Catching up wit h the news

I'll get back to the deep epistemological thoughts soon, but a couple of noteworthy studies have come out over the holidays, in the general vein of less is more.

First, I'll bet your doctor has you come in for an annual checkup, assuming you are fortunate enough to have health insurance. Don't bother. Based on a systematic review, some Danish folks whose names I won't repeat because I don't know how to make the "O" with a / through it conclude that "General health checks [i.e. checkups] did not reduce morbidity or mortality, neither overall nor for cardiovascular or cancer causes, although they increased the number of new diagnoses. Important harmful outcomes were often not studied or reported." In other words, they don't make you any healthier or make you live any longer, they just get you more diagnostic labels. And, obviously, cost money. Maybe we wouldn't have such a shortage of primary care providers if they weren't busy wasting their time and ours.

See the doctor if you have a good reason to, such as symptoms you're worried about or you need a certificate or something. And of course, if you have a chronic disease that requires ongoing management. Otherwise, find something better to do.

And yet another analysis that should prompt second thoughts about screening mammography. Basically, based on data from the U.S. cancer registry called SEER, Bleyer and Welch conclude that somewhere close to 1/3 of the cancers found by routine screening would never have caused clinically significant disease; and the vast majority of the rest could have been successfully treated even if they were diagnosed later, after a palpable lump or other symptoms appeared. The basis of this conclusion is essentially that after screening became widespread, the rate at which early stage cancers were diagnosed went way up, but diagnosis of late stage cancers went down only a tiny bit. Simple arithmetic tells you that most of those cancers diagnosed by screening would not have ended up being diagnosed at a late stage. Also, this means that something like 70,000 women a year are "overdiagnosed," i.e. they are told they have breast cancer and treated for it, even though nothing bad would ever have happened to them if the "cancer" had not been found.

Again, I'm not a real doctor and I'm not giving medical advice. Certainly if your mother or sister had breast cancer, if you've had estrogen therapy, if you have never had children, you are at higher risk and have a stronger argument for getting a screening mammogram. But make your own decision -- don't let anybody pressure you to do it.

That said, this finding is not anti-medicine. Au contraire. The death rate from breast cancer has fallen a lot in the past two decades. But that is because of better treatment. Advances have been incremental so they haven't been much noticed, but they have been substantial. The contribution from screening to the lower death rate, if any, must be quite small. And by the way, better treatment is probably why screening doesn't turn out to be so valuable after all -- catching it very early isn't as important any more.