Predictors of residual cardiovascular risk in patients on statin therapy for primary prevention.

Background: Low-density lipoprotein cholesterol-lowering therapy is an important aspect of primary prevention of cardiovascular disease (CVD). Statins are the most widely used drug therapy for achieving low-density lipoprotein goals based on an individual's 10-year risk. However, substantial risk of CVD events still exists even when a person is on statins. We sought to explore the predictors of future CVD events in individuals on statins with no pre-existing CVD.

Methods: The analysis was done on subjects who were on statins (n = 919) at baseline in the Multi-Ethnic Study of Atherosclerosis limited access dataset from the National Heart, Lung and Blood Institute. The primary outcome variable was all-cause CVD events (n = 67). Multivariate regression Cox proportional hazard analysis was done to identify potential independent predictors of all-cause CVD.

Results: Our cohort consisted of 47% males, with a mean age of 66 ± 9 years. Sixty-seven participants (7.3%) experienced CVD events during a mean follow-up of 4.4 years. A higher coronary artery calcium score, homocysteine levels, waist circumference and a lower large arterial elasticity index were identified as independent predictors of CVD events.

Conclusion: Homocysteine, waist circumference, coronary artery calcification and the large artery elasticity index appear to be the major independent predictors of CVD events in individuals on statins with no pre-existing CVD. In addition to emphasizing weight loss, alternative approaches beyond lipid reduction may need to be explored to better characterize and attenuate the residual risk in subjects on statin therapy for primary prevention.