on September 24, 2009
Published online before print September 24, 2009, doi: 10.1161/ATVBAHA.109.190827
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Submitted on May 11, 2009
Accepted on September 15, 2009
High Factor VIII Levels Independently Predict Venous Thromboembolism in Cancer Patients. The Cancer and Thrombosis Study
R. Vormittag ;
From the Clinical Division of Hematology and Hemostaseology, Department of Medicine I (R.V., R.S., C.A., I.P.), the Clinical Division of Oncology, Department of Medicine I (C.M., C.Z.), the Department of Medical and Chemical Laboratory Diagnostics (P.Q.), and the Core Unit for Medical Statistics and Informatics (D.D.), Medical University of Vienna, Austria.
* To whom correspondence should be addressed. E-mail: ingrid.pabinger{at}meduniwien.ac.at.
Objective—Patients with cancer are at an increased risk for venous thromboembolism (VTE). Clotting factor VIII activity (FVIII) has been established as risk factor of primary and recurrent VTE. We investigated FVIII as predictive parameter of VTE in cancer patients.
Methods and Results—The prospective observational Cancer and Thrombosis Study includes patients with newly diagnosed cancer or disease progression, study end point is symptomatic VTE. FVIII was measured on a Sysmex CA 7000 analyzer. Data on 840 patients (median age: 62 years, 25th to 75th percentile 53 to 68, 378 women) were available for analyses, of these 111 patients had hematologic malignancies and 729 solid cancer. During a median observation time of 495 days 62 events occurred. Cumulative probability of VTE after 6 months was 14% in patients with elevated FVIII-levels and 4% in those with normal levels (P=0.001). The association was strongest in younger patients: whereas in 40-year-old patients a 2-fold VTE risk per factor VIII increase of 20% was observed (HR=2.0 [95% CI: 1.5 to 2.7], P<0.0001), this association was still present but attenuated in older patients.
Conclusions—FVIII is independently associated with an increased risk of VTE in cancer patients. The association between FVIII and VTE risk declines with increasing age.
Key words: cancer • factor VIII • prospective study • thrombosis • venous thromboembolism