Endocrine Abstracts

Background: Success of Graves’ orbitopathy (GO) immunosuppression treatment is highly variable; patients relapse and a debilitating residual disease burden often remains with current therapies. This study describes the outcomes of immunosuppression in a multi-ethnic GO cohort treated in accordance with pre-2021 European Group on GO (EUGOGO) guidelines with first-line intravenous-methylprednisolone (IVMP). This study aims: (1) To evaluate the effect of first-line and additional immunosuppression on GO outcomes; (2) To assess the effect of immunosuppression on Graves-Orbitopathy-Quality-of-Life (GOQOL); (3) To determine the incidence of GO-relapse and predictive factors of relapse.

Methods: A retrospective study of patients who received IVMP first-line therapy at three MDT clinics between 2011-2021. Data was collected at the first, and most recent, appointment. This included: (1) demographics; (2) endocrine parameters; (3) MDT-clinic data (Clinical Activity Score [CAS], Gorman Diplopia, GOQOL, GO-treatment, relapse). First-clinic appointment data was compared between relapse and non-relapse patients.

Results: 146/438 (33%) patients were included; median-age 50 (18-59) years. 77.4% were female; 42.8% Afro-Caribbean or Asian ethnicity. Fifty-four patients received IVMP alone; eighty-seven patients had additional immunosuppression with MMF or orbital radiotherapy (ORT). Median CAS was significantly reduced from 3(2.5-4.0) to 0(0.0-1.0)(P<0.0001). Mean Gorman demonstrated an insignificant decrease from 1.2(±1.1) to 0.9(±1.1); twenty-seven (36.5%) patients achieved a clinically-significant diplopia response. Mean GOQOL visual-function and appearance scores increased by 8.3 and 9.2 (P=0.03) respectively. Thirty-eight (26.0%) patients relapsed. Baseline thyroid-stimulating hormone receptor antibodies (TRAb) levels were significantly higher with GO-relapse (P=0.0039). An antibody titre cut-off of 5.25 iu/l yielded 73% sensitivity and 67% specificity to detect GO-relapse.

Conclusions: Our study shows that the pre-2021 EUGOGO immunosuppression regimen is effective in reducing orbital inflammation but limited in improving subjective diplopia and appearance, which is likely to hinder QOL improvement. Our study found higher TRAb levels were associated with disease relapse.