gms | German Medical Science

Introduction: The Glucocorticoid Toxicity Index (GTI) app measures changes in glucocorticoid-associated morbidity [1]. The GTI, which captures improvement as well as worsening in glucocorticoid (GC) toxicity, consists of two subscores. The Cumulative Worsening Score (CWS) only counts toxicities and is always a positive number or 0 (no toxicity). With the Aggregate Improvement Score (AIS), both improvement and worsening across domains are considered. If the overall GC toxicity has improved, the AIS has a negative value. Here, we aimed to evaluate the GTI as an instrument to assess GC toxicity using data from the prospective observational Charité Rh-GIOP study.

Methods: Patients with vasculitis or polymyalgia rheumatica were included if beginning GC or experiencing a flare requiring increased GC doses. Doses were calculated in prednisone (PRED) equivalents. Data relevant to the nine GTI domains were collected at the baseline visit (V1) and follow-up (V2). These included: medications for hypertension, hyperglycemia, and hyperlipidemia; body mass index; bone mineral density (BMD); and data pertaining to muscle strength, skin toxicity, neuropsychiatric effects, and infections. We used multivariate logistic regression models to examine the relationship of PRED dose to the likelihood of CWS worsening and AIS improvement.

Results: 37 patients of mean age 66.6 years (range: 40.5-81.7) were included. Diagnoses were: GCA (n=7), PMR (14), AAV (10), EGPA (4), and PAN (2). PRED dosing is shown in Table 1 [Tab. 1]. The mean CWS & AIS for the 37 patients were 34.8 and 11.1, respectively. 28 patients (76%) had CWSs >0, indicative of worsening toxicity. 21 (57%) had AISs >0, also consistent with overall GC toxicity worsening across domains. However, 13 (35%) had AISs in the negative range, indicating overall improvements in GC toxicity. BMD measurements worsened by at least 3% in 16 (43%) patients and improved by at least 3% in 9 (24%). Cumulative PRED doses correlated strongly with the CWS. For every 1000mg of PRED between V1 & V2, the risk of CWS increase rose by 79% (Table 2 [Tab. 2]).

Conclusion: The GTI captured changes in GC toxicity over time well, both improvement and worsening. Cumulative PRED dose correlated strongly with increase in the Cumulative Worsening Score.

Disclosures: Rh-GIOP is supported by a joint funding of Amgen, BMS, Celgene, Generic Assays, GSK, Hexal, Horizon Therapeutics, Lilly, medac, Mundipharma, Novartis, Pfizer, Roche, and Sanofi.