Risk factors associated with recurrent venous thromboembolism after a first cerebral venous thrombosis event: A cohort study

Background: Cerebral venous thrombosis (CVT), although rare, is potentially fatal. Few studies have investigated risk factors associated with recurrent venous thromboembolism (VTE) after a first CVT event of which most are from Caucasian populations. The aim of this study was to evaluate risk factors associated with recurrent VTE after a first CVT event in a South American-population.

Patients/methods: In this cohort, multicenter study, patients aged >18 years and objectively-diagnosed with CVT were included, with follow-up starting after discontinuing anticoagulant therapy. The primary outcome was symptomatic VTE recurrence at any venous site.

Results: We included 203 patients with a median age of 30.8 (interquartile range [IQR], 24.7-40.9) years and a follow-up of 3.0 (IQR, 1.2-5.6) years. Most patients (86.2%) were women, and among those of reproductive age (n = 162), 65.4% developed CVT during oral contraceptive use, and 9.2% during pregnancy/puerperium. Thirteen patients (6.9%) developed VTE recurrence after a first CVT, yielding an overall rate of 1.6/100 patient-years (95% confidence interval [CI], 0.8-2.8). Recurrence rate was higher in males (4.6/100 patient-years; 95% CI, 1.2-11.7) than in females (1.2/100 patient-years; 95% CI, 0.6-2.4), and in patients with factor V Leiden mutation (9.2/100 patient-years; 95% CI, 1.1-33.1) than in those without it (1.2/100 patient-years; 95% CI, 0.5-2.4).

Conclusions: VTE recurrence after a first CVT was low. In spite of the limitation of small sample size, male sex and factor V Leiden mutation were the only factors associated with a significant higher risk of recurrent VTE after a first CVT in a multivariate analysis.