[Association of body mass index and waist circumference with risk of ischemic stroke in adults in China: a prospective cohort study].

Objective: To explore the relationship between body mass index (BMI), waist circumference (WC) and the risk for ischemic stroke in adults in China. Methods: A total of 36 632 adults were selected from 60 surveillance areas (25 urban surveillance areas and 35 rural surveillance areas) in China Chronic Disease Surveillance Project in 2010 for a follow up study from 2016 to 2017 based on the baseline data in 2010. The follow up was completed for 27 762 adults. Cox proportional hazard regression model was used to analyze the association of body mass index and waist circumference with the risk for ischemic stroke in different populations. The death and hypercholesterolemia cases were excluded by sensitivity analysis. Results: A total of 26 907 adults were included in the analysis. During the follow up period, 1 128 ischemic stroke events were observed (491 in men and 637 in women). After adjusting the related confounding factors and taking normal BMI/normal WC group as the reference, the risk for ischemic stroke increased by 50% in normal BMI/abdominal obesity group (HR=1.50, 95%CI:1.07-2.08), 51% in overweight/abdominal obesity group (HR=1.51, 95%CI:1.20-1.91), 46% in obesity/abdominal obesity group (HR=1.46, 95%CI:1.09-1.96), and 63% in normal BMI/abdominal obesity group (HR=1.63, 95%CI:1.12-2.38), 56% in overweight/abdominal obesity group (HR=1.56, 95%CI: 1.20-2.03) and 45% in obesity/abdominal obesity group (HR=1.45, 95%CI: 1.05-2.01) respectively in men and in men with CVD risk factors. There was no increased risks in the overweight/normal WC group. The risk increased by 40% in overweight/abdominal obesity group (HR=1.40, 95%CI:1.15-1.72) and 46% in obesity/abdominal obesity group (HR=1.46, 95%CI:1.16-1.83), and 35% in overweight/abdominal obesity group (HR=1.35, 95%CI:1.08-1.69) and 30% in obesity/abdominal obesity group (HR=1.30, 95%CI:1.01-1.67) respectively in women and women with CVD risk factors. There were no risk increases in overweight/normal WC group and normal BMI/abdominal obesity group. Sensitivity analysis results showed no change. Conclusion: Overweight/obesity with abdominal obesity or abdominal obesity alone could increase the risk for stroke in men, and overweight/obesity with abdominal obesity could increase the risk for ischemic stroke in women; suggesting that BMI and WC should be used jointly to evaluate obesity in population for weight control to prevent ischemic stroke.目的： 分析我国成年人BMI和腰围与缺血性卒中发病风险的关联。 方法： 从2010年中国慢性病监测项目选取60个监测点人群（城市监测点25个、农村监测点35个）作为本次研究对象，共计36 632人。将2010年中国慢性病监测项目数据作为基线数据。2016-2017年对该60个监测点人群进行随访，实际完成者27 762人。采用Cox比例风险回归模型分析不同人群BMI和腰围与缺血性卒中发病风险比，敏感性分析将死亡者和高胆固醇血症者剔除。 结果： 共纳入26 907人进入分析，随访期间观察到缺血性卒中事件1 128例（男性491例，女性637例）。调整相关混杂因素后，以BMI正常/腰围正常者为参照，全人群和男性具有CVD危险因素人群，BMI正常/腹型肥胖组、超重/腹型肥胖组和肥胖/腹型肥胖组缺血性卒中发病风险分别增加50%（HR=1.50，95%CI：1.07~2.08）、51%（HR=1.51，95%CI：1.20~1.91）、46%（HR=1.46，95%CI：1.09~1.96）和63%（HR=1.63，95%CI：1.12~2.38）、56%（HR=1.56，95%CI：1.20~2.03）、45%（HR=1.45，95%CI：1.05~2.01），超重/腰围正常组未见发病风险增加；女性全人群和女性CVD危险因素人群，超重/腹型肥胖组和肥胖/腹型肥胖组发病风险分别增加40%（HR=1.40，95%CI：1.15~1.72）、46%（HR=1.46，95%CI：1.16~1.83）和35%（HR=1.35，95%CI：1.08~1.69）、30%（HR=1.30，95%CI：1.01~1.67），超重/腰围正常组和BMI正常/腹型肥胖组未见发病风险增加。敏感性分析结果未见变化。 结论： 在男性人群中，超重/肥胖且腹型肥胖或单纯腹型肥胖缺血性卒中发病风险增加；在女性人群中，超重/肥胖且腹型肥胖发病风险增加；提示在控制体重预防缺血性卒中，应将BMI和腰围进行结合来评价人群肥胖情况。.