Association between hyperglycemia and survival in patients with newly diagnosed glioblastoma

Abstract

Purpose: Hyperglycemia has been associated with poor outcomes in many disease states. This retrospective study assessed the association between hyperglycemia and survival in patients with newly diagnosed glioblastoma multiforme (GBM). PATIENTS AND METHODS; Between 1999 and 2004, before the standard use of temozolomide, 191 patients were accrued onto New Approaches to Brain Tumor Therapy CNS Consortium trials with similar eligibility criteria. Time-weighted mean glucose and mean glucocorticoid dose were calculated for each patient using all values collected regularly in follow-up. The primary outcome was survival.

Results: Mean glucose levels ranged between 65 and 459 mg/dL. These were divided into quartiles: quartile one (< 94 mg/dL), quartile two (94 to 109 mg/dL), quartile three (110 to 137 mg/dL), and quartile four (> 137 mg/dL). Median survival times for patients in quartiles one, two, three, and four were 14.5, 11.6, 11.6, and 9.1 months, respectively. The association between higher mean glucose and shorter survival persisted after adjustment for mean daily glucocorticoid dose, age, and baseline Karnofsky performance score (KPS). Compared with patients in the lowest mean glucose quartile, those in quartile two (adjusted hazard ratio [HR], 1.29; 95% CI, 0.85 to 1.96), quartile three (adjusted HR, 1.35; 95% CI, 0.89 to 2.06), and quartile four (adjusted HR, 1.57; 95% CI, 1.02 to 2.40) were at progressively higher risk of dying (P = .041 for trend).

Conclusion: In these patients with newly diagnosed GBM and good baseline KPS, hyperglycemia was associated with shorter survival, after controlling for glucocorticoid dose and other confounders. The effect of intensive management of glucocorticoid-related hyperglycemia on survival deserves additional study in patients with GBM.

Fig 1.

Adjusted survival curves comparing quartiles of mean time-weighted glucose, constructed using multivariate Cox proportional hazards regression, and adjusting for mean daily dexamethasone dose, age, and Karnofsky performance score. The ranges of time-weighted mean glucose for quartiles one, two, three, and four were < 94, 94 to 109, 110 to 137, and > 137 mg/dL, respectively.