Predicting the risk of recurrent venous thromboembolism (VTE).

To optimize patient outcomes with anticoagulation for venous thromboembolism (VTE), it is essential to assess patients for their recurrence risk. In this article, I will review the impact of clinical and laboratory risk factors for recurrent VTE. The presence or absence of VTE risk factors at the time of the index thrombotic event provides important information regarding recurrence risk. Patients with potent situational risk factors for thrombosis (e.g., surgery) are at low risk for recurrence while patients suffering unprovoked events are at high risk for recurrence. The presence of non-surgical clinical risk factors place patients at intermediate recurrence risk. Other clinical risk factors of variable recurrence potential include age, sex, cancer, pregnancy/puerperium, hormonal therapy and obesity. Laboratory risk factors for recurrence include thrombophilia, D dimer and other global coagulation assays as well as residual venous obstruction. Several multivariate VTE risk assessment models have been developed that combine clinical and laboratory risk factors of recurrence. If validated, these risk scores may allow for personalized anticoagulation therapy tailored to patients' individual recurrence risk.