A Cochrane review [Abstract] 1 included 7 studies with a total of 40 846 subjects who were hospitalized for an acute medical illness with reduced mobility and/or elevated risk for venous thromboembolism (VTE). The studeis compared standard- versus extended-duration anticoagulation for primary thromboembolism prophylaxis. Different anticoagulants were used in the studies (enoxaparin, nadroparin, apixaban, betrixaban, rivaroxaban). Most studies reported short-term outcomes (during the treatment period and within 45 days of hospitalization).
The main results are shown in table T1. Extended-duration anticoagulation, compared with standard-duration anticoagulation, reduced the risk of short-term symptomatic VTE (number needed to benefit, NNTB 204, 95% CI 136 to 409), short-term total VTE (NNTB 107, 95% CI 76 to 178), and short-term composite of fatal and irreversible vascular events (NNTB 85, 95% CI 50 to 288), but these benefits were offset by an increased risk of short-term major bleeding (number needed to harm, NNTH 314, 95% CI 538 to 222). There was no difference in short-term all-cause mortality, short-term fatal bleeding, and in short-term VTE-related mortality (RR 0.78, 95% CI 0.58 to 1.05; 6 studies, n=36 170).
| Outcome | Relative effect (95% CI) | Anticipated absolute effects (95% CI) | Participants (studies) | |
|---|---|---|---|---|
| Standard-duration thromboprophylaxis | Extended-duration thromboprophylaxis | |||
| All-cause mortality | RR 0.97(0.87 to 1.08) | 34 per 1000 | 33 per 1000(30 to 37) | 38 080(5) |
| Symptomatic VTE* | RR 0.60(0.46 to 0.78)** | 12 per 1000 | 7 per 1000(6 to 10) | 24 773(4) |
| Total VTE* | RR 0.75(0.67 to 0.85) | 37 per 1000 | 28 per 1000(25 to 32) | 33 819(5) |
| Major bleeding | RR 2.05(1.51 to 2.79) | 3 per 1000 | 6 per 1000(5 to 8) | 40 374(7) |
| Fatal bleeding | RR 2.28(0.84 to 6.22) | 0 per 1000 | 0 per 1000(0 to 1) | 40 374(7) |
| Composite of fatal and irreversible vascular events | RR 0.71(0.56 to 0.91) | 41 per 1000 | 29 per 1000(23 to 37) | 7 513(1) |
| * venous thromboembolism, ** statistical heterogeneity I2 =65% | ||||
Clinical comments
NotePatients with high bleeding risk were excluded from all the studies. Date of latest search: References
Primary/Secondary Keywords
| ||||