What’s in a number? That’s a complex question for doctors trying to help patients lower their cholesterol levels.
Controversial new recommendations for treating cholesterol, released last month by the American Heart Association and the American College of Cardiology, represent a major departure from physicians’ usual approach.
Robert Robbins, M.D.,
Traditionally, doctors have focused heavily on numbers to determine which patients should be prescribed statin drugs to lower their cholesterol, especially their “bad” cholesterol, known as LDL. The long-accepted goal was to help patients achieve certain LDL benchmark levels: under 130 for most people; 100 or lower for people at high risk; and 70 or lower for those at the highest risk – for example, people who have survived heart attacks. Doctors raised or lowered medication levels as needed to help patients reach these benchmarks.
But the new guidelines advise doctors to consider a patient’s overall risk, not just their cholesterol numbers, when deciding whether to prescribe statins.
Doctors now are advised to look at the big picture, including the patient’s body weight, blood pressure, diet, physical activity and blood sugar levels, smoking history, along with their cholesterol levels. Based on this new approach, twice as many Americans will be eligible for cholesterol-lowering drugs, rising from 15.5 percent today to 31 percent according to the new criteria.
Dr. William Zoghbi, director of the Cardiovascular Imaging Institute at Houston Methodist Hospital and recent past president of the American College of Cardiology, says the new guidelines are intended to focus attention on achieving a healthy diet and active lifestyle. Instead of focusing on “lab values,” the guidelines encourage doctors to focus on the whole patient.
To accompany the new guidelines, the American Heart Association and American College of Cardiology have developed a “risk calculator” doctors can use to identify patients whose risk of suffering either a stroke or a heart attack over the next 10 years is judged to be at least 7.5 percent. These patients can reduce their risk by taking a low-dose statin, the new guidelines say.
Furthermore, the guidelines identify four high-risk groups who could benefit from statins: people with pre-existing heart disease; people ages 40 to 75 who have diabetes; patients ages 40 to 75 with at least a 7.5 percent risk of developing cardiovascular disease over the next decade as determined by the risk calculator; and patients with the sort of super-high cholesterol that sometimes runs in families, as evidenced by an LDL of 190 milligrams per deciliter or higher.
Zoghbi, who led the organization during this guideline evaluation, says clinical trials show that patients with high-risk calculations should be treated with high doses of statin drugs, while patients with lower risks should have lower doses.
Some of the nation’s cardiologists are challenging the new recommendations and say the risk calculator was developed using unreliable data on Americans’ health. Others defend the calculator, saying it underwent multiple reviews that were internally and externally validated.
Many physicians, including Dr. James Willerson, president of the Texas Heart Institute, say they will continue urging their patients to shoot for an LDL level below 100.
Willerson says he would not presume to speak for either the American Heart Association or the College of Cardiology and how they determined these new guidelines, but that giving patients a targeted number to strive for enforces the efforts they put into lowering their cholesterol, including lifestyle changes and taking medication.
Statin drugs are among the most important medicines developed in the past hundred years, Willerson says.
Statins block the liver from producing cholesterol. They lower LDL and a form of fat named triglycerides, and have a mild effect in raising HDL, the “good” cholesterol. LDL can build up in the walls of your arteries and form plaque, which restricts blood flow and can lead to heart disease. HDL is thought to help remove bad cholesterol from the body.
Whether your physician wants to aim at an LDL target or not, patients must be pro-active in their care. See your doctor, get a blood test, know your cholesterol numbers, calculate your risk factors and, if needed, take medication, lose weight, exercise, and by all means, don’t smoke.
Risk calculators from the American Heart Association are available at What's My Risk?