Association of Patient Age and the Thyroid Eye Disease-Clinical Activity Score

Purpose: To investigate the association between age and clinical activity score (CAS) in patients with active, untreated thyroid eye disease.

Methods: A retrospective review was conducted of patients with active, untreated thyroid eye disease at a single institution between 2010 and 2020 whose ophthalmologic symptoms began no more than 9 months prior to the initial visit. Exclusion criteria included surgical or systemic thyroid eye disease treatment before or during the study period. Demographic and clinical data were collected for all patients, including a 7-point CAS at visit 1 (CAS1) and a 10-point score at visit 2 (CAS2). Patients were stratified by age: Group 1 (18-45), Group 2 (46-70), and Group 3 (71-85).

Results: A total of 156 patients were included: mean age 51.7 ± 15.8 years, 79.5% female. CAS1 differed significantly across groups: 1.9 ± 1.0 (Group 1), 2.7 ± 1.4 (Group 2), and 2.2 ± 1.6 (Group 3), p = 0.005. Findings were similar for CAS2: 2.2 ± 1.4 (Group 1), 3.0 ± 1.8 (Group 2), and 2.8 ± 1.9 (Group 3), p = 0.030. Post hoc analysis showed a statistically significant difference between Groups 1 and 2 (p = 0.004, visit 1; p = 0.025, visit 2) but not between other pairs. Patients with CAS1 of 0-3 (n = 129) were younger on average than those with CAS1 4-7 (n = 27): 50.4 ± 16.2 versus 58.2 ± 12.8 years (p = 0.009). Conjunctival redness (p = 0.019) and chemosis (p ≤ 0.001) were more common in older patients at both visits.

Conclusions: Patients aged 46-70 years with active, untreated thyroid eye disease had significantly higher CAS1 and CAS2 than younger patients in this study, largely driven by differences in conjunctival redness and chemosis.