Medical School of Chinese PLA, Beijing, China.
Institute of Geriatrics, Beijing Key Laboratory of Aging and Geriatrics, National Clinical Research Center for Geriatrics Diseases, State Key Laboratory of Kidney Disease, The 2nd Medical Center of Chinese PLA General Hospital, Beijing, China.
Front Endocrinol (Lausanne). 2021 Jun 29;12:620261. doi: 10.3389/fendo.2021.620261. eCollection 2021.
Body mass index (BMI) and cognitive function are independent predictors of mortality risk. However, little is known about the combined impact of BMI and cognitive function on the risk of all-cause mortality in older adults. In this study, we aimed to examine the associations between BMI, cognitive function, and all-cause mortality, including between-factor interactions, in the general population of older adults in China.
We used the data between 2011 and 2018 from the Chinese Longitudinal Healthy Longevity Survey that included adults aged ≥65 years residing in the 23 provinces of China. The association between BMI and cognitive function on all-cause mortality was examined with the Cox proportional hazards regression model.
The study included 8,293 Chinese older adults. Low BMI (underweight) and cognitive impairment were associated with the highest risk of death after adjustments [hazard ratio (HR) = 2.18; 95% confidence interval (CI), 1.96-2.41]; this combined effect was more prominent among adults aged <100 years and women. In addition, there was an interaction effect of BMI and cognitive impairment on all-cause mortality (P <0.001). Concurrently, among older adults with normal cognition, the risk of mortality related to underweight was higher than among their cognitively impaired counterparts [55% (normal cognition) 38% (cognitive impairment)].
Low BMI (underweight) and cognitive impairment were independently and jointly associated with increased risk of all-cause mortality among Chinese older adults, and females showed a stronger effect in this association. The association between BMI and mortality was more pronounced in the participants with normal cognition than in their cognitively impaired counterparts.
体重指数（BMI）和认知功能是死亡率的独立预测因素。然而，人们对 BMI 和认知功能对中国老年人群全因死亡率的综合影响知之甚少。在这项研究中，我们旨在研究 BMI、认知功能与全因死亡率之间的关系，包括两者之间的相互作用，以了解中国老年人群的一般情况。
我们使用了 2011 年至 2018 年期间来自中国纵向健康长寿调查的数据，该调查包括中国 23 个省份年龄在 65 岁及以上的成年人。使用 Cox 比例风险回归模型检验 BMI 和认知功能与全因死亡率之间的关系。
本研究纳入了 8293 名中国老年人。在调整后，低 BMI（体重不足）和认知障碍与死亡风险最高相关（风险比[HR] = 2.18；95%置信区间[CI]，1.96-2.41）；这种联合效应在年龄<100 岁和女性中更为明显。此外，BMI 和认知障碍对全因死亡率存在交互作用（P<0.001）。同时，在认知正常的老年人中，与认知障碍相比，体重不足与死亡率相关的风险更高[55%（认知正常）比 38%（认知障碍）]。
低 BMI（体重不足）和认知障碍与中国老年人全因死亡率的增加独立且共同相关，女性在这种关联中表现出更强的作用。与认知障碍相比，在认知正常的参与者中，BMI 与死亡率的相关性更为明显。
