The risk of Coronavirus disease 2019 (COVID-19) in patients with bullous pemphigoid and pemphigus: A population-based cohort study

Kridin, Khalaf; Schonmann, Yochai; Weinstein, Orly; Schmidt, Enno; Ludwig, Ralf J.; Cohen, Arnon D.

Background The burden of Coronavirus disease 2019 (COVID-19) in patients with bullous pemphigoid (BP) and pemphigus is yet to be evaluated. Objective To assess the risk of COVID-19, and COVID-19-associated hospitalization and mortality in patients with BP and pemphigus, and to delineate determinants of severe COVID-19 illness among these patients. Methods A population-based cohort study was performed to compare patients with BP (n=1,845) and pemphigus (n=1,236) with their age-, sex- and ethnicity-matched control subjects regarding COVID-19 and its complications. Results The risk of COVID-19 (HR, 1.12; 95%CI, 0.72-1.73; P=0.691) and COVID-19-associated hospitalization (HR, 1.58; 95%CI, 0.84-2.98; P=0.160) was comparable between patients with BP and controls, whereas the risk of COVID-19-associated mortality was higher among patients with BP (HR, 2.82; 95%CI, 1.15-6.92; P=0.023). The risk of COVID-19 (HR, 0.81; 95%CI, 0.44-1.49; P=0.496), COVID-19-associated hospitalization (HR, 1.41; 95%CI, 0.53-3.76; P=0.499), and COVID-19-associated mortality (HR, 1.33; 95%CI, 0.15-11.92; P=0.789) was similar in patients with pemphigus and their controls. Systemic corticosteroids and immunosuppressants did not predispose COVID-19-positive BP and pemphigus patients to a more severe illness. Limitations Retrospective data collection. Conclusions BP patients experience increased COVID-19-associated mortality and should be monitored closely. Maintaining systemic corticosteroids and immunosuppressive adjuvant agents during the pandemic.is not associated with worse outcomes.