The quality of evidence is downgraded by indirectness (results are based on subgroup analyses), and by imprecise results (wide confidence intervals and few outcome events).
A Cochrane review [Abstract] 1 included 15 studies with a total of 1 615 subjects with cancer and venous thromboembolism (VTE). 13 studies (n=1 025) compared low molecular weight heparin (LMWH) with unfractionated heparin (UFH), one (n=477) compared fondaparinux with UFH and LMWH, and one (n=113) compared dalteparin with tinzaparin.
LMWH decreased statistically insignificantly mortality at 3 months compared to UFH (RR 0.66, 95% CI 0.40 to 1.10; 5 studies, n=418), and did not rule out a clinically significant increase or decrease in VTE recurrence (RR 0.69, 95% CI 0.27 to 1.76; 3 studies, n=422).There was no differences between fondaparinux and heparin (UFH or LMWH) for the outcomes of mortality at 3 months (RR 1.25, 95% CI 0.86 to 1.81; 1 study, n=477), recurrent VTE (RR 0.93, 95% CI 0.56 to 1.54; 1 study, n=477), major bleeding (RR 0.82, 95% CI 0.40 to 1.66; 1 study, n=477), or minor bleeding (RR 1.53, 95% CI 0.88 to 2.66; 1 study, n=477).The study comparing dalteparin with tinzaparin did not find differences in mortality (RR 0.86, 95% CI 0.43 to 1.73; 1 study, n=113), recurrent VTE (RR 0.44, 95% CI 0.09 to 2.16; 1 study, n=113), major bleeding (RR 2.19, 95% CI 0.20 to 23.42; 1 study, n=113), or minor bleeding (RR 0.82, 95% CI 0.30 to 2.21; 1 study, n=113).
Primary/Secondary Keywords