What clinical evidence supports an autoimmune pathophysiology of alopecia areata?

Updated: Aug 06, 2020
  • Author: Chantal Bolduc, MD, FRCPC; Chief Editor: Dirk M Elston, MD  more...
  • Print

Clinical evidence favoring autoimmunity suggests that alopecia areata is associated with other autoimmune conditions, the most significant of which are thyroid diseases and vitiligo (see History). For instance, in a retrospective cross-sectional review of 2115 patients with alopecia areata who presented to academic medical centers in Boston over an 11-year period, comorbid autoimmune diagnoses included thyroid disease (14.6%), diabetes mellitus (11.1%), inflammatory bowel disease (6.3%), systemic lupus erythematosus (4.3%), rheumatoid arthritis(3.9%), and psoriasis and psoriatic arthritis (2.0%). Other comorbid conditions found included atopy (allergic rhinitis, asthma, and/or eczema; 38.2%), contact dermatitis and other eczema (35.9%), mental health problems (depression or anxiety; 25.5%), hyperlipidemia (24.5%), hypertension (21.9%), and GERD (17.3%). [7, 8]

In conclusion, the beneficial effect of T-cell subtype depletion on hair growth, the detection of autoantibodies, the ability to transfer alopecia areata from affected animals to nonaffected animals, and the induction of remission by grafting affected areas onto immunosuppressed animals are evidence in favor of an autoimmune phenomenon. Certain factors within the hair follicles, and possibly in the surrounding milieu, trigger an autoimmune reaction. Some evidence suggests a melanocytic target within the hair follicle. Adding or subtracting immunologic factors profoundly modifies the outcome of hair growth.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!