To investigate the risk factors for patients with acute pancreatitis (AP) combined with portal vein system thrombosis (PVST) and develop a predictive model.

A retrospective analysis was conducted in clinical data of patients undergoing treatment for pancreatitis at the First Affiliated Hospital of Xinjiang Medical University from January 2020 to December 2022. 188 cases of AP were finally included based on the inclusion and exclusion criteria, with 46 cases in the thrombosis group and 142 cases in the non-thrombosis group. Clinical data of the two groups were compared to analyze the risk factors for PVST in patients with AP and develop a predictive model. Receiver operating characteristic curve (ROC), calibration curve, Hosmer-Lemeshow test, and clinical decision curve were used for evaluation.

PVST occurred in 46 (24.47%) of the 188 patients with AP. Multivariate Logistic regression analysis showed that ascites (OR=2.28, 95% CI: 1.04-5.00, P=0.040), white blood cell count ≥10×10⁹/L (OR=3.69, 95% CI: 1.55-8.78, P=0.003), and TYG ≥9.21 (OR=4.38, 95% CI: 1.90-10.11, P=0.001) were independent risk factors for PVST in patients with AP. ROC curve analysis of these risk factors yielded an area under the curve of 0.790. The Hosmer-Lemeshow test showed χ² value of 4.293 and P value of 0.891, indicating that there was no statistically significant lack of fit between the predicted values and observed values. The Brier score of the calibration curve was 0.144, indicating high accuracy of the model in prediction with small differences between the predicted and observed values. The created predictive model for PVST in patients with AP allowed for initial risk assessment based on the calculated scores.

Ascites, white blood cell count≥10×10⁹/L, and TYG≥9.21 are independent risk factors for the development of PVST in patients with AP. The constructed column chart based on these risk factors demonstrates good discriminatory power and accuracy, providing references for the treatment strategies for PVST with AP.