Lymphoma and venous thromboembolism: influence on mortality

Background: The population-based incidence of acute venous thromboembolism (VTE) in adult patients diagnosed with non-Hodgkin's lymphoma has not been established, and the effect of VTE on survival is not clear. Aim: To determine the incidence of acute VTE in California residents diagnosed with lymphoma, and to determine the effect of acute VTE on survival. Methods: We used the California Cancer Registry coupled with the California Patient Discharge database to identify incident cases with lymphoma, 1991-1997, and the incidence of first-time VTE in these patients. Multivariable models were constructed to evaluate risk of developing acute VTE within 2 years, and a proportional hazard model was used to predict death within 2 years, using acute VTE as a time-dependent covariate. Results: There were 16,755 patients diagnosed with non-Hodgkin's lymphoma; 29% had low-grade, 66% intermediate/aggressive grade and 5.6% had high-grade lymphoma. Acute VTE developed in 3.6% of the patients by year 1 and 4.0% by the end of year 2. Significant predictors of acute VTE included advanced stage lymphoma, number of chronic comorbidities and advancing age. Significant predictors of death within 2 years included diagnosis of acute VTE, advanced stage disease, increasing number of co-morbidities, age over 75 years and intermediate or high grade histopathology. The effect of acute VTE on death increased as the time between lymphoma diagnosis and VTE diagnosis increased (HR= 1.7 95% CI: 1.5-1.9 for VTEs < 6 months; HR= 6.5 95% CI: 4.7-8.9 VTEs 12-24 months). Conclusions: Acute VTE developed frequently in patients with lymphoma, and VTE was a strong predictor of decreased survival. (C) 2014 Elsevier Ltd. All rights reserved.