Statins are one of the most commonly prescribed drugs. This study suggests doctors rethink their use

A new study suggests that doctors may be prescribing statins—one of the most commonly prescribed drugs worldwide—to too many of their patients.

In the study, published in the Annals of Internal Medicine, researchers from the University of Zurich in Switzerland used a computer model to examine the benefits and harms of the cholesterol-lowering drugs. They found that statins may be overprescribed for the primary prevention of heart disease. That's because potential risks seem to outweigh the benefit for people whose 10-year cardiovascular disease risk is 7.5% to 10%—which is what the guidelines currently recommend.

The researchers said that prescribing for only those patients at higher risk thresholds would mean that millions of people would no longer be eligible for statin therapy. The study suggests that 15% to 20% of older adults should take statins—far less than the 30% to 40% of older adults who now fall within suggested medical guidelines. The researchers also said doctors should consider different recommendations based on sex, age group and statin type.

The study said it looked at risks not adequately considered in the medical guidelines.

"Some harms are mentioned, but it's entirely unclear how they were considered when coming up with the recommendations. In our approach we very explicitly considered the harms,” Milo A. Puhan, M.D., senior author of the study, told NPR. He cautioned there isn’t a one-size-fits all decision about statins.

The Swiss researchers evaluated the 10-year cardiovascular disease risk threshold at which the benefits of statins outweighed the harms, creating separate estimates for men and women in various age groups. They consistently found the harms—such as myopathy, liver dysfunction and diabetes—exceeded the benefits until the risk thresholds were substantially higher than recommended by current guidelines. For instance, among men age 70 to 75 with no prior cardiovascular disease events, benefits did not outweigh harms until the 10-year risk was above 21%.

Doctors may also want to consider what kind of statins they prescribe. The researchers found some statins were more effective, saying atorvastatin and rosuvastatin provided more benefit at lower risks than simvastatin and pravastatin.

So with studies leading to different conclusions about the appropriate point to begin a patient on statins, which recommendation is correct? Two doctors tackled that question in an accompanying editorial.

“Perhaps only the patient can say,” wrote Ilana B. Richman, M.D., and Joseph S. Ross, of the Yale University School of Medicine.

For instance: Is the patient willing to take a daily pill? Do patients favor a risk-averse approach in which potential harms are given greater weight than potential benefits or vice versa?

“The onus is on physicians to fairly summarize the evidence and guide patients through the decision-making process,” the two doctors wrote. This study can back up that decision-making as they talk about the pros and cons of treatment.