Demographic and Clinical Features of 1,641 Patients with Alopecia Areata, Alopecia Totalis, and Alopecia Universalis: A Single-Center Retrospective Study

Background/Aim: Alopecia areata (AA) is a common autoimmune hair disorder which is characterized by noncicatricial hair loss. AA commonly presents with localized patches on the scalp and face but may affect any hair-bearing region of the body leading to even more generalized involvement. AA may affect any age group, gender, and race. The current study investigates the demographic characteristics of the patients with AA and subgroups of AA including alopecia totalis (AT) and alopecia universalis (AU) and the prevalence of disease, sex, and age distribution and seasonal variation retrospectively in a tertiary dermatology clinic in Turkey. Materials and Methods: In this retrospective, cross-sectional study, 1,641 patients diagnosed with AA, AT, and AU in the dermatology clinic of a public university hospital were included. The dermatology outpatient database was reviewed retrospectively. The diagnosis of AA was based on patient history, clinical examinations, and histopathologic findings. Results: Fifty-four thousand one hundred sixty-eight patients were admitted to our outpatient clinic in 4 years time, and 1,641 were diagnosed as having AA, AT, and AU. One thousand three hundred ninety-two patients (84.8%) had AA, 81 (4.9%) had AT, and 168 (10.2%) had AU. Among the 1,641 patients included in the study, 877 were females (53.4%) and 764 were males (46.6%). The mean age was 29.86 +/- 14.48 years in AA, 29.50 +/- 16.18 in AT, and 32.81 +/- 14.48 in AU; 77.4, 72.8, and 68.5% of patients were aged under 40 years in AA, AT, and AU. There was no statistically significant difference in seasonal presentation times. Conclusion: AA is affecting approximately 2% of the general population without any sex, race, or age group predilection. In this study, we found a lower prevalence of AA in the pediatric age group in comparison with adults. This finding may support the hypothesis of the increasing prevalence of AA over time. The higher ratio of AA regarding this study may support that the frequency of AA and subtypes varies between regions.