Prevalence of diabetes mellitus in bullous pemphigoid patients in the absence of dipeptidyl peptidase-4 inhibitors: a systematic review and meta-analysis

Bullous pemphigoid (BP) has been associated with dipeptidyl peptidase-4 inhibitor (DDP-4i) use in patients with diabetes mellitus (DM). The prevalence and association of DM in BP patients independent of DPP-4i use has not been investigated by meta-analysis. To perform a systematic review and meta-analysis on the association between diabetes and bullous pemphigoid. The goal was to determine the prevalence and pooled odds ratio of BP patients with DM in the absence of DDP-4i use compared to the general population prevalence of diabetes mellitus. OVID Medline, EMBASE, Cochrane Central and Web of Science were searched for relevant studies published from inception to April 2020. Case–control, case-series, cohort, and cross-sectional studies that included the association of BP and DM without DDP-4i’s, in any language. PRISMA guidelines were followed for data extraction and the Newcastle–Ottawa Scale for risk of bias evaluation. Three reviewers independently performed data extraction. Pooled odds ratio and prevalence were calculated using the random effects model. The odds ratio and prevalence of BP patients with DM. Overall, 8 studies out of 856 identified publications through data base searches were included. The pooled prevalence of diabetes in patients with BP was 20.0% [95% CI 14%–26%; p = 0.00]. Within the comparative non-BP control population, 13% had diabetes. BP patients were more likely to have diabetes compared to a control population without BP [OR 2.10, 95% CI 1.22–3.60; p = 0.01]. This study found that twice the number of BP patients have DM (20%) compared to the general population reported as 10.5%, warranting monitoring of blood glucose levels in BP patients who may have yet undeclared or undiagnosed DM when initiating systemic steroids.