Department of Neurology,University of Miami Miller School of Medicine, Miami, FL,USA.
Department of Psychology,University of Miami, Miami, FL,USA.
Int Psychogeriatr. 2019 Jun;31(6):779-788. doi: 10.1017/S1041610219000292. Epub 2019 Apr 22.
ABSTRACTObjectives:Frailty is associated with cognitive decline in older adults. However, the mechanisms explaining this relationship are poorly understood. We hypothesized that sleep quality may mediate the relationship between frailty and cognition.
154 participants aged between 50-90 years (mean = 69.1 years, SD = 9.2 years) from the McKnight Brain Registry were included.
Participants underwent a full neuropsychological evaluation, frailty and subjective sleep quality assessments. Direct relationships between frailty and cognitive function were assessed using linear regression models. Statistical mediation of these relationships by sleep quality was assessed using nonparametric bootstrapping procedures.
Frailty severity predicted weaker executive function (B = -2.77, β = -0.30, 95% CI = -4.05 - -1.29) and processing speed (B = -1.57, β = -0.17, 95% CI = -3.10 - -0.16). Poor sleep quality predicted poorer executive function (B = -0.47, β = -0.21, 95% CI = -0.79 - -0.08), processing speed (B = -0.64, β = -0.28, 95% CI = -0.98 - -0.31), learning (B = -0.42, β = -0.19, 95% CI = -0.76 - -0.05) and delayed recall (B = -0.41, β = -0.16, 95% CI = -0.80 - -0.31). Poor sleep quality mediated the relationships between frailty severity and executive function (B = -0.66, β = -0.07, 95% CI = -1.48 - -0.39), learning (B = -0.85, β = -0.07, 95% CI = -1.85 - -0.12), delayed recall (B = -0.47, β = -0.08, 95% CI = -2.12 - -0.39) and processing speed (B = -0.90, β = -0.09, 95% CI = -1.85 - -0.20).
Relationships between frailty severity and several cognitive outcomes were significantly mediated by poor sleep quality. Interventions to improve sleep quality may be promising avenues to prevent cognitive decline in frail older adults.
背景：衰弱与老年人认知能力下降有关。然而，其相关机制尚不清楚。我们假设睡眠质量可能在衰弱与认知之间起中介作用。
参与者：共纳入 154 名年龄在 50-90 岁（平均=69.1 岁，标准差=9.2 岁）的 McKnight 大脑登记研究参与者。
方法：参与者接受了全面的神经心理学评估、衰弱和主观睡眠质量评估。使用线性回归模型评估衰弱与认知功能之间的直接关系。使用非参数自举程序评估睡眠质量对这些关系的统计中介作用。
结果：衰弱严重程度与执行功能（B=-2.77，β=-0.30，95%置信区间=-4.05 至-1.29）和处理速度（B=-1.57，β=-0.17，95%置信区间=-3.10 至-0.16）较差相关。较差的睡眠质量与较差的执行功能（B=-0.47，β=-0.21，95%置信区间=-0.79 至-0.08）、处理速度（B=-0.64，β=-0.28，95%置信区间=-0.98 至-0.31）、学习（B=-0.42，β=-0.19，95%置信区间=-0.76 至-0.05）和延迟回忆（B=-0.41，β=-0.16，95%置信区间=-0.80 至-0.31）较差相关。较差的睡眠质量在衰弱严重程度与执行功能（B=-0.66，β=-0.07，95%置信区间=-1.48 至-0.39）、学习（B=-0.85，β=-0.07，95%置信区间=-1.85 至-0.12）、延迟回忆（B=-0.47，β=-0.08，95%置信区间=-2.12 至-0.39）和处理速度（B=-0.90，β=-0.09，95%置信区间=-1.85 至-0.20）之间的关系中起显著的中介作用。
结论：衰弱严重程度与多种认知结果之间的关系在很大程度上受到睡眠质量较差的影响。改善睡眠质量的干预措施可能是预防衰弱老年人认知能力下降的有前途的途径。
