Emerging importance of remnant cholesterol compared with low-density lipoprotein cholesterol in cardiovascular risk assessment

Remnant cholesterol (RC) has been identified as a risk factor for cardiovascular disease (CVD) for many years. However, its importance was largely overlooked until recently, when it began to receive increased attention, even more so than traditional lipid components. This study examined the relationship between concordant and discordant levels of RC and low-density lipoprotein cholesterol (LDL-C) and incidence of CVD, coronary artery disease (CAD), ischemic stroke, and CVD mortality. This study is part of a 10-year cohort study in northeastern Iran that measured LDL-C and RC at baseline. Outcomes included CVD, CAD, stroke, and mortality. Participants were categorized by RC (< 24 mg/dL or ≥ 24 mg/dL) and LDL levels (< 130 or ≥ 130 mg/dL). A total of 9704 individuals participated in the study. Cox regression analysis revealed that individuals with RC ≥ 24 showed a 1.35- (LDL < 130) and 1.58-fold (LDL ≥ 130) increased risk of CVD (95%Cl: 1.124-1.638 and 1.293-1.95) and a 1.45- (LDL < 130) and 1.63-fold (LDL ≥ 130) increased risk of CAD (95%Cl: 1.186-1.772 and 1.311-2.034), compared to the RC < 24, LDL < 130 group. Additionally, those with RC < 24 and LDL ≥ 130 had a 1.29-fold risk of CVD (95%Cl: 1.020-1.65) and a 1.38-fold risk of CAD (95%Cl: 1.077-1.789). Elevated levels of LDL-C and RC are strong predictors of CVD and CAD. Notably, high RC with low LDL-C offers better risk prediction than high LDL-C with low RC, emphasizing the role of RC in cardiovascular risk assessment. However, no link was found between lipid levels and ischemic stroke or CVD mortality, indicating a need for further research in these areas.