Acquired Alopecias in Mexican Adults: A Clinical and Epidemiological Study of 1,888 Patients

Hair loss has emerged as one of the most common reasons for dermatological consultations; however, reported epidemiological data remain variable.

This study aims to describe the types and clinical-epidemiological characteristics of acquired alopecia in adult patients.

A retrospective analysis was conducted on patients diagnosed with acquired alopecia at the Instituto Dermatológico de Jalisco "Dr. José Barba Rubio" between January 1, 2018, and December 31, 2022.

A total of 1,888 cases of acquired alopecia were analyzed, representing the largest case series reported nationally to date. The mean age of the patients was 37.07 years. Female patients accounted for 1,065 cases (56.4%), while male patients represented 823 cases (43.6%). Overall, alopecia areata was the most frequent type, accounting for 871 cases (46.13%), followed by androgenetic alopecia (543 cases, 28.76%) and traction alopecia (127 cases, 6.73%). Non-scarring alopecias comprised 1,661 cases (88.0%) of the studied population, whereas scarring alopecias accounted for 227 cases (12.0%). Among scarring alopecias, cases with neutrophilic or mixed inflammatory infiltrates predominated, accounting for 145 cases (63.98%), with a higher prevalence among male patients. In this study, folliculitis decalvans was identified as a major cause of scarring alopecia in the Mexican population, accounting for 64 cases (3.39%) of all alopecia cases in the cohort.

Regional studies are essential to better understand alopecia patterns and to guide tailored diagnostic and management strategies for affected patients.