Cancer patients receiving anticoagulants for venous thromboembolism have an elevated bleeding risk.
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This secondary analysis of CATCH assessed characteristics of clinically relevant bleeding (CRB).
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CRB occurs in 15% of cancer patients with thrombosis using therapeutic doses of anticoagulation.
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After multivariate analysis, risk factors for CRB were age >75 years and intracranial malignancy.
Summary: Background
Cancer patients with acute venous thromboembolism (VTE) receiving anticoagulant treatment have an increased bleeding risk.
Objectives
We performed a prespecified secondary analysis of the randomized, open‐label, Phase III CATCH trial (NCT01130025) to assess the rate and sites of and the risk factors for clinically relevant bleeding (CRB).
Patients/Methods
Patients with active cancer and acute, symptomatic VTE received either tinzaparin 175 IU kg−1 once daily or warfarin (target International Normalized Ratio [INR] of 2.0–3.0) for 6 months. Fisher's exact test was used to screen prespecified clinical risk factors; those identified as being significantly associated with an increased risk of CRB then underwent competing risk regression analysis of time to first CRB.
Results
Among 900 randomized patients, 138 (15.3%) had 180 CRB events. CRB occurred in 60 patients (81 events) in the tinzaparin group and in 78 patients (99 events) in the warfarin group (hazard ratio [HR] 0.64; 95% confidence interval [CI] 0.45–0.89). Common bleeding sites were gastrointestinal (36.7%; n = 66), genitourinary (22.8%; n = 41), and nasal (10.0%; n = 18). In multivariate analysis, the risk of CRB increased with age > 75 years (HR 1.83, 95% CI 1.14–2.94) and intracranial malignancy (HR 1.97, 95% CI 1.07–3.62). In the warfarin group, 40.4% of CRB events occurred in patients with with an INR of < 3.0. A lower time in therapeutic range was associated with a higher risk of CRB.
Conclusions
CRB is a frequent complication in cancer patients with VTE during anticoagulant treatment, and is associated with age > 75 years and intracranial malignancy.
