Sex Differences in Lipids and Lipoproteins and Their Relationship With Cardiovascular Disease: A Prospective Study of UK Biobank Participants

BACKGROUND: Sex-specific differences in serum lipids are recognized, but their relationship with cardiovascular disease (CVD) has not been reliably quantified. We examined sex-specific associations of major lipids and apolipoproteins with incident CVD. METHODS: We included 432 092 UK Biobank participants without CVD at baseline (2006-2010) and with ≥1 lipid measurement. Age-adjusted risks were estimated using Poisson regression. Multivariable Cox models estimated hazard ratios (HRs) and women-to-men ratios of HRs for 1-SD higher values of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apoB (apolipoprotein B), apoA1 (apolipoprotein A1), and Lp(a) (lipoprotein [a]). RESULTS: Over a mean 13.3 years of follow-up, there were 10 699 and 18 950 cases of CVD in women and men, respectively. CVD risk per 10 000 person-years was 33.4 (95% CI, 32.7-34.0) for women and 76.6 (95% CI, 75.5-77.7) for men. Low-density lipoprotein cholesterol, apoB, and log Lp(a) were associated with smaller HRs of CVD for women than men (ratio of HR, 0.94 [95% CI, 0.91-0.97], ratio of HR, 0.94 [95% CI, 0.92-0.97] and ratio of HR, 0.96 [95% CI, 0.93-0.99], respectively). Triglycerides were associated with larger HRs of CVD in women than men (ratio of HR, 1.06 [95% CI, 1.02-1.09]). The association of lower apoA1 with higher CVD risk was stronger in men than women (ratio of HR, 1.06 [95% CI, 1.03-1.10]). No sex difference was observed for high-density lipoprotein cholesterol (ratio of HR, 1.02 [95% CI, 0.98-1.06]). CONCLUSIONS: Men had a higher rate of CVD than women overall. Low-density lipoprotein cholesterol, apoB and Lp(a) had stronger associations with CVD risk in men, whereas triglycerides were stronger in women. ApoA1 was less protective for CVD in women than men.