Predictors of Venous Thromboembolism in Patients with Glioblastoma.

To evaluate different risk factors associated with development of venous thromboembolism (VTE) in patients with Glioblastoma (GBM). A retrospective chart review was performed to include patients diagnosed with GBM from 2001 to 2011. Cases (n = 162) were defined as patients with GBM who developed VTE after diagnosis of GBM. Controls (n = 840) were defined as patients with GBM with no history of VTE. Data was collected for multiple variables including age, gender, race, length of hospital stay after brain biopsy, total number of hospital admissions unrelated to VTE, Karnofsky Performance Status (KPS), use of Bevacizumab and any bleeding episodes. Patients with GBM who had VTE had poorer KPS scores, with the majority (57%) being in between 40 and 70, as compared to the controls where majority (82%) had better performance (KPS 80-100). For every one year increase in age, the odds of developing VTE increased by 3% (OR 1.03, 95%CI 1.02-1.04, p < 0.001) with the mean age being 61.8 ± 11.4 years. GBM patients who developed a VTE were found to have greater number of hospital admissions (OR 1.43, 95%CI 1.33-1.53, p < 0.001) and longer stays in hospital after GBM biopsy (OR 1.14, 95%CI 1.09-1.18, p < 0.001). Patients receiving Bevacizumab were more likely to develop VTE (OR 1.79, 95%CI 1.21-2.64, p < 0.001) and were more likely to have a bleed (OR 3.78, 95% CI 2.70-5.30, p < 0.001). Patients with GBM are at a higher risk of developing VTE. The risk is higher in older patients who require multiple hospital admissions, longer duration of hospital stays related to GBM biopsy, and in patients with lower KPS scores. Bevacizumab use is related to a higher incidence of VTE as well as bleeds. This study suggests that a more aggressive strategy for VTE prophylaxis should be considered in GBM patients with risk factors for VTE.