Background: Thionamides have been extensively used to treat patients with hyperthyroidism worldwide. Recent pharmacovigilance studies have revealed a safety signal between carbimazole or methimazole and pancreatitis. The associated risk remains unclear. Methods: We identified patients with newly diagnosed acute pancreatitis from 2000 to 2013 as the case group from the Taiwan Longitudinal Health Insurance Database 2000, which contains data from 1996 to 2013. Each patient with acute pancreatitis was matched for age, sex, comorbidities, and cancer with four controls through propensity score matching. A total of 52 patients without matched controls were excluded. Sensitivity analyses including the 52 excluded patients were performed using a matching ratio of 1:2. Odds ratios (ORs) along with 95% confidence intervals (CIs) for the association were estimated using multivariate logistic regression. Results: We included 9204 and 36,816 patients in the case and control groups, respectively. The proportions of patients who had used thionamides, carbimazole, methimazole, and propylthiouracil were similar in these two groups. In addition, the adjusted OR (CI) for the association of acute pancreatitis with thionamides was 1.03 (0.86-1.24), with carbimazole it was 0.90 (0.63-1.30), with methimazole it was 1.05 (0.84-1.31), and with propylthiouracil it was 1.00 (0.74-1.34). The sensitivity analysis results were unchanged. Conclusions: We were unable to demonstrate an association between acute pancreatitis and usage of thionamides.
Keywords: carbimazole; hyperthyroidism; methimazole; pancreatitis; propylthiouracil; thionamides.