Over-Diagnosed: Making People Sick in the Pursuit of Health is a physician researchers’ perspective on the state of medical practice in the United States. It was published in 2011, so some of the information is dated. But the fundamental questions raised by H. Gilbert Welch, M.D. and his co-authors are vital medical ethics and practice concerns.

To simplify a complex set of topics, Welch encourages patients and even physicians to think carefully about the cost versus benefit of early detection and treatment. He’s not against medical care. In fact, far from it. But he says that we try to “get ahead” of illness, and thus treat patients before they have actual symptoms of that illness. And that may or may not end up making a difference in their long-term health. He believes that sometimes it can actually do harm.

Main Topics

Welch starts out by discussing conditions like high blood pressure, high cholesterol, and osteoporosis. In this case he focuses on the way disease thresholds get lower all the time. He says this means more people are more medicated for longer, but that we have little proof it prolongs their lives. If the early treatment doesn’t prevent potential events (heart attack, stroke, hip fracture), then patients may be over-diagnosed.

The largest section of the book discusses several types of cancer, particularly those with more robust screening tools. The distinction between screening and diagnostic options is key here. When patients have no symptoms, tests screen them for early evidence of disease. On the other hand, testing is considered diagnostic when the patient has concrete symptoms. Welch focuses on how and why medicine offers early cancer screening. And whether the corresponding benefits are worth the potential risks. If they aren’t, then people are over-diagnosed.

Welch also reviews the role of improved DNA testing in extreme early diagnosis, and possible over-diagnosis. He’s clearly not a fan of patients sending their saliva off to a company who then tells them their genetic risk of developing certain diseases or conditions. Still, he goes into significant detail explaining how these risks are determined. Considering your genetic risk a motivation to start preventative early treatment can also lead to over-diagnosis.

My conclusions

This book is full of statistics and percentages. The author humanizes the issue with a few real-life stories, but mostly he sticks to “just the facts, ma’am.” And after about a half hour, I had trouble remembering if a given risk was 2% or 20%. Perhaps that’s because I listened to the audiobook, which means I’m likely to be multi-tasking. Or perhaps it’s just the nature of the topic and Welch’s writing style.

If you like voluminous details in your medical or science books, then this one’s for you. And yet, Welch writes for the layman. He explains medical concepts with a good balance of jargon and definitions, and keeps it fairly simple for us non-professionals.

According to Welch, patients need to understand three things:

  1. Their potential risk of developing a certain disease, particularly with no current symptoms
  2. How much treatment potentially reduces their risk of developing that disease
  3. What are the potential downsides or risks of a treatment (medical, financial, and otherwise)

If you enjoy a good book about medical science and the U.S. healthcare system, give Over-Diagnosis a go.

Pair with Your Medical Mind: How to Decide What is Right For You by Jerome Groopman and An American Sickness by Elisabeth Rosenthal, for a more systemic perspective.