Knowledge of Thyroid Eye Disease in Graves' Disease Patients With and Without Orbitopathy

Thyroid eye disease (TED) develops in around 25% of those with Graves' disease (GD). Patients with TED may present late to ophthalmologists, when debilitating orbital inflammatory changes have already occurred. The reasons for this are multifactorial, but poor knowledge of TED in GD patients may be contributory. This study aimed to assess the knowledge of TED in those with established TED, GD without orbitopathy, and control subjects.

A validated, anonymized questionnaire, with 20 knowledge-based questions, was prospectively completed by 100 GD patients, 100 TED patients, and 100 age- and sex-matched controls (with no history of thyroid disease or TED) in two tertiary referral thyroid and orbital diseases clinics. Demographic data and details of highest educational level, disease duration, and follow-up were gained. Residence postcode was used to determine Index of Multiple Deprivation (2015) quintile. Knowledge score was established for each of the study groups of interest. Statistical analysis was undertaken with Kruskal-Wallis test, chi-square test, and multivariable logistic regression.

There was no significant difference in median knowledge scores (out of 20) between GD (13.71, range 9-18) and TED (14.25, range 9-18) patients. However, both groups had significantly higher scores than controls (11.53, range 4-16; p < 0.001). Multivariable analysis determined no particular independent factor associated with lower knowledge score. There were a number of important areas in which patient knowledge of TED was poor. While almost all (99% TED, 89% GD) knew that TED involved orbital tissue inflammation, a large proportion (60% TED, 50% GD) were unaware that TED may develop in the absence of hyperthyroidism or did not know that cigarette smoking is associated with more severe TED (21%TED, 33% GD).

TED patients had equivalent levels of TED knowledge compared to GD patients without orbitopathy. While subjects in both disease groups had greater knowledge than controls, each had significant misconceptions regarding aspects of TED diagnosis, management, and treatment. These findings should guide the future provision of patient information for TED, with educational materials being targeted to address existing gaps in knowledge.