Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA.
Neurology. 2011 Sep 6;77(10):951-8. doi: 10.1212/WNL.0b013e31822dc7e1. Epub 2011 Aug 24.
To determine the relationship between proton magnetic resonance spectroscopy ((1)H MRS) metabolites and β-amyloid (Aβ) load and the effects of Aβ load on the association between (1)H MRS metabolites and cognitive function in cognitively normal older adults.
We studied 311 cognitively normal older adults who participated in the population-based Mayo Clinic Study of Aging from January 2009 through September 2010. Participants underwent (11)C-Pittsburgh compound B (PiB) PET, (1)H MRS from the posterior cingulate gyri, and neuropsychometric testing to assess memory, attention/executive, language, and visual-spatial domain functions within 6 months. Partial Spearman rank order correlations were adjusted for age, sex, and education.
Higher PiB retention was associated with abnormal elevations in myoinositol (mI)/creatine (Cr) (partial r(s) = 0.17; p = 0.003) and choline (Cho)/Cr (partial r(s) = 0.13; p = 0.022) ratios. Higher Cho/Cr was associated with worse performance on Auditory Verbal Learning Test Delayed Recall (partial r(s) = -0.12; p = 0.04), Trail Making Test Part B (partial r(s) = 0.12; p = 0.04), Wechsler Adult Intelligence Scale-Revised (WAIS-R) Digit Symbol (partial r(s) = -0.18; p < 0.01), and WAIS-R Block Design (partial r(s) = -0.12; p = 0.03). Associations between (1)H MRS metabolites and cognitive function were not different among participants with high vs low PiB retention.
In cognitively normal older adults, the (1)H MRS metabolite ratios mI/Cr and Cho/Cr are associated with the preclinical pathologic processes in the Alzheimer disease cascade. Higher Cho/Cr is associated with worse performance on domain-specific cognitive tests independent of Aβ load, suggesting that Cho/Cr elevation may also be dependent on other preclinical dementia pathologies characterized by Cho/Cr elevation such as Lewy body or ischemic vascular disease in addition to Aβ load.
确定质子磁共振波谱（1H MRS）代谢物与β-淀粉样蛋白（Aβ）负荷之间的关系，以及 Aβ 负荷对认知功能正常的老年人中 1H MRS 代谢物与认知功能之间关系的影响。
我们研究了 311 名认知功能正常的老年人，他们参加了 2009 年 1 月至 2010 年 9 月的 Mayo 诊所老龄化人群研究。参与者接受了 11C-Pittsburgh 化合物 B（PiB）PET、后扣带回皮质的 1H MRS 以及神经心理测试，以在 6 个月内评估记忆、注意力/执行、语言和视觉空间域功能。部分 Spearman 秩相关系数经过年龄、性别和教育的调整。
较高的 PiB 保留与肌醇（mI）/肌酸（Cr）（部分 rs = 0.17；p = 0.003）和胆碱（Cho）/Cr（部分 rs = 0.13；p = 0.022）比值的异常升高有关。较高的 Cho/Cr 与听觉词语学习测试延迟回忆（部分 rs = -0.12；p = 0.04）、连线测试 B 部分（部分 rs = 0.12；p = 0.04）、韦氏成人智力量表修订版（WAIS-R）数字符号（部分 rs = -0.18；p < 0.01）和 WAIS-R 积木设计（部分 rs = -0.12；p = 0.03）的表现较差相关。在高 PiB 保留与低 PiB 保留的参与者之间，1H MRS 代谢物与认知功能之间的相关性没有差异。
在认知功能正常的老年人中，1H MRS 代谢物比 mI/Cr 和 Cho/Cr 与阿尔茨海默病级联的临床前病理过程有关。较高的 Cho/Cr 与特定领域认知测试的表现较差有关，而与 Aβ 负荷无关，这表明 Cho/Cr 的升高也可能依赖于其他以 Cho/Cr 升高为特征的临床前痴呆病理学，除了 Aβ 负荷之外，还包括路易体或缺血性血管疾病。
