METHODS: The outcome was low cognitive performance defined as being >1 standard deviation below average age/sex/education internally normalized composite cognitive performance levels assessed in the Hispanic Community Health Study/Study of Latinos. Analyses included 1006 individuals who had sufficient sleep-wake measurements about 2years later (mean age=54.9, standard deviation= 5.1; 68.82% female). We evaluated associations of 31 sleep-wake variables with low cognitive performance using separate logistic regressions.
RESULTS: In individual models, the strongest sleep-wake correlates of low cognitive performance were measures of weaker and unstable 24-hour rhythms; greater 24-hour fragmentation; longer time-in-bed; and lower rhythm amplitude. One standard deviation worse on these sleep-wake factors was associated with ∼20%-30% greater odds of having low cognitive performance. In an internally cross-validated prediction model, the independent correlates of low cognitive performance were: lower Sleep Regularity Index scores; lower pseudo-F statistics (modellability of 24-hour rhythms); lower activity rhythm amplitude; and greater time in bed. Area under the curve was low/moderate (64%) indicating poor predictive utility.
CONCLUSIONS: The strongest sleep-wake behavioral correlates of low cognitive performance were measures of longer time-in-bed and irregular/weak rhythms. These sleep-wake assessments were not useful to identify previous low cognitive performance. Given their potential modifiability, experimental trials could test if targeting midlife time-in-bed and/or irregular rhythms influences cognition.
方法:结果是低认知表现,定义为在西班牙裔社区健康研究/拉丁美洲人研究中评估的年龄/性别/教育内部标准化综合认知表现水平以下>1个标准差。分析包括1006名大约2年后有足够睡眠-觉醒测量的个体(平均年龄=54.9,标准偏差=5.1;68.82%女性)。我们使用单独的逻辑回归评估了31个睡眠-觉醒变量与低认知表现的关联。
结果:在单个模型中,低认知表现的最强睡眠-觉醒相关指标是较弱和不稳定的24小时节律;更大的24小时碎片;更长的卧床时间;和更低的节律幅度.这些睡眠-觉醒因素的一个标准差更差,与认知能力低下的几率增加了20%-30%。在内部交叉验证的预测模型中,认知能力低下的独立相关性为:睡眠规律指数评分较低;伪F统计(24小时节律的模型性)较低;活动节律幅度较低;卧床时间较长.曲线下面积低/中等(64%),表明预测效用差。
结论:低认知表现的最强的睡眠-觉醒行为相关指标是卧床时间较长和节律不规则/弱。这些睡眠-觉醒评估对识别先前的低认知表现没有帮助。鉴于它们潜在的可修饰性,实验性试验可以测试针对中年卧床时间和/或不规则节律是否会影响认知。