Thursday, December 18, 2014

False alarms and unrealistic expectations in preventive care

Shortly after we moved to Washington, DC ten years ago, my wife and I purchased a basic home security system, the kind with a programmable keypad, multiple door alarms and a motion sensor. The alarm has sounded about a dozen times since then. None of these times was a burglary actually in progress. On several particularly windy days, one of us forgot to lock the back door after leaving, and it blew open. Two or three other times, departing early for work, I accidentally hit "Away" on the keypad (arming the motion detector at the foot of the stairs) rather than "Stay," causing the klaxon to sound when my unsuspecting son or visiting mother-in-law came down the stairs later in the morning. We've also set off the fire alarm a few times while cooking. Although our security system cost little to purchase, we've spent well over $4000 in monitoring fees, a sum that could easily surpass the value of what we might lose in an actual burglary.

There are, of course, intangible benefits to having a home security system - peace of mind being the most important. But our peace of mind has been achieved at the substantial cost of temporarily diverting multiple municipal police and fire units, disturbing our neighbors, receiving inconvenient cellular phone calls from the monitoring company, and briefly traumatizing my 5 year-old son on his way to breakfast. All things considered, it's hard to argue that the benefits of this preventive measure have outweighed its cumulative harms.

I think about my home security system every time I'm asked to do a physical examination on an apparently healthy young adult. Although the periodic health examination is an established tradition in medicine, and probably builds trust and strengthens the doctor-patient relationship in preparation for future health crises, studies have shown that it doesn't help people live longer, or even better. The same may be said for many of the tests physicians routinely offer at these examinations - including blood pressure measurement (no benefit from treating mild hypertension) and diabetes screening (no benefit from nontargeted screening).

No doubt these routine examinations and tests (if normal), like my home security system, give patients peace of mind. And if patients had clear-eyed expectations of the small potential benefits of screening and preventive treatments, I would have no problem with continuing to do them. Unfortunately, a 2012 study in the Annals of Family Medicine showed that patients greatly overestimate the benefits of preventive interventions that primary care physicians commonly provide: breast cancer screening, colorectal cancer screening, and medications to prevent hip fractures and cardiovascular disease. In most cases, patients' "minimum acceptable benefit" (the lowest level of benefit that in their mind was required to justify the preventive intervention) far exceeded the actual benefit of the service established in randomized trials. Further, this study considered only the benefits of these services, and not the false alarms, which occur in more than 60 percent of women receiving annual mammography after 10 years.

Not only do inflated expectations of the benefits of preventive tests and treatments needlessly complicate shared decision making, they contribute to an environment where proposals to restrict screening tests of marginal benefit (such as the prostate-specific antigen test for prostate cancer) inevitably cause a political uproar. In the words of family physician and former U.S. Preventive Services Task Force member Steven Woolf:

If people are widely convinced that a screening test or drug is beneficial, confronting these beliefs can, if anything, engender suspicions about one's veracity and motives. Whether the messenger is one's physician, a health plan, or a government task force, attempts to set more realistic expectations about benefits, risks, and scientific validity are often taken as insensitivity to suffering, discrimination, or a pretext for cutting costs, rationing health care, or threatening personal autonomy. ... It is an increasingly difficult environment for the American public to receive, let alone absorb, undistorted scientific information from reputable bodies.

Unrealistic expectations therefore persist, surviving not only on misinformation but also by serving other purposes. For example, false beliefs meet the psychological needs of patients for hope and safety, as well as for action, agency, and a sense of control. They enable clinicians to feel they are making a difference; even physicians who know better order unnecessary tests to please their patients. False expectations fuel market demand for products, industries, and health delivery systems and can be fomented by misleading advertising. Confronting these expectations can not only dash hopes but potentially threaten profits, shareholders, clinical practices, industries, legislation, and political careers.

I recently had a testy social media exchange with an obstetrician-gynecologist who disagreed with my view that since cervical cancer screening is needed only every 3 to 5 years, and ovarian cancer screening is useless and potentially harmful, there is no good reason to do annual pelvic examinations in women at low risk for sexually transmitted diseases. However, a recent survey of U.S. gynecologists found that overwhelming numbers (including, presumably, this particular Ob/Gyn) continue to do these examinations despite the absence of proven health benefits. In my view, the only clear benefit (aside from "peace of mind") is financial - doctors can charge more for physicals that include a pelvic examination, payers will pay for them without question, and medical offices then have an easier time keeping their doors open.

Preventive health care has positive effects if offered to appropriately selected and informed patients. But the massive structure of "routine" preventive care, built upon a rotten foundation of false alarms and unrealistic expectations, only serves to increase harms and health care costs. It should be a New Year's resolution of conscientious physicians and policymakers everywhere to help people understand the difference.


This post first appeared on Common Sense Family Doctor on December 22, 2012.