BACKGROUND /objectives: Acute pancreatitis (AP) is an acute inflammatory disorder that can occur in all age groups. The risk of AP has been shown to increase with age. However, no study has compared risk factors for AP according to age group yet. Thus, the aim of this study was to perform such comparison.

METHODS Clinical data from individuals 20 years of age and older who received a health examination arranged by the Korean national health insurance program in 2009 (n = 4,238,822) were used. First-attack AP was identified using claims data from baseline to December 2018. Incidence and risk factors of AP were analyzed for young (20-39 years old), middle-aged (40-64 years old), and old (over 65 years old) groups.

RESULTS Incidences of AP in young, middle-aged, and old groups were 16.30, 27.85, and 57.19 per 100,000 person-years, respectively. Smoking, alcohol drinking, diabetes, gallstone, and chronic pancreatitis were associated with increased risk of AP in all age groups. Meanwhile, male, older age, and higher waist circumference were associated with increased risk of AP in middle-aged and old groups. In young and middle-aged groups, risk of AP was increased in the presence of hypertension and dyslipidemia. However, high income was associated with decreased risk of AP in these groups.

CONCLUSIONS In this population-based cohort study, incidences and risk factors for AP differed according to age group. Thus, a tailored strategy might be needed to prevent AP according to age group.