Introduction: Childhood arterial ischemic stroke (CAIS) affects 1.6 per 100,000/year and recurs in up to 20% at 5 years. Arteriopathies are common, predict recurrence, and affect the carotid (anterior) and vertebrobasilar (posterior) circulations differently. Differences in recurrence between anterior and posterior circulation CAIS have not been evaluated.
Hypothesis: Recurrence is higher for stroke involving the posterior circulation (PCAIS) than anterior circulation (ACAIS).
Methods: We analyzed 107 CAIS cases (61 isolated ACAIS, 46 isolated PCAIS) from a single-center prospective consecutive cohort from 1/1/06-1/1/15, with median age 7.7 years (IQR=3.1-13.6) and 70% male. Incidence of recurrent stroke was assessed with Kaplan-Meier survival estimates. Cox proportional hazards models compared recurrence risk between PCAIS and ACAIS.
Results: Median follow-up was 20.9 months (IQR 8.7-40.4). Recurrent stroke occurred in 9/46 PCAIS cases (19.6%; 8 males; 2 with multiple recurrences) and in 2/61 ACAIS cases (3.3%; 2 males). All PCAIS cases with recurrence were receiving antithrombotic therapy (aspirin or anticoagulant). Stroke risk factors in PCAIS with recurrence were: cervical dissection (4), sickle cell anemia (1), cardiac disease (2), multiple factors (2), thrombophilia (1), and unknown (1). For ACAIS, recurrence-free survival at 1 month, was 100%, and at 1 and 5 years was 96% (95% CI 85-99%). For PCAIS, recurrence-free survival at 1 month, 1 year, and 5 years was 88% (95% CI 75-95%), 81% (95% CI 66-90%), and 74% (95% CI 52-87%) [Figure]. The hazard ratio for recurrence in PCAIS compared to ACAIS was 6.4 (95% CI 1.4-29.8, p=0.017) in univariable analysis and 6.8 (95% CI 1.3-35.7, p=0.023) adjusting for sex, cardiac cause, and dissection.
Conclusions: At 5 years, 26% of children with PCAIS in our cohort had recurrent stroke compared to only 4% of children with ACAIS. Children with PCAIS may benefit from closer monitoring and additional prevention strategies.