Department of Psychiatry, University Hospital of Heraklion, Heraklion, Crete, Greece.
Sleep Research and Treatment Center, Department of Psychiatry, Penn State University, Hershey, PA, USA.
J Alzheimers Dis. 2020;74(3):803-815. doi: 10.3233/JAD-190483.
Patients with dementia report excessive daytime sleep/sleepiness, which is associated with worse cognitive performance. Inflammatory markers may be elevated in patients with dementia and have been proposed as mediators of sleep/sleepiness.
To examine the association of objective daytime napping with cognitive performance and peripheral markers of inflammation in patients with dementia as compared to not cognitively impaired (NCI) controls.
A sub-sample of 46 patients with mild-to-moderate dementia and 85 NCI controls, were recruited from a large, population-based cohort of 3,140 elders (≥60 years) in Crete, Greece. All participants underwent medical history/physical examination, extensive neuropsychiatric and neuropsychological evaluation, 3-day 24 h actigraphy and a single morning measure of IL-6 and TNFα plasma levels. Comparisons of sleep parameters and inflammation markers between diagnostic groups, and between nappers and non-nappers within each diagnostic group, were conducted using ANCOVA controlling for demographics/related clinical factors. Associations between inflammatory markers, sleep variables, and neuropsychological performance were assessed within each group using partial correlation analysis controlling for confounders.
Patients with dementia slept 15 minutes longer during the day than NCI. Within dementia patients, nappers had significantly worse performance on autobiographic memory (p = 0.002), working memory (p = 0.007), episodic memory (p = 0.010), and assessment of daily function (p = 0.012) than non-nappers. Finally, IL-6 levels were significantly associated with nap duration within dementia patients who napped (r = 0.500, p = 0.01).
Daytime napping in patients with dementia is associated with worse cognitive performance and increased IL-6 levels. In dementia, objective daytime napping, may be a marker of the severity of the disease.
痴呆患者报告日间过度嗜睡/睡眠过多，这与认知表现更差有关。炎症标志物可能在痴呆患者中升高，并被提出作为睡眠/嗜睡的中介。
与认知正常（NCI）对照组相比，检查痴呆患者的客观日间小睡与认知表现和外周炎症标志物的关系。
从希腊克里特岛一个大型基于人群的 3140 名老年人（≥60 岁）队列中招募了 46 名轻度至中度痴呆患者和 85 名 NCI 对照组的亚样本。所有参与者都接受了病史/体检、广泛的神经精神病学和神经心理学评估、3 天 24 小时活动记录仪和单次早晨测量的白细胞介素 6（IL-6）和肿瘤坏死因子-α（TNFα）血浆水平。使用协方差分析（ANCOVA）控制人口统计学/相关临床因素，比较诊断组之间的睡眠参数和炎症标志物，以及每个诊断组内的小睡者和非小睡者之间的差异。使用偏相关分析（partial correlation analysis），在每个组内控制混杂因素，评估炎症标志物、睡眠变量和神经心理学表现之间的关系。
痴呆患者白天睡眠时间比 NCI 长 15 分钟。在痴呆患者中，小睡者在自传体记忆（p=0.002）、工作记忆（p=0.007）、情景记忆（p=0.010）和日常功能评估（p=0.012）方面的表现明显更差。最后，在小睡的痴呆患者中，IL-6 水平与小睡时间显著相关（r=0.500，p=0.01）。
痴呆患者的日间小睡与认知表现更差和 IL-6 水平升高有关。在痴呆中，客观的日间小睡可能是疾病严重程度的标志。
