Remnant cholesterol and risk of myocardial infarction in patients with coronary artery disease undergoing revascularization

Abstract

Despite substantial reduction in low-density lipoprotein cholesterol (LDL-C), patients develop recurrent cardiovascular events. Remnant cholesterol (RC), the cholesterol content of triglyceride-rich lipoproteins, is a potential contributor to this residual risk. To investigate the association between RC and risk for myocardial infarction (MI) in patients with coronary artery disease, and examine whether the predictive value of RC is retained beyond non-high-density lipoprotein cholesterol (non-HDL-C). Data on 9451 patients undergoing coronary revascularization in a single center. RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus LDL-C (estimated using Martin-Hopkins equation). Cox-regression models were used to estimate the association between RC and risk for MI. Discordance analyses were performed to examine the correlation between RC and non-HDL-C (or LDL-C) in relation to MI risk. Mean age was 65±11 years; 67% presented with acute coronary syndrome. During median follow-up of 9.6 years, 1690 patients developed MI. After multivariable adjustment including lipid-lowering therapies and non-HDL-C, RC was associated with higher MI risk: hazard ratio (95% confidence interval): 1.36 (1.20-1.56) and 1.58 (1.35-1.85) in those with RC levels ≥75th (32.6mg/dL) and ≥90th (41.8mg/dL) percentile, compared to RC <50th percentile (25.5mg/dL). When RC and non-HDL-C (or LDL-C) levels were discordant, the level of RC better reflected the risk for MI. Elevated RC is a risk factor for MI independent of lipid-lowering therapies and non-HDL-C, providing further support that RC may serve as a residual cardiovascular risk marker and potential treatment target in patients with coronary artery disease.