records, genetic data, 983 00:53:47,220 --> 00:53:50,180 environmental data, data from wearables, 984 00:53:50,180 --> 00:53:53,210 you put them into an old-fashioned meat grinder, 985 00:53:53,210 --> 00:53:56,780 and out come bits, which you store on a disk. 986 00:53:56,780 --> 00:53:58,880 And then you have all the data from which 987 00:53:58,880 --> 00:54:00,570 you can build models. 988 00:54:00,570 --> 00:54:02,030 And that's what we do. 989 00:54:02,030 --> 00:54:05,990 You're going to see a lot of that in this course. 990 00:54:05,990 --> 00:54:11,070 OK, the other thing that medicine tries to do 991 00:54:11,070 --> 00:54:14,430 is not to cure people but to keep them healthy. 992 00:54:14,430 --> 00:54:19,200 And this has been pretty much the domain of the public health 993 00:54:19,200 --> 00:54:20,730 infrastructure. 994 00:54:20,730 --> 00:54:24,980 So if you go across the river to the Harvard Medical area, 995 00:54:24,980 --> 00:54:26,730 there are a couple of big buildings, which 996 00:54:26,730 --> 00:54:28,560 is the Harvard School of Public Health, 997 00:54:28,560 --> 00:54:31,720 and this is what they're all about. 998 00:54:31,720 --> 00:54:35,490 So they do things like tracking disease prevalence 999 00:54:35,490 --> 00:54:37,860 and tracking infections, and worrying 1000 00:54:37,860 --> 00:54:40,110 about quarantining people. 1001 00:54:40,110 --> 00:54:42,330 They also do a lot of the kind of work 1002 00:54:42,330 --> 00:54:45,570 we're going to talk about in this class, which is modeling 1003 00:54:45,570 --> 00:54:50,130 in order to try to understand what's going on in individual's 1004 00:54:50,130 --> 00:54:52,620 health, in the health of a population, 1005 00:54:52,620 --> 00:54:55,620 in the operations of a health care system. 1006 00:54:55,620 --> 00:54:57,810 So they're very much into this. 1007 00:54:57,810 --> 00:55:03,320 Now historically, I looked back and it turns out 1008 00:55:03,320 --> 00:55:07,160 there's something called the London Bills of Mortality 1009 00:55:07,160 --> 00:55:12,890 in the 17th century, started by a gentleman named John Graunt. 1010 00:55:12,890 --> 00:55:17,210 And he was interested just in figuring out, 1011 00:55:17,210 --> 00:55:20,090 how long do people live? 1012 00:55:20,090 --> 00:55:24,020 And so he came up with these bills of mortality, 1013 00:55:24,020 --> 00:55:26,930 where he went around to different parts of London, 1014 00:55:26,930 --> 00:55:29,780 talked to undertakers and hospitals 1015 00:55:29,780 --> 00:55:34,130 and whatever health care providers existed at the time, 1016 00:55:34,130 --> 00:55:38,210 and collected data on what people died 1017 00:55:38,210 --> 00:55:40,890 and how many people were living in that area. 1018 00:55:40,890 --> 00:55:46,550 And so for example, he estimated that the mortality before age 1019 00:55:46,550 --> 00:55:52,220 six in the 17th century-- this was a long time ago, 1600s-- 1020 00:55:52,220 --> 00:55:54,750 was about 36%. 1021 00:55:54,750 --> 00:56:00,060 So if you were a kid, your chances of making it to age six 1022 00:56:00,060 --> 00:56:06,720 were only about 64%, so less than 2/3. 1023 00:56:06,720 --> 00:56:08,850 Kind of shocking. 1024 00:56:08,850 --> 00:56:12,030 In the 18th century, people you've never heard 1025 00:56:12,030 --> 00:56:14,850 of-- and Linnaeus, who you probably have heard 1026 00:56:14,850 --> 00:56:17,790 of, because he was one of the early taxonomists 1027 00:56:17,790 --> 00:56:22,710 for biological and animal species and so on-- 1028 00:56:22,710 --> 00:56:26,580 made the first attempts at systemic classification. 1029 00:56:26,580 --> 00:56:31,110 In the mid-1850s, mid-1800s, there 1030 00:56:31,110 --> 00:56:34,890 was a Congress of the First International Statistical 1031 00:56:34,890 --> 00:56:36,270 Congress. 1032 00:56:36,270 --> 00:56:39,990 And a gentleman named William Farr came up 1033 00:56:39,990 --> 00:56:44,110 with an interesting categorization that said, well, 1034 00:56:44,110 --> 00:56:46,980 if we're going to taxonomize the diseases, 1035 00:56:46,980 --> 00:56:50,010 we should separate epidemic diseases 1036 00:56:50,010 --> 00:56:54,480 from constitutional diseases from local diseases, 1037 00:56:54,480 --> 00:56:57,060 whereby "local" he means affecting 1038 00:56:57,060 --> 00:57:02,810 a particular part of the body from developmental diseases. 1039 00:57:02,810 --> 00:57:06,070 So this is things like stunted growth 1040 00:57:06,070 --> 00:57:10,930 or failure of mental development or speech development, 1041 00:57:10,930 --> 00:57:14,000 and then diseases that are the direct result of violence. 1042 00:57:14,000 --> 00:57:18,880 So this is things like broken bones and bar fight results 1043 00:57:18,880 --> 00:57:21,110 and stuff like that. 1044 00:57:21,110 --> 00:57:24,400 So that was the first classification 1045 00:57:24,400 --> 00:57:28,780 of disease in about 1853. 1046 00:57:28,780 --> 00:57:32,170 Note, by the way, that this is before Louis Pasteur 1047 00:57:32,170 --> 00:57:36,260 and his theory of the germ cause of disease. 1048 00:57:36,260 --> 00:57:38,500 And so this was a pretty early attempt, 1049 00:57:38,500 --> 00:57:42,400 and obviously could have benefited from what 1050 00:57:42,400 --> 00:57:45,010 Pasteur later discovered. 1051 00:57:45,010 --> 00:57:49,210 So by the 1890s, which is post-Pasteur, 1052 00:57:49,210 --> 00:57:51,730 they came up with a classification 1053 00:57:51,730 --> 00:57:54,730 that was a hierarchic classification, 44 1054 00:57:54,730 --> 00:58:00,910 top-level hierarchies broken up into 99 lower-level categories 1055 00:58:00,910 --> 00:58:04,390 and 161 particular titles. 1056 00:58:04,390 --> 00:58:07,990 And they adopted this as a way of getting, 1057 00:58:07,990 --> 00:58:10,900 typically, mortality data of what was it 1058 00:58:10,900 --> 00:58:12,820 that people were dying of. 1059 00:58:12,820 --> 00:58:17,740 And by the 1920s, you've heard of ICD-- 1060 00:58:17,740 --> 00:58:20,090 ICD-9, ICD-10. 1061 00:58:20,090 --> 00:58:23,980 So this is currently used as a way of classifying diseases 1062 00:58:23,980 --> 00:58:26,530 and disorders. 1063 00:58:26,530 --> 00:58:30,370 The International List of the Causes of Death 1064 00:58:30,370 --> 00:58:35,410 was the first ICD back in, I think, the 1920s. 1065 00:58:35,410 --> 00:58:39,820 And then it kept developing through multiple versions. 1066 00:58:39,820 --> 00:58:43,210 In 1975, ICD-9 was adopted. 1067 00:58:43,210 --> 00:58:46,660 In 2015, ICD-10. 1068 00:58:46,660 --> 00:58:48,880 And these are under the control of the World Health 1069 00:58:48,880 --> 00:58:52,720 Organization, which is now a UN agency, although I think 1070 00:58:52,720 --> 00:58:56,290 it predates the UN actually. 1071 00:58:56,290 --> 00:59:00,630 And then we have ICD-9 CM and ICD-10 CM, 1072 00:59:00,630 --> 00:59:04,150 are US Clinical Modifications that 1073 00:59:04,150 --> 00:59:08,390 are an extension of the ICD-9 and 10 coding. 1074 00:59:08,390 --> 00:59:12,130 And they are primarily used for billing. 1075 00:59:12,130 --> 00:59:15,490 But they're also used for epidemiological research. 1076 00:59:15,490 --> 00:59:21,040 And if you look at the Centers for Disease Control, CDC, 1077 00:59:21,040 --> 00:59:24,280 they collect death certificates like this 1078 00:59:24,280 --> 00:59:26,180 from all over the country. 1079 00:59:26,180 --> 00:59:30,970 And so this is a person who died of a cerebral hemorrhage which 1080 00:59:30,970 --> 00:59:35,140 was due to nephritis, which was due to cirrhosis of the liver. 1081 00:59:35,140 --> 00:59:38,170 And so you can use this kind of data to say, 1082 00:59:38,170 --> 00:59:40,820 well, here's the immediate cause of death, 1083 00:59:40,820 --> 00:59:43,240 here's sort of the proximate cause of death, 1084 00:59:43,240 --> 00:59:47,010 and here's the underlying cause of death. 1085 00:59:47,010 --> 00:59:50,310 And so this is the sort of statistical data 1086 00:59:50,310 --> 00:59:52,800 that we now have available. 1087 00:59:52,800 --> 00:59:59,352 Now, do any of you watch the PBS show Victoria? 1088 00:59:59,352 --> 01:00:01,070 Nobody? 1089 01:00:01,070 --> 01:00:02,720 You're not television watchers. 1090 01:00:02,720 --> 01:00:06,260 All right, that's pretty cool. 1091 01:00:06,260 --> 01:00:12,410 I was stunned, because as I was preparing this lecture 1092 01:00:12,410 --> 01:00:15,500 and I had the next slide, it turns out 1093 01:00:15,500 --> 01:00:17,840 this plays a role in one of the episodes 1094 01:00:17,840 --> 01:00:20,150 that was broadcast about a week and a half ago. 1095 01:00:23,210 --> 01:00:30,050 So in the 1850s, there was a big outbreak of cholera in London. 1096 01:00:30,050 --> 01:00:34,460 And John Snow was a doctor who did 1097 01:00:34,460 --> 01:00:38,780 this amazing epidemiological study to try to figure out 1098 01:00:38,780 --> 01:00:40,820 what was causing cholera. 1099 01:00:40,820 --> 01:00:44,600 The accepted opinion was that cholera was caused by miasma. 1100 01:00:47,420 --> 01:00:49,652 What's a miasma? 1101 01:00:49,652 --> 01:00:51,110 STUDENT: Bad air. 1102 01:00:51,110 --> 01:00:53,360 PETER SZOLOVITS: Bad air, OK? 1103 01:00:53,360 --> 01:00:54,620 So it's bad air. 1104 01:00:54,620 --> 01:01:00,710 Somehow, bad air was causing people to get sick and die. 1105 01:01:00,710 --> 01:01:04,040 And several hundred people died. 1106 01:01:04,040 --> 01:01:09,140 Whereas Snow started plotting on a map of the area in London 1107 01:01:09,140 --> 01:01:13,660 where these were concentrated where everybody lived. 1108 01:01:13,660 --> 01:01:16,690 And what he discovered, interestingly enough, 1109 01:01:16,690 --> 01:01:19,660 is that right in the middle of Broad Street, 1110 01:01:19,660 --> 01:01:23,560 which is pretty much at the epicenter of all these people 1111 01:01:23,560 --> 01:01:28,530 dying, was a water pump that everybody in the neighborhood 1112 01:01:28,530 --> 01:01:29,040 used. 1113 01:01:29,040 --> 01:01:35,170 And that water pump, its supply had become infected by cholera. 1114 01:01:35,170 --> 01:01:37,140 And so people were pumping water, 1115 01:01:37,140 --> 01:01:40,230 taking it home, drinking it, and then dying, 1116 01:01:40,230 --> 01:01:42,630 or at least getting very sick. 1117 01:01:42,630 --> 01:01:45,900 And he looked at this and he said, well, 1118 01:01:45,900 --> 01:01:52,620 if we turn off that pump, the epidemic will stop. 1119 01:01:52,620 --> 01:01:55,890 And he actually went to the queen, Queen Victoria-- 1120 01:01:55,890 --> 01:01:59,250 hence the tie-in to the television show-- 1121 01:01:59,250 --> 01:02:03,540 and convinced her that this was worth trying, because they 1122 01:02:03,540 --> 01:02:05,670 didn't have any better ideas. 1123 01:02:05,670 --> 01:02:08,010 And they took the pump handle off the pump, 1124 01:02:08,010 --> 01:02:12,030 and sure enough the cholera epidemic abated. 1125 01:02:12,030 --> 01:02:17,320 Now, of course the underlying problem was sanitation. 1126 01:02:17,320 --> 01:02:18,610 And they didn't fix that. 1127 01:02:18,610 --> 01:02:21,520 That took longer. 1128 01:02:21,520 --> 01:02:24,070 But what's interesting is here is 1129 01:02:24,070 --> 01:02:30,590 a 2003 study of the spread of West Nile virus. 1130 01:02:30,590 --> 01:02:35,710 So this is mosquitoes that are biting people and infecting 1131 01:02:35,710 --> 01:02:38,650 them with this nasty disease. 1132 01:02:38,650 --> 01:02:41,920 And they actually used very similar techniques 1133 01:02:41,920 --> 01:02:45,070 to figure out that maybe this was coming in 1134 01:02:45,070 --> 01:02:48,310 on airplanes through JFK. 1135 01:02:48,310 --> 01:02:53,470 So mosquitoes were hitching a ride on an airplane 1136 01:02:53,470 --> 01:02:55,780 and coming into the US. 1137 01:02:55,780 --> 01:03:01,675 We need to build a border wall against mosquitoes. 1138 01:03:04,470 --> 01:03:08,120 There is also a very controversial practice 1139 01:03:08,120 --> 01:03:11,870 that used to be used a lot by public health officials, which 1140 01:03:11,870 --> 01:03:14,400 was to quarantine people. 1141 01:03:14,400 --> 01:03:18,110 And so there are lots of examples. 1142 01:03:18,110 --> 01:03:22,200 Anybody's relatives come through Ellis Island? 1143 01:03:22,200 --> 01:03:23,610 Must be a few. 1144 01:03:23,610 --> 01:03:27,240 OK, so they were subject to quarantine. 1145 01:03:27,240 --> 01:03:30,480 If you were sick when you arrived at Ellis Island 1146 01:03:30,480 --> 01:03:33,630 and they didn't know exactly how sick you were, 1147 01:03:33,630 --> 01:03:36,840 they would put you in a building and wait a month 1148 01:03:36,840 --> 01:03:39,540 and see if you got better or if you got worse, 1149 01:03:39,540 --> 01:03:42,870 and then decide whether to send you back or to let you in. 1150 01:03:42,870 --> 01:03:45,060 So that was a pretty common practice. 1151 01:03:45,060 --> 01:03:47,940 There's a famous story of Typhoid Mary, 1152 01:03:47,940 --> 01:03:50,610 who was a carrier of typhoid fever 1153 01:03:50,610 --> 01:03:53,280 but was not herself affected. 1154 01:03:53,280 --> 01:03:55,460 Unfortunately, she was a cook. 1155 01:03:55,460 --> 01:04:00,210 And wherever she was employed, people got really sick. 1156 01:04:00,210 --> 01:04:03,690 And eventually, the New York Department of Health 1157 01:04:03,690 --> 01:04:09,810 forcibly essentially jailed her in some sanatorium 1158 01:04:09,810 --> 01:04:11,910 in order to keep her from continuing 1159 01:04:11,910 --> 01:04:15,120 to infect people-- it was a very controversial case, as you 1160 01:04:15,120 --> 01:04:17,160 might imagine. 1161 01:04:17,160 --> 01:04:18,870 You don't have to go that far back. 1162 01:04:18,870 --> 01:04:25,170 Here's a 1987 article from UPI from The Chicago Tribune. 1163 01:04:25,170 --> 01:04:28,200 So Jesse Helms, who was a senator, 1164 01:04:28,200 --> 01:04:33,550 was calling for everybody who has AIDS to be quarantined. 1165 01:04:33,550 --> 01:04:36,220 So fortunately, that didn't happen. 1166 01:04:36,220 --> 01:04:40,780 But the idea is still around, to say, well, 1167 01:04:40,780 --> 01:04:43,990 we're going to stop this infection by quarantining 1168 01:04:43,990 --> 01:04:45,280 people. 1169 01:04:45,280 --> 01:04:51,740 And then here's a recent report about the Ebola response 1170 01:04:51,740 --> 01:04:55,090 in Africa over the past few years, 1171 01:04:55,090 --> 01:04:59,230 when Ebola was ravaging parts of that continent. 1172 01:04:59,230 --> 01:05:03,160 And their conclusions are it's controversial, 1173 01:05:03,160 --> 01:05:07,210 a debated issue, significant risks related to human rights. 1174 01:05:07,210 --> 01:05:09,970 Quarantine should be used as a last resort. 1175 01:05:09,970 --> 01:05:13,570 Quarantines in urban areas are really hard. 1176 01:05:13,570 --> 01:05:15,900 Mobile populations make it hard. 1177 01:05:15,900 --> 01:05:20,920 And this is the most technical conclusion, 1178 01:05:20,920 --> 01:05:23,320 that if you're going to quarantine a bunch of people, 1179 01:05:23,320 --> 01:05:26,720 you have a huge waste disposal problem on your hands. 1180 01:05:26,720 --> 01:05:29,680 Because if you have people who might have Ebola, 1181 01:05:29,680 --> 01:05:31,900 you can't just take their garbage 1182 01:05:31,900 --> 01:05:33,730 and throw it out somewhere. 1183 01:05:33,730 --> 01:05:36,700 You have to dispose of it properly. 1184 01:05:36,700 --> 01:05:39,910 OK, so the last thing I wanted to talk about-- 1185 01:05:39,910 --> 01:05:45,260 hopefully mercifully short-- will be paying for health care. 1186 01:05:45,260 --> 01:05:49,780 So I remember reading about 20 years ago 1187 01:05:49,780 --> 01:05:53,260 that if you bought a Chevy from General Motors, 1188 01:05:53,260 --> 01:05:56,740 they spent more money on health insurance and health 1189 01:05:56,740 --> 01:06:00,580 care for their employees than they did on the steel that 1190 01:06:00,580 --> 01:06:02,498 went into your car. 1191 01:06:02,498 --> 01:06:03,415 That's pretty amazing. 1192 01:06:06,600 --> 01:06:07,570 So why is this? 1193 01:06:07,570 --> 01:06:10,440 Well, essentially, there's an insatiable demand 1194 01:06:10,440 --> 01:06:12,780 for health care, right? 1195 01:06:12,780 --> 01:06:17,970 Nobody wants to die, except for the suicidal people. 1196 01:06:17,970 --> 01:06:22,890 And so if I'm sick, I want the best care possible, 1197 01:06:22,890 --> 01:06:26,340 and I want as much of it as possible. 1198 01:06:26,340 --> 01:06:29,940 Because you know, what is more important in life 1199 01:06:29,940 --> 01:06:33,040 than continuing to live? 1200 01:06:33,040 --> 01:06:39,330 So we also have gotten better at making drugs and better tests, 1201 01:06:39,330 --> 01:06:40,410 and so on. 1202 01:06:40,410 --> 01:06:43,410 I remember one MRI machines became 1203 01:06:43,410 --> 01:06:47,040 popular about 30 years ago. 1204 01:06:47,040 --> 01:06:49,120 The state of Massachusetts, for example, 1205 01:06:49,120 --> 01:06:51,750 had a commission that you had to convince 1206 01:06:51,750 --> 01:06:57,360 them to be allowed to buy an MRI machine for your hospital, 1207 01:06:57,360 --> 01:07:00,570 because MRI machines were very expensive 1208 01:07:00,570 --> 01:07:04,260 and MRIs were, at that time, hugely expensive. 1209 01:07:04,260 --> 01:07:07,380 And so they wanted to contain the cost of health care 1210 01:07:07,380 --> 01:07:10,020 by limiting the number of such machines. 1211 01:07:10,020 --> 01:07:12,070 Well, eventually the costs came down. 1212 01:07:12,070 --> 01:07:13,600 And so we're doing better. 1213 01:07:13,600 --> 01:07:15,090 But if you read the newspapers, you 1214 01:07:15,090 --> 01:07:18,550 see that drug therapy is very expensive. 1215 01:07:18,550 --> 01:07:24,060 We have these wonder drugs for rare diseases or cancers 1216 01:07:24,060 --> 01:07:29,490 that cost $1 million a year to pay for your dosage. 1217 01:07:29,490 --> 01:07:33,090 And so there is a high human motivation 1218 01:07:33,090 --> 01:07:36,450 to do this, and not much pushback-- 1219 01:07:36,450 --> 01:07:38,970 except from insurance companies. 1220 01:07:38,970 --> 01:07:43,410 But they just pass the cost on in insurance contracts. 1221 01:07:43,410 --> 01:07:45,630 There's also waste. 1222 01:07:45,630 --> 01:07:48,690 So there are lots of stories about half 1223 01:07:48,690 --> 01:07:51,120 of health care expenses are spent 1224 01:07:51,120 --> 01:07:54,090 in the last year of somebody's life. 1225 01:07:54,090 --> 01:07:57,390 Although, Ingelfinger, who was the editor of The New England 1226 01:07:57,390 --> 01:08:00,820 Journal, gave a talk here about 25 years ago. 1227 01:08:00,820 --> 01:08:03,420 And he said, you know, when I was a practicing doctor, 1228 01:08:03,420 --> 01:08:06,210 no patient ever came into my office saying, doc, 1229 01:08:06,210 --> 01:08:09,120 I'm in the last year of my life. 1230 01:08:09,120 --> 01:08:12,900 And so that was a difficult criterion 1231 01:08:12,900 --> 01:08:15,660 to try to operationalize. 1232 01:08:15,660 --> 01:08:18,359 There are marginally useful procedures. 1233 01:08:18,359 --> 01:08:20,609 The IOM estimated that there are sort 1234 01:08:20,609 --> 01:08:24,750 of 40,000 to 100,000 quote unquote unnecessary deaths 1235 01:08:24,750 --> 01:08:26,649 per year-- 1236 01:08:26,649 --> 01:08:28,410 in other words, deaths that could 1237 01:08:28,410 --> 01:08:31,140 be avoided by just being more careful and a little bit 1238 01:08:31,140 --> 01:08:32,490 smarter. 1239 01:08:32,490 --> 01:08:36,899 Well, so the result of this is that if you look at health care 1240 01:08:36,899 --> 01:08:41,250 spending as a percentage of gross domestic product 1241 01:08:41,250 --> 01:08:47,069 from 1970 to I think 2017, I believe, on this graph, 1242 01:08:47,069 --> 01:08:50,279 what you see is one real outlier. 1243 01:08:50,279 --> 01:08:54,500 And that's the United States on top. 1244 01:08:54,500 --> 01:08:58,939 So I've selected a few of these just to look at. 1245 01:08:58,939 --> 01:09:01,000 There's the US on top. 1246 01:09:01,000 --> 01:09:05,109 France, Germany, a lot of the European countries 1247 01:09:05,109 --> 01:09:11,109 are roughly at that highest of the crowd level. 1248 01:09:11,109 --> 01:09:12,460 Canada is down there. 1249 01:09:12,460 --> 01:09:14,020 The UK is a little lower. 1250 01:09:14,020 --> 01:09:15,760 Spain is a little lower. 1251 01:09:15,760 --> 01:09:17,140 Israel is a little lower. 1252 01:09:17,140 --> 01:09:20,620 Turkey is the lowest of the OECD countries 1253 01:09:20,620 --> 01:09:25,000 in terms of percentage of GDP that they spend on health care. 1254 01:09:25,000 --> 01:09:26,590 So well, that's OK. 1255 01:09:26,590 --> 01:09:30,130 But maybe we're getting more for our money 1256 01:09:30,130 --> 01:09:32,359 than these other countries. 1257 01:09:32,359 --> 01:09:34,600 And so there are a lot of analyses 1258 01:09:34,600 --> 01:09:36,160 that look at stuff like this. 1259 01:09:36,160 --> 01:09:39,310 They say, well, if we spend so much 1260 01:09:39,310 --> 01:09:43,990 money per patient per year, what do 1261 01:09:43,990 --> 01:09:46,090 we get in terms of the simplest thing 1262 01:09:46,090 --> 01:09:48,729 to measure, which is life expectancy? 1263 01:09:48,729 --> 01:09:50,859 How long do people live? 1264 01:09:50,859 --> 01:09:53,950 And what we discover is that in the United States, 1265 01:09:53,950 --> 01:09:59,440 we're spending $9,000 a year on patients 1266 01:09:59,440 --> 01:10:05,170 and we're getting a life span of somewhere in the high 70s. 1267 01:10:05,170 --> 01:10:08,290 So this is 2015 data. 1268 01:10:08,290 --> 01:10:11,800 Whereas in Switzerland, they're spending about $6,000-- 1269 01:10:11,800 --> 01:10:17,800 so about 2/3-- and they're getting 83 years or something 1270 01:10:17,800 --> 01:10:22,150 of life for the same price, and so 1271 01:10:22,150 --> 01:10:24,610 on for all these different countries. 1272 01:10:24,610 --> 01:10:27,880 By the way, this is all from Gapminder, 1273 01:10:27,880 --> 01:10:31,023 which is a wonderful data visualization tool. 1274 01:10:31,023 --> 01:10:32,440 And I don't have time to show you, 1275 01:10:32,440 --> 01:10:34,990 but you can click on individual lines 1276 01:10:34,990 --> 01:10:40,280 there and slide the slider about what euro you're talking about, 1277 01:10:40,280 --> 01:10:41,800 and the data moves. 1278 01:10:41,800 --> 01:10:44,290 And it's beautiful, and it's a wonderful way 1279 01:10:44,290 --> 01:10:46,640 of understanding it. 1280 01:10:46,640 --> 01:10:52,230 So there's an important thing to remember, 1281 01:10:52,230 --> 01:10:54,750 which was taught to me by my friend Chris 1282 01:10:54,750 --> 01:10:57,420 Dede at the Harvard Education School. 1283 01:10:57,420 --> 01:11:00,480 And that is that it's not even good enough to stand still. 1284 01:11:00,480 --> 01:11:04,620 So he suggested the following scenario. 1285 01:11:04,620 --> 01:11:07,350 If you look at the growth of productivity 1286 01:11:07,350 --> 01:11:12,240 over this period of 10 years by industry, 1287 01:11:12,240 --> 01:11:14,520 you discover that productivity went up 1288 01:11:14,520 --> 01:11:18,990 by seven point something percent for durable goods 1289 01:11:18,990 --> 01:11:23,420 and went down by something like 2% for mining. 1290 01:11:23,420 --> 01:11:26,240 About 1% for construction. 1291 01:11:26,240 --> 01:11:31,440 Information technologies grew by 5 and 1/2% or something. 1292 01:11:31,440 --> 01:11:34,430 So if you ask the question, what happens 1293 01:11:34,430 --> 01:11:37,280 if the demand for these goods remains 1294 01:11:37,280 --> 01:11:41,030 constant over a period of time? 1295 01:11:41,030 --> 01:11:45,710 And what you discover is that because the more productive 1296 01:11:45,710 --> 01:11:48,590 things become cheaper, they wind up 1297 01:11:48,590 --> 01:11:52,610 occupying a smaller fraction of the total amount of money 1298 01:11:52,610 --> 01:11:55,370 that's being spent. 1299 01:11:55,370 --> 01:11:59,500 So your computer, your laptop, is a lot cheaper today 1300 01:11:59,500 --> 01:12:02,210 than it was 30 years ago. 1301 01:12:02,210 --> 01:12:04,300 And so that means that the amount 1302 01:12:04,300 --> 01:12:08,350 of spending that people do on things like information 1303 01:12:08,350 --> 01:12:13,180 technology, at least per item, is much lower 1304 01:12:13,180 --> 01:12:14,890 than it used to be. 1305 01:12:14,890 --> 01:12:18,160 And if in the aggregate it's also lower than it used to be, 1306 01:12:18,160 --> 01:12:22,020 that means that something else must be higher, right? 1307 01:12:22,020 --> 01:12:24,640 Because it sums to 100%. 1308 01:12:24,640 --> 01:12:27,780 And so what this shows is that if you 1309 01:12:27,780 --> 01:12:31,830 spend 30 years at the same rates of productivity growth, 1310 01:12:31,830 --> 01:12:37,080 mining grows from whatever fraction of the economy 1311 01:12:37,080 --> 01:12:42,650 it was to something that's about three times as big a fraction. 1312 01:12:42,650 --> 01:12:44,450 Right? 1313 01:12:44,450 --> 01:12:48,290 And if productivity growth is better, 1314 01:12:48,290 --> 01:12:52,770 then that sector of the economy shrinks. 1315 01:12:52,770 --> 01:12:55,680 So I think something like this is 1316 01:12:55,680 --> 01:12:57,930 happening in health care, which is 1317 01:12:57,930 --> 01:13:00,240 that there's infinite demand. 1318 01:13:00,240 --> 01:13:02,940 And health care is not terribly productive. 1319 01:13:02,940 --> 01:13:06,210 We're not getting better as fast as electronics 1320 01:13:06,210 --> 01:13:09,890 is getting better, for example. 1321 01:13:09,890 --> 01:13:13,250 So people have tried doing various things. 1322 01:13:13,250 --> 01:13:18,038 "Managed care" was the buzzword of the 1980s and '90s. 1323 01:13:18,038 --> 01:13:19,580 And they said, well, what we're going 1324 01:13:19,580 --> 01:13:22,490 to do is to prevent people from overusing 1325 01:13:22,490 --> 01:13:27,410 medical services by requiring pre-admission review, continued 1326 01:13:27,410 --> 01:13:31,160 stay review, second surgical opinion. 1327 01:13:31,160 --> 01:13:34,250 We're going to have post-care management, where 1328 01:13:34,250 --> 01:13:36,140 if you're released from the hospital 1329 01:13:36,140 --> 01:13:38,840 and you're in that second of the cycles, 1330 01:13:38,840 --> 01:13:41,960 people will call you at home and try to help you out and make 1331 01:13:41,960 --> 01:13:45,200 sure that you're doing whatever is best to keep you out 1332 01:13:45,200 --> 01:13:46,770 of the hospital. 1333 01:13:46,770 --> 01:13:47,270 And 1334 01:13:47,270 --> 01:13:49,880 We're going to try various experiments, 1335 01:13:49,880 --> 01:13:53,150 like institutional arrangements, that say, well, 1336 01:13:53,150 --> 01:14:00,620 if I as a doctor agree to refer all my patients to Mass General 1337 01:14:00,620 --> 01:14:05,360 rather than to the Brigham or the BI, they'll pay me extra. 1338 01:14:05,360 --> 01:14:10,380 And they'll get some kind of efficiencies from aggregation. 1339 01:14:10,380 --> 01:14:14,030 And so maybe that's one way of controlling costs. 1340 01:14:14,030 --> 01:14:17,990 So leakage is the idea of keeping people in-system. 1341 01:14:17,990 --> 01:14:20,270 And capitation is an interesting idea, 1342 01:14:20,270 --> 01:14:23,000 which says that instead of paying 1343 01:14:23,000 --> 01:14:25,760 for what the hospital does for me 1344 01:14:25,760 --> 01:14:28,400 or what the doctor does for me, we simply 1345 01:14:28,400 --> 01:14:34,290 pay him a flat fee for the year to take care of me. 1346 01:14:34,290 --> 01:14:36,480 And that takes away the incentive for him 1347 01:14:36,480 --> 01:14:39,572 to do more and more and more to get paid more. 1348 01:14:39,572 --> 01:14:41,280 But of course, it gives them an incentive 1349 01:14:41,280 --> 01:14:44,940 to do less and less and less so that he doesn't 1350 01:14:44,940 --> 01:14:46,380 have to spend as much money. 1351 01:14:46,380 --> 01:14:48,450 And so it's sort of a knife balance 1352 01:14:48,450 --> 01:14:50,250 to figure out how to do this. 1353 01:14:50,250 --> 01:14:53,170 But that's an important component. 1354 01:14:53,170 --> 01:14:56,130 So if you look at the evaluation of managed care 1355 01:14:56,130 --> 01:14:59,370 a long time ago, what they said was it 1356 01:14:59,370 --> 01:15:05,100 helped reduce inpatient costs by increasing outpatient costs. 1357 01:15:05,100 --> 01:15:07,200 So what it's done is it's pushed people 1358 01:15:07,200 --> 01:15:11,220 from going to the hospital into going to their doctor's office. 1359 01:15:11,220 --> 01:15:14,370 But it's been pretty much a wash in terms of overall spending. 1360 01:15:17,680 --> 01:15:20,320 Doctors also hated managed care. 1361 01:15:20,320 --> 01:15:22,900 I was sitting with one of my colleagues 1362 01:15:22,900 --> 01:15:26,830 at a Boston hospital, and an insurance company clerk 1363 01:15:26,830 --> 01:15:32,500 called him to dun him for having ordered a certain test 1364 01:15:32,500 --> 01:15:34,030 on a heart patient. 1365 01:15:34,030 --> 01:15:36,550 And so he was furious. 1366 01:15:36,550 --> 01:15:39,640 And he turns to her and says, so which medical school 1367 01:15:39,640 --> 01:15:41,740 do you have your diploma from? 1368 01:15:41,740 --> 01:15:44,340 And of course, she doesn't have a medical degree. 1369 01:15:44,340 --> 01:15:47,050 She's following some rules on a sheet 1370 01:15:47,050 --> 01:15:51,730 about how to harass doctors not to order expensive tests. 1371 01:15:51,730 --> 01:15:55,900 And so we have Edward Annis, the past president of the AMA, 1372 01:15:55,900 --> 01:15:58,510 who says, well, in the glory days 1373 01:15:58,510 --> 01:16:01,780 there was no bureaucratic regimentation, no forms, 1374 01:16:01,780 --> 01:16:03,370 no blah, blah, blah. 1375 01:16:03,370 --> 01:16:05,980 And all my patients were happy, and I was happy, 1376 01:16:05,980 --> 01:16:08,380 and things were ideal. 1377 01:16:08,380 --> 01:16:10,900 If you actually look back at those days, 1378 01:16:10,900 --> 01:16:15,170 it wasn't as good as the cracks it up to be. 1379 01:16:15,170 --> 01:16:17,230 And some of those issues of disparity 1380 01:16:17,230 --> 01:16:19,720 that we were talking about were horrible. 1381 01:16:19,720 --> 01:16:22,180 So for his patients who were rich 1382 01:16:22,180 --> 01:16:26,500 and who could afford to see him, life was pretty good. 1383 01:16:26,500 --> 01:16:31,840 But not so much for underserved populations. 1384 01:16:31,840 --> 01:16:37,750 So you've seen ObamaCare come and partly go, and continues 1385 01:16:37,750 --> 01:16:39,670 to be controversial. 1386 01:16:39,670 --> 01:16:46,450 But it's trying to foster better information technology 1387 01:16:46,450 --> 01:16:51,080 as a basis for getting doctors to make better decisions. 1388 01:16:51,080 --> 01:16:54,560 It's trying to foster these accountable care organizations, 1389 01:16:54,560 --> 01:16:56,800 which is a version of capitation, 1390 01:16:56,800 --> 01:17:00,790 to put the pressure on to reduce the amount of health services 1391 01:17:00,790 --> 01:17:03,400 that people are asking for. 1392 01:17:03,400 --> 01:17:07,960 There is a hospital readmission reduction program now 1393 01:17:07,960 --> 01:17:14,050 that says if you are a Medicare patient, for example, 1394 01:17:14,050 --> 01:17:16,210 and you're discharged from the hospital 1395 01:17:16,210 --> 01:17:21,090 and you're readmitted within 30 days of your discharge, 1396 01:17:21,090 --> 01:17:24,120 then they're going to dun you and not pay you 1397 01:17:24,120 --> 01:17:25,920 for that readmission, or not pay you 1398 01:17:25,920 --> 01:17:27,870 for part of that readmission. 1399 01:17:27,870 --> 01:17:31,530 But if you look at the statistics, which I just did, 1400 01:17:31,530 --> 01:17:35,400 that's the distribution of the payment adjustment factors. 1401 01:17:35,400 --> 01:17:39,066 So it turns out the lowest number is 97%. 1402 01:17:39,066 --> 01:17:41,760 So a 3% decrease in reimbursement 1403 01:17:41,760 --> 01:17:44,610 is something that the CFO of your hospital 1404 01:17:44,610 --> 01:17:45,940 would really care about. 1405 01:17:45,940 --> 01:17:50,310 But it's not like a 25% reduction in reimbursements. 1406 01:17:50,310 --> 01:17:53,235 So this has had a fairly minor effect. 1407 01:17:56,780 --> 01:18:01,790 Let me just finish by saying that money determines much. 1408 01:18:01,790 --> 01:18:05,210 From our point of view, one of the problems we face 1409 01:18:05,210 --> 01:18:09,410 is that IT traditionally gets about 1% to 2% 1410 01:18:09,410 --> 01:18:14,720 of spending in medical centers, whereas it gets about 6% or 7% 1411 01:18:14,720 --> 01:18:19,850 in business overall and about 10% to 12% for banking. 1412 01:18:19,850 --> 01:18:24,230 And a lot of these systems are managed by accountants, 1413 01:18:24,230 --> 01:18:26,390 although that is slowly changing. 1414 01:18:26,390 --> 01:18:31,010 So in the 1990s, HST with Harvard 1415 01:18:31,010 --> 01:18:35,360 started a training program for medical doctors 1416 01:18:35,360 --> 01:18:39,260 to become medical informaticians-- so practicing 1417 01:18:39,260 --> 01:18:40,970 this sort of witchcraft. 1418 01:18:40,970 --> 01:18:43,820 And our first two graduates, one of them 1419 01:18:43,820 --> 01:18:47,300 is now CIO at the Beth Israel Deaconess. 1420 01:18:47,300 --> 01:18:50,330 The second one is CIO at Children's Hospital. 1421 01:18:50,330 --> 01:18:53,540 And so one of my big successes personally 1422 01:18:53,540 --> 01:18:56,210 has been to displace some accountants 1423 01:18:56,210 --> 01:18:58,610 by doctors who actually understand 1424 01:18:58,610 --> 01:19:01,580 this technology to some extent. 1425 01:19:01,580 --> 01:19:05,130 OK, I think that's all I'm going to say. 1426 01:19:05,130 --> 01:19:08,780 There's a funny last slide here, which 1427 01:19:08,780 --> 01:19:12,290 has a pointer that I would want you to remember. 1428 01:19:12,290 --> 01:19:15,530 The slides will be up on our website. 1429 01:19:15,530 --> 01:19:17,330 You can follow it. 1430 01:19:17,330 --> 01:19:19,460 MIT has a program called GEMS. 1431 01:19:19,460 --> 01:19:23,840 It's the General Education in Medical Sciences, intended 1432 01:19:23,840 --> 01:19:27,170 as a minor program for people in the PhD program 1433 01:19:27,170 --> 01:19:29,090 in some other field. 1434 01:19:29,090 --> 01:19:33,650 And if you're serious about really concentrating on health 1435 01:19:33,650 --> 01:19:37,640 care, developing at least the kind of understanding 1436 01:19:37,640 --> 01:19:41,250 of the health care process that I've tried to give you today 1437 01:19:41,250 --> 01:19:44,690 and that would allow you to play a doctor on television 1438 01:19:44,690 --> 01:19:46,340 is really important. 1439 01:19:46,340 --> 01:19:49,550 And there is a program that helps you achieve that, 1440 01:19:49,550 --> 01:19:51,170 which I commend to people. 1441 01:19:51,170 --> 01:19:54,130 OK, see you next week.