Increased incidence and healthcare burden of bullous pemphigoid: A population‐based cohort study

BACKGROUND: Bullous pemphigoid (BP) is the most common autoimmune blistering disease and primarily affects older adults. As societies age and the burden of age-related diseases increases, data on BP epidemiology, treatment patterns and healthcare burden in Germany remain limited. OBJECTIVES: To assess BP epidemiology, clinical outcomes, healthcare utilization and economic burden in adults aged ≥ 18 years in Germany. METHODS: We analysed anonymized statutory health insurance claims from 6.8 million insured individuals (2010-2023). Annual cross-sectional analyses estimated prevalence and incidence, extrapolated to the national population. In a matched incident cohort (BP, n = 2004; controls, n = 9950), we evaluated comorbidity, mortality, healthcare resource utilization, healthcare costs and pharmacologic management over up to 2 years. Mortality and costs were analysed using regression models adjusted for age, sex, calendar year, and comorbidity. RESULTS: BP prevalence tripled from 0.05 to 0.14 cases per 1000 individuals between 2010 and 2023, with the steepest increase observed among individuals aged ≥ 80 years. Annual incidence ranged from 34 to 63 cases per million inhabitants. BP patients exhibited a higher comorbidity burden than matched controls (mean Elixhauser index 5.0 vs. 3.8) and increased mortality (1-year mortality: 18.8% vs. 6.0%; adjusted incidence rate ratio (IRR) 3.09, 95% CI: 2.71-3.52). Healthcare utilization was higher among BP patients, including physician contacts (38 vs. 22 per year) and hospital admissions (3.3 vs. 0.7 per year). Topical and systemic corticosteroids were prescribed in 75% and 72% of patients, respectively; additional therapies included doxycycline (19.7%), dapsone (15.0%) and azathioprine (14.8%). Mean total healthcare costs during the first year were €20,881 for BP patients versus €5586 for controls, mainly attributable to inpatient care. CONCLUSIONS: BP represents a growing healthcare challenge characterized by a high comorbidity burden, increased mortality and healthcare costs. Current treatment remains reliant on systemic corticosteroids, underscoring the need for safe and effective steroid-sparing therapies.