Effects of aging and Alzheimer's disease along the longitudinal axis of the hippocampus.
Effects of aging and Alzheimer's disease along the longitudinal axis of the hippocampus.
复制标题
DOI：
10.3233/jad-130011
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Head D
中科院分区：
文献类型：
--
作者：
Gordon BA;Blazey T;Benzinger TL;Head D
海马体通常被认为是一个统一的结构，但它沿其纵轴向周围皮层有不同的投影。这种异质性可能造成对病理影响的不同易感性，可能导致体积与年龄增长和阿尔茨海默病（AD）的不均匀关联。以前关于衰老和阿尔茨海默病对海马体细分的影响的研究已经产生了高度不同的结果。为了澄清这些不一致，我们对292名认知正常、37名非常轻度痴呆和18名轻度痴呆个体的大样本进行了海马体头部、身体和尾巴的检查，这些样本被分为两个独立的样本。正如文献中经常做的那样，我们描述了这些地区的定性模式，但通过明确测试定量差异来扩展这些结果。在每个认知正常个体的样本中，头部和身体比尾部表现出更大的年龄效应。在每个对比AD和认知正常个体的样本中，所有三个区域都显示出明显的体积减少，对头部的影响最大。当检查痴呆症的严重程度时，海马头部表现出进行性体积损失，而身体和尾巴则没有。在独立样本中，检测衰老和AD的结果模式相对一致。这些结果表明，随着年龄的增长和阿尔茨海默病的发生，海马体中存在着从前到后的丧失梯度。
The hippocampus is often treated as a uniform structure, but possesses differential projections to surrounding cortex along its longitudinal axis. This heterogeneity could create varied susceptibility to pathological influences, potentially leading to non-uniform volumetric associations with advancing age and Alzheimer’s disease (AD). Previous examinations of aging and AD effects on hippocampal subdivisions have produced highly discrepant findings. To clarify these inconsistencies, we examined the hippocampal head, body, and tail in a large sample of 292 cognitively normal, 37 very mildly demented, and 18 mildly demented individuals, divided into two independent samples. As often done in the literature, we characterized qualitative patterns across these regions, but extended these results by explicitly testing for quantitative differences. In each sample of cognitively normal individuals, the head and body demonstrated greater age effects than the tail. In each sample contrasting AD and cognitively normal individuals, all three regions showed significant volume reductions, with the greatest effect on the head. When examining increasing severity of dementia, the hippocampal head showed progressive volume loss, while the body and tail did not. The patterns of results examining both aging and AD were relatively consistent across the independent samples. These results indicate that there is an anterior-to-posterior gradient of loss within the hippocampus with both advancing age and AD.