Does early response to intravenous glucocorticoids predict the final outcome in patients with moderate-to-severe and active Graves' orbitopathy?

Purpose: Intravenous glucocorticoids (ivGCs) given as 12-weekly infusions are the first-line treatment for moderate-to-severe and active Graves' orbitopathy (GO), but they are not always effective. In this study, we evaluated whether response at 6 weeks correlated with outcomes at 12 (end of intervention) and 24 (follow-up) weeks, particularly in patients initially unresponsive.
Methods: Our database (Bartalena et al. J Clin Endocrinol Metab 97:4454-4463, 10), comprising 159 patients given three different cumulative doses of methylprednisolone (2.25, 4.98, 7.47 g) was analyzed, pooling data for analyses. Responses at 6 weeks were compared with those at 12 and 24 weeks using three outcomes: overall ophthalmic involvement [composite index (CI)]; quality of life (QoL); Clinical Activity Score (CAS). Responses were classified as "Improved", "Unchanged", "Deteriorated", compared to baseline.
Results: Deteriorated patients at 6 weeks for CI (n = 8) remained in the same category at 12 weeks and 7/8 at 24 weeks. Improved patients at 6 weeks for CI (n = 51) remained in the same category in 63% and 53% of cases at 12 and 24 weeks, respectively. Unchanged patients at 6 weeks (n = 100) eventually improved in 28% of cases (CI), 58% (CAS), 32% (QoL). There was no glucocorticoid dose-dependent difference in the influence of early response on later outcomes.
Conclusions: Patients who deteriorate at 6 weeks after ivGCs are unlikely to benefit from continuing ivGCs. Patients unresponsive at 6 weeks still have a significant possibility of improvement later. Accordingly, they may continue ivGC treatment, or, alternatively, possibly stop ivGCs and be switched to a second-line treatment.