QOL-01. RISK FACTORS FOR AND CONSEQUENCES OF PROLONGED DEXAMETHASONE USE IN PATIENTS WITH GLIOBLASTOMA (GBM)

BACKGROUND Dexamethasone is the primary treatment for tumor-associated edema. Prolonged use can have significant side effects and may negatively impact survival in GBM. Factors associated with steroid dependence and steroid associated side effects (SASEs) are not well established. METHODS We performed a retrospective study of patients with newly diagnosed, IDH-wildtype GBM at our center. Demographics, clinical and tumor characteristics, dexamethasone usage, and SASEs (infections, myopathy, hypertension, fractures, mood symptoms, weight gain, and hyperglycemia) were extracted through chart review. We compared survival outcomes (OS) between patients with and without steroid dependence. Risk factors for steroid dependence were identified through logistic regression analysis. RESULTS 39/92 (35.9%) patients developed steroid dependence. Of these, 26/39 (66.7%) were on steroids at the start of initial treatment. Patients who developed steroid dependence were older, more likely to have STR/biopsy, bilateral disease, KPS < 90, baseline neurological deficits, and to be obese (BMI ≥ 30). 94.9% of patients with steroid dependence experienced ≥ 1 SASE (vs. 34%) and 46.2% experienced ≥ 3 SASEs (vs. 3.8%). Mood symptoms (69.2% vs. 26.4%), hyperglycemia (53.8% vs. 7.5%) and infections (51.3% vs. 7.5%) were the most common SASEs. Median OS was inferior in steroid-dependent patients (18 vs 25 mo). Baseline obesity was identified as a risk factor for developing steroid dependence (OR 5.9). DISCUSSION SASEs are common in patients on prolonged steroids. Obesity may increase the risk of developing steroid dependence. Identifying patients at highest risk for steroid dependence may help guide future interventions to mitigate the negative effects of prolonged dexamethasone use.