Superficial vein thrombosis and recurrent venous thromboembolism: a pooled analysis of two observational studies.

Background: The management strategies for symptomatic isolated superficial vein thrombosis (SVT) (without concomitant deep vein thrombosis [DVT] or pulmonary embolism [PE]) have yet to achieve widespread consensus. Concerns have been raised regarding the usefulness of prescribing anticoagulant treatments to all patients with isolated SVT. Determining the isolated SVT subgroups who have the highest risks of venous thromboembolism (VTE) recurrence (composite of DVT, PE, and new SVT) may facilitate the identification of patients who are likely to benefit from anticoagulant treatment.
Design and Methods: We performed a pooled analysis on individual data from two observational, multicenter, prospective studies, to determine predictors for VTE recurrence and their impact in an unselected population of symptomatic isolated SVT patients.
Results: One thousand and seventy-four cases of symptomatic isolated SVT were followed up at 3 months. VTE recurrence was observed in 3.9% of the patients; 16.2% of the patients did not receive anticoagulants, and 0.6% experienced a VTE recurrence. Cancer, personal history of VTE and saphenofemoral/popliteal involvement significantly increased the risk of subsequent VTE or DVT/PE in univariate analyses. Only male sex significantly increased the risk of VTE or DVT/PE recurrence in multivariate analyses. Twelve percent of the patients had cancer or saphenofemoral junction involvement, and were at higher risk of DVT/PE recurrence than patients without those characteristics (4.7% vs. 1.9%, P= 0.06).
Conclusions: In patients with symptomatic SVT, only male sex significantly and independently increased the risk of VTE recurrence. Cancer or saphenofemoral junction involvement defined a population at high risk for deep VTE recurrence. Some SVTs might be safely managed without anticoagulants.
(© 2012 International Society on Thrombosis and Haemostasis.)