天津市农村人群体质指数与脑卒中发病关系的前瞻性队列研究

The Prospective Cohort Study on the Relationship between Body Mass Index and the Incidence of Stroke in Jixian County of Tianjin

目的探讨天津市农村人群体质指数(BMI)与脑卒中发病的关系。方法以整群随机抽样的方法,于1991年9月在天津市蓟县某镇选取6个自然村15岁及以上常住人口4796人为基线研究对象,进行流行病学问卷调查,测量血压、身高、体重。用前瞻性队列研究的方法,每年随访队列人群的脑卒中事件,并进行全死因登记,至2009年9月共随访18年。分析不同BMI水平脑卒中发病的相对危险度(RR)。结果脑卒中发病与BMI水平明显有关,与正常体重组比较,体重过低组、超重组、肥胖组发生出血性卒中的RR值分别为2.7,1.9和3.5,缺血性卒中的发病危险在超重组和肥胖组明显增加,RR值分别为1.4和2.4;60岁以下人群体重过低组出血性卒中的发病风险最高(RR=10);60岁以上人群仅显示肥胖组有较高的缺血性卒中发病危险。结论农村肥胖人群有较高的脑卒中发病风险,特别是60岁以下人群,体重过低者易患出血性卒中。

Objective To investigate the relationship between body mass index （BMI） and the incidence of stroke among population in rural area, Tianjin, China. Methods A prospective cohort study of stroke incidence was conducted in Jixian county of Tianjin, China, from 1991 to 2009. The method of random cluster sampling was used to select 4 796 residents aged 15 and over, without known cardiovascular and cerebrovascular disease as the cohort population in baseline. All participants were interviewed to carry out the epidemiological questionnaire survey, and physical examination, including blood pressure, height, and weight. The Related Ratios （RR） of stroke was compared by different BMI category. Results There were significant association between BMI and the risk of stroke. Compared with the normal weight group, the RR of hemorrhagic stroke were 2.7, 1.9, and 3.5 in low weight group, overweight group, and obesity group, respectively. The results showed distinguished increased risks of ischemic stroke in overweight and obesity group with RR of 1.4 and 2.4, respectively. The risk of hemorrhagic stroke was the highest among those with low weight and aged under 60 years, RR=10.0, and risk of ischemic stroke was higher in those with obesity and aged 60 years and over. Conclusion Obesity would increase the risk of stroke in rural area, especially among those aged less than 60 years with low weight who were subject to the highest risk of hemorrhagic stroke.