中国老年人握力和步速与衰弱关系的研究

Associations of grip strength and gait speed with frailty in older Chinese adults

目的 探索中国老年人握力和步速与衰弱间的关系,探寻握力与步速的预警值。方法 基于中国健康与养老追踪调查2011—2015年数据,纳入9 271名年龄≥60岁的老年人。本研究构建衰弱指数,采用广义估计方程结合限制性立方样条分析握力和步速与衰弱之间的关系,采用分段线性回归分别识别握力和步速与衰弱关联的转折点,以转折点为预警值将握力和步速分为低值组和正常组,采用线性回归和多分类逻辑回归的广义估计方程分析握力和步速组合与衰弱之间的关联。结果 衰弱指数随着握力和步速增大逐渐减小,且在握力和步速较低时减小幅度较大,较高时变缓。男性体重标化握力和步速的预警值分别为0.60 kg/kg和0.60 m/s,女性分别为0.47 kg/kg和0.66 m/s。与正常握力和正常步速相比,低握力和低步速组合与更高的衰弱风险相关。结论 中国老年人群的握力和步速与衰弱间均呈非线性负向关联。握力和步速的预警值能够快速识别衰弱高风险人群。

Objective To study the associations of grip strength and gait speed with frailty in older Chinese adults and to explore the thresholds of grip strength and gait speed.Methods This study included 9271 participants aged≥60 years from the China Health and Retirement Longitudinal Study during 2011-2015.A frailty index was constructed.GEEs incorporating RCS were used to analyze the associations of grip strength and gait speed with frailty.Piecewise linear regressions were used to identify the turning points of the associations.These turning points were used as thresholds to classify grip strength and gait speed into low and normal value groups.The associations of group combinations with frailty were analyzed using linear and multinomial logistic regression within the GEE.Results The frailty index decreased with the increase of grip strength and gait speed,and it decreased more rapidly at lower levels.The thresholds of weight-standardized grip strength and gait speed were 0.60 kg/kg and 0.60 m/s for males,respectively,and 0.47 kg/kg and 0.66 m/s for females,respectively.The combination of low grip strength and low gait speed were associated with higher risk of frailty compared with normal grip strength and gait speed.Conclusions Nonlinear negative associations of grip strength and gait speed with frailty in the older Chinese were detected.Thresholds for grip strength and gait speed enable rapid identification of individuals at high risk for frailty.