Supplementary Material for: Prevalence of thyrotropin receptor antibodies and clinical profile of patients with alopecia areata: A cross-sectional study

Introduction: Alopecia areata (AA) is associated with thyroid dysfunction and abnormal levels of thyroglobulin and thyroid peroxidase autoantibodies. One study detected high prevalence of thyrotropin receptor antibodies (TRAb) in AA patients. Our aim was to investigate the prevalence of TRAb levels in AA patients and to assess their association with thyroid hormones, other thyroid antibodies, AA severity, and other epidemiological variables.
Methods: In this observational study, 139 patients (97 females, 42 males), aged 12 and above, with newly presenting, relapsing, or treatment-resistant AA were included. Medical histories were reviewed, alopecia severity was assessed using the Severity of Alopecia Tool (SALT), and blood tests measured thyroid hormones and autoantibodies.
Results: The prevalence of TRAb was significantly higher in AA patients (23.6%) compared to the general population (1-2%) (P<0.001). Elevated TRAb titers did not correlate with diagnosed thyroid dysfunction or treatment, abnormal thyroid function tests and autoantibodies, AA severity, duration and onset. Male patients exhibited a significantly higher prevalence of abnormal TRAb titers compared to females (75.0% vs. 21.3%, P=0.002).
Conclusion: A significant proportion of AA patients presented with elevated TRAb levels, independent of thyroid hormone titers, other thyroid autoantibodies, or SALT score. Prevalence of abnormal TRAb levels was higher in males.

引言：斑秃（Alopecia areata, AA）与甲状腺功能紊乱、甲状腺球蛋白及甲状腺过氧化物酶自身抗体水平异常存在关联。既往研究已在斑秃患者中检出促甲状腺素受体抗体（thyrotropin receptor antibodies, TRAb）的高患病率。本研究旨在探究斑秃患者的促甲状腺素受体抗体水平检出率，并评估其与甲状腺激素、其他甲状腺自身抗体、斑秃严重程度及其他流行病学变量之间的关联。
方法：本项观察性研究纳入了139例年龄≥12岁的斑秃患者，其中女性97例、男性42例，均为初发、复发或治疗抵抗性斑秃。研究回顾了受试者的既往病史，采用斑秃严重程度量表（Severity of Alopecia Tool, SALT）评估脱发严重程度，并通过血液检测测定甲状腺激素与自身抗体水平。
结果：斑秃患者的促甲状腺素受体抗体检出率为23.6%，显著高于普通人群的1%~2%（P<0.001）。升高的促甲状腺素受体抗体滴度与确诊甲状腺功能异常、治疗干预、甲状腺功能检测异常、自身抗体异常、斑秃严重程度、病程及起病情况均无显著相关性。男性患者的促甲状腺素受体抗体异常检出率显著高于女性（75.0% vs. 21.3%，P=0.002）。
结论：相当比例的斑秃患者存在促甲状腺素受体抗体水平升高的情况，且该表现与甲状腺激素滴度、其他甲状腺自身抗体或SALT评分无关。男性患者的促甲状腺素受体抗体异常检出率更高。