Cantero Jose L, Iglesias Juan E, Van Leemput Koen, Atienza Mercedes
Laboratory of Functional Neuroscience, CIBERNED (Network Center for Biomedical Research in Neurodegenerative Diseases), Pablo de Olavide University, Seville, Spain.
Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston. Basque Center on Cognition, Brain and Language, San Sebastian, Spain.
J Gerontol A Biol Sci Med Sci. 2016 Sep;71(9):1210-5. doi: 10.1093/gerona/glw022. Epub 2016 Mar 4.
Evidence suggests a link between the presence of subjective memory complaints (SMC) and lower volume of the hippocampus, one of the first regions to show neuropathological lesions in Alzheimer's disease. However, it remains unknown whether this pattern of hippocampal atrophy is regionally specific and whether SMC are also paralleled by changes in peripheral levels of amyloid-beta (Aβ).
The volume of hippocampal subregions and plasma Aβ levels were cross-sectionally compared between elderly individuals with (SMC(+); N = 47) and without SMC (SMC(-); N = 48). Significant volume differences in hippocampal subregions were further correlated with plasma Aβ levels and with objective memory performance.
Individuals with SMC exhibited significantly higher Aβ1-42 concentrations and lower volumes of CA1, CA4, dentate gyrus, and molecular layer compared with SMC(-) participants. Regression analyses further showed significant associations between lower volume of the dentate gyrus and both poorer memory performance and higher plasma Aβ1-42 levels in SMC(+) participants.
The presence of SMC, lower volumes of specific hippocampal regions, and higher plasma Aβ1-42 levels could be conditions associated with aging vulnerability. If such associations are confirmed in longitudinal studies, the combination may be markers recommending clinical follow-up in nondemented older adults.
有证据表明主观记忆障碍（SMC）的存在与海马体体积减小之间存在联系，海马体是阿尔茨海默病中最早出现神经病理损伤的区域之一。然而，这种海马体萎缩模式是否具有区域特异性，以及SMC是否也与外周β淀粉样蛋白（Aβ）水平的变化平行，目前尚不清楚。
对有（SMC(+)；N = 47）和无SMC（SMC(-)；N = 48）的老年人进行横断面比较，分析海马体亚区域体积和血浆Aβ水平。进一步将海马体亚区域的显著体积差异与血浆Aβ水平及客观记忆表现进行相关性分析。
与SMC(-)参与者相比，SMC患者的Aβ1-42浓度显著更高，而CA1、CA4、齿状回和分子层的体积更小。回归分析进一步表明，SMC(+)参与者中齿状回体积减小与较差的记忆表现及较高的血浆Aβ1-42水平之间存在显著关联。
SMC的存在、特定海马体区域体积减小以及血浆Aβ1-42水平升高可能是与衰老易感性相关的情况。如果在纵向研究中证实了这种关联，那么这些因素的组合可能是推荐对非痴呆老年人进行临床随访的标志物。
