Prevalence, comorbidities, and treatment patterns of Japanese patients with alopecia areata: A descriptive study using Japan medical data center claims database

This study analyzed the prevalence, comorbidities, and treatment patterns of alopecia areata (AA) in Japan using data from the Japan Medical Data Center claims database from 2012 to 2019. It included 61,899 patients diagnosed with AA, with 1,497 having severe subtypes. The prevalence of AA in Japan increased from 0.16% in 2012 to 0.27% in 2019. Common comorbidities included allergic rhinitis, atopic dermatitis, asthma, depression, anxiety, and autoimmune diseases like vitiligo and thyroid diseases. Down syndrome was notably associated with severe AA in children. Treatments primarily involved topical corticosteroids, with systemic corticosteroids and antihistamines used more in severe cases. Despite guidelines advising against oral corticosteroids in children, they were prescribed in some pediatric cases. The study highlighted a growing prevalence of AA and a need for effective therapies, particularly for severe and pediatric cases.