Background The purpose of this study was to determine the dose-response association between habitual physical activity (PA) and cognitive function using a nationally representative dataset of U.S. older adults aged ≥ 60 years. Methods We used data from the 2011–2014 National Health and Nutrition Examination Survey (n = 2441, mean [SE] age: 69.1 [0.2] years, 54.7% females). Cognitive function was assessed using the Digit Symbol Substitution Test (DSST) and Animal Fluency Test (AFT). Habitual PA was collected using a tri-axial accelerometer worn on participants’ non-dominant wrist. PA was expressed as two metrics using monitor-independent movement summary (MIMS) units: the average of Daily MIMS (MIMS/day) and peak 30-minute MIMS (Peak-30MIMS; the average of the highest 30 MIMS mins/day). Sample weight-adjusted multivariable linear regression was performed to determine the relationship between each cognitive score and MIMS metric while adjusting for covariates. Results After controlling for covariates, for each 1000-unit increase in Daily MIMS, DSST score increased (β-coefficient [95% CIs]) by 0.67 (0.40, 0.93), while AFT score increased by 0.13 (0.04, 0.22); for each one-unit increase in Peak-30MIMS, DSST score increased by 0.56 (0.42, 0.70), while AFT score increased by 0.10 (0.05, 0.15), all p-values <0.001. When including both MIMS metrics in a single model, the association between Peak-30MIMS and cognitive scores remained significant (p-values <0.01), whereas Daily MIMS did not. Conclusions Our findings suggest that higher PA (both daily accumulated and peak effort) is associated with better cognitive function in the U.S. older adult population.

中文翻译：

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身体活动（每日 MIMS、峰值 30 分钟 MIMS）与老年人认知功能之间的剂量反应关联：NHANES 2011-2014

背景 本研究的目的是使用年龄≥ 60 岁的美国老年人的全国代表性数据集来确定习惯性身体活动 (PA) 与认知功能之间的剂量反应关联。方法 我们使用了 2011-2014 年全国健康和营养检查调查的数据（n = 2441，平均 [SE] 年龄：69.1 [0.2] 岁，54.7% 为女性）。使用数字符号替代测试 (DSST) 和动物流利测试 (AFT) 评估认知功能。使用佩戴在参与者非惯用手腕上的三轴加速度计收集习惯性 PA。PA 使用独立于监测器的运动摘要 (MIMS) 单位表示为两个指标：每日 MIMS 的平均值（MIMS/天）和 30 分钟 MIMS 峰值（Peak-30MIMS；最高 30 MIMS 分钟/天的平均值）。执行样本权重调整的多变量线性回归以确定每个认知评分与 MIMS 指标之间的关系，同时调整协变量。结果 在控制协变量后，每日 MIMS 每增加 1000 个单位，DSST 评分（β 系数 [95% CIs]）增加 0.67（0.40，0.93），而 AFT 评分增加 0.13（0.04，0.22）；Peak-30MIMS 每增加一个单位，DSST 得分增加 0.56 (0.42, 0.70)，而 AFT 得分增加 0.10 (0.05, 0.15)，所有 p 值 <0.001。当在单个模型中包括两个 MIMS 指标时，Peak-30MIMS 与认知分数之间的关联仍然显着（p 值 <0.01），而 Daily MIMS 则没有。