Risk categories for recurrent VTE and recommendations for the duration of therapy
| Risk group . | Patient characteristics associated with thrombotic event . | Risk of recurrence . | Duration of anticoagulant therapy . |
|---|---|---|---|
| Low | Reversible major risk factor (major surgery, pelvic or leg trauma, major medical illness) | < 5%/y | 3 mo |
| Moderate | Weak risk factor (estrogen use, long distance travel, minor trauma) and no inherited or acquired thrombophilia identified | < 10%/y | 6 mo |
| High | Unprovoked thrombotic event with no inherited or acquired thrombophilia identified | ∼ 10%/y | 6 mo* |
| Unprovoked thrombotic event with heterozygous factor V Leiden or prothrombin G20210A mutation | |||
| Very high | Recurrent unprovoked events with or without thrombophilic state identified | > 12%/y | Extended or indefinite |
| Unprovoked thrombotic event with antithrombin, protein C, or protein S deficiency; homozygous factor V Leiden; double heterozygosity; antiphospholipid antibody syndrome; advanced malignancy | therapy |
| Risk group . | Patient characteristics associated with thrombotic event . | Risk of recurrence . | Duration of anticoagulant therapy . |
|---|---|---|---|
| Low | Reversible major risk factor (major surgery, pelvic or leg trauma, major medical illness) | < 5%/y | 3 mo |
| Moderate | Weak risk factor (estrogen use, long distance travel, minor trauma) and no inherited or acquired thrombophilia identified | < 10%/y | 6 mo |
| High | Unprovoked thrombotic event with no inherited or acquired thrombophilia identified | ∼ 10%/y | 6 mo* |
| Unprovoked thrombotic event with heterozygous factor V Leiden or prothrombin G20210A mutation | |||
| Very high | Recurrent unprovoked events with or without thrombophilic state identified | > 12%/y | Extended or indefinite |
| Unprovoked thrombotic event with antithrombin, protein C, or protein S deficiency; homozygous factor V Leiden; double heterozygosity; antiphospholipid antibody syndrome; advanced malignancy | therapy |
May consider longer duration of therapy based on patient preference and should be reviewed annually.