The Myth of Prevention

In the raging debate over healthcare here in the U.S., there is one point on which everybody, from Newt Gingrich to Barack Obama, seems to agree: We should be spending more to prevent expensive diseases from striking in the first place, and thereby save society a great deal of money in the long term.

The most costly diseases to treat are chronic non-communicable diseases — adult-onset diabetes, heart conditions, kidney failure and the like — because they require more office visits and costlier drugs, administered over a longer period, than do infectious illnesses. And “lifestyle” choices — what people eat, drink and do with themselves — have a large effect on anyone’s probability of getting a chronic disease. If a nation can get people to quit smoking, snacking and lazing around, then that country will have fewer cases of chronic illness. With fewer chronically ill people in future decades, we will face lower medical costs. Win-win for everyone, right?

In fact, this argument is false. Its success is a nice illustration of what happens when people confuse the individual perspective (which comes naturally to the human mind, I think) with that of society as a whole (which is a harder subject to think about).

The problem is this: While it is true that obese people and smokers have higher medical bills per year, they also have fewer years. Money saved by preventing diabetes, stroke and heart attack in the 2020’s will have to be spent in the 2050’s on people who wouldn’t otherwise have lived. In fact, in the long term, the medical costs of longevity are higher than the costs of obesity and tobacco use. A computer model of future health spending in Holland, for instance, has found that the extra medical costs of smokers and obese people in Holland will be offset entirely by their tendency to die sooner than their fellow citizens. Even though the “bad” lifestyles cost society more per year, then, over a lifetime, it’s the healthy lifestyles that cost society most. “Obesity prevention may be an important and cost-effective way of improving public health,” writes Pieter H. M. van Baal of the Netherlands’ National Institute for Public Health and the Environment, who led the study, “but it is not a cure for increasing health expenditures.”

Another example: As Joshua T. Cohen, Peter J. Neumann and Milton C. Weinstein pointed out last year in the New England Journal of Medicine, the cost-saving value of any particular prevention measure “depends entirely on the particular intervention and the specific population in question.” Reviewing cost-benefit literature on 599 preventive health measures, they found that a large majority (among them an intensive anti-tobacco program for junior-high kids and the diabetes-screening program that targetted all 65-year-old men) did not save money.

This is not, of course, an argument against prevention programs. Helping people avoid pain, suffering and death is a worthy goal, in and of itself. Just don’t claim that it will save us from medical bankruptcy.