Remnant cholesterol and cardiovascular and all-cause mortality in Korean adults

Previous studies have investigated the relationship between remnant cholesterol (RC) and mortality outcomes in the general population, but the majority have focused on Western populations.

This study aims to evaluate the association between RC and mortality-related outcomes in a relatively young and middle-aged Korean population.

This cohort study included 268,219 participants (mean age, 38 years; 50.6% men) who were enrolled in the Kangbuk Samsung Health Study between 2003 and 2016. Fasting RC was calculated as total cholesterol minus low-density lipoprotein cholesterol minus high-density lipoprotein cholesterol.

The median RC was 0.47 mmol/L (18 mg/dL) and the prevalence of ≥1 mmol/L RC was 11.4%. During the median follow-up of 6.7 years, compared with the lowest quintile (RC <0.31 mmol/L), the hazard ratios (HRs) and 95% CIs for cardiovascular mortality were 1.95 [0.78, 4.84], 2.47 [1.03, 5.91], 2.39 [1.00, 5.72], and 2.84 [1.19, 6.78] in the second, third, fourth, and highest quintiles, respectively. The HRs for all-cause mortality in the third, fourth, and highest quintiles remained significant but were not significant for the risk of cancer mortality. Subgroup analyses showed that the high RC group with high-sensitivity C-reactive protein (hsCRP) or high lipoprotein(a) levels had more than 2-fold and 3-fold increased risks of cardiovascular mortality than the low RC group with low hsCRP or low lipoprotein(a) levels.

High RC levels were significantly associated with an increased risk of cardiovascular and all-cause mortality, but not with cancer mortality. Specifically, high hsCRP and lipoprotein(a) levels weighted the risk association between high RC and cardiovascular mortality.