The HDL cholesterol/apolipoprotein A-I ratio: an indicator of cardiovascular disease

In multiple studies, the HDL cholesterol (HDL-C) concentration has been shown to be inversely associated with cardiovascular disease (CVD) and CVD risk. Based on this observation, increasing the plasma HDL-C concentration is thought to be a desirable strategy, in the 21st century, for decreasing the burden of CVD.

Recent studies have shown that powerful HDL-C concentration-increasing drugs are ineffective for decreasing CVD. Increasing evidence now shows that HDL is an unstable and heterogeneous particle, and that 'HDL particle functionality' is far more important in atheroprotection than is the HDL-C level, alone. Apolipoprotein A-I (apoA-I) is the major protein component of HDL, and increasing evidence suggests that the ratio of HDL-C to apoA-I may give additional insight as a risk marker not just for CVD but also for all-cause and cancer mortality.

In this review, we discuss the importance of HDL composition, apoA-I levels, and the HDL-C/apoA-I ratio for predicting CVD and mortality outcomes.