Comorbidities of bullous pemphigoid: A single-center retrospective case-control study from Turkey

Although significant associations between bullous pemphigoid (BP) and certain comorbidities, primarily subtypes of neurological disorders, have been reported in several populations, it has yet to be demonstrated whether a correlation exists between pre-existing comorbidities and serum titers of anti-BP180 and 230 immunoglobulin G (IgG) antibodies among BP patients. The aim of the current study is to investigate the demographic and clinical features of BP patients in a large series from Turkey, determine the prevalence of pre-existing neurological and systemic disorders, and assess the correlation between the existence of certain comorbidities and basal serum titers of anti-BP180 and 230 IgG autoantibodies. Thus, data from 145 BP patients diagnosed in the study's center between 1987 and 2017 were retrospectively analyzed and compared with 310 age- and sex-matched control subjects. The serum titers of anti-BP 180 and 230 IgG autoantibodies were compared between the patients with and without comorbidities and its subtypes among 55 patients with available serum basal anti-BP levels. Twenty-eight of the BP patients (19.3%) had already been diagnosed with at least one neurological disorder at the onset of BP. According to regression analysis, preexisting neurological disorders (p = 0.017), stroke (p = 0.017), and malignancies (p = 0.005) were found to be higher among the study's BP patients than the controls. The serum titers of anti-BP180 and 230 that were measured at the time of diagnosis were significantly higher in patients with neurological disorders than in patients without neurological disorders (p = 0.042; p = 0.018). Among the pre-existing comorbidities, neurological disorders, particularly stroke, and malignancies were found to be significantly connected to the occurrence of BP in the selected Turkish population. The high titers of serum anti-BP180 and 230 IgG antibodies at the time of BP diagnoses may highlight undiagnosed pre-existing neurological disorders by provoking suspicion.