Glucocorticoid toxicity index in patients with systemic lupus erythematosus (preliminary data)

Objective: to investigate the contribution of glucocorticoids (GC) to the development of irreversible organ damage in patients with systemic lupus erythematosus (SLE) using the GC toxicity index (GTI).Material and methods. The study included 65 patients with SLE who met the 2012 SLICC classification criteria. GTI, disease activity according to the SLEDAI-2K index and the SLICC damage index (DI) were determined in all patients, and standard laboratory and immunological tests were performed.Results and discussion. Patients were predominantly female (n=56, 86%), median disease duration was 76 [2; 288] months, SLEDAI-2K – 8.8 [0; 26], DI SLICC – 1.0 [0; 5], DI SLICC >0 was found in 28 (43%) patients. The median duration of GC therapy during the disease period was 66.0 [0; 288] months, maximum dose of GC – 32.7 [0; 80] mg, median of total GC dose during intravenous administration was 2942 [0; 17 812.5] mg, GTI at the time of enrolment in the study – 19 [0; 37] points. GTI >0 was present in 47 (72%) of 65 patients. GTI correlated with disease duration (r=0.33; p<0.008); maximum dose of oral GCs (r=0.31; p><0.012); duration of GC use (r=0.35; p><0.005); DI SLICC (r=-0.43; p><0.0001). In patients with an average disease duration of more than 3 years, GTI>˂0.008); maximum dose of oral GCs (r=0.31; p˂0.012); duration of GC use (r=0.35; p˂0.005); DI SLICC (r=-0.43; p˂0.0001). In patients with an average disease duration of more than 3 years, GTI was significantly higher than in patients with a disease duration of 1–3 years (p=0.023).Conclusion. An GTI>0 was found in 72% of SLE patients, which increased significantly with disease duration. The GTI value was influenced by the duration of SLE, the duration of GC treatment and the maximum GC dose during the disease period. A statistically significant correlation was found between the GTI and the SLICC DI, allowing the GTI value to be used as an additional component in the assessment of the contribution of GCs to the development of irreversible organ damage in patients with SLE. It is recommended that GTI is assessed in all patients with SLE receiving long-term GC treatment for the purpose of dose adjustment.