Department of Neurology, Mayo Clinic, Rochester, MN, USA.
Department of Neurology, Mayo Clinic, Rochester, MN, USA; Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA.
Sleep Med. 2017 Apr;32:236-243. doi: 10.1016/j.sleep.2016.08.023. Epub 2016 Nov 3.
Excessive daytime sleepiness (EDS) and fatigue increases with age. The aim of this study was to investigate the association between EDS and fatigue with cortical thickness and hippocampal volume in cognitively normal, late middle-aged and older adults. We performed a cross-sectional observational study of 1374 cognitively-normal subjects aged 50 years and older who had a structural MRI. Regional cortical thickness and hippocampal volume were measured. Multiple linear regression models were fit to explore associations between EDS and fatigue and structural MRI measures in different brain regions, adjusting for multiple covariates. EDS was defined as Epworth Sleepiness Scale ≥10. Fatigue severity was assessed with the Beck Depression Inventory-2. 208 participants had EDS, 27 had significant fatigue, and 11 had both. Participants with EDS or fatigue had significantly lower cognitive scores, more disturbed sleep, and medical comorbidities. The presence of EDS was associated with both global and regional atrophy, whereas fatigue was more associated with frontal and temporal changes. Cortical thinning predicted by EDS and fatigue was maximal in the temporal region with average reduction of 34.2 μm (95% CI, -54.1, -14.3; P = 0.001) and 90.2 μm (95% CI, -142.1, -38.2; P = 0.001), respectively. Fatigue was also associated with hippocampal volume reduction of -374.2 mm (95% CI, -670.8, -77.7; P = 0.013). Temporal cortical thinning predicted by presence of EDS and fatigue was equivalent to more than 3.5 and 9 additional years of aging, respectively. EDS and fatigue were associated with cortical thickness reduction primarily in regions with increased age-susceptibility, which may indicate accelerated brain aging.
日间过度嗜睡（EDS）和疲劳随着年龄的增长而增加。本研究旨在调查认知正常、中老年和老年人的 EDS 和疲劳与皮质厚度和海马体积之间的关系。我们对 1374 名认知正常、年龄在 50 岁及以上的受试者进行了横断面观察性研究，这些受试者均进行了结构磁共振成像。测量了局部皮质厚度和海马体积。采用多元线性回归模型，在调整了多个协变量后，探索 EDS 和疲劳与不同脑区结构 MRI 测量值之间的关系。EDS 定义为 Epworth 嗜睡量表≥10。疲劳严重程度采用 Beck 抑郁量表-2 进行评估。208 名参与者有 EDS，27 名有明显疲劳，11 名同时有 EDS 和疲劳。有 EDS 或疲劳的参与者认知评分显著降低，睡眠更紊乱，且合并有更多的医学共病。EDS 的存在与整体和区域性萎缩均相关，而疲劳则与额叶和颞叶变化更为相关。EDS 和疲劳预测的皮质变薄在颞叶最为明显，平均减少 34.2μm（95%置信区间，-54.1，-14.3；P=0.001）和 90.2μm（95%置信区间，-142.1，-38.2；P=0.001）。疲劳也与海马体积减少-374.2mm（95%置信区间，-670.8，-77.7；P=0.013）相关。EDS 和疲劳存在时预测的颞叶皮质变薄相当于多了 3.5 年和 9 年的衰老。EDS 和疲劳与皮质厚度的减少主要发生在易受年龄影响的区域，这可能表明大脑老化加速。
