Lu Ming, Ye Weimin, Adami Hans-Olov, Weiderpass Elisabete
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Cerebrovasc Dis. 2008;25(6):517-25. doi: 10.1159/000131669. Epub 2008 May 15.
The association between alcohol intake, cigarette smoking and risk of stroke amongst women remains unclear, especially in young women.
This prospective cohort study included 45,449 Swedish women aged 30-50 years free of stroke and heart diseases at enrollment in 1991 and 1992. Information on drinking and smoking habits at enrollment was collected using a questionnaire. Incident stroke cases were identified through cross-linkage to the Swedish Inpatient Register. Cox proportional hazards regression models were used to calculate relative risks (RR) and their corresponding 95% confidence intervals (CIs).
During an average of 11 years of follow-up, 170 incident stroke cases, of which 111 ischemic and 47 hemorrhagic, were identified. Compared to abstainers, risk of stroke was reduced among women consuming less than 20 g (RR = 0.7, 95% CI 0.5-1.0) or 20-69.9 g (RR = 0.5, 95% CI 0.3-0.7) of alcohol per week, whilst women who consumed > or =70 g of alcohol per week had a nonsignificant reduced relative risk (RR = 0.7, 95% CI 0.4-1.3). We found no difference in stroke risk according to the types of alcoholic beverage consumed. Compared with never smokers, there was an increased risk of all strokes among current smokers of 1-9 cigarettes/day (RR = 2.3, 95% CI 1.5-3.7) or > or =10 cigarettes/day (RR = 2.6, 95% CI 1.7-4.1). The observed smoking-related excess risks were confined mainly to ischemic stroke. Former smokers had a 50-60% increase in RRs of both ischemic and hemorrhagic stroke. In stratified analyses, current smokers had a 4-fold excess risk if they were nondrinkers (RR = 4.2; 95% CI 2.2-7.8) but a lower risk (RR = 1.5; 95% CI 0.8-2.4) if they drank in moderation. Compared to never drinkers and never smokers, women who drank in moderation were also at reduced risk (RR = 0.6; 95% CI 0.3-1.1). These interactions were statistically significant (p = 0.001).
Light to moderate alcohol intake, regardless of type of alcoholic beverage, reduces risk of stroke among women under 60 years of age, in particular those women who were never smokers. Smoking increases the risk of stroke, especially ischemic stroke.
饮酒、吸烟与女性中风风险之间的关联尚不清楚，尤其是在年轻女性中。
这项前瞻性队列研究纳入了1991年和1992年入组时年龄在30至50岁、无中风和心脏病的45449名瑞典女性。通过问卷调查收集入组时的饮酒和吸烟习惯信息。通过与瑞典住院患者登记系统交叉链接识别出中风病例。采用Cox比例风险回归模型计算相对风险（RR）及其相应的95%置信区间（CI）。
在平均11年的随访期间，共识别出170例中风病例，其中111例为缺血性中风，47例为出血性中风。与不饮酒者相比，每周饮酒少于20克（RR = 0.7，95% CI 0.5 - 1.0）或20 - 69.9克（RR = 0.5，95% CI 0.3 - 0.7）的女性中风风险降低，而每周饮酒≥70克的女性相对风险降低不显著（RR = 0.7，95% CI 0.4 - 1.3）。我们发现，根据饮用的酒精饮料类型，中风风险没有差异。与从不吸烟者相比，目前每天吸1 - 9支烟（RR = 2.3，95% CI 1.5 - 3.7）或≥10支烟（RR = 2.6，95% CI 1.7 - 4.1）的吸烟者发生所有中风的风险增加。观察到的与吸烟相关的额外风险主要局限于缺血性中风。既往吸烟者发生缺血性和出血性中风的RR增加50 - 60%。在分层分析中，目前吸烟者如果不饮酒，风险增加4倍（RR = 4.2；95% CI 2.2 - 7.8），但如果适度饮酒，风险较低（RR = 1.5；95% CI 0.8 - 2.4）。与从不饮酒和从不吸烟者相比，适度饮酒的女性中风风险也降低（RR = 0.6；95% CI 0.3 - 1.1）。这些相互作用具有统计学意义（p = 0.001）。
轻度至中度饮酒，无论饮用何种酒精饮料，均可降低60岁以下女性的中风风险，尤其是那些从不吸烟的女性。吸烟会增加中风风险，尤其是缺血性中风。
