Research Institute, California Pacific Medical Center, San Francisco, CA, USA.
Division of Epidemiology & Biostatistics, School of Public Health, University of California, Berkeley, Berkeley, CA, USA.
Sleep. 2021 Oct 11;44(10). doi: 10.1093/sleep/zsab119.
Disrupted daily rhythms are associated with mild cognitive impairment (MCI) and dementia. The specific nature of how rhythms and cognition are related, however, is unknown. We hypothesized characteristics from a nonparametric estimate of circadian rest-activity rhythm patterns would be associated to the development of MCI or dementia.
Wrist actigraphy from 1232 cognitively healthy, community-dwelling women (mean age 82.6 years) from the Study of Osteoporotic Fractures was used to estimate rest-activity patterns, including intradaily variability (IV), interdaily stability (IS), most active 10-hour period (M10), least active 5-hour period (L5), and relative amplitude (RA). Logistic regression examined associations of these predictors with 5-year incidence of MCI or dementia. Models were adjusted for potential confounders.
Women with earlier sleep/wake times had higher risk of dementia, but not MCI, (early vs. average L5 midpoint: OR, 1.66; 95% CI, 1.08-2.55) as did women with smaller day/night activity differentials (low vs. high RA: OR, 1.96; 95% CI, 1.14-3.35). IV, IS, and M10 were not associated with MCI or dementia.
The timing and difference in day/night amplitude, but not variability of activity, may be useful as predictors of dementia.
昼夜节律紊乱与轻度认知障碍（MCI）和痴呆有关。然而，目前尚不清楚节律和认知之间的具体关系。我们假设非参数估计的昼夜节律休息-活动节律模式的特征与 MCI 或痴呆的发展有关。
使用来自骨质疏松性骨折研究的 1232 名认知健康、社区居住的女性（平均年龄 82.6 岁）的腕部活动记录仪来估计休息-活动模式，包括日内可变性（IV）、日间稳定性（IS）、最活跃的 10 小时期（M10）、最不活跃的 5 小时期（L5）和相对幅度（RA）。逻辑回归分析了这些预测因子与 5 年 MCI 或痴呆发生率的关系。模型调整了潜在混杂因素。
早睡/起床时间较早的女性痴呆风险较高，但 MCI 风险较低（早睡/平均 L5 中点：OR，1.66；95%CI，1.08-2.55），昼夜活动差异较小的女性痴呆风险也较高（低 RA：OR，1.96；95%CI，1.14-3.35）。IV、IS 和 M10 与 MCI 或痴呆无关。
活动的时间和昼夜幅度差异，但不是可变性，可能是预测痴呆的有用指标。
