Laboratory of Epidemiology Neuroimaging and Telemedicine, and Unit for the Clinical Translation of Research, IRCCS Centro San Giovanni di Dio FBF, Brescia, Italy.
Alzheimers Dement. 2013 Nov;9(6):677-86. doi: 10.1016/j.jalz.2012.09.016. Epub 2013 Jan 30.
To capitalize on data from different clinical series to compare sensitivity and specificity of individual biomarkers for predicting mild cognitive impairment (MCI) progression to Alzheimer's disease (AD).
Medial temporal atrophy, cortical hypometabolism, and cerebrospinal fluid biomarkers were assessed in 18 patients with mild cognitive impairment (MCI) with prodromal AD (pAD; conversion time, 26 ± 12 months) and 18 stable MCI (sMCI) patients from the Translational Outpatient Memory Clinic cohort, as well as in 24 pAD patients (conversion time, 36 ± 12 months) and 33 sMCI patients from the Alzheimer's Disease Neuroimaging Initiative cohort. Medial temporal atrophy was measured by manual, semi-automated, and automated hippocampal volumetry; cortical hypometabolism was measured using several indices of AD-related hypometabolism pattern; and cerebrospinal fluid markers were amyloid β (Aβ)42 and total tau protein concentrations. For each biomarker, sensitivity for pAD, specificity for sMCI, and diagnostic accuracy were computed.
Sensitivity to predict MCI conversion to AD in the Alzheimer's Disease Neuroimaging Initiative and Translational Outpatient Memory Clinic cohorts was 79% and 94% based on Aβ42, 46% and 28% based on hippocampal volumes, 33% to 66% and 56% to 78% based on different hypometabolism indices, and 46% and 61% based on total tau levels, respectively. Specificity to exclude sMCI was 27% and 50% based on Aβ42, 76% and 94% based on hippocampal volumes, 58% to 67% and 55% to 83% based on different hypometabolism indices, and 61% and 83% based on total tau levels, respectively.
Current findings suggest that Aβ42 concentrations and hippocampal volumes may be used in combination to best identify pAD.
利用来自不同临床系列的数据来比较个体生物标志物预测轻度认知障碍（MCI）向阿尔茨海默病（AD）进展的敏感性和特异性。
评估了来自转化门诊记忆诊所队列的 18 名有前驱 AD（pAD；转换时间为 26±12 个月）和 18 名稳定 MCI（sMCI）患者的内侧颞叶萎缩、皮质代谢减退和脑脊液生物标志物，以及来自阿尔茨海默病神经影像学倡议队列的 24 名 pAD 患者（转换时间为 36±12 个月）和 33 名 sMCI 患者。内侧颞叶萎缩通过手动、半自动和自动海马体积测量来测量；皮质代谢减退使用几种 AD 相关代谢减退模式的指数来测量；脑脊液标志物为 Aβ42 和总 tau 蛋白浓度。对于每种生物标志物，计算了对 pAD 的敏感性、对 sMCI 的特异性和诊断准确性。
基于 Aβ42，在阿尔茨海默病神经影像学倡议和转化门诊记忆诊所队列中，预测 MCI 向 AD 转化的敏感性分别为 79%和 94%，基于海马体积的敏感性分别为 46%和 28%，基于不同代谢减退指数的敏感性分别为 33%至 66%和 56%至 78%，基于总 tau 水平的敏感性分别为 46%和 61%。基于 Aβ42，排除 sMCI 的特异性分别为 27%和 50%，基于海马体积的特异性分别为 76%和 94%，基于不同代谢减退指数的特异性分别为 58%至 67%和 55%至 83%，基于总 tau 水平的特异性分别为 61%和 83%。
目前的研究结果表明，Aβ42 浓度和海马体积可以结合使用，以最佳地识别 pAD。
