Differing risk factor profiles of ischemic stroke subtypes: evidence for a distinct lacunar arteriopathy?

Abstract

Background and Purpose Differences in risk factor profiles between lacunar and other ischemic stroke subtypes may provide evidence for a distinct lacunar arteriopathy, but existing studies have limitations. We overcame these by pooling individual data on 2875 patients with first-ever ischemic stroke from five collaborating prospective stroke registers that used similar, unbiased methods to define risk factors and classify stroke subtypes. Methods We compared risk factors between lacunar and non-lacunar ischemic strokes, altering the comparison groups in sensitivity analyses, and incorporated these data into a meta-analysis of published studies. Results Unadjusted and adjusted analyses gave similar results. We found a lower prevalence of cardioembolic source (adjusted OR: 0.33, 95% CI 0.24 to 0.46), ipsilateral carotid stenosis (OR: 0.21, 95% CI 0.14 to 0.30), and ischemic heart disease (IHD) (OR 0.75, 95% CI 0.58 to 0.97) in lacunar compared with non-lacunar patients, but no difference for hypertension, diabetes, or any other risk factor studied. Results were robust to sensitivity analyses and largely confirmed in our meta-analysis. Conclusions Hypertension and diabetes appear equally common in lacunar and non-lacunar ischemic stroke, but lacunar stroke is less likely to be caused by embolism from the heart or proximal arteries, and the lower prevalence of IHD in lacunar stroke provides further support for a non-atherosclerotic arteriopathy causing many lacunar ischemic strokes. Our findings have implications for how clinicians classify ischemic stroke subtypes, and highlight the need for further research into the specific causes of and treatments for lacunar stroke.