Admission HDL-C and recurrence risk of hypertriglyceridemia-induced acute pancreatitis: a multicenter cohort study

Background Hypertriglyceridemia-induced acute pancreatitis (HTG-AP) carries a high risk of post-discharge recurrence. Whether admission high-density lipoprotein cholesterol (HDL-C) independently predicts recurrence and how its effect varies over time remain unclear. Methods A multicenter retrospective study was conducted, including consecutive HTG-AP inpatients from three hospitals from January 2020 to March 2025. The primary endpoint was overall post-discharge recurrence; while the secondary endpoints included recurrence within 6 and 12 months. HDL-C, analyzed both as a continuous variable and by tertiles, was evaluated using Cox models with progressive adjustment. Dose–response was examined by restricted cubic splines (RCS). Time-varying effects were assessed with landmark analyses (0–6 and 6–12 months) and an HDL × log(time) interaction. Robustness was tested using inverse probability of treatment weighting (IPTW). Restricted mean time free of recurrence (RMST) quantified absolute differences. Results A total of 440 patients were enrolled, and the median follow-up duration was 14.0 months. Lower admission HDL-C was associated with a higher recurrence risk. In the fully adjusted model, each 1 mmol/L increase in HDL-C was associated with a 77% lower hazard of overall recurrence (HR 0.23, 95% CI 0.11–0.48; p < 0.001). Compared with the lowest tertile (T1), risks were reduced in T2 (HR 0.42, 95% CI 0.27–0.64) and T3 (HR 0.33, 95% CI 0.19–0.55; p for trend