THE ASSOCIATION BETWEEN ALOPECIA AREATA AND THYROID DISORDERS: A SYSTEMATIC REVIEW

Objectives: To investigate the association between alopecia areata (AA) and thyroid disorders through a systematic review of the existing literature. Methods: PubMed, MEDLINE, and Embase were systematically searched for relevant literature. Rayyan QRCI was employed throughout this comprehensive process. Results: Our results included twelve studies with a total of 101,757 patients diagnosed with AA and 67,824 (66.7%) were females. We reported multiple thyroid dysfunctions associated with AA, including autoimmune hypothyroidism and Hashimoto thyroiditis. All of the included studies demonstrated a bidirectional relationship between AA and thyroid dysfunctions.  Five studies reported that thyroid dysfunctions were the most associated comorbidity among AA patients. Two studies demonstrated that patients with thyroid autoimmunity (thyrotoxicosis, Graves disorders, and thyroiditis) have a higher risk of developing AA. Other two studies found that thyroid dysfunction was associated with increased AA severity and low response to treatments. Conclusion: Our review's findings are consistent with the theory that individuals with AA have a higher frequency of thyroid disease, indicating that AA patients ought to undergo thyroid disease screening. Thyroid function and thyroid autoantibodies should be more frequently evaluated in AA patients, even though there is no evidence of a causative relationship or interaction between AA and thyroid disease. It is necessary to conduct more research on potential pathways and interactions.

Keywords: alopecia areata; thyroid disorders; hypothyroidism; hyperthyroidism; hair loss; Systematic review.