VARIABLES AFFECTING THE LONG TERM OUTCOME OF GRAVES' ORBITOPATHY FOLLOWING HIGH DOSE INTRAVENOUS GLUCOCORTICOID PULSE THERAPY IN PATIENTS NOT TREATED WITH ORBITAL RADIOTHERAPY.

Objective Intravenous (iv) glucocorticoids (GC) (ivGC) are used for active Graves' orbitopathy (GO), but factors affecting GO outcome are poorly known. Here we performed a retrospective study aimed at investigating the variables affecting GO after ivGC. Methods We evaluated 83 consecutive GO patients treated with ivGC, but not with orbital radiotherapy, and re-examined them after a median period of 47 months. The end-points were the relation between GO outcome or additional treatments with age, gender, smoking, thyroid volume, thyroid treatment, time since thyroid treatment, TRAb, GO duration, GO features and follow-up time. Results GO features improved after treatment, resulting in a moderate and a marked amelioration in ~75% and ~41% of patients respectively. By multivariate analysis a moderate GO improvement correlated with diplopia at first observation, which was more severe in responders. A marked GO improvement correlated with time between first and last observation and time after thyroid treatment, which were longer in responders. This likely reflected the combination of an early effect of GC and a late, spontaneous improvement of GO, as shown by analysis of GO outcome at various time points. Additional treatments after ivGC correlated by multivariate analysis with eyelid aperture, diplopia and NOSPECS score at first observation, which were more severe in responders. Conclusions Our study shows that response to ivGC increases with time, likely reflecting the known tendency of GO to improve spontaneously, and is more pronounced when GO is more severe to begin with, which is associated with more additional treatments.