Sex differences in large artery atherosclerotic stroke, a Korean study

Background & Objective: Sex differences in cerebral atherosclerosis and subsequent stroke have not been thoroughly investigated and conflicting data exist. The aim of this study was to investigate sex differences in the risk factors and distribution of large artery atherosclerotic stroke in a Korean population. Methods: We included consecutive acute ischemic stroke patients with symptomatic extracranial atherosclerosis (ECAS) or intracranial atherosclerosis (ICAS) based on brain and vascular imaging who presented at our hospital between January 2011 and December 2015. We then compared risk factor profiles and the proportion of symptomatic ECAS and ICAS between men and women. Results: Eight hundred and forty four patients were enrolled during the study period. The proportion of ECAS in men was notably higher than in women (19.4% in men vs. 9.3% in women; p < 0.001). A multiple regression analysis showed that male gender was a factor favoring ECAS (vs. ICAS, odds ratio [OR], 3.554; 95% confidence interval [CI], 2.175-5.808; p < 0.001). Age (OR, 1.051; 95% CI, 1.031-1.072; p = 0.001) and hyperlipidemia (OR, 2.330; 95% CI, 1.538-3.529; p < 0.001) were also factors favoring ECAS. However, after stratification by sex, the association was only significant in men. Conclusions: There is a sex difference in the distribution of atherosclerotic stroke. Sex may be an effect modifier of the association between atherosclerotic risk factors and atherosclerotic distribution. Neurology Asia 2016; 21(4) : 311 – 316 Address correspondence to: Joung-Ho Rha, MD, PhD, Department of Neurology, Inha University School of Medicine, 7-206, 3-ga, Choong-gu, Shinheungdong, Incheon 400-103, Korea. Tel: +82-32-890-3418, E-mail: [email protected] INTRODUCTION Sex differences regarding strokes have become increasingly recognized. Epidemiologic studies reveal that strokes are more common among men but that women have more severe manifestations of the disease. Sex differences may have implications for effective stroke prevention and treatment. Sex-specific guidelines have been developed for preventing stroke in women which includes recommendations on the stroke risk factors that are unique to and more common in women than men. Sex differences relevant to antiplatelet treatment also have been reported. With respect to ischemic stroke subtypes, women tend to have more cardioembolic strokes, while men have more lacunar and atherosclerotic strokes. Atherosclerotic stroke is one of the major causes of ischemic stroke. Cerebral atherosclerosis can be divided into extracranial atherosclerosis (ECAS) and intracranial atherosclerosis (ICAS). Little is known about sex differences in cerebral atherosclerosis and subsequent strokes due to conflicting data. Some studies have reported male predominance in ICAS, whereas others have reported that women more commonly develop ICAS. We aimed to investigate sex differences in the risk factors and distribution of large artery atherosclerotic stroke in a Korean population.