Juckel Georg, Clotz Frauke, Frodl Thomas, Kawohl Wolfram, Hampel Harald, Pogarell Oliver, Hegerl Ulrich
Department of Psychiatry, Ruhr-University Bochum, Germany.
J Clin Neurophysiol. 2008 Jun;25(3):147-52. doi: 10.1097/WNP.0b013e3181727c95.
Early diagnosis of Alzheimers disease (AD) would be of great clinical value. Auditory event-related P300 mainly generated in temporoparietal regions is related to the pathophysiology of AD. A former study revealed that reliable separation of P300 subcomponents by dipole source analysis increased sensitivity (86.7%) and specificity (76.7%) in correctly detecting AD patients from healthy subjects. Aim of the present study was to replicate this interesting finding on a different sample. Auditory event-related P300 was recorded in unmedicated patients with mild to moderate AD and age- and sex-matched healthy volunteers. The subcomponents of the P300, P3a and P3b, were determined by dipole source analysis (Brain Electric Source Analysis program). As in the first study, AD patients were again characterized by a diminished P3b amplitude and longer P3a latency and reaction time. Using these three parameters, sensitivity was 81.3% to detect patients with AD from healthy controls with a specificity of 83.3%. This successful replication of the first study suggests that recording and determining P300 subcomponents together with other putative neurobiological markers may be useful to enhance the individual diagnostic accuracy in AD at an early stage.
阿尔茨海默病（AD）的早期诊断具有重要的临床价值。主要在颞顶叶区域产生的听觉事件相关P300与AD的病理生理学有关。先前的一项研究表明，通过偶极子源分析对P300子成分进行可靠分离，在从健康受试者中正确检测出AD患者方面，灵敏度提高到了86.7%，特异性提高到了76.7%。本研究的目的是在不同样本上重复这一有趣的发现。对未用药的轻度至中度AD患者以及年龄和性别匹配的健康志愿者记录听觉事件相关P300。通过偶极子源分析（脑电源分析程序）确定P300的子成分P3a和P3b。与第一项研究一样，AD患者的特征依然是P3b波幅减小、P3a潜伏期和反应时间延长。利用这三个参数，从健康对照中检测出AD患者的灵敏度为81.3%，特异性为83.3%。第一项研究的这一成功复现表明，记录和确定P300子成分以及其他假定的神经生物学标志物，可能有助于提高AD早期阶段的个体诊断准确性。
