Dipeptidyl Peptidase-4 Inhibitors and Bullous Pemphigoid: A Danish Nationwide Case-Control Study.
Ahle Erichsen Philip P, Heerfordt Ida M IM, Huan Olsen Rasmus R, Mogensen Mette M et al.
Anti-diabetic dipeptidyl peptidase-4 inhibitors (DPP-4i) are associated with an increased risk of bullous pemphigoid (BP), but Danish population-based data, including product specific estimates, are lacking. We conducted a nationwide matched case-control study in Denmark of incident BP cases diagnosed between 2007 and 2024. BP cases were matched 1:100 to population controls using risk set sampling based on age, sex, and index date. DPP-4i exposure was defined as at least one redeemed prescription before the index date (ever use) or during the preceding three months (current use). In a specificity analysis, we compared DPP-4i users and users of other type 2 antidiabetics without DPP-4i use with non-users of type 2 diabetes medications. Odds ratios (ORs) with 95% CIs were estimated using conditional logistic regression. We identified 2,497 incident BP cases and 249,700 controls (median age 78 years). DPP-4i exposure was more common among BP cases for both ever use (OR: 3.81, 95% CI: 3.31-4.40) and current use (OR: 5.59, 95% CI: 4.70-6.63). For current use, the highest odds ratios were observed for vildagliptin (OR: 10.82, 95% CI: 6.73-17.41) and linagliptin (OR: 9.86, 95% CI: 7.33-13.25), whereas the estimate for sitagliptin was lower (OR: 2.46, 95% CI: 1.65-3.66). In the specificity analysis, other antidiabetic therapies did not show a similarly increased risk of BP. In the Danish population there was a strong association between DPP-4i use and incident BP. This was most pronounced for vildagliptin and linagliptin while the signal was weaker for sitagliptin.