Prognostic analysis of acute pancreatitis due to different etiologies and establishment and validation of an early prediction model

Acute pancreatitis (AP), an acute inflammatory condition commonly encountered in patients admitted to intensive care unit, is mainly caused by gallstones, alcohol abuse, or hyperlipidemia. Traditional views focus on single-etiology AP; however, Chinese studies have shown that mixed-etiology AP (two or more etiologies) is also fairly common. Comparing the clinical characteristics of AP with different etiologies is crucial for guiding personalized treatment strategies and understanding disease severity and recurrence patterns. However, few studies have explored the prognostic differences between single-etiology and mixed-etiology AP; moreover, the predictors of disease severity in mixed-etiology AP cases remain unclear. This retrospective cohort study compared severity and prognostic outcomes between single-etiology AP and mixed-etiology AP and established a predictive model for severe AP (SAP) in mixed-etiology AP patients. For this purpose, patients diagnosed with AP from January 2019 to December 2023 at the First Affiliated Hospital of Xi’an Jiaotong University were recruited. Of 630 AP patients, 18.3% (n = 115) had mixed-etiology AP. Compared to single-etiology AP, mixed-etiology AP exhibited significant associations with higher incidences of SAP, organ failure, and local/systemic complications (all P < 0.05). Among mixed-etiology subgroups, cholelithiasis combined with hypertriglyceridemia showed an association with the highest persistent organ failure rate (50.0%), while cholelithiasis combined with alcohol was linked with more local complications and higher hospitalization costs. By employing least absolute shrinkage and selection operator regression and multivariate logistic regression analyses, this study constructed a SAP prediction model for mixed-etiology AP based on albumin (odds ratio [OR]: 0.87, 95% confidence interval [CI]: 0.79–0.95), serum calcium (OR: 0.08, 95% CI: 0.01–0.45), and D-dimer (OR: 1.13, 95% CI: 1.02–1.26). The model showed an area under the curve (AUC) value of 0.857, thus outperforming APACHE II, SOFA, and BISAP scores (AUC = 0.745, 0.764, and 0.748, respectively); additionally, it exhibited good consistency and positive net clinical benefits, as validated by calibration procedures and decision curve analyses. Mixed-etiology AP might pose a high risk of adverse clinical outcomes in AP patients. The three-marker prediction model (albumin, serum calcium, and D-dimer) established in the current single-center retrospective study shows high accuracy and potential clinical utility for predicting SAP in mixed-etiology AP, which may enable to early recognize high-risk patients. However, because of limitations related to study design, further prospective multicenter studies are required for validating the generalizability and clinical utility of the model and optimizing treatment strategies.