卫生研究

目的 研究营养不良风险在老年人失能影响因素中的中介作用。方法 数据来自2015年中国老年人营养与健康调查，采用多阶段分层整群抽样方法，从六个省级样本框中纳入3011名60岁及以上老年人作为最终分析样本。营养不良风险使用初始营养筛查量表(nutrition screening initial, NSI)评估，使用Mplus8软件的检验程序进行中介效应检验，并采用极大似然估计法(maximum likelihood)结合bootstrap法进行5000次重复抽样，估计偏倚校正95%置信区间。结果 营养不良风险在老年人失能影响因素中起到中介作用，主要效应包括：相对于独自吃住，与(孙)子女共同吃住的老年人营养不良风险较低，其失能风险也较低(b=-0.103,bootstrap 95%CI-0.197～-0.025,P<0.05);家庭人均年收入越高，老年人的营养不良风险越低，继而失能风险也更低(b=-0.124,bootstrap 95%CI-0.170～-0.086,P<0.001);有慢性病负担的老年人营养不良风险更高，继而失能风险也更高(b=0.099,bootstrap 95%CI 0.047～0.161,P<0.01);老年人营养知识水平对其营养不良风险产生反向影响，并借此降低其自身失能风险(b=-0.019,bootstrap 95%CI-0.033～-0.006,P<0.01)。结论 独自吃住、经济保障差、营养知识素养低、患有慢性病的老年人失能风险较高，与营养不良风险高有关。

OBJECTIVE To investigate whether malnutrition risk mediated the associations between selected factors and disability among older adults.METHODS Data were derived from the China Elderly Nutrition and Health Survey conducted in 2015. A multistage stratified cluster sampling method was used, and 3011 adults aged 60 years and older from six provincial-level sampling frames were included in the final analysis. The risk of malnutrition was assessed using the nutrition screening initiative(NSI) scale, widely implemented for community-dwelling older adults. Mediation effect analyses were performed using the testing procedures within Mplus 8 software. Parameter estimation utilized the Maximum Likelihood method, and bias-corrected 95%CI were estimated with 5000 bootstrap resamples.RESULTS Malnutrition risk significantly mediated several associations between selected factors and disability. Key findings included: Compared to those living and eating alone, older adults co-residing with children/grandchildren exhibited lower malnutrition risk, subsequently reducing disability risk(b=-0.103, bootstrap 95%CI-0.197--0.025, P<0.05). Higher annual household income per capita was associated with lower malnutrition risk, thereby reducing disability risk(b=-0.124, bootstrap 95%CI-0.170--0.086, P<0.001). Older adults with a chronic disease burden had higher malnutrition risk, which in turn elevated disability risk(b=0.099, bootstrap 95%CI 0.047-0.161, P<0.01). Higher nutrition knowledge levels inversely affected malnutrition risk, thereby lowering disability risk(b=-0.019, bootstrap 95%CI-0.033--0.006, P<0.01).CONCLUSION The elevated disability risk observed among older adults who live and eat alone, experience poor economic security, possess low nutrition knowledge, or suffer from chronic diseases may be related to their higher malnutrition risk.