A risk score for prediction of recurrence in patients with unprovoked venous thromboembolism (DAMOVES)

Abstract

Background: In patients with unprovoked venous thromboembolism (VTE), the optimal duration of anticoagulation is anchored on estimating the risk of disease recurrence. We aimed to develop a simple risk assessment model that improves prediction of the recurrence risk.

Methods: In a prospective cohort study, 398 patients with a first unprovoked VTE were followed up for a median of 21.3months after discontinuation of anticoagulation. We excluded patients with a strong thrombophilic defect. Preselected clinical and laboratory variables were analyzed based on the independent confirmation of the impact on the recurrence risk, simplicity of assessment, and reproducibility. Multivariable Cox regression analysis was used to develop a recurrence score that was subsequently internally validated by bootstrap analysis.

Results: A total of 65 patients (16.3%) had recurrent VTE. In all patients, VTE recurred spontaneously. Male sex (HR=2.89 [95% CI 1.21-6.90] P=0.016), age (HR=1.0310 per additional decade [95% CI 1.01-1.07] P=0.011), obesity (HR=3.92 [95% CI 1.75-8.75] P=0.0001), varicose veins (HR=4.14 [95% CI 1.81-9.43] P=0.0001), abnormal D-dimer during anticoagulation (HR=13.66 [95% CI 4.74-39.37] P=0.0001), high factor VIII coagulant activity (HR=1.01 [95% CI 1.00-1.02] P=0.028) and heterozygous of factor V Leiden and/or Prothrombin G20210A mutation (HR=13.86 [95% CI 5.87-32.75] P=0.0001) were related to a higher recurrence risk. Using these variables, we developed a nomogram [hereafter referred to as DAMOVES score (D-dimer, Age, Mutation, Obesity, Varicose veins, Eight, Sex)] for prediction of recurrence in an individual patient.

Conclusions: The DAMOVES score can be used to predict recurrence risk in patients with a first unprovoked VTE and may be useful to decide whether anticoagulant therapy should be continued indefinitely or stopped after an initial treatment period of at least 3months.

Keywords: Anticoagulation; Recurrence; Risk; Risk assessment model; Venous thrombosis.