A Swedish case-control network for studies of drug-induced morbidity – acute pancreatitis

Abstract Objective. To evaluate risk factors – notably drugs – for developing acute pancreatitis. Methods. A population-based, case-control study, encompassing 1.4 million inhabitants aged 20–85 years from four regions in Sweden between 1 January 1995 and 31 May 1998. A total of 462 cases were hospitalised in surgical departments with their first episode of acute pancreatitis without previously known biliary stone disease. From a population register, 1781 controls were randomly selected. Information was obtained from medical records and through telephone interviews. Results. Fifty-seven percent of the cases were males. An expert group found evidence for biliary stones in 50% of the cases, alcohol intake in 23%, but in 29% neither of these factors were present. In all, "other" factors, e.g. drugs, could have contributed to the development of acute pancreatitis in 52% of the cases. In a multivariate analysis, the adjusted odds ratios (ORs) for H2 antagonists were 2.4 (95% CI 1.2–4.8) for proton pump inhibitors (PPIs), 2.1 (1.2–3.4) for non-steroidal anti-inflammatory drugs (NSAIDs), 2.3 (1.3–4.0) for those derived from acetic acid and 1.9 (1.1–3.2) for antibacterials for systemic use. Significant ORs were found for a history of gastrointestinal tract disorders [1.5 (1.1–1.9)] and inflammatory bowel disease (IBD) [3.4 (1.5–7.9)]. Smoking was significantly associated with acute pancreatitis [1.7 (1.2–2.1)] and, for those smoking more than 20 cigarettes per day, the OR was 4.0 (2.2–7.5). Alcohol in moderate amounts did not increase the risk, but for those drinking more than 420 g alcohol per week the OR was 4.1 (2.2–7.5). Conclusion. In addition to cholelithiasis, smoking and heavy alcohol use, drugs may be an important risk factor for acute pancreatitis.