Medical Studies

“The problem is that we don’t know what we are doing”

According the CIA World Factbook, life expectancy at birth in the U.S. has reached nearly 78 years old. In Singapore, Hong Kong and Japan, life expectancy is over 81. One wonders, however, how much of the increase in longevity in recent years is due to rising incomes, better diet and exercise, and how much is due to medical advances.

Some experts would say that the latter has contributed little. Dr. David Eddy claims in a Businessweek article (“Medical Guesswork“) that only 20-25% of medical procedures have proven to be effective. In Dr. Eddy’s words “The problem is that we don’t know what we are doing.” The article also gives the following anecdote:

“With a groundbreaking computer simulation, Eddy showed that the conventional approach to treating diabetes did little to prevent the heart attacks and strokes that are complications of the disease. In contrast, a simple regimen of aspirin and generic drugs to lower blood pressure and cholesterol sent the rate of such incidents plunging…

The message got through. Three years later, Kaiser is in the midst of a major initiative to change the treatment of the diabetics in its care. “

Dr. Eddy isn’t the only expert to voice concerns that much medical care may be ineffective. Discover magazine (“Dialogue“) has an interview with Dr. Nortin Hadler. Dr. Hadler claims that bypass surgery is never appropriate. His explanation of why the surgeries are still conducted is the following:

“Money. Interventional cardiology is what supports almost every hospital in America—it’s an enormous part of our gross domestic product. Every year in this country we do about half a million bypass grafts and 650,000 coronary angioplasties, with the mean cost of the procedures ranging from $28,000 to $60,000.”

Dr. Hadler’s main determinate of life expectancy is also interesting:

“With regard to socioeconomic status, the central question relates to relative wealth—in other words, the smaller the income gap in a given area, the better the longevity. Where the income gap is larger, the poor die sooner. These are powerful associations. The answer does not lie in modern medicine but in modern society.”

This association may (or not) be true for developed countries. Anecdotally, it does hold in countries like Cuba where individuals are poor ($3,300 GDP/capita), but inequality is low. Life expectancy in Cuba is only 0.44 years behind that of the U.S. I believe, however, that in general increasing GDP/capita generally increases life expectancy in developing countries even if inequality increases.

Further, I posit that wealth is highly correlated with good health, but it is difficult to tell if these relationships are causal. Does good health allow a worker to make more money during their lifetime, or does more wealth allow a worker to purchase better health care? The direction of causality is indeterminate.