Estimated Glucose Disposal Rate Predicts Cardiovascular Disease Risk Among Adults with Short Sleep Duration: A National Prospective Cohort Study

Background Short sleep duration is associated with insulin resistance (IR), potentially elevating cardiovascular disease (CVD) risk. The estimated glucose disposal rate (eGDR), a practical surrogate marker of insulin sensitivity, remains understudied in relation to cardiovascular outcomes among adults sleeping ≤ 6 hours per night. To investigate whether higher eGDR is independently associated with lower incidence of CVD and stroke among Chinese adults reporting short sleep duration. Methods This prospective cohort study analyzed data from 4,717 participants aged ≥ 45 from the China Health and Retirement Longitudinal Study (CHARLS, baseline 2011). Inclusion required self-reported sleep ≤ 6 hours, no baseline CVD and complete data to compute eGDR (formula: 21.158-(0.09×WC)-(3.407×hypertension)-(0.551×HbA1c)). Participants were categorized into eGDR quartiles (Q1–Q4). Cox proportional hazards models and restricted cubic spline (RCS) analyses examined associations and dose-response relationships. Results Participants (mean age 60.34 ± 9.25 years; 55.12% female) were followed for a median of 84 months. Lower eGDR levels correlated significantly with increased risk of CVD. Compared to the lowest quartile (Q1), hazard ratios (HRs) for CVD were: Q2: 0.82 (95% CI: 0.72–0.95), Q3: 0.71 (0.61–0.82), Q4: 0.63 (0.54–0.75). Each SD increase in eGDR was associated with 17% reduced CVD risk (HR: 0.83; 95% CI: 0.78–0.83). Subgroup analysis identified significant interactions with gender and obesity for stroke outcomes. Obesity mediated 18.5–20% of the eGDR-CVD relationship. Adding eGDR significantly enhanced predictive accuracy of conventional risk models (C-statistic increased from 0.627 to 0.663, P = 0.016). Conclusions Higher eGDR is independently protective against CVD and stroke among short-sleeping adults. Integrating eGDR into clinical assessments could effectively identify high-risk individuals for targeted cardiometabolic prevention strategies.