Department of Radiology, The First Affiliated Hospital of Anhui Medical University, No. 218, Jixi Road, Shushan District, Hefei, 230022, China.
Department of Neurology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China.
BMC Neurol. 2021 Oct 30;21(1):423. doi: 10.1186/s12883-021-02445-9.
The Cognitive Reserve (CR) theory posits that brains with higher reserve can cope with more cerebral damage to minimize clinical manifestations. The aim of this study was to examine the effect of education (CR proxy) on brain structure and function in Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) patients and in cognitively healthy elderly (HC) individuals.
Fifty-seven AD patients, 57 aMCI patients and 48 HCs were included to investigate the relationships between education years and gray matter volume (GMV), regional homogeneity (ReHo) and functional connectivity (FC) in brain regions to show associations with both structure and function. Taking the severity of the disease into account, we further assessed the relationships in AD stratified analyses.
In AD group, the GMV of the dorsal anterior cingulate cortex (dACC) and ReHo in the left inferior temporal cortex (ITC) were inversely associated with education years, after adjustment for age, sex, Mini-Mental State Examination (MMSE), and total intracranial volume or head motion parameters. Seed-based FC analyses revealed that education years were negatively correlated with the FC between the left anterior ITC and left mid frontal cortex as well as right superior frontal cortex and right angular gyrus. Stratified analyses results indicated that this negative relation between education and GMV, ReHo, FC was mainly present in mild AD, which was attenuated in moderate AD and aMCI groups.
Our results support the CR theory, and suggest that CR may be protective against AD related brain pathology at the early stage of clinical dementia. These findings could provide the locus of CR-related functional brain mechanisms and a specific time-window for therapeutic interventions to help AD patients to cope better with the brain pathological damage by increasing CR.
认知储备（CR）理论认为，储备更高的大脑可以应对更多的大脑损伤，从而最大限度地减少临床表现。本研究旨在探讨教育（CR 代理）对阿尔茨海默病（AD）和遗忘型轻度认知障碍（aMCI）患者以及认知健康老年人（HC）大脑结构和功能的影响。
纳入 57 例 AD 患者、57 例 aMCI 患者和 48 例 HC，以探讨教育年限与大脑区域灰质体积（GMV）、区域同质性（ReHo）和功能连接（FC）之间的关系，以显示与结构和功能的关联。考虑到疾病的严重程度，我们还在 AD 分层分析中评估了这些关系。
在 AD 组中，背侧前扣带皮层（dACC）的 GMV 和左侧下颞叶（ITC）的 ReHo 与教育年限呈负相关，调整年龄、性别、简易精神状态检查（MMSE）、总颅内体积或头部运动参数后。基于种子的 FC 分析显示，教育年限与左侧前 ITC 与左侧中额皮质以及右侧额上回和右侧角回之间的 FC 呈负相关。分层分析结果表明，教育与 GMV、ReHo、FC 之间的这种负相关主要存在于轻度 AD 中，在中度 AD 和 aMCI 组中则减弱。
我们的研究结果支持 CR 理论，表明 CR 可能在临床痴呆早期对 AD 相关脑病理具有保护作用。这些发现为 CR 相关功能脑机制提供了作用部位，并为通过增加 CR 来帮助 AD 患者更好地应对大脑病理损伤提供了特定的治疗干预时间窗口。
