Real-World Analysis of Venous Thromboembolism Rates and Thromboprophylaxis Prescribing In US Patients with Cancer.

Deep-vein thrombosis (DVT) is a frequent complication of cancer and treatment of cancer. Among clinical guidelines, there is broad consensus regarding the importance of thromboprophylaxis in hospitalized cancer patients, including prolonged prophylaxis in high-risk patients. The objective of this analysis was to assess the real-world use of prophylaxis for DVT, as well as symptomatic rates of DVT and pulmonary embolism (PE) in cancer patients, both during hospitalization and after hospital discharge.

Data were extracted from the US Premier Perspective(tm)-i3 Pharma Informatics linked database for non-surgical cancer patients who were admitted to hospital from January 2005 to November 2007. Included patients were aged ≥ 18 years and had ≥ 6 months' continuous plan enrollment. Patients were excluded if they were discharged to an acute-care facility, had length of hospital stay ≤ 0 or > 30 days, had missing/unknown gender or age data, or if they were diagnosed with atrial fibrillation during index hospitalization. Clinical rates of DVT/PE, as well as thromboprophylaxis status and duration were evaluated for during hospitalization and post-discharge.

Of the 3,759 cancer patients analyzed, 51.9% received inpatient pharmacological and/or mechanical prophylaxis, and 2.8% received outpatient pharmacological prophylaxis in the 14 days following discharge. During index hospitalization 40.0% of patients received mechanical prophylaxis and 21.1% pharmacological prophylaxis, with 9.3% of patients receiving a combination of mechanical and pharmacological prophylaxis. Mean (± standard deviation) duration of prophylaxis was 1.3 (± 2.3) days for inpatients and 0.7 (± 4.5) days post-discharge among all cancer patients. Symptomatic DVT/PE occurred in 2.4% of patients during hospitalization. In the 30 days following hospital discharge, 1.7% of patients was either rehospitalized for DVT/PE or treated for DVT/PE in the outpatient setting.

This real-world analysis demonstrates considerable symptomatic rates of DVT/PE in hospitalized cancer patients, with approximately half of patients not receiving any thromboprophylaxis. The risk of DVT/PE persisted into the outpatient setting, but few patients received anticoagulants post-discharge. Further efforts are needed to ensure that patients with cancer receive appropriate thromboprophylaxis and that it is of adequate duration to reduce the large burden of DVT/PE.

Acknowledgment: This study was funded by sanofi-aventis U.S., Inc. The authors received editorial/writing support in the preparation of this abstract provided by Tessa Hartog, PhD of Excerpta Medica, funded by sanofi-aventis U.S., Inc.

Amin:sanofi-aventis US Inc.: Honoraria, Speakers Bureau. Lin:sanofi-aventis US Inc.: Employment, Research Funding. Thompson:sanofi-aventis US Inc.: Employment. Wiederkehr:sanofi-aventis US Inc.: Research Funding.