Remnant Cholesterol and Prognostic Outcomes in Patients With Atrial Fibrillation on Oral Anticoagulants

Background The relationship between dyslipidemia, a significant contributor to atherosclerotic cardiovascular disease, and atrial fibrillation remains unclear. This study aims to investigate the impact of remnant cholesterol (RC) on the prognosis of patients with atrial fibrillation on oral anticoagulants. Methods A total of 23 267 patients with atrial fibrillation on oral anticoagulants from the Tianjin Health Medical Data Platform in China were identified for the analysis. We categorized participants into RC tertiles and used a multivariate Cox model to evaluate outcomes. Subgroup and sensitivity analyses were used to evaluate the association between RC tertiles and all‐cause death. The study analyzed the combined effect of RC and low‐density lipoprotein cholesterol on outcomes on the basis of the median levels of both lipids. Results The top RC tertile (tertile 3) was associated with a 24% increased risk of all‐cause death (hazard ratio HR, 1.24 95% CI, 1.11–1.38), 18% increased risk of ischemic stroke (HR, 1.18 95% CI, 1.00–1.38), and 35% increased risk of acute myocardial infarction (HR, 1.35 95% CI, 1.07–1.71) compared with the bottom RC tertile (tertile 1). A sex‐specific interaction was noted for RC and death, with the association appearing more evidently in men. The results remained consistent throughout various sensitivity analyses. This association with RC appeared to persist even when low‐density lipoprotein cholesterol levels were relatively low (below the median of 102 mg/dL), showing a 17% increased risk of composite ischemic outcomes (HR, 1.17 95% CI, 1.01–1.37). Conclusions Higher RC levels in patients with atrial fibrillation receiving oral anticoagulation therapy were associated with an increased risk of death, acute myocardial infarction, and ischemic stroke.