Chronic disease associated with bullous pemphigoid risk: A systematic review and meta-analysis

Background: Bullous pemphigoid (BP) is a chronic autoimmune blistering disease prevalent in the elderly, often accompanied by renal comorbidities. Immune dysregulation can lead to secondary BP and increased mortality rates in those already diagnosed. Methods: A literature review identified studies on the association between kidney disease and other comorbidities with BP. Pooled effect estimates were analyzed utilizing a random-effects model. Objective: To assess comorbidity risks with BP and determine mortality risk among BP patients with comorbidities. Results: Analysis included 45,323 BP patients from 49 studies. Kidney diseases were significantly linked to higher BP incidence (subdistribution hazard ratio 1.51, 95% CI: 1.10-2.07) and increased mortality (hazard ratio 1.62, 95% CI: 1.13-2.32). Cerebrovascular diseases, dementia, and diabetes also showed significant associations with both increased BP incidence and mortality (P < .05). However, cardiovascular diseases and malignancy were only associated with increased mortality among BP patients (P < .001) without affecting BP incidence (P = .785 and P = .792, respectively). Limitation: The study comprises mostly case-control, prospective, and retrospective observational studies, alongside data heterogeneity. Conclusion: This study reveals the association of several chronic conditions, including kidney diseases, with BP, contributing to elevated mortality rates. The findings emphasize the importance of management targeting both BP and associated comorbidities to improve patient outcomes.