Prevalence of thyroid eye disease in Graves' disease: A meta-analysis and systematic review

Objective Thyroid eye disease (TED) is a debilitating condition that frequently manifests in patients suffering from Graves' disease (GD). This study aims to analyse the prevalence of TED among GD patients, with a focus on geographical region-specific rates. Methods Medline and Embase were searched for articles examining TED prevalence on April 2020, and articles were retrieved and sieved. Statistical analysis was performed after Freeman-Tukey double arcsine transformation. Thereafter, results were pooled with random effects by DerSimonian and Laird model. Results Fifty-seven articles involving 26,804 patients were included in the review. The overall pooled prevalence of TED was 40% (CI: 0.32 to 0.48) and by continent was 38% (CI: 0.31 to 0.46) for Europe, 44% (CI: 0.32 to 0.56) for Asia, 27% (CI: 0.06 to 0.56) for North America and 58% (CI: 0.55 to 0.61) for Oceania. The prevalence of TED in Southeast Asia was 35% (CI: 0.24 to 0.47) and Middle East 48% (CI: 0.19 to 0.78). Subgroup analysis showed regions with predominantly Caucasians (37%; CI: 0.28 to 0.46) had a lower prevalence of TED compared to Asians (45%; CI: 0.33 to 0.58). The pooled prevalence of lid retraction was 57% (CI: 0.39 to 0.74), proptosis 57% (CI: 0.48 to 0.65), diplopia 36% (CI: 0.24 to 0.48) and ocular hypertension 13% (CI: 0.06 to 0.19). Conclusion A substantial proportion of patients with GD have TED and often manifest as lid retraction, proptosis and diplopia. Early detection through active screening might help to mitigate the progression of TED and its associated complications.