When Benjamin Franklin said "An ounce of prevention is worth a pound of cure," he wasn't talking about taking Lipitor to keep from having a heart attack. In fact, he wasn't talking about health at all. No, he was interested in keeping people from burning their homes down by being careless with hot coals in dwellings with wood floors. So who is following in Franklin's footsteps? It isn't the American Cancer Society when they tell you to sign up for the joy of colonoscopy at age 50. No, it's Smokey the Bear.
There are many things we hear all the time in discussions of ways to promote good health that drive me bonkers because I think we should be precise in our use of language. So, for example, it irks me every time I hear about mammograms and "prevention" of breast cancer. That tells me people don't understand the difference between prevention and early detection.
But I digress, so let's focus. What do we know about prevention? Or maybe the better question is what do we think we know about prevention? We have some pretty fair ideas about healthful diet and what we should eat to lower our risk of developing cardiovascular disease and some forms of cancer. There is reasonably good evidence, for example, that trans fats are associated with (and probably contribute directly to) arteriosclerotic cardiovascular disease and colon cancer. Diets lower in saturated fats and refined sugars are good. Regular exercise has an abundance of scientific evidence to support the belief that it reduces the risk of heart attack and stroke, and probably dementia, too. The scientific literature on the relationships among diet, exercise, prevention of disease, and promotion of health is vast and fascinating. I often quibble over whether the evidence is merely circumstantial and demonstrates an association without proving cause and effect, but a big pile of circumstantial evidence may be enough reason to change behaviors. And some of the evidence is based on more rigorous studies that really do show causality.
I am more skeptical when it comes to medical interventions to prevent disease and promote health. Really, you may be asking? A doctor expressing skepticism about the value of medicine? As one controversial political figure likes to say, You Betcha!
You see, for every medical intervention there are risks and benefits, and one must always know them, weigh them, and find the right balance. So, while there are studies that show some people can lower their risk of premature death from heart attack by taking a statin (such as Lipitor), these drugs are not without side effects, occasionally serious ones. And the risk-benefit balance is not the same for every patient. People at high risk for an adverse health outcome are typically more likely to benefit from an intervention, while those at lower risk may be more likely to be harmed by the intervention.
There is a long litany of issues in prevention of disease and promotion of health about which it is easy to find differences of opinion and swirling controversy. These include treatment of high blood pressure (specifically treating milder elevations), the use of drugs to lower cholesterol, tight control of blood sugars in diabetics, and the use of screening tests for early detection of prostate and breast cancers, just to name a few.
Give me enough free time to research the details on which I may be a bit fuzzy, and I could write a book about this stuff. But that won't happen, because I'll never find an agent good enough to persuade a publisher to give me an advance that would cover my living expenses, so I must go on practicing medicine to support myself. But that's OK, because someone else has already written the book. Actually, there are more than just one, but earlier this year one was published with the title Overdiagnosed: Making People Sick in the Pursuit of Health (first author H. Gilbert Welch). Dr. Welch makes a compelling case that we can do a lot of harm by looking for "abnormalities" in our anatomy and physiology that may not be "disease."
The best book in this area by a non-physician was published in 2007 by award-winning journalist Shannon Brownlee: Overtreated: Why Too Much Medicine is Making Us Sicker and Poorer. Brownlee's work is especially illuminating if you are interested, as I always am, in how so many of the things that go on in our health care system seem to be driven more by the profit motive than by what is best for patients.
What does all this mean for you? When a doctor recommends an intervention intended to prevent disease, detect it at an earlier, more curable stage, or in any other way promote better health, ask about the downside. What is known about risks relative to potential benefits? And not just for populations of patients, but for you as an individual, because the risk-benefit analysis is different for every person. If your doctor doesn't seem to know how to answer that question - or, worse yet, is dismissive - do your own research or find yourself a better doctor.
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