There's good news . . .

and, of course, bad news. The good news is that yet another study confirms the general observation that the risk of stroke has been steadily declining in the U.S. (Abstract only to the unwashed.) This is based on the Framingham study cohort, which is not even close to being representative of the U.S. population, so this is mostly good news for middle class white folks.

But what is really interesting about it is why this appears to have happened. The prevalence of smoking in this population declined over the decades, which is probably the most important factor. More people had their blood pressure and LDL cholesterol controlled. These trends were sufficient to overcome the greater prevalence of overweight and obesity, and of Type 2 Diabetes. Since those bad trends are continuing, I would personally fear that the risk of stroke will start to increase again some time soon.

But that's not the bad news I was referring to. It's the age-specific risk of stroke that has been decreasing. The life-time risk has declined very little (actually the decline is not statistically significant in this study, by the conventional definition), because people are living longer. You're less likely to have a stroke in your 50s or 60s than your parents, but you're about as likely to have one eventually. Whatever happens with obesity and diabetes in the future, the aging of the population will continue, and the prevalence of stroke-related disability is bound to increase, even if the age-adjusted risk continues to decline. It doesn't help that when people have strokes when they are older, they are much less likely to recover function. So we continue to have more and more older people with disabilities, even as we continue to improve population health by most measures.

This is a big problem for those of us affected by it directly. (Disclosure alert: I'm among them. As I have revealed here previously, my father has severe disability related to stroke and dementia.) It's also a big problem for society -- for taxpayers, and for our future allocation of resources. Thousands of adult day care centers have sprung up around the country in just the past decade or so. We need more assisted living facilities, more rehabilitation facilities, more nursing homes. Care for the frail and disabled elderly will consume more and more of our wealth, both private and public; more of our individual time, effort and emotional investment; more of our public policy making energies.