In 2013, a combined panel of cardiology and lipid experts under the aegis of the American College of Cardiology and the American Heart Association (ACC/AHA) published revised recommendations for candidates for statin therapy to reduce the risk of cardiovascular events (heart attack, stroke or sudden death due to coronary artery disease: CVD). Rather than focusing, as always before (e.g. the ATP-III published in 2003) on lipid levels, LDL especially, the new report emphasized overall heart risk using other parameters including age, weight, blood pressure, and diabetes. For anyone with a predicted risk over a 10-year period of 7.5 percent or more, statins were recommended. Many experts, as well as ordinary folks, believed that the new advisory would lead to many more millions of Americans being put on a statin drug, and many were skeptical about the wisdom of this concept.
Now a new reassessment of the validity of the revised recommendations has been published in JAMA. Entitled Guideline-Based Statin Eligibility, Coronary Artery Calcification, and CVD Events, the somewhat surprising conclusion of the authors is that rather than being overly-expansive, those recommendations should be expanded even more to more effectively reduce the risk of CVD events.
The group, mainly based at Mass. General Hospital in Boston and the Harvard Medical School, used data from participants in the long-term Framingham Study and its offspring and third-generation cohorts; CT scanning for coronary artery calcification was performed on all participants between 2002 and 2005, and all were followed for a median of 9.4 years. The endpoints were incident CVD: new onset of MI (heart attack), stroke or CAD-related sudden death.
Two-thousand three-hundred forty-five subjects, none on statins, were evaluated. Their average age was 51, and 56 percent were female. As compared with the fraction eligible for statin therapy by the ATP-III criteria (14 percent), The ACC/AHA criteria identified 39 percent recommended for statins.
Roughly 25 percent of Americans over age 45 now take a statin. The authors assert that by widening the range of people who should be taking statins as per the ACC/AHA revision, between 40,000 and 60,000 CVD incidents might be prevented over the next decade. Recently, however, more evidence of the statin class potential for adverse effects, in the form of a slight but definite increased risk of diabetes, and an even smaller risk of muscle abnormalities, might temper somewhat the eagerness of medical providers to put just about everyone on a statin. And the data supporting their efficacy in secondary prevention reducing the risk of a second or third event is far stronger than the evidence of benefit in primary prevention.