Burden of coronary artery disease predicts mortality in ischaemic stroke patients: The Norwegian Stroke in the Young Study
Abstract Body (Do not enter title and authors here): Background and purpose: Earlier European studies in young stroke patients have identified coronary artery disease (CAD) as a contributor to mortality. In the present Norwegian Stroke in the Young Study (NOR-SYS) sub-study we aim to investigate the true prevalence of CAD and the impact on mortality and event-free survival in young and middle-aged stroke survivors. Methods: Between September 2010 and December 2015, a total of 385 patients (15-60 years) with ischemic stroke were included. Clinical characteristics, echocardiographic and coronary imaging (angiography or cardiac CT) data, and arterial stiffness indices (pulse wave velocity, carotid intima media thickness and femoral plaque) were analysed. No CAD was defined as no history of CAD and no femoral artery plaque on vascular ultrasound (US) or negative coronary imaging. Coronary imaging was done if history of CAD or femoral plaque on US. Results: Mean (±SD) age was 49.6 (±9.7) year, 68.1% males. The overall prevalence of CAD was 25.2% (n=97) (non-obstructive 9.6% [n=37] and obstructive 15.6% [n=60]). In a subsample of patients (n=58) without a previous history of CAD or symptoms, who underwent cardiac CT as part of screening following femoral plaque on US, 46% (n=27) had non-obstructive CAD and 28% (n=16) had obstructive CAD. When further classified 17.2% had one-vessel disease, 3.4% two-vessel disease and 6.9% three-vessel disease. During a mean (±SD) follow-up of 9.8 (±2.5) years, 35 patients (9.1%) died (3.1% one-year mortality) and 83 (21.6%) reached a composite endpoint of new stroke, myocardial infarction or death, while 63 (16.4%) reached a composite endpoint of new stroke or death. In a Kaplan-Meier curve event-free survival was significantly lower in patients with CAD versus no-CAD (Figure). This was confirmed by multivariate cox regression models, in which CAD was an independent predictor of all-cause mortality (HR 2.25; 95% CI 1.07-4.47, p= 0.033) and composite endpoint of death or recurrent ischemic stroke (HR 3.26; 95% CI 1-47-7.23, p=0.004) adjusted for potential confounders. Conclusions: In the present study of young and middle-aged ischemic stroke survivors, a quarter of patients had CAD. In patients without previous history of CAD or symptoms who underwent cardiac CT on the basis of femoral plaque on US, nearly a half had non-obstructive and one-third obstructive CAD. CAD, and in particular obstructive CAD, was a major independent predictor of mortality and recurrent stroke.