Three years after suffering a stroke, 19 percent of children with posterior circulation childhood arterial ischemic stroke (PCAIS)
 and 4 percent of children with anterior circulation CAIS (ACAIS) had a recurrent stroke, according to a retrospective analysis.

Lead researcher Michael Y. Uohara, BS, of The Children’s Hospital of Philadelphia and the University of Pennsylvania, and colleagues published their results online in JAMA Neurology on Jan. 23.

The researchers noted that CAIS affects 1.6 per 100,000 children per year and that PCAIS was less common than ACAIS.

This analysis included 107 patients with CAIS who presented to The Children’s Hospital of Philadelphia between 2006 and 2014. The median age of the children was 7.7 years old, and they each had confirmed CAIS that occurred between 29 days and 17.99 years old. In addition, 70.1 percent of the patients were boys, 67 percent were white and 57 percent had ACAIS.

Of the CAIS, 26.2 percent were classified as cervicoaortic arteriopathy, 22.4 percent as cardiogenic, 17.8 percent as unilateral focal cerebral arteriopathy, 15.9 percent as indeterminate, 8.4 percent as bilateral cerebral arteriopathy, 6.5 percent as small vessel disease, 1.9 percent as multifactorial and 0.9 percent as sickle cell disease without vasculopathy. Further, of the 99 patients receiving antithrombotic treatment, 56.6 percent received aspirin, 42.4 percent received anticoagulation and 1 percent received aspirin and anticoagulation.

The recurrence-free survival rates were 95 percent at one month and 10 percent at one and three years. Of the 11 patients who had recurrent AIS, 10 had a recurrence within the first six months and five had a recurrence within the first month.

Ten of the 11 recurrent strokes also occurred in boys, while nine occurred in patients with PCAIS and two occurred in patients with ACAIS. Further, 20.8 percent of children with cervical artery dissection and 26.3 percent of children with vertebrobasilar dissection had a recurrent stroke.

The recurrence-free survival rates after PCAIS were 88 percent at one month and 81 percent at one and three years, while the recurrence-free survival rates after ACAIS were 100 percent at one month and 96 percent at one and three years.

A univariable analysis found that the hazard ratio for recurrence after PCAIS compared with the hazard ratio after ACAIS was 6.4. When the researchers conducted a multivariable analysis including sex and cervical dissection, they found the hazard ratio for recurrence after PCAIS compared with that after ACAIS was 5.3.

The researchers cited a few limitations of the study, including its observational design. They also mentioned that they based their ascertainment of dissection mostly on results of noninvasive imaging, which could have led to underestimation. In addition, they excluded patients with strokes that affected the carotid and vertebrobasilar systems.

“We demonstrated that the risk of recurrence after PCAIS exceeds that after ACAIS; the subgroup of patients with PCAIS comprised 81.8% of the recurrences,” the researchers wrote. “Children with PCAIS may warrant increased monitoring. This study highlights the necessity for further research focused on prevention of recurrence, including the safety and efficacy of dual antithrombotic therapies.”