Memo to Ezra Klein: How Not to Cite a Health Study

Question for Ezra Klein. Why are you getting your health data from the Cato Institute? It was headache-making for me to read the progression from a rather limited study. . .

Rational decision-makers will take into account forecasts of longevity and quality of life in making their work and savings decisions. Public policy must account for this as well. Every additional year of life after age 65 is associated with about $15,000 of social security and medical care spending, and years spent disabled result in substantially greater medical spending than years spent without disability. . . .

. . . to one sweeping generalization . . .

Americans are getting healthier in spite of a little extra flab.

. . . to another. . .

Americans are actually becoming substantially healthier, even as our waistlines expand.

Let’s first review the quantitative results from the Cutler, Glaeser and Rosen study, and then look at where the authors might have overstated their conclusions a bit based on those findings. First, the results (from the summary):

For the population aged 25-74, the 10 year probability of death fell from 9.8 percent in 1971-75 to 8.4 percent in 1999-2002. Among the population aged 55-74, the 10 year risk of death fell from 25.7 percent to 21.7 percent. The largest contributors to these changes were the reduction in smoking and better control of blood pressure.

So, there’s a reduction in overall mortality, and it might be related to people smoking less and better blood pressure medication (I’m fairly sure people aren’t controlling their blood pressure better using exercise and diet. . . ). However, the authors don’t make clear how this translates to:

Examining these factors as a whole, we show significant improvements in the health risk profile of the U.S. population between the early 1970s and the early 2000s. Reduced smoking, better control of medical risk factors such as hypertension and cholesterol, and better education among the older population have been more important for mortality than the substantial increase in obesity.

Reduction in mortality doesn’t translate directly to “significant improvement in the health risk profile”. For example, the authors didn’t go into why they feel we’re getting healthier if the overall prevalence of diabetes is increasing over time, and if we’re spending more to treat it. I have to wonder if Ezra and the Cato Institute are implying that we’re getting healthier because we spend more money to keep at bay a lifestyle-related chronic degenerative disease. Shades of Mad Hatter economics. . . .

While the underlying purpose for the study isn’t mentioned in the paper, it is interesting to note that it was funded by the Social Security Administration. I have to wonder if it’s intended to figure out how much of an impact there’s going to be to the Fund from the reduced mortality. For example, the Centers for Disease Control have reported:

At least 80% of seniors have at least one chronic condition, and 50% have at least two. These conditions can cause years of pain, disability, and loss of function. About 12 million seniors living at home report that chronic conditions limit their activities. Three million older adults say they cannot perform basic activities of daily living, such as bathing, shopping, dressing, or eating. Their quality of life suffers as a result, and demands on family and caregivers can be challenging.

And, the introduction of the Cutler, Glaeser and Rosen study does state:

Every additional year of life after age 65 is associated with about $15,000 of social security and medical care spending, and years spent disabled result in substantially greater medical spending than years spent without disability.

So, is the Cutler, Glaeser and Rosen study is one piece of information about the impact of increased longevity on social security and medical spending? The study doesn’t really say that, but it’s not an unreasonable inference. But it is a broad overstatement to say the Cutler, Glaeser and Rosen paper is evidence that we’re getting healthier even as we get fatter.

It’s no surprise to me that the Cato Institute would go there. However, I am surprised that Ezra Klein would fall for it.