Differences in Comorbidity Profiles Between Early-Onset and Late-Onset Alopecia Areata Patients: A Retrospective Study of 871 Korean Patients

Background: Alopecia areata (AA) is a common dermatologic condition with a broad spectrum of clinical features and age of onset, classically characterized by nonscarring patches of hair loss. In the past, early-onset (before adolescence) AA has been associated with various autoimmune diseases, especially atopic diseases and lupus erythematosus and demonstrates a worse prognosis compared with late onset AA. Objective: To evaluate the differences in the comorbidity profile of AA with regard to age at onset. Methods: We completed a retrospective study of 871 Korean AA patients seen at our department within the last 10 years. After these patients were subdivided according to onset before or after age 13 years, the two groups were compared on the basis of their comorbid disorders, family history of AA, and hematologic test results. Results: Our results demonstrate that significantly more patients in the early-onset group had a personal history of atopic dermatitis or family history of AA. These findings are consistent with previous reports associating early-onset AA with autoimmune diseases and a family history of AA in different ethnic populations. Most of the serologic test values showed no significant differences between the groups and the results were considerably affected by age. Conclusion: This study is significant because it is a large group study in Korean AA patients, and Korean AA patients with an onset age before adolescence show similar clinical manifestations to other ethnic populations.