Associations between remnant cholesterol and cardiovascular events in patients undergoing dialysis: a nationwide cohort study

Background: Remnant cholesterol is a known residual risk factor for cardiovascular disease in the general population. However, its prognostic value in patients undergoing dialysis, a population at a high risk of cardiovascular events, remains unclear. We aimed to evaluate the association between remnant cholesterol levels and cardiovascular outcomes in a high-risk population. Methods: This retrospective cohort study included 21,679 patients with end-stage kidney disease on long-term dialysis, who underwent health screening between 2009 and 2017. All participants were identified from the Korean National Health Insurance Service database. The participants were stratified into quartiles of baseline remnant cholesterol. The primary outcomes were the incidences of myocardial infarction and ischemic stroke. Results: During a median follow-up of 8.1 years, 993 myocardial infarctions and 1,249 ischemic strokes occurred. High remnant cholesterol was associated with an increased risk of myocardial infarction; patients in Quartile 4 had a 26% higher risk compared with Quartile 1 (hazard ratio, 1.26; 95% confidence interval, 1.04-1.53), in the fully adjusted model including low-density lipoprotein cholesterol (LDL-C). Restricted cubic spline analyses showed a steady increase in myocardial infarction risk with rising remnant cholesterol. However, no significant association was observed with ischemic stroke. Conclusion: In patients undergoing dialysis, elevated remnant cholesterol was independently associated with a higher risk of myocardial infarction but not ischemic stroke. These findings suggest that remnant cholesterol is associated with myocardial infarction independent of LDL-C and may contribute to residual cardiovascular risk in this population.