a paper in the American Journal of Public Health, a well-respected scholarly publication in the field, caught my attention.1 The paper reported how health economists, using well-validated instruments, examined the state of population health in the United States and how population health changed from 1987 to 2008. They took into consideration not just mortality and morbidity, but also quality of life, which is an essential measure of health in developed countries like ours.This week,
It has been argued that the extension of municipal sewer systems in the early 1900s, blocking the transmission of age-old infectious diseases, led to the greatest amelioration in public health in modern history. Today, it is not that easy to improve health status. Because of our higher standards, any measure of the quality of life must take into consideration the ability to live independently. The continuance of self-care, good cognitive function, and low chronic pain levels are important health attributes that need to be considered. All these elements were factored into the paper by Stewart and colleagues to estimate trends in an indicator that health economists call QALE (quality-adjusted life expectancy).
And here is the good news. From 1987 to 2008, QALE increased for all the demographic groups considered: men, women, whites, and blacks. Today, a person who is 25-years-old is expected to live an additional 2.4 quality-adjusted years when compared with1987, while a 65-year-old today gained 1.7 quality-adjusted years. These are significant numbers, and I was very pleased to see them.
According to the researchers, the determinants driving this health improvement were overall decreased mortality, followed by improvement in energy, depressive mood, self-care, and pain. However, the researchers also noted that these health advances could have been even greater if changes in obesity had not wiped out the gains we've made through reductions in smoking. This is indeed sad, and underscores the disease burden that the obesity crisis is inflicting on adolescents and adults. Another depressing finding is that our nation still faces significant health disparities. Still today, white women show the highest QALE values, while black males show the lowest, with a gap that can be bigger than five quality-adjusted years.
So, what does biomedical research have to do with this finding? How do we know if it is really our research that is moving the dial on human health?
For the public, and perhaps even for cell biologists, these may seem like simple and naïve questions, but—trust me—when you dig a little deeper, they quickly become much more difficult to answer. Before I venture a little deeper into the issue, let me make sure that I state the most important fact—it is imperative for a country to invest taxpayer money in basic research because research is the perfect example of what economists (I am married to a good one) call public good. It does not make sense for the captain of one ship to pay the total costs of building a lighthouse on a perilous coast. Other captains on other boats will see the light, and the fact that one boat takes advantage of the tower does not preclude another one for also using its benefits. This is called a condition of non-exclusivity and non-rivalry. If you think about it, basic scientific research (but not necessarily industrial research) is pretty much all in this category. Therefore, these are perfect investments for government. Without public money, no one would cough up the money for a lighthouse, simply because it would not be a good deal for any single user or potential user.
So, let me ask the question again—what have been the effects of public investments in science on human health? Are the gains that Stewart et al. attributable to the work that ASCB members do at the bench by studying the Golgi apparatus or lipid membranes? The answer is certainly yes, but it is not as simple as you may instinctively think.
The researchers did not address the question in this paper but there is a robust literature on this issue. Previous work by David Cutler shows that in the U.S. we gained seven years of life expectancy from 1960 to 2000.2 Three main factors account for this success: reduction in cardiovascular disease mortality, infant mortality, and cancer mortality. Reduction in mortality due to cardiovascular disease accounts for 70% of these seven extra years. It is the big winner. Cutler matched the results of clinical trials to observed mortality declines and attributed as much as two-thirds of this reduction to medical advances because of better treatment of acute conditions and better medications to manage the disease. One hundred percent of infant mortality reduction is attributable to medical advances and about two thirds of the decrease in cancer mortality is attributable to better screening and treatment. So, Cutler concludes that, conservatively, about half of the gains in health that we enjoy derive from medical research.
This is quite remarkable, and indeed none of this would be possible without the basic science that is at the basis of these changes. This science is funded by taxpayers, mostly through the National Institutes of Health. This is the science that is being delayed and stifled by sequestration and other nonsensical policies, which are compromising not only the present but the future health of the nation and of the world. According to the data presented above, if we cut biomedical science, we diminish the gains that we made because of the synergistic effects that exist between research and various services that affect health. Most of all, by foregoing biomedical research, we will fail to adapt to new challenges of emerging and re-emerging diseases. What is equally clear is that we can't stand still, or even worse decrease our investments in science, as we are doing now. Imagine the day when a paper in the American Journal of Public Health reports that our QALE numbers have fallen because we failed to treat or prevent Alzheimer's disease or because we have not found a way of colonizing the human gut with the beneficial microflora that could reduce the obesity epidemic. I don't even want to think about reading such a paper, but it seems that our policy makers have started drafting it.
1Stewart ST, Cutler DM. Rosen AB. (2013). US Trends in Quality-Adjusted Life Expectancy From 1987 to 2008: Combining National Surveys to More Broadly Track the Health of the Nation. Am J Public Health. doi:10.2105/AJPH.2013.301250
2Cutler DM, Rosen AB, Vijan S. (2006) The value of medical spending in the United States, 1960-2000. N Engl J Med Aug 31; 355(9), 920-7.