The incidence of early recurrent venous thromboembolism: a systematic review and meta-analysis

Background: Patients with venous thromboembolism (VTE) receive anticoagulation for at least 3 months. To evaluate recurrence risk thereafter, some strategies include D-dimer testing after discontinuing anticoagulation, which raises concern about early recurrence. Objectives: To assess the incidence of recurrent VTE within 30 days after stopping anticoagulation. Methods: We conducted a systematic review of EMBASE, CENTRAL, and MEDLINE to identify controlled trials and cohort studies of adult noncancer patients with deep vein thrombosis of the leg and/or pulmonary embolism treated with anticoagulants for ≥3 months. The primary outcome was symptomatic VTE within 30 days. The risk of bias was assessed using a modified version of the Newcastle-Ottawa Scale. Pooled recurrence rates were calculated using fixed random-effects meta-analyses. Results: Of 42 studies, 24 (57%) provided data, encompassing 11,407 patients. Early recurrence occurred in 115 patients (1.01%), with a pooled incidence of 1.04% (95% CI, 0.8%-1.4%). Men had a risk similar to that of women (risk ratio, 1.2; 95% CI, 0.6-2.3; P = .7). Unprovoked VTE was associated with a 2.6-fold increase in risk (95% CI, 1.4-4.6; P < .001) compared with provoked VTE. Patients with deep vein thrombosis at presentation had a similar risk of recurrence compared with those with an incident pulmonary embolism (risk ratio, 0.6; 95% CI: 0.3-1.2; P = .1). Findings regarding age were inconsistent. None of the recurrences was fatal. The overall risk of bias was low. Conclusion: The incidence of early VTE recurrence after stopping anticoagulation is low. Temporarily discontinuing therapy to assess recurrence risk, therefore, appears safe and may aid in guiding treatment duration.