Association of bullous pemphigoid and comorbid health conditions: a case–control study

Background: Bullous pemphigoid is an autoimmune skin disease characterized by the formation of blisters between the epidermis and dermis. Comorbidities of pemphigoid have not been well-described. Identification of comorbidities associated with pemphigoid is important to decrease morbidity and mortality. Objective: To identify the comorbid health conditions of bullous pemphigoid. Methods: This was a case–control study of 91 cases of pemphigoid verified by clinical and laboratory diagnosis and 546 age- and sex-matched controls with complete follow-up at a large metropolitan quaternary care medical center. Results: The average age of bullous pemphigoid patients was 76 years and 53% of patients were female. Forty-eight (53%) of the BP patients had a history of inpatient hospitalization, of which 22 (24.2%) were hospitalized for either previously undiagnosed BP or an exacerbation of BP. Bullous pemphigoid was significantly associated with hypertension [adjusted odds ratio (95% confidence interval)]: [2.03 (1.24–3.32)], diabetes mellitus [2.59 (1.60–4.19)], chronic kidney disease [2.29 (1.19–4.40)], end-stage renal disease [3.82 (1.48–9.85)], basal cell carcinoma of the skin [6.00 (1.94–18.6)], and obstructive sleep apnea [5.23 (2.45–11.19)]. 78% of BP patients used at least one systemic immunosuppressant. There was no significant association between treatments for pemphigoid and any of the comorbidities. Conclusions: Bullous pemphigoid patients need screening for comorbid health conditions even though treatment options do not seem to be associated with these comorbidities.