LAUSR

Key Points Question What is the age-specific prevalence and prognosis of asymptomatic intracranial stenosis (ICS) in a population-based cohort of patients with transient ischemic attack (TIA) and minor stroke? Findings In this cohort study of 1368 patients with TIA and minor stroke, asymptomatic ICS was identified in 202 patients (14.8%) overall, with higher prevalence at older ages, reaching 34.6% at 90 years or older. In 155 patients with only asymptomatic ICS (11.3%), there was no increase in risk of ischemic stroke compared with those with no ICS, with 8 first recurrent events (5.2%) during 506 patient-years of follow-up and an annualized risk of same-territory ischemic stroke of 0.59%. Meaning The prevalence of asymptomatic ICS increases with age in patients with TIA and minor stroke and is greater than that of asymptomatic carotid stenosis, but asymptomatic ICS does not increase the short- or medium-term risk of distal recurrent ischemic stroke in patients receiving standard medical treatment.