中年人锻炼再多休息不好，认知能力和不锻炼下降一样快

Joint associations of physical activity and sleep duration with cognitive ageing: longitudinal analysis of an English cohort study

Mikaela Bloomberg, Laura Brocklebank, Mark Hamer, Andrew Steptoe

The Lancet Healthy Longevity：2023/07/01

Background

Physical activity and sleep duration are key factors associated with cognitive function and dementia risk. How physical activity and sleep interact to influence cognitive ageing is not well explored. We aimed to examine the associations of combinations of physical activity and sleep duration with 10-year cognitive trajectories.

Methods

In this longitudinal study, we analysed data from the English Longitudinal Study of Ageing collected between Jan 1, 2008, and July 31, 2019, with follow-up interviews every 2 years. Participants were cognitively healthy adults aged at least 50 years at baseline. Participants were asked about physical activity and nightly sleep duration at baseline. At each interview, episodic memory was assessed using immediate and delayed recall tasks and verbal fluency using an animal naming task; scores were standardised and averaged to produce a composite cognitive score. We used linear mixed models to examine independent and joint associations of physical activity (lower physical activity or higher physical activity, based on a score taking into account frequency and intensity of physical activity) and sleep duration (short [<6 h], optimal [6–8 h], or long [>8 h]) with cognitive performance at baseline, after 10 years of follow-up, and the rate of cognitive decline.

Findings

We included 8958 respondents aged 50–95 years at baseline (median follow-up 10 years [IQR 2–10]). Lower physical activity and suboptimal sleep were independently associated with worse cognitive performance; short sleep was also associated with faster cognitive decline. At baseline, participants with higher physical activity and optimal sleep had higher cognitive scores than all combinations of lower physical activity and sleep categories (eg, difference between those with higher physical activity and optimal sleep vs those with lower physical activity and short sleep at baseline age 50 years was 0·14 SDs [95% CI 0·05–0·24]). We found no difference in baseline cognitive performance between sleep categories within the higher physical activity category. Those with higher physical activity and short sleep had faster rates of cognitive decline than those with higher physical activity and optimal sleep, such that their scores at 10 years were commensurate with those who reported low physical activity, regardless of sleep duration (eg, difference in cognitive performance after 10 years of follow-up between those with higher physical and optimal sleep and those with lower physical activity and short sleep was 0·20 SDs [0·08–0·33]; difference between those with higher physical activity and optimal sleep and those with lower physical activity and short sleep was 0·22 SDs [0·11–0·34]).

Interpretation

The baseline cognitive benefit associated with more frequent, higher intensity physical activity was insufficient to ameliorate the more rapid cognitive decline associated with short sleep. Physical activity interventions should also consider sleep habits to maximise benefis of physical activity for long-term cognitive health.

Funding

UK Economic and Social Research Council.

背景体力活动和睡眠时间是与认知功能和痴呆风险相关的关键因素。身体活动和睡眠是如何相互作用影响认知衰老的，目前还没有得到很好的研究。我们旨在研究身体活动和睡眠时间的组合与10年认知目标的关系。方法在这项纵向研究中，我们分析了2008年1月1日至2019年7月31日期间收集的英国老龄化纵向研究的数据，并每两年进行一次随访。参与者是认知健康的成年人，基线年龄至少为50岁。参与者被问及基线时的身体活动和夜间睡眠时间。在每次访谈中，使用即时和延迟回忆任务评估情景记忆，使用动物命名任务评估语言流利性；分数被标准化并取平均值以产生综合认知分数。我们使用线性混合模型来检验体力活动（较低的体力活动或较高的体力活动，基于考虑体力活动频率和强度的评分）和睡眠持续时间（短[lt；6 h]、最佳[6-8 h]或长[gt；8 h]）与基线认知表现的独立和联合关联，经过10年的随访，以及认知能力下降的比率。结果我们纳入了8958名基线年龄在50-95岁之间的受访者（中位随访时间为10年[IQR2-10]）。较低的体力活动和次优睡眠与较差的认知表现独立相关；睡眠时间短也与认知能力下降速度快有关。在基线时，具有较高体力活动和最佳睡眠的参与者的认知得分高于所有较低体力活动和睡眠类别的组合（例如，在基线年龄50岁时，具有较高体力活动和最优睡眠的参与者与具有较低体力活动和短睡眠的参与者之间的差异为0.14标准差[95%CI 0.05–0.24]）。我们发现，在较高体力活动类别中，睡眠类别之间的基线认知表现没有差异。那些体力活动量较大、睡眠时间较短的人的认知能力下降速度比那些体力活动度较高、睡眠时间最佳的人更快，因此他们在10年时的得分与那些报告体力活动量较低的人相当，无论睡眠时间长短（例如，10年随访后，高体力和最佳睡眠的人与低体力和短睡眠的人之间的认知表现差异为0.20 SDs[0.08-0.33]；高体力和最优睡眠的人和低体力和短时睡眠的人的差异为0.22 SDs[0.11-0.34]）解释与更频繁、更高强度的体育活动相关的基线认知益处不足以改善与睡眠不足相关的更快的认知下降。体育活动干预措施还应考虑睡眠习惯，以最大限度地提高体育活动对长期认知健康的益处。英国经济和社会研究委员会。

睡眠不足和锻炼较少都会导致认知能力下降。此前的研究显示，老年人规律性地锻炼身体能避免认知衰退。近期，一项新发表于《柳叶刀-老龄健康》（The Lancet Healthy Longevity）的研究显示，如果中老年人睡眠不足，那么锻炼带来的保护效果会下降。

研究人员在10年间评估了近9000名年龄超过50岁的成年人的认知功能情况。他们发现70岁以下的中老年人中进行很多的锻炼活动，但睡眠时间少于6小时的话，10年后，他们的认知能力会下降到和不进行锻炼的同龄人相当。不过如果年龄超过70岁，锻炼将能促进认知能力，且和睡眠时长无关。此外，研究还发现每天睡眠时间为6~8个小时，再加上较高水平的锻炼活动，能增强中老年人的认知功能。（University College London）