Association of HDL cholesterol with all-cause and cardiovascular mortality in primary hypercholesterolemia

Background and aims: Recent reports have shown that subjects with high high-density lipoprotein cholesterol (HDLc) levels are paradoxically at increased risk for all-cause and cardiovascular mortality. The aim was to study the association of HDLc concentration with mortality in subjects with high cholesterol. Methods: We analyzed total mortality, cardiovascular mortality, and non-cardiovascular mortality in a cohort of 2992 subjects with primary hypercholesterolemia, who were followed for 10.2 years (range 1-25 years), with a total of 30,602 subject-years of follow-up. Results: During follow-up, 168 subjects died, with 52 (13.7 %), 105 (4.80 %), and 11 (2.60 %) in the low, normal, and high HDLc groups, respectively (p < 0.001). The risk of death was 2.89 times higher (95 % confidence interval (CI), 1.50-5.57, p < 0.001) in subjects in the low HDLc group compared to those in the high HDLc group and 1.48 times higher (95 % CI 0.80-2.76, p = 0.214) in the normal HDLc group compared to the high HDLc group. However, HDLc concentration and HDLc groups based on HDLc concentration were not independently associated with mortality in Cox regression analysis. Cardiovascular and non-cardiovascular mortalities showed similar results. Conclusions: All types of mortality were lower in subjects with primary hypercholesterolemia and with high HDLc in univariate analysis. Elevated HDLc was not associated with total, cardiovascular, and non-cardiovascular mortality when adjusted for major cardiovascular risk factors.