Statins Reduce Risk Of Heart Attack And Stroke In Those Without Heart Disease

Statins have been shown to reduce death and other negative outcomes associated with heart and cerebrovascular disease among those who already have these conditions, according to background information in the article. It is less clear whether these medications benefit those without cardiovascular disease. Current national treatment guidelines recommend the use of statins in these patients based on their cardiovascular risk profile and LDL-C or "bad cholesterol" level. For patients without cardiovascular disease and with normal LDL-C levels, statins are recommended only for individuals with diabetes or with two or more other cardiac risk factors that raise their 10-year risk of a heart attack or other heart event to at least 10 percent.

Paaladinesh Thavendiranathan, M.D., M.Sc., University of Toronto, Ontario, and colleagues analyzed the results of seven previously published clinical trials that assessed the benefits of statins in a total of 42,848 patients, 90 percent of whom had no history of cardiovascular disease. In each study, patients were randomly assigned to receive either statins or another form of care and were followed for at least one year, at least 100 major cardiovascular events occurred and 80 percent or more of the participants did not have cardiovascular disease.

In total, 21,409 patients in the trials took statins and 21,439 were assigned to placebo. The average follow-up period for the studies ranged from 3.2 to 5.2 years; average age of the participants ranged from 55.1 to 75.4 years; and the proportion of men included ranged from 42 percent to 100 percent. In patients on statin therapy, there were 924 major coronary events such as heart attack compared with 1,219 among those in control groups--a 29.2 percent reduction in risk. Major cerebrovascular events, including stroke, occurred in 440 patients taking statins and 517 controls, a 14.4 percent lower risk. Statin treatment was also associated with a 31.7 percent reduction in risk for non-fatal heart attacks and a 33.8 percent reduction in the number of revascularization procedures, which restore blood flow and include angioplasty and bypass surgery. There were no statistically significant differences between the statin and control groups in the rates of patients who died from cardiovascular disease or from all causes.

Assuming that individuals not taking statins have a 5.7 percent chance of having a major heart event over a 4.3-year period, statins can reduce that risk to 4 percent, the authors write. "Therefore, 60 patients would need to be treated for an average of 4.3 years to prevent one major coronary event." Similarly, 268 patients would need to be treated to prevent one stroke or other major cerebrovascular event; 61 to prevent one non-fatal heart attack; and 93 to prevent one revascularization procedure.

Statins are expensive and other therapies also may work to reduce risk, the authors conclude. "Therefore, even though universal lipid-lowering therapy appears attractive, especially in an intermediate-risk primary prevention population, further studies are needed to clarify the cost-effectiveness of therapy in this group."