Abstract 1462: Association of HDL Cholesterol and Apolipoprotein A-1 With Incident CVD Across Levels of LDL Cholesterol in 27,748 Women

Abstract

Background Prior studies have found an inverse association between HDL cholesterol (HDL-C) and apolipoprotein A-1 (apoA-1) with CVD events. Whether this association is consistent in subjects with different levels of LDL cholesterol (LDL-C) is less well studied, particularly in women.

Methods We tested the hypothesis that low HDL-C and apoA-1 are risk factors for CVD across a range of LDL-C levels. Baseline lipids were measured directly, and apoA-1 with an immunoassay, in 27,748 apparently healthy women (mean age 54.7 years) with 11-year follow-up for first CVD events (N=1,017) in the Women’s Health Study.

Results There was a strong inverse association between HDL-C, apoA-1, and risk of CVD. The fully-adjusted hazard ratios (HRs) associated with decreasing quintiles of HDL-C were 1.00, 1.18 (0.90 –1.53), 1.32 (1.01–1.72), 1.50 (1.15–1.96), and 1.66 (1.26 –2.19), P_trend<0.001. Similarly-adjusted HRs for apoA-1 quintiles HRs were 1.00, 1.11 (0.88 –1.41), 1.08 (0.83–1.39), 1.51 (1.18 –1.92), and 1.42 (1.10 –1.83), P_trend=0.001. The association of HDL-C with CVD was consistent across levels of LDL-C (Figure⇓), and similarly for apoA-1. Women with HDL-C >90^th percentile (>69 mg/dL) had onset of CVD 10 years later than women with HDL-C <10^th percentile (<35 mg/dL, P<0.001).

Conclusion In this study of apparently healthy women, HDL-C and apoA-1 were inversely associated with CVD across levels of LDL-C. For women with very high levels of HDL-C, the onset of their first event was delayed by up to 10 years compared with women with low levels of HDL-C.

This research has received full or partial funding support from the American Heart Association, National Center.

Figure.

CVD incidence rate according to HDL cholesterol and LDL cholesterol clinical cutpoints.