Impact of Dexamethasone on Metabolic Profile and Survival in Glioblastoma

Abstract

Background: Although patients with glioblastoma require corticosteroids, such as dexamethasone, for symptom control, they could worsen prognosis. However, it is not clear whether personalized corticosteroid doses have this effect. We have examined the effects of different doses of dexamethasone on the metabolic profile and prognosis of patients with glioblastoma. Methods: Patients diagnosed with glioblastoma from 2013 to 2016 were included. We recorded changes in glycemia, glycosylated hemoglobin, insulin, Insulin-like Growth Factor 1 (IGF1), triglycerides, and total cholesterol and correlated these changes with dexamethasone dose, Progression-Free Survival (PFS), and Overall Survival (OS). Results: Among the 32 evaluable patients, the median daily dose of dexamethasone during radiotherapy and concomitant temozolomide was 1.4 mg/day (range=0, 8.3 mg/day). The median cumulative dose of dexamethasone was 250 mg (range=0 to 2,648 mg). Neither dexamethasone during concomitant therapy nor median cumulative dose >250 mg was associated with PFS or OS. Total cholesterol increase at progression relative to baseline levels (+20.5 mg/dL, p=0.04) was associated with cumulative dexamethasone dose >250 mg (p=0.01). Only hyperglycemia was identified as an independent marker of shorter PFS (HR, 3.7; 95% CI=1.3, 10.8; p=0.02) and OS (HR, 8.4; 95% CI=2.6, 27.1; p<0.001). Conclusion: Personalized doses of dexamethasone are not associated with worse outcome. The interrelation between dexamethasone, cholesterol, and outcome merits further investigation