Association Between High-Density Lipoprotein Cholesterol and Length of Hospital Stay in Acute Pancreatitis: A Retrospective Cohort Study.

Background: Acute pancreatitis (AP) is a complex inflammatory disorder with varying degrees of severity, impacting patient recovery and healthcare resource utilization. The length of hospital stay (LOS) is a pivotal indicator of recovery, and identifying factors influencing LOS can offer insights into AP management. High-density lipoprotein cholesterol (HDL-C), known for its cardioprotective properties, has been posited to influence AP outcomes; however, its relationship with LOS remains unclear. Objective: This study aimed to investigate the potential correlation between HDL-C levels and LOS in patients with AP, considering the effects of demographic factors, comorbidities, and other clinical parameters. Methods: A retrospective cohort study was conducted. Data collection adhered to the STROBE guidelines, and baseline clinical and laboratory variables were analyzed. Statistical analysis comprised univariate and multivariate regression models, Generalized Additive Models (GAM), and stratified linear regression models to assess the relationship between HDL-C and LOS, while accounting for confounding factors. Results: After adjusting for key confounders, including age, sex, BMI, WBC, HB, PLT, CRP, ALT, AMY, TB, GLU, LDL-C, SCR, BUN, ALB, Ca2+, and the presence of comorbidities such as hypertension, gallstones, diabetes mellitus, liver dysfunction, renal insufficiency, smoking and alcohol consumption, the study revealed a nonlinear relationship between HDL-C levels and LOS, with an inflection point at 1.5 mmol/L. Below this threshold, HDL-C was significantly and inversely correlated with LOS, whereas above this threshold, HDL-C was positively correlated with LOS. Subgroup analyses emphasized that in non-diabetic, non-alcoholic and non-hyperlipidemic pancreatitis patients, there is a negative correlation between HDL-C levels and LOS. Conclusion: HDL-C exhibits a U-shaped relationship with LOS in patients with AP, suggesting that both low and high levels of HDL-C may influence hospital stay duration. These findings underscore the importance of considering HDL-C levels in the clinical management of AP. Especially in patients who are non-diabetic, non-hyperlipidemic, and non-alcoholic, the management of HDL-C may significantly reduce hospital stay.