Frequency, risk factors, and trends for venous thromboembolism among hospitalized cancer patients

Abstract

Background: Venous thromboembolism (VTE) contributes to morbidity and mortality in cancer patients and is a frequent complication of anticancer therapy. In the current study, the frequency, risk factors, and trends associated with VTE were examined among hospitalized cancer patients.

Methods: A retrospective cohort study was conducted using the discharge database of the University HealthSystem Consortium. This included 1,824,316 hospitalizations between 1995 and 2003 at 133 U.S. medical centers.

Results: Among 1,015,598 cancer patients, 34,357 (3.4%) were diagnosed with deep venous thrombosis and 11,515 with pulmonary embolism (PE) (1.1%) for an overall VTE rate of 4.1%. Subgroups of cancer patients with the highest rates included black ethnicity (5.1% per hospitalization) and those receiving chemotherapy (4.9%). Sites of cancer with the highest rates of VTE included pancreas (8.1%), kidney (5.6%), ovary (5.6%), lung (5.1%), and stomach (4.9%). Among hematologic malignancies, myeloma (5%), non-Hodgkin lymphoma (4.8%), and Hodgkin disease (4.6%) had the highest rates of VTE. The rate of VTE increased by 28%, secondary to a near-doubling of PE rates from 0.8% to 1.5% (P < .0001). Among patients receiving chemotherapy, the rates of VTE rose from 3.9% to 5.7%, an increase of 47% (P < .0001). In multivariate analysis, risk factors associated with VTE included age >or=65 years, female sex, black ethnicity, use of chemotherapy, primary site of cancer, presence of comorbidities, and year of admission.

Conclusions: VTE, particularly PE, is an increasingly frequent complication of hospitalization in cancer patients. Patients with black ethnicity, specific sites of cancer, or those receiving chemotherapy are disproportionately at risk.