Prospective Assessment of Glucocorticoid Toxicity in Rheumatology Practice: A Focus on the Glucocorticoid Toxicity Index.

Objective: The glucocorticoid toxicity index (GTI) is developed to measure glucocorticoid (GC)-related morbidity over time. This study aimed to assess GC-toxicity in patients at a rheumatology outpatient clinic by using the GTI and to identify the factors that interfere with the GTI.

Methods: This prospective study included patients with inflammatory arthritis (IA), connective tissue disease, and vasculitis who were newly prescribed GC-treatment (GC-naive) or have been still on GC-treatment for ≤2 years (GC-experienced). Patient demographics and disease characteristics, aggregate improvement score (GTI-AIS), cumulative worsening score (GTI-CWS), and cumulative GC-doses were recorded at baseline, 3rd month, and 6th month. Generalized estimating equations (GEE) were used to evaluate the GTI scores and associated factors including cumulative GC-doses.

Results: The study included 156 (48.7% GC-naive) patients with a mean age of 49.1 ± 17.1 years. More than half of the patients in both groups had a diagnosis of vasculitis. A higher cumulative GC-dose was found to be associated with higher GTI-scores in both groups (p< 0.001). In the GC-naive group, patients with vasculitis showed higher GTI-scores than IA patients (p< 0.001); there was also a significant increase in the GTI-CWS at the 6th month compared with the 3rd month. In the GC-experienced group, GTI-AIS and GTI-CWS were significantly different at 3rd and 6th month (p< 0.05).

Conclusion: It was shown that GTI scores were associated with cumulative GC-doses and vasculitis patients in the GC-naive patients had higher GTI scores than inflammatory arthritis. The GTI allows individualized assessment and management of adverse effects experienced by patients as a result of GC treatment.