Alopecia areata morbidity structure considering the association with atopic dermatitis in the population of Moscow in comparison with data from the federal register

Background. Alopecia areata (AA) is an autoimmune disease in which association with atopic dermatitis (AD) is one of the prognostically adverse factors. The relevance of studying the structure of AA morbidity taking into account atopic comorbidity is caused by the lack of modern epidemiological data and age differences in clinical manifestations. Objective. To study the structure of AA morbidity in the population of Moscow and the federal register with emphasis on association with AD. Material and methods. A multicenter retrospective cohort study was carried out on the basis of data from the Moscow Scientific and Practical Center of Dermatovenereology and Cosmetology (MSPCDC) and the register of adult patients with AA for 2020—2024. The analysis included stratification according to ICD-10 (L63.0—L63.8), age groups (children aged 0—17 years and adults aged 18 years and older), assessment of association with AD (L20.8), calculation of extensive and intensive indicators (per 100 000 population). Methods of descriptive and analytical statistics were used: logistic regression, χ² and Mann—Whitney U tests, Bonferroni correction. Results. Prevalence of local forms (L63.8—84.9%) with a steady increase in their proportion (+3.2 p.p., p<0.001) especially among children (+8.6 p.p.) was revealed. Severe forms (L63.0—L63.2) amounted to 15.1%, more frequently occurring in children (15.2% versus 12.6%, p<0.05), especially ophiasis (1.7 times more frequent, p=0.013). Association with AD was noted in 2.7% of patients with maximum increase in children (+2.2 p.p., p=0.013). For comorbidity with AD, alopecia totalis (18.2% versus 8.1% in the overall group, OR 2.47, p<0.001) and universalis (7.4% versus 3.0%, OR 2.41, p=0.003) predominated. In the register (n=403), AD was diagnosed in 15.9% of patients predominantly with alopecia universalis (27.9%, OR 4.2, p<0.001). Conclusion. The significant association of severe forms of AA with AD emphasizes the importance of considering the atopic background in assessing the clinical course of alopecia.