Ahmed Yousaf1, Justin Lee1, Wei Fang2, Michael S Kolodney1. 1. Department of Dermatology, West Virginia University, Morgantown. 2. West Virginia Clinical and Translational Science Institute, Morgantown.
Abstract
IMPORTANCE: Alopecia areata (AA) is a complex immune-mediated disorder that causes nonscarring hair loss. Previous reports have documented preferential targeting of pigmented hair follicles with sparing of gray, nonpigmented hair follicles in alopecia lesions. Thus, immune targeting of melanogenesis-associated proteins in melanocytes and keratinocytes represents a potential mechanism for the inflammation that targets anagen hairs in alopecia areata. OBJECTIVE: To investigate the association of alopecia areata with hair color among White residents of the UK. DESIGN, SETTING, AND PARTICIPANTS: This matched, case-control study conducted in October 2020 used a large prospectively acquired cohort and included data that were collected from the UK Biobank, a large-scale prospective resource designed to study phenotypic and genotypic determinants in adults. A total of 502 510 UK Biobank participants were reviewed for inclusion. Among these individuals, 1673 cases of alopecia areata with reported hair color were captured and matched by age and sex to 6692 controls without alopecia areata using 1:4 matching. MAIN OUTCOMES AND MEASURES: Conditional logistic regression analysis was performed, in which the outcome variable was alopecia areata and the main predictor was natural hair color before graying. The variables considered included diabetes, hypothyroidism, hyperthyroidism, and vitiligo. RESULTS: Of 464 353 participants, 254 505 (54.8%) were women, and the mean (SD) age for those with alopecia areata was 46.9 (16.5) years. Alopecia areata was significantly more common in individuals with black (adjusted odds ratio [aOR], 2.97; 95% CI, 2.38-3.71) and dark brown hair (aOR, 1.26; 95% CI, 1.11-1.42) compared with light brown hair. In contrast, blond individuals exhibited significantly decreased alopecia areata compared with those with light brown hair (aOR, 0.69; 95% CI, 0.56-0.85). Red hair color was not significantly different from light brown hair. CONCLUSIONS AND RELEVANCE: The findings of this matched case-control study seem to indicate that alopecia areata is modulated by natural hair color, preferentially targeting darker hair. Our results support a previously proposed model of alopecia areata in which immunity is directed against melanogenesis-associated proteins in the anagen hair follicles. However, further study is needed to more precisely understand the immunopathogenic association between alopecia areata and hair color.
IMPORTANCE: Alopecia areata (AA) is a complex immune-mediated disorder that causes nonscarring hair loss. Previous reports have documented preferential targeting of pigmented hair follicles with sparing of gray, nonpigmented hair follicles in alopecia lesions. Thus, immune targeting of melanogenesis-associated proteins in melanocytes and keratinocytes represents a potential mechanism for the inflammation that targets anagen hairs in alopecia areata. OBJECTIVE: To investigate the association of alopecia areata with hair color among White residents of the UK. DESIGN, SETTING, AND PARTICIPANTS: This matched, case-control study conducted in October 2020 used a large prospectively acquired cohort and included data that were collected from the UK Biobank, a large-scale prospective resource designed to study phenotypic and genotypic determinants in adults. A total of 502 510 UK Biobank participants were reviewed for inclusion. Among these individuals, 1673 cases of alopecia areata with reported hair color were captured and matched by age and sex to 6692 controls without alopecia areata using 1:4 matching. MAIN OUTCOMES AND MEASURES: Conditional logistic regression analysis was performed, in which the outcome variable was alopecia areata and the main predictor was natural hair color before graying. The variables considered included diabetes, hypothyroidism, hyperthyroidism, and vitiligo. RESULTS: Of 464 353 participants, 254 505 (54.8%) were women, and the mean (SD) age for those with alopecia areata was 46.9 (16.5) years. Alopecia areata was significantly more common in individuals with black (adjusted odds ratio [aOR], 2.97; 95% CI, 2.38-3.71) and dark brown hair (aOR, 1.26; 95% CI, 1.11-1.42) compared with light brown hair. In contrast, blond individuals exhibited significantly decreased alopecia areata compared with those with light brown hair (aOR, 0.69; 95% CI, 0.56-0.85). Red hair color was not significantly different from light brown hair. CONCLUSIONS AND RELEVANCE: The findings of this matched case-control study seem to indicate that alopecia areata is modulated by natural hair color, preferentially targeting darker hair. Our results support a previously proposed model of alopecia areata in which immunity is directed against melanogenesis-associated proteins in the anagen hair follicles. However, further study is needed to more precisely understand the immunopathogenic association between alopecia areata and hair color.
Authors: Johannes Fischer; Franziska Degenhardt; Andrea Hofmann; Silke Redler; F Buket Basmanav; Stefanie Heilmann-Heimbach; Sandra Hanneken; Kathrin A Giehl; Hans Wolff; Susanne Moebus; Roland Kruse; Gerhard Lutz; Bettina Blaumeiser; Markus Böhm; Natalie Garcia Bartels; Ulrike Blume-Peytavi; Lynn Petukhova; Angela M Christiano; Markus M Nöthen; Regina C Betz Journal: Exp Dermatol Date: 2017-03-23 Impact factor: 3.960
Authors: Pirro G Hysi; Ana M Valdes; Fan Liu; Nicholas A Furlotte; David M Evans; Veronique Bataille; Alessia Visconti; Gibran Hemani; George McMahon; Susan M Ring; George Davey Smith; David L Duffy; Gu Zhu; Scott D Gordon; Sarah E Medland; Bochao D Lin; Gonneke Willemsen; Jouke Jan Hottenga; Dragana Vuckovic; Giorgia Girotto; Ilaria Gandin; Cinzia Sala; Maria Pina Concas; Marco Brumat; Paolo Gasparini; Daniela Toniolo; Massimiliano Cocca; Antonietta Robino; Seyhan Yazar; Alex W Hewitt; Yan Chen; Changqing Zeng; Andre G Uitterlinden; M Arfan Ikram; Merel A Hamer; Cornelia M van Duijn; Tamar Nijsten; David A Mackey; Mario Falchi; Dorret I Boomsma; Nicholas G Martin; David A Hinds; Manfred Kayser; Timothy D Spector Journal: Nat Genet Date: 2018-04-16 Impact factor: 38.330