Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.
Australian Alzheimer's Research Foundation, Perth, Western Australia, Australia.
J Alzheimers Dis. 2021;81(3):1039-1052. doi: 10.3233/JAD-201243.
Previous research has identified a small subgroup of older adults that maintain a high level of cognitive functioning well into advanced age. Investigation of those with superior cognitive performance (SCP) for their age is important, as age-related decline has previously been thought to be inevitable.
Preservation of cortical thickness and volume was evaluated in 76 older adults with SCP and 100 typical older adults (TOAs) assessed up to five times over six years.
Regions of interest (ROIs) found to have been associated with super-aging status (a construct similar to SCP status) in previous literature were investigated, followed by a discovery phase analyses of additional regions. SCPs were aged 70 + at baseline, scoring at/above normative memory (CVLT-II) levels for demographically similar individuals aged 30-44 years old, and in the unimpaired range for all other cognitive domains over the course of the study.
In linear mixed models, following adjustment for multiple comparisons, there were no significant differences between rates of thinning or volume atrophy between SCPs and TOAs in previously identified ROIs, or the discovery phase analyses. With only amyloid-β negative individuals in the analyses, again there were no significant differences between SCPs and TOAs.
The increased methodological rigor in classifying groups, together with the influence of cognitive reserve, are discussed as potential factors accounting for our findings as compared to the extant literature on those with superior cognitive performance for their age.
先前的研究已经确定了一小部分老年人，他们在进入老年后仍能保持高水平的认知功能。对具有超龄认知表现（SCP）的人群进行研究很重要，因为之前人们认为与年龄相关的衰退是不可避免的。
评估 76 名具有 SCP 的老年人和 100 名典型老年人（TOAs）的皮质厚度和体积保留情况，这些老年人在六年的时间里被评估了多达五次。
对先前文献中与超龄状态相关的感兴趣区域（ROIs）进行了调查，随后对其他区域进行了发现阶段分析。SCP 的基线年龄为 70 岁以上，在认知领域的其他方面均保持正常的情况下，其记忆（CVLT-II）水平与 30-44 岁年龄相似的人群的标准水平相当，且在研究过程中保持在正常范围内。
在线性混合模型中，在进行多次比较调整后，在先前确定的 ROI 或发现阶段分析中，SCP 和 TOA 之间的变薄或体积萎缩率没有显著差异。在仅对淀粉样蛋白-β阴性个体进行分析时，SCP 和 TOA 之间也没有显著差异。
对分组进行分类的方法更加严谨，再加上认知储备的影响，这些因素可能解释了我们的研究结果与年龄相关的认知表现优异的文献相比存在差异的原因。
