Clinical Predictors of Steroid Resistance in Moderate‐to‐Severe Bullous Pemphigoid Patients: A 15‐Year Retrospective Study

Steroid resistance is a common phenomenon observed in the treatment of bullous pemphigoid (BP). Previous studies addressing steroid resistance in BP were limited and were mainly case reports or case series. This retrospective study aims to compare the clinical and laboratory characteristics of steroid-resistant bullous pemphigoid (SRBP) patients and steroid-sensitive bullous pemphigoid (SSBP) patients and to identify potential risk factors associated with SRBP at diagnosis. We retrospectively reviewed the medical records of patients with BP who were diagnosed between January 2010 and June 2024 at Peking Union Medical College Hospital. This study analyzed 126 BP patients with moderate-to-severe disease severity, including 27 SRBP patients and 99 SSBP patients. Compared to SSBP patients, SRBP patients were of younger age [59 (47-65) vs. 71 (59-78), p < 0.001], higher female proportion [20 (74.1%) vs. 37 (37.4%), p < 0.001], higher anti-BP180 autoantibodies levels [130.6 ± 43.4 U/mL vs. 84.3 ± 59.5 U/mL, p < 0.001], lower hemoglobin [128 (106-142) g/L vs. 140 (127-150) g/L, p = 0.011], and lower serum albumin levels [31.5 (25.0-38.0) g/L vs. 38.0 (34.0-43.0) g/L, p < 0.001]. Multivariate logistic regression analysis confirmed that younger age (OR, 0.921; 95% CI, 0.876-0.968; p = 0.001), female sex (OR, 0.189; 95% CI, 0.048-0.739; p = 0.017), and lower albumin levels (OR, 0.777; 95% CI, 0.677-0.892; p < 0.001) are independent risk factors for steroid resistance in BP patients. This study showed that younger age, female sex, and low levels of serum albumin were independent risk factors of steroid resistance in BP patients. Correcting low serum albumin levels may be a crucial strategy to reduce steroid resistance.