Progression to recurrent acute pancreatitis after a first attack of acute pancreatitis in adults

Patients with a first attack of acute pancreatitis (AP) can develop recurrent acute pancreatitis (RAP). Hence, this study aimed to investigate the clinical features of the disease and the risk factors for RAP. We performed a retrospective study of 522 patients from Jan 1 to Dec 31, 2006. All patients with AP were followed for 36 months. The primary end point was the rate of RAP. The secondary end points were the risk factors that were evaluated by Cox regression analysis. The cumulative risk of RAP was assessed using Kaplan-Meier analysis. 56 of the 522 patients (10.7%) developed RAP. Among those RAP patients, 37 (7.1%) experienced one relapse, 10 (1.9%) experienced two relapses, and 9 (1.7%) experienced three or more relapses. Univariate analysis indicated that age (p = 0.016), male sex, etiology of AP (p = 0.001), local complications (p = 0.001) and Length of stay (LOS) (p = 0.007) were associated with RAP. Multivariate analysis with the Cox proportional hazards model showed that male sex (HR = 2.486, 95% CI, 0.169–0.960, p = 0.04), HTG-associated etiology (HR = 5.690, 95% CI, 2.138–15.146, p = 0.001), alcohol-associated etiology (HR = 5.867, 95% CI, 1.446–23.803, p = 0.013) and current local complications at index admission (HR = 8.917, 95% CI, 3.650–21.789, p = 0.001) were significant independent risk factors for RAP. A first attack of AP led to RAP in 10.7% of patients within 3 years. Male sex was significantly associated with RAP. The etiologies of alcohol and HTG and local complications were the strongest risk factors for recurrent disease. Patients with these characteristics should be given special attention and followed-up closely.