Ethnic variation in clinical and imaging features of thyroid eye disease.

Purpose: To evaluate ethnic differences in thyroid eye disease (TED).Methods: Retrospective study of adults with TED at a tertiary center (2018-2025). Data included self-reported race/ethnicity, thyroid history, smoking, clinical features, serology, orbital imaging, and treatment. The more proptotic orbit was analyzed (right if symmetrical). Orbital areas were measured in a standardized fashion immediately posterior to the globe. Patients were categorized as non-Hispanic White (W), Asian (A), Black (B), and Hispanic (H). Statistical tests included χ2 -tests and ANOVA.Results: 354 patients were included: (W: n = 170, A: n = 76, B: n = 29, H: n = 77). A (46.5 ± 15.3 years) and H (46.1 ± 16.3 years) presented > 10 years earlier than W (58.2 ± 15.2 years; p < .001) and had shorter intervals from thyroid diagnosis to TED (A 79.4 ± 117.5, H 89.4 ± 107.8; W 157.2 ± 117.5, B 131.3 ± 177.4 months; p < .001). Smoking was lowest in A (p = .01). Diplopia (46.4%, p = .001) and strabismus surgery (22.9%, p = .01) was most common in W. B and H exhibited greater exophthalmos (B 22.8 ± 3.2 mm, H 22.1 ± 3.1 mm) than W and A (21.3 ± 3.6 mm, 21.0 ± 3.2 mm; p = .04). CAS, lid retraction, optic neuropathy, serology, and use of corticosteroids, radiotherapy, teprotumumab, or decompression were comparable across groups with similar follow-up. Imaging showed ethnicity-dependent muscle enlargement at presentation. Medial and inferior recti were largest in B and smallest in A (p = .002, p = .05), with reciprocal FMR (highest in A, lowest in W).Conclusion: Across this large multiethnic cohort, TED manifestations varied by race/ethnicity, supporting distinct phenotypes. Integrating these patterns into evaluation can refine screening, counseling, and individualized surgical planning for diverse patient populations.