(USA TODAY) -- Twice as many Americans will be eligible for cholesterol-lowering drugs, based on controversial new heart guidelines from two of the USA's leading cardiovascular associations.
The number of adults considered likely to benefit from statins will rise from about 15.5% today to 31%, according to the new criteria, developed by the American College of Cardiology and the American Heart Association, in collaboration with the National Heart, Lung and Blood Institute. While statins have been widely prescribed to reduce the risk of heart attacks, the new guidelines recommend that they also be considered for people at high risk of stroke.
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That advice could lead doctors to prescribe statins to millions more people, says Steven Nissen, chair of cardiovascular medicine at the Cleveland Clinic, who wasn't involved in the new guidelines.
"It's going to cause a huge conversation," says Mariell Jessup, president of the heart association. "It may be very controversial - which is fine. Controversy means discussion."
Authors of the new guidelines say they hope to get statins to more patients who need them, while avoiding unnecessary prescriptions for people unlikely to benefit.
The guidelines also call for doctors to work closely with patients to improve their diets and increase exercise.
Rita Redberg, a professor at the University of California-San Francisco, says she is concerned about exposing more patients to statins' side effects, which include an increased risk of diabetes, as well as muscle pain.
The average patient is likely to notice two major changes in the way that doctors manage their cholesterol, experts say.
For years, doctors often prescribed statins based on patients' cholesterol levels, especially their LDL, known as "bad" cholesterol. The new guidelines advise doctors to base their decisions on a patient's overall risk, rather than just their cholesterol. Nissen notes that even patients with normal cholesterol can have heart attacks.
"It's a huge, huge departure from the way that people have been thinking about cholesterol and heart disease," says Harlan Krumholz, a professor at the Yale School of Medicine. "Doctors today are obsessed with numbers."
The guidelines identify four high-risk groups who could benefit from statins: people with pre-existing heart disease, such as those who have had a heart attack; people ages 40 to 75 who have diabetes; patients ages 40 to 75 with at least a 7.5% risk of developing cardiovascular disease over the next decade, according to a formula described in the guidelines; 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.
These changes will help doctors to focus not just on "lab values," but on the whole patient, including a patient's weight, blood pressure, use of tobacco, diet, physical activity and other considerations, Krumholz says.
Doctors have focused heavily in recent years on using drugs to reduce LDL to certain benchmark levels: under 130 for most people; 100 for people at high-risk; under 70 for those at the highest risk, such as those who have just survived a heart attack. Doctors have raised or lowered medication doses to help patients meet these targets, Nissen says.
The new guidelines get rid of these targets, says Carl Orringer, a cardiologist at University Hospitals Case Medical Center in Cleveland. Instead, doctors are encouraged to put patients on doses proven to work.
The expert panel decided to eliminate these benchmarks because no one has ever tested them in a randomized, controlled trial - the gold standard for medical evidence, Nissen says. While studies clearly show that lower LDL is better, there's really no data to support using one cutoff or another.
Getting doctors to change their practices could be difficult, Nissen says.
That's because numbers are easy to understand, both for busy physicians and patients without a medical background. Having a "target" cholesterol in mind has seemed helpful to many doctors and patients, because it has given them goals to work toward.
About 600,000 Americans die from heart disease every year, according to the Centers for Disease Control and Prevention.
Contributing: Nanci Hellmich