Dipeptidyl-peptidase IV inhibitor (DPP4i) confers increased odds of bullous pemphigoid even years after drug initiation

The timing pattern in which dipeptidyl-peptidase IV inhibitors (DPP4i) confer the risk of bullous pemphigoid (BP) is unknown. To investigate the odds of BP following exposure to DPP4i and to perform a duration-response analysis evaluating the risk of BP in relation to the duration of exposure to the culprit drug. A population-based nested case–control study was performed comparing diabetic patients with BP ( n = 1458) with age-, sex- and ethnicity-matched diabetic control subjects ( n = 6051) with respect to the prevalence of exposure to DPP4i. Adjusted odds ratios (ORs) were estimated by logistic regression. Overall exposure to DPP4i was associated with an 80% increase in the odds of subsequent BP (OR, 1.81; 95% CI, 1.46–2.08; P