Risk factors for recurrence in deep vein thrombosis patients following a tailored anticoagulant treatment incorporating residual vein obstruction

Background: Finding the optimal duration of anticoagulant treatment following an acute event of deep vein thrombosis (DVT) is challenging. Residual venous obstruction (RVO) has been identified as a risk factor for recurrence, but data on management strategies incorporating the presence of RVO and associated recurrence rates in defined clinical care pathways (CCP) are lacking. Objectives: We aimed to investigate the long-term clinical outcomes and predictors of venous thromboembolism (VTE) recurrence in a contemporary cohort of patients with proximal DVT and managed in a CCP incorporating the presence of RVO. Patients: All patients treated at the Maastricht University Medical Center within an established clinical care pathway from June 2003 through June 2013 were prospectively followed for up to 11 years in a prospective management study. Results: Of 479 patients diagnosed with proximal DVT, 474 completed the two-year CCP (99%), and 457 (94.7%) the extended follow-up (2231.2 patient-years; median follow-up 4.6 years). Overall VTE recurrence was 2.9 per 100 patient-years, 1.3 if provoked by surgery, 2.1 if a non-surgical transient risk factor was present and 4.0 if unprovoked. Predictors of recurrent events were unprovoked VTE (adjusted hazard ratio [HR] 4.6; 95% CI 1.7, 11.9), elevated D-dimer one month after treatment was stopped (HR 3.3; 1.8, 6.1), male sex (HR 2.8; 1.5, 5.1), high factor VIII (HR 2.2; 1.2, 4.0) and use of contraceptives (HR 0.1; 0.0, 0.9). Conclusions: Patients with DVT managed within an established clinical care pathway incorporating the presence of RVO had relatively low incidences of VTE recurrence.