Very High High-Density Lipoprotein Cholesterol Levels and Cardiovascular Mortality

Previous studies have shown reduced cardiovascular risk with increasing high-density lipoprotein cholesterol (HDL-C) levels. However, recent data in the general population have shown increased risk of adverse outcomes at very high concentrations of HDL-C. Thus, we aimed to study the gender-specific relation between very high HDL-C levels (>80, >100 mg/100 ml) and adverse cardiovascular outcomes and the genetic basis in the general population enrolled in the United Kingdom Biobank. A total of 415,416 participants enrolled in the United Kingdom Biobank without coronary artery disease were included in this prospective cohort study, with a median follow-up of 9 years. A high HDL-C level >80 mg/100 ml was associated with increased risk of all-cause death (Hazard ratio [HR] 1.11, confidence interval [CI] 1.03 to 1.20, p = 0.005) and cardiovascular death (HR 1.24, CI 1.05 to 1.46, p = 0.01) after adjustment for age, gender, race, body mass index, hypertension, smoking, triglycerides, LDL-C, stroke history, heart attack history, diabetes, eGFR, and frequent alcohol use (defined as ≥3 times/week) using Cox proportional hazard and Fine and Gray's subdistribution hazard models, respectively. In gender-stratified analyses, such associations were only observed in men (all-cause death HR 1.79, CI 1.59 to 2.02, p <0.0001; cardiovascular death HR 1.92, CI 1.52 to 2.42, p <0.0001), but not in women (all-cause death HR 0.97, CI 0.88 to 1.06, p = 0.50; cardiovascular death HR 1.04, CI 0.83 to 1.31, p = 0.70). The findings persisted after adjusting for the genetic risk score comprised of known HDL-C-associated single nucleotide polymorphisms. Very high HDL-C levels are associated with an increased risk of all-cause death and cardiovascular death among men but not in women in the general population free of coronary artery disease.