Recurrent stroke: the role of thrombophilia in a large international pediatric stroke population

Risk factors for arterial ischaemic stroke in children include vasculopathy and prothrombotic risk factors but their relative importance to recurrent stroke is uncertain. Data on recurrent stroke from the databases held in Canada (Toronto), Germany (Kiel-Lubeck/Munster), and UK (London/Southampton) were pooled. Data were available from 894 patients aged 1 month to 18 years at first stroke (median age 6 years) with a median follow-up of 35 months. 160/894 patients (17.9%) had recurrence from 1 day to 136 months after first stroke (median 3.1 months). Among 288 children with vasculopathy, recurrence was significantly more common (hazard ratio (HR) 2.5, 95% confidence intervals (CI) 1.92-3.5) compared to children without vasculopathy. Adjusting for vasculopathy, isolated antithrombin deficiency (HR 3.9; 95%CI 1.4-10.9), isolated elevated lipoprotein (a) (HR 2.3; 95%CI 1.3-4.1), and the presence of more than one prothrombotic risk (HR 1.9; 95%CI 1.12-3.2) were independently associated with an increased risk of recurrence. Recurrence rates calculated per 100 person-years were 10 (95%CI 3-24) for antithrombin deficiency, 6 (95%CI 4-9) for elevated lipoprotein (a), and 13 (95%CI 7-20) for the presence of more than one prothrombotic risk. Identifying children at increased for second stroke events is important in intensifying measures aimed at preventing recurrent stroke