Statins Underprescribed To Patients At Higher Risk of Heart Disease

Armen Hareyan's picture

Heart Disease and Statin

The use of cholesterol-lowering drugs known as statins to reduce the risk of heart disease has exploded in recent years, but a new Stanford University School of Medicine study shows that doctors are prescribing them in only half of their visits with patients who would benefit most from them.

Based on the findings, the researchers say physicians should be more aggressive in investigating statin therapy for patients with a high or moderate risk of heart disease, and that patients should ask to have their cholesterol levels checked regularly.

The findings, published in the May 31 issue of the Public Library of Science-Medicine, come at a time when many Americans are still reeling from recent reports that some prescription drugs, including the painkiller Vioxx and postmenopausal hormone therapy, were overprescribed to patients who had little to gain from them.

"You have to look at drug therapy on a case-by-case basis. We have many situations where drugs are misused or overused," said lead author Jun Ma, MD, PhD, research associate at the Stanford Prevention Research Center. "In this particular case, although we did observe some inappropriate use of statins in low-risk patients, the predominant problem appears to be underuse in higher risk patients."

Since their introduction 17 years ago, statins have become the most prescribed class of drugs in the United States, with more than 126 million prescriptions filled in 2004. Statins reduce the level of cholesterol produced by the liver while boosting the liver's ability to remove LDL cholesterol, the so-called "bad" cholesterol, from the blood. High LDL cholesterol levels increase the risk for heart disease. Each year, more than half a million people die from heart disease, making it the No. 1 killer among both men and women.

Randall Stafford, MD, PhD, associate professor of medicine at the Stanford Prevention Research Center and senior author of the study, said there are reliable methods of identifying patients at high risk for future heart attacks as well as effective strategies for lowering that risk, mainly through smoking cessation, a healthier diet, more exercise and medications such as statins. "The problem is that we have not been effective at turning this evidence into practice," Stafford said.

Although previous studies have tracked statin use on a smaller scale, Ma said this study is the first to examine how statin therapy varies according to the risk of heart disease among U.S. outpatients.

The researchers examined two national databases that tracked outpatient visits to hospitals and physician offices between 1992 and 2002, and the types of medications that were either continued or prescribed during those visits. They then correlated the results with the number of patients who had been diagnosed with high cholesterol levels and whose risk for heart disease was categorized as either high (already having either heart disease, stroke, peripheral vascular disease or diabetes), moderate (having two or more risk factors for heart disease, such as high blood pressure, obesity and cigarette smoking) or low (no more than one risk factor).


"We looked at people who were likely to benefit the most from these drugs and we found a wide therapeutic gap," Ma said.

Among patients with high cholesterol in the moderate- and high-risk groups, the researchers found that fewer than half of the patient visits were associated with statin use in 2002. Among the high-risk group, statin use rose from 14 percent of patient visits in 1992 to 50 percent in 2002. For those at moderate risk, statin use went from 9 percent of patient visits in 1992 to 44 percent in 2002.

While encouraged that statin has increased, "it's disconcerting that the magnitude of the increase is much smaller than expected," Ma said. "The rate of use falls significantly short of the latest recommendations."

Ma also noted that although statin use is greatest among the high-risk group, physicians should be more aggressive in looking at statin therapy for moderate-risk patients. "Prevention is key for delaying the onset of cardiovascular disease. If we start intervention early enough, we can delay the progression of the disease and reduce the health-care costs overall," she said.

The study also noted that less than half of the moderate-risk patients were counseled about changes in their diet and exercise that could decrease their risk of heart disease. "Lifestyle change is fundamental not only to keep your risk for heart attacks low, but also to give you better health overall," Ma said.

The researchers are careful to point out that statins aren't appropriate for all patients. "They have to be prescribed for the right reasons and for the right groups of patients. For any drug therapy, you have to balance the risks against the benefits," Ma said, adding that physicians should categorize patients according to their underlying risk of heart attacks and then treat the higher-risk patients the most intensively.

The study was funded by an unrestricted grant from Merck Co., a pharmaceutical company that manufactures the statins Zocor and Mevacor, and by the Agency for Healthcare Research and Quality.

Co-authors of the paper include Niraj Sehgal, MD, a former postdoctoral scholar at Stanford who is now an assistant clinical professor of medicine at UC-San Francisco, and John Ayanian, MD, associate professor of health-care policy and of medicine at Harvard Medical School.


Stanford University Medical Center integrates research, medical education and patient care at its three institutions - Stanford University School of Medicine, Stanford Hospital