Remnant Cholesterol as an Independent Cardiovascular Risk Factor in Young Adults: An Age-Stratified Cohort Study

Remnant cholesterol (remnant-C) has emerged as an important contributor to the residual risk of cardiovascular disease beyond low-density lipoprotein cholesterol (LDL-C). However, evidence on its age-specific association, especially in young adults, remains limited.

This study aimed to investigate the association between remnant-C and major adverse cardiovascular events (MACE) across different age groups.

This study included 4,308,405 participants without a history of myocardial infarction (MI) or ischemic stroke who underwent national health examinations in 2012 and were followed up for MACE for a median of 9.3 years. Multivariate Cox proportional hazards models were used to assess the association between remnant-C quartiles and MACE in the overall population and within each age group (20-39, 40-64, and ≥65 years). Remnant-C was calculated as non-high-density lipoprotein cholesterol minus LDL-C in the fasting state.

During the follow-up, 78,223 MIs, 84,832 ischemic strokes, and 26,774 cardiovascular deaths were documented. Higher remnant-C quartiles were independently associated with a greater risk of MACE across all age groups, with the strongest association observed in younger individuals. Among participants 20 to 39 years of age, adjusted HRs comparing the highest to the lowest remnant-C quartile were 1.42 (95% CI: 1.32-1.52) for MI, 1.30 (95% CI: 1.19-1.42) for ischemic stroke, and 2.19 (95% CI: 1.79-2.68) for cardiovascular mortality, compared with 1.07 (95% CI: 1.03-1.12), 1.12 (95% CI: 1.08-1.16), and 1.08 (95% CI: 1.02-1.13), respectively, among those ≥65 years of age. In those 20 to 39 years of age with optimal LDL-C level (<100 mg/dL) but high remnant-C level (≥30 mg/dL), the adjusted HRs were 1.24 (95% CI: 1.10-1.41) for MI, 1.29 (95% CI: 1.10-1.52) for ischemic stroke, and 1.83 (95% CI: 1.35-2.49) for cardiovascular mortality.

Elevated remnant-C levels confer an independent risk of MACE, most notably in young adults. The identification of high remnant-C levels at a young age may enhance preventive strategies.