post by Bill Gardner
Harold Pollack commented on a classic paper by Kevin Murphy and Robert Topol that changed how I see the world (see also Austin Frakt). I want to comment on what I have found in the paper, and a moral problem it poses.
Murphy and Topol ask, are we getting anything from the GDP (now 17%) we consume in health care, and from the billions we invest each year in medical research ($31.2B for the NIH alone)?
The answer is YES:
We calculate (i) the social value of increased longevity that took place from 1970 to 1990 and, (ii) the social value of potential future progress against various major categories of disease. The historical gains from increased longevity have been enormous, on the order of $4.4 trillion annually from 1970 to 1990. The reduction in mortality from heart disease alone has increased the value of life by about $2.3 trillion per year over the 1970 to 1990 period. The potential gains from future innovations in health care are also extremely large. Eliminating deaths from heart disease would generate approximately $75 trillion in economic value while a cure for cancer would be worth $73 trillion. Even a modest 1 percent reduction in cancer mortality would be worth about $775 billion. Unless costs of treatment rise dramatically with the application of new medical knowledge, these estimates indicate that the social returns to investment in new medical knowledge are enormous.
(I have converted all the estimates from $1992 in the original text to $2010, using the BLS calculator.) In brief, M & T argue that in the recent years of science-driven improvements in health care based in new medical knowledge have added many thousands of life-years to our collective longevity. Valuing these life-years in dollars we see that, among other innovations, "The reduction in mortality from heart disease alone has increased the value of life by about $2.3 trillion per year over the 1970 to 1990 period." For a benchmark, US 2010 gross domestic product is about $14 trillion. The message is that despite enormous waste in our health care spending, we are nevertheless getting an extraordinary return from our investments in science-based care. Although nothing is certain, it's reasonable to expect that continuing to invest in medical research will continue to bring significant returns.
As Harold describes, it's a breathtaking paper. Murphy and Topol are saying that thanks to science-driven health care our economy is producing not just tomatoes and Camaros, but also additional years of life. These additional years have stupendous value, but somehow we do not see it. The calculation is something like what the physicists did when they weighed the universe, found that there is vastly greater mass present than can be accounted for by ordinary 'visible' matter, and inferred that we are swimming in dark matter. There is a wonder in that finding, but there is also wonder in how they did it (they weighed the universe? HOW??).
So why is that value is hard to see? First, longevity is intangible. Second, most medical research is not particularly valuable. It's like the shipwrecked man putting notes in bottles and throwing them into the sea. The one that is picked up is extradorinarily valuable, the rest are just litter. But most importantly, the benefits of the investments in research that are valuable are realized over a long time span. It often takes decades to get a finding from the lab to the bedside. We are currently enjoying the benefits of investments in the development of cardiovascular disease treatments that were made decades ago.
And this leads to an ethical problem. The older you get, the less you have to gain from additional medical research, particularly in basic science. A discovery in fundamental biology made tomorrow will probably not affect the medical care that will be available in my life time. However, my generation is reaping extraordinary benefit from previous generations having diverted some of their savings to an investment that probably had little material benefit for them. (A small consequence of the M & T paper is that -- yet again -- I owe my father's and mother's generation a debt of gratitude, because they made this investment for me even though they were, collectively, much poorer than I am.) If we do not continue to spend on medical research, future generations will get at least as much longevity as we currently have, because medical knowledge is not consumed. But they may not experience the same gains in longevity that they would have gotten if we had, as our fathers and mothers did, diverted some of our consumption to research. We see this happening now with the NIH budget, and it will get worse.
There is a difficult argument here about justice for future generations. Do we (can we?) owe anything to people who do not even exist? Moreover, are we obligated to forgo our consumption, so that these unknown future persons will live longer than we will? Yet it nevertheless it feels wrong not to invest in a better medical future. It's as if we had been rescued from drowning, but in doing so the boat that rescued us was lost. We are asked to make a contribution to replacing it, so that others can be rescued in the future. We have no plans to go out on the water again. And so we decline.
This problem is everywhere. What is the duty of the elderly to pay for the education of toddlers whose maturity they will never see? Do people living now have to care if the carbon they emit now increases radiative forcing for the next thousand years?