Hospitalization, inpatient burden and comorbidities associated with bullous pemphigoid in the U.S.A.

BACKGROUND: Bullous pemphigoid (BP) is associated with significant disability and comorbid health disorders that may lead to or result from hospitalization. However, little is known about the inpatient burden and comorbidities of BP. OBJECTIVES: To obtain data on the inpatient burden and comorbidities of BP in the U.S.A. METHODS: We analysed data from the 2002 to 2012 National Inpatient Sample, including a representative 20% sample of all hospitalizations in the U.S.A. (72 108 077 adults). RESULTS: The prevalence of hospitalization for BP increased from 25·84 to 32·60 cases per million inpatients from 2002 to 2012. In multivariate logistic regression models with stepwise selection, increasing age, nonwhite ethnicity, higher median household income, being insured with Medicare or Medicaid, and increasing number of chronic conditions were all associated with hospitalization for BP (P < 0·05 for all). The top three primary discharge diagnoses for patients with a secondary diagnosis of BP were septicaemia (prevalence 5·51%, 95% confidence interval 5·03-5·99), pneumonia (4·60%, 4·19-5·01) and urinary tract infection (3·52%, 3·15-3·89). Patients with BP also had numerous autoimmune, infectious, cardiovascular and other comorbidities. Interestingly, BP was associated with multiple neuropsychiatric disorders, including demyelinating disorders, dementias (presenile, senile, vascular and other), paralysis, neuropathy (diabetic, other polyneuropathy), Parkinson disease, epilepsy, psychoses and depression. The mean annual age- and sex-adjusted in-hospital mortality rate was significantly higher in patients with a secondary diagnosis of BP compared with no BP (2·9%, range 2·8-3·9% vs. 2·1%, range 1·9-2·2%). Significant predictors of mortality in patients with BP included increasing age, nonwhite ethnicity and insurance with Medicaid or other payment status (P < 0·05 for all). CONCLUSIONS: Hospitalization for BP increased significantly between 2002 and 2012. Moreover, there were significant ethnic and healthcare disparities with respect to hospitalization and inpatient mortality from BP.