Characteristics of included studies
| Author, year . | Characteristics of primary VTE event . | Treatment by arm∗ (n patients) . | Mean age (y) (SD) . | Percentage females . | Outcome assessment at end of treatment† . | Outcome assessment at end of follow-up† . |
|---|---|---|---|---|---|---|
| Primary treatment | ||||||
| Schulman et al, 198520 | First VTE episode: 0% (2nd DVT only) DVT: 100% proximal DVT Unprovoked: 0% | Short: 6 mo (n = 10) | 63.7 | 60 | NA | 15-27 mo |
| Long: 12 mo (n = 10) | 65.5 | 60 | ||||
| Siragusa et al, 200821 | First VTE episode: 100% DVT: 100% proximal DVT Unprovoked: 77% Included patients with RVT only | Short: 3 mo (n = 92) | 61.1 (11.5) | 48 | NA | 21 mo |
| Long: 12 mo (n = 88) | 57.1 (14.1) | 47 | ||||
| Agnelli et al, 200322 | First VTE episode: 100% DVT: 0% (PE only) Unprovoked: 56% | Short: 6 mo (n = 161) | 61 (15.5) | 58 | NA | 36 mo |
| Long: 12 mo (n = 165) | 62.9 (16.3) | 61 | ||||
| Agnelli et al, 200123 | First VTE episode: 100% DVT: 100% proximal DVT Unprovoked: 100% | Short: 3 mo (n = 133) | 67.7 (7.3) | 38 | NA | 36 mo |
| Long: 12 mo (n = 134) | 66.8 (6.7) | 46 | ||||
| Vitovec et al, 200924 | First VTE episode: 100% DVT: 100% Unprovoked: 100% | Short: 6 mo (n = 25) | Overall: 58 (12) | Overall: 54 | NA | 18 mo |
| Long: 12 mo (n = 27) | ||||||
| Van Gogh Investigators, 200725 | First VTE episode: 82% DVT: 55% Unprovoked: 60% | Short: 6 mo (n = 621) | 59.9 (15.4) | 48 | NA | 12 mo |
| Long: 12 mo (n = 594) | 60.2 (15.2) | 47 | ||||
| Both primary treatment and secondary prevention | ||||||
| Farraj, 200426 | First VTE episode: 100% DVT: 72% Unprovoked: 100% | Short (discontinued): 6 mo (n = 32) | 42 (14) | 44 | 24 mo | 36 mo |
| Long (indefinite): 24 mo (n = 32) | 41 (15) | 38 | ||||
| Couturaud et al, 201527 | First VTE episode: 100% DVT: 0% (PE only) Unprovoked: 100% | Short (discontinued): 6 mo (n = 187) | 57.3 (17.4) | 45 | 18 mo | 42 mo |
| Long (indefinite): 24 mo (n = 184) | 58.7 (17.9) | 58 | ||||
| Couturaud et al, 201928 | First VTE episode: 100% DVT: 100% proximal DVT Unprovoked: 100% | Short (discontinued): 6 mo (n = 54) | 61.5 (14.5) | 38 | 18 mo | 42 mo |
| Long (indefinite): 24 mo (n = 50) | 59 (17.2) | 28 | ||||
| Eischer et al, 200929 | First VTE episode: 100% DVT: 59% Unprovoked: NR Limited to patients with high factor VIII only | Short (discontinued): 6 mo (n = 17) | 54 (16) | 65 | 24 mo | 48 mo |
| Long (indefinite): 30 mo (n = 17) | 53 (18) | 71 | ||||
| Secondary prevention | ||||||
| Belcaro et al, 199330 | First VTE episode: 100% DVT: 100% Unprovoked: NR | Discontinued: 6 mo (n = 63) | 45.7 (12) | 52 | 30 mo | NA |
| Indefinite: 36 mo (n = 60) | 45.3 (11) | 52 | ||||
| Schulman et al, 200331 | First VTE episode: 86% DVT: 65% Unprovoked: NR | Discontinued: 6 mo (n = 611) | 58 (15) | 49 | 18 mo | NA |
| Indefinite: 24 mo (n = 612) | 56 (15) | 46 | ||||
| Agnelli et al, 201332 | First VTE episode: 100% DVT: 65% Unprovoked: 92% | Discontinued: 6-12 mo (n = 829) | 57.1 (15.2) | 35 | 12 mo | NA |
| Indefinite: Finished 6-12 mo, then continued 12 mo (n = 1653) | 56.6 (15.3) to 56.4 (15.6) | 42 to 42 | ||||
| Palareti et al, 200633 | First VTE episode: 100% DVT: 63% Unprovoked: 100% | Discontinued: 3 mo (n = 120) | 68.2 (12.5) | 58 | 18 mo | NA |
| Indefinite: 21 mo (n = 103) | 70.1 (13.7) | 47 | ||||
| Ridker et al, 200334 | First VTE episode: 62% DVT: NR Unprovoked: 100% | Discontinued: 6.5 mo median (n = 253) | 53 (47-64) median | 47 | Mean of 2.1 y and up to 4.3 y, the trial was terminated prematurely | NA |
| Indefinite: Finished 6.5 mo median, followed by mean of 2.1 y and up to 4.3 y (n = 255) | 53 (46-65) median | 47 | ||||
| Kearon et al, 199935 | First VTE episode: 100% DVT: 75% Unprovoked: 100% | Discontinued: 3 mo (n = 83) | 58 (16) | 47 | 24 mo | NA |
| Indefinite: 27 mo (n = 79) | 59 (16) | 32 | ||||
| Bauersachs et al, 201036 | First VTE episode: 100% DVT: 62% Unprovoked: 74% | Discontinued: 6-12 mo (n = 594) | 58 (16) | 43 | 12 mo | NA |
| Indefinite: Finished 6-12 mo, then continued 6 or 12 mo (n = 602) | 58 (16) | 41 | ||||
| Schulman et al, 199737 | First VTE episode: 0% (2nd VTE only) DVT: 85% Unprovoked: NR | Discontinued: 6 mo (n = 111) | 65 (12.4) | 37 | 48 mo | NA |
| Indefinite: 48 mo (n = 116) | 64 (12.5) | 41 | ||||
| Schulman et al, 201338 | First VTE episode: NR DVT: 65% Unprovoked: NR | Discontinued: 6-18 mo, mean of 10 mo (n = 681) | 56.1 (15.5) | 44 | 6 mo | NA |
| Indefinite: Finished 6-18 mo, then continued 6 mo (n = 662) | 55.5 (15.1) | 45 | ||||
| Becattini et al, 201239 | First VTE episode: 100% DVT: 63% Unprovoked: 100% | Discontinued: 6-18 mo (n = 197) | 62.1 (15.1) | 38 | 24 mo | NA |
| Indefinite: Finished 6-18 mo, then continued 24 mo (n = 205) aspirin | 61.9 (15.3) | 34 | ||||
| Brighton et al, 201240 | First VTE episode: 100% DVT: 57% Unprovoked: 100% | Discontinued: 89% of 3-12 mo (n = 411) | 54 (15.8) | 46 | The median duration of follow-up was 37.2 mo | NA |
| Indefinite: Finished 1.5-24 mo, then continued 24-48 mo (n = 411) aspirin | 55 (16.0) | 45 | ||||
| Bradbury et al, 202041 | First VTE episode: 100% DVT: 51% Unprovoked: 100% | Discontinued: 3 mo (n = 140) | 63.3 (12.7) | 33 | 24 mo | NA |
| Indefinite: 27 mo (n = 141) | 62.2 (13) | 32 | ||||
| Author, year . | Characteristics of primary VTE event . | Treatment by arm∗ (n patients) . | Mean age (y) (SD) . | Percentage females . | Outcome assessment at end of treatment† . | Outcome assessment at end of follow-up† . |
|---|---|---|---|---|---|---|
| Primary treatment | ||||||
| Schulman et al, 198520 | First VTE episode: 0% (2nd DVT only) DVT: 100% proximal DVT Unprovoked: 0% | Short: 6 mo (n = 10) | 63.7 | 60 | NA | 15-27 mo |
| Long: 12 mo (n = 10) | 65.5 | 60 | ||||
| Siragusa et al, 200821 | First VTE episode: 100% DVT: 100% proximal DVT Unprovoked: 77% Included patients with RVT only | Short: 3 mo (n = 92) | 61.1 (11.5) | 48 | NA | 21 mo |
| Long: 12 mo (n = 88) | 57.1 (14.1) | 47 | ||||
| Agnelli et al, 200322 | First VTE episode: 100% DVT: 0% (PE only) Unprovoked: 56% | Short: 6 mo (n = 161) | 61 (15.5) | 58 | NA | 36 mo |
| Long: 12 mo (n = 165) | 62.9 (16.3) | 61 | ||||
| Agnelli et al, 200123 | First VTE episode: 100% DVT: 100% proximal DVT Unprovoked: 100% | Short: 3 mo (n = 133) | 67.7 (7.3) | 38 | NA | 36 mo |
| Long: 12 mo (n = 134) | 66.8 (6.7) | 46 | ||||
| Vitovec et al, 200924 | First VTE episode: 100% DVT: 100% Unprovoked: 100% | Short: 6 mo (n = 25) | Overall: 58 (12) | Overall: 54 | NA | 18 mo |
| Long: 12 mo (n = 27) | ||||||
| Van Gogh Investigators, 200725 | First VTE episode: 82% DVT: 55% Unprovoked: 60% | Short: 6 mo (n = 621) | 59.9 (15.4) | 48 | NA | 12 mo |
| Long: 12 mo (n = 594) | 60.2 (15.2) | 47 | ||||
| Both primary treatment and secondary prevention | ||||||
| Farraj, 200426 | First VTE episode: 100% DVT: 72% Unprovoked: 100% | Short (discontinued): 6 mo (n = 32) | 42 (14) | 44 | 24 mo | 36 mo |
| Long (indefinite): 24 mo (n = 32) | 41 (15) | 38 | ||||
| Couturaud et al, 201527 | First VTE episode: 100% DVT: 0% (PE only) Unprovoked: 100% | Short (discontinued): 6 mo (n = 187) | 57.3 (17.4) | 45 | 18 mo | 42 mo |
| Long (indefinite): 24 mo (n = 184) | 58.7 (17.9) | 58 | ||||
| Couturaud et al, 201928 | First VTE episode: 100% DVT: 100% proximal DVT Unprovoked: 100% | Short (discontinued): 6 mo (n = 54) | 61.5 (14.5) | 38 | 18 mo | 42 mo |
| Long (indefinite): 24 mo (n = 50) | 59 (17.2) | 28 | ||||
| Eischer et al, 200929 | First VTE episode: 100% DVT: 59% Unprovoked: NR Limited to patients with high factor VIII only | Short (discontinued): 6 mo (n = 17) | 54 (16) | 65 | 24 mo | 48 mo |
| Long (indefinite): 30 mo (n = 17) | 53 (18) | 71 | ||||
| Secondary prevention | ||||||
| Belcaro et al, 199330 | First VTE episode: 100% DVT: 100% Unprovoked: NR | Discontinued: 6 mo (n = 63) | 45.7 (12) | 52 | 30 mo | NA |
| Indefinite: 36 mo (n = 60) | 45.3 (11) | 52 | ||||
| Schulman et al, 200331 | First VTE episode: 86% DVT: 65% Unprovoked: NR | Discontinued: 6 mo (n = 611) | 58 (15) | 49 | 18 mo | NA |
| Indefinite: 24 mo (n = 612) | 56 (15) | 46 | ||||
| Agnelli et al, 201332 | First VTE episode: 100% DVT: 65% Unprovoked: 92% | Discontinued: 6-12 mo (n = 829) | 57.1 (15.2) | 35 | 12 mo | NA |
| Indefinite: Finished 6-12 mo, then continued 12 mo (n = 1653) | 56.6 (15.3) to 56.4 (15.6) | 42 to 42 | ||||
| Palareti et al, 200633 | First VTE episode: 100% DVT: 63% Unprovoked: 100% | Discontinued: 3 mo (n = 120) | 68.2 (12.5) | 58 | 18 mo | NA |
| Indefinite: 21 mo (n = 103) | 70.1 (13.7) | 47 | ||||
| Ridker et al, 200334 | First VTE episode: 62% DVT: NR Unprovoked: 100% | Discontinued: 6.5 mo median (n = 253) | 53 (47-64) median | 47 | Mean of 2.1 y and up to 4.3 y, the trial was terminated prematurely | NA |
| Indefinite: Finished 6.5 mo median, followed by mean of 2.1 y and up to 4.3 y (n = 255) | 53 (46-65) median | 47 | ||||
| Kearon et al, 199935 | First VTE episode: 100% DVT: 75% Unprovoked: 100% | Discontinued: 3 mo (n = 83) | 58 (16) | 47 | 24 mo | NA |
| Indefinite: 27 mo (n = 79) | 59 (16) | 32 | ||||
| Bauersachs et al, 201036 | First VTE episode: 100% DVT: 62% Unprovoked: 74% | Discontinued: 6-12 mo (n = 594) | 58 (16) | 43 | 12 mo | NA |
| Indefinite: Finished 6-12 mo, then continued 6 or 12 mo (n = 602) | 58 (16) | 41 | ||||
| Schulman et al, 199737 | First VTE episode: 0% (2nd VTE only) DVT: 85% Unprovoked: NR | Discontinued: 6 mo (n = 111) | 65 (12.4) | 37 | 48 mo | NA |
| Indefinite: 48 mo (n = 116) | 64 (12.5) | 41 | ||||
| Schulman et al, 201338 | First VTE episode: NR DVT: 65% Unprovoked: NR | Discontinued: 6-18 mo, mean of 10 mo (n = 681) | 56.1 (15.5) | 44 | 6 mo | NA |
| Indefinite: Finished 6-18 mo, then continued 6 mo (n = 662) | 55.5 (15.1) | 45 | ||||
| Becattini et al, 201239 | First VTE episode: 100% DVT: 63% Unprovoked: 100% | Discontinued: 6-18 mo (n = 197) | 62.1 (15.1) | 38 | 24 mo | NA |
| Indefinite: Finished 6-18 mo, then continued 24 mo (n = 205) aspirin | 61.9 (15.3) | 34 | ||||
| Brighton et al, 201240 | First VTE episode: 100% DVT: 57% Unprovoked: 100% | Discontinued: 89% of 3-12 mo (n = 411) | 54 (15.8) | 46 | The median duration of follow-up was 37.2 mo | NA |
| Indefinite: Finished 1.5-24 mo, then continued 24-48 mo (n = 411) aspirin | 55 (16.0) | 45 | ||||
| Bradbury et al, 202041 | First VTE episode: 100% DVT: 51% Unprovoked: 100% | Discontinued: 3 mo (n = 140) | 63.3 (12.7) | 33 | 24 mo | NA |
| Indefinite: 27 mo (n = 141) | 62.2 (13) | 32 | ||||
NA, not assessed; NR, not reported; RVT, residual vein thrombosis.
Treatment duration includes the period that patients were on an anticoagulant or antithrombotic therapy (including the period before randomization). Short or long arms refer to studies that assessed primary treatment; these studies assessed outcomes at least 3 months after treatment was stopped in the long arm. Discontinued or indefinite arms refer to studies that assessed secondary prevention; these studies assessed outcomes immediately after treatment was stopped in the indefinite arm. Four studies assessed both primary treatment and secondary prevention and reported outcomes at 2 time points as noted in the table.
The time period was counted from randomization.