Prevalence of Alopecia Areata in Saudi Arabia: Cross-Sectional Descriptive Study.

Background Alopecia areata (AA) is a common autoimmune disorder worldwide that affects the hair. Population differences have been observed in disease prevalence and clinical features, but no studies have examined AA prevalence at a large scale. In Saudi Arabia, information is lacking about AA characteristics. Objectives A quantitative, observational, cross-sectional study was conducted to assess AA prevalence, characteristics, and gender differences in Saudi Arabia. Materials and methods The study has used a validated Arabic questionnaire that targeted Saudi Arabia residents with a history of AA. A validated Arabic questionnaire was used to target Saudi Arabia residents with a history of AA, and the data collection instrument and written informed consent were distributed on Twitter and Facebook after permission from the Institutional Review Board. Prior to the study, accuracy validation for correct diagnosis by participants was performed in a 50-volunteer pilot test, which indicated an acceptable level of 96% accuracy. The questionnaire included high-quality images of different AA types and the collected data focused on variables such as the age of onset, affected body parts, treatment type, and family history of AA. Results A total of 5,362 participants returned completed questionnaires, of whom 741 (13.8%) had experienced AA at least once in their lives. Most were aged 11-30 years (69%), and the mean age of diagnosis was 18.6 years. Thirty-six percent (36%) of those with AA reported having a first-degree relative with the disease, and cross-sectional prevalence was 5.2%. Three-hundred fifty-nine (359; 18.9%) males and 382 (11%) females had AA. Twenty-nine point four percent (29.4%) of AA patients recovered in less than three months of AA onset, and 59.4% recovered in less than one year. Conclusion AA prevalence in Saudi Arabia is higher than in Western countries with a lower age of onset than in the former. AA affected males more than females and the mean age of onset was lower in the latter. Both male gender and young age of onset implied a worse prognosis.