我国中老年人肥胖与死亡风险的关系

Association between obesity and death risk among Chinese adults aged 45 and over

目的探讨≥45岁中老年人体质量指数(body mass index,BMI)与死亡风险的关系。方法基于中国健康与养老追踪调查(China Health and Retirement Longitudinal Study,CHARLS)数据,对13283名年龄45~100岁的中老年人进行研究,探讨BMI与死亡风险之间的关系。根据中国的肥胖标准,用BMI和腰围两项指标来评估肥胖。结果BMI与全因死亡风险大致呈反向J型关系。COX回归结果显示,与体质量正常组相比,偏瘦组死亡风险增大(HR=1.88,95%CI:1.61~2.21,P<0.01);超重组、肥胖组的死亡风险降低(HR=0.76,95%CI:0.66~0.88,P<0.01;HR=0.66,95%CI:0.53~0.82,P<0.01)。腰围与全因死亡风险之间成负相关。结论适当增加体质量,能降低中国中老年人的死亡风险。目前的健康体质量范围可能不适合中国的中老年人,对该群体BMI的解释应与其他共存疾病、功能能力和民族差异相结合。

Objective To elucidate the association between obesity and death risk in adults aged 45 years and over in China.Methods Data of 13283 study participants aged 45-100 years were retrieved from the database of China Health and Retirement Longitudinal Study(CHARLS),a seven year prospective cohort study,and the association between obesity and death risk was analyzed.Obesity was defined using body mass index(BMI)and waist circumference(WC)according to the Chinese obesity standard.Results The relationship between BMI(as a continuous variable)and all-cause death risk was found to be reversed J shaped.COX regression analysis showed that compared to participants with normal BMI,those with underweight had significantly greater adjusted risk of all-cause mortality(HR=1.88,95%CI:1.61-2.21,P<0.01),while participants with overweight and obesity had significantly lower adjusted-risk of all-cause mortality(HR=0.76,95%CI:0.66-0.88,P<0.01;HR=0.66,95%CI:0.53-0.82,P<0.01).Waist circumference was negatively associated with all-cause mortality.Conclusions For middle-aged and the elderly in China,proper weight gain can reduce the risk of death.The current BMI range may not be appropriate for the middle-aged and the elderly in China,therefore,the interpretation of BMI should be combined with other coexisting diseases and functional capacity and ethnic differences.