Capsular Warning Syndrome: Features, Risk Profile, and Prognosis in a Large Prospective TIA Cohort

Introduction: Features and prognosis of capsular warning syndrome (CWS) have been poorly investigated prospectively. Aims: The study aimed to characterize CWS clinical features, risk profile, short- and long-term prognosis, among a large TIA cohort. Methods: Prospective cohort study of consecutive TIAs was conducted from August 1, 2010, to December 31, 2017. Demographic and clinical characteristics, risk profile, primary (stroke and composite outcome) and secondary (TIA recurrence, cerebral hemorrhage, new onset atrial fibrillation) outcomes were compared between CWS, lacunar (L), and nonlacunar (NL) TIAs. Results: 1,035 patients (33 CWS, 189 L-TIAs, 813 NL-TIAs) were enrolled. Newly diagnosed (ND) hypertension, hypercholesterolemia, cigarette smoking, and leukoaraiosis were independent risk factors of CWS (p < 0.05). CWS showed the highest stroke (30.3% vs. 0.5% and 1.5% for L-TIAs and NL-TIAs, respectively) and composite outcome risk at follow-up (p < 0.001), but better 3-month post-stroke prognosis (mRS 0–2 90.0% vs. 36.8%; p = 0.002). CWS-related stroke mostly occurred