Association of remnant cholesterol with stroke risk by glycemic status: a nationwide prospective cohort study

The role of elevated remnant cholesterol (RC) across different glycemic status categories remains unclear.

We used data from the China Health and Retirement Longitudinal Study (CHARLS), including 9,182 participants aged ≥ 45 years without prior stroke. Baseline RC was categorized into quartiles. Incident self-reported stroke over 7 years was the primary outcome. Associations between RC and stroke were assessed using Kaplan-Meier curves, Cox proportional hazards models, and restricted cubic spline (RCS) analyses, with stratification by glucose metabolism status and by the clinical low-density lipoprotein cholesterol (LDL-C) threshold of 130 mg/dL.

During follow-up, 867 participants (9.44%) developed stroke. Stroke risk increased across RC quartiles in the overall cohort and among those with prediabetes (Pre-DM) and diabetes mellitus (DM), but not in individuals with normal glucose regulation (NGR). In fully adjusted models for the overall cohort, compared with the lowest RC quartile, hazard ratios (95% CIs) were 1.228 (0.980-1.537), 1.390 (1.116-1.730), and 1.419 (1.138-1.769) for quartiles 2-4, respectively. In analyses stratified by LDL-C, associations were stronger when LDL-C was <130 mg/dL, and were significant in Pre-DM and DM but not in NGR.

In individuals with Pre-DM and DM, higher RC independently predicts incident stroke, especially when LDL-C is <130 mg/dL, supporting RC as a potential target after LDL-C goals are achieved.