事件相关电位在阿尔茨海默病与轻度认知障碍中的应用

Application of event-related potential in Alzheimer's disease and mild cognitive impairment

阿尔茨海默病(Alzheimer's disease,AD)是危害老人健康的重大疾病之一,轻度认知障碍(mild cognitive impairment,MCI)是AD的临床早期阶段,两者的临床诊断均存在滞后性,亟需一种客观可靠的辅助诊断方法,为AD和MCI提供早期诊断及鉴别指标,预知个体患AD或MCI转变为AD的概率,从而降低AD总体发病率,为国家和社会减轻医疗和经济负担。事件相关电位(event-related potential,ERP)在AD及MCI中广泛应用,毫秒级别的分辨率能够真实反映患者认知加工的时间进程及认知功能的损伤程度。本研究探讨不同时间进程的ERPs成分在健康老人、MCI和AD患者波幅和潜伏期的差异以及与其认知功能损伤的相关性。早期感觉N170和P200在区分健康老人和MCI或鉴别MCI和AD中具备较高的灵敏度和特异性,后期知觉相关ERPs在鉴别健康老人和MCI/AD上亦表现出较高的灵敏度和特异性。MCI和AD的ERPs差异可能与其病因、疾病发展程度以及脑部损伤的部位有关,具体脑机制以及结论仍有待于进一步探究,也将是今后的研究重点。随着研究的进展,其具体ERP表现与脑部损伤机制以及与其认知功能损伤的关系也会更加明确清晰,相信ERP在临床上的应用会给AD及其临床早期MCI带来更多的益处。

Alzheimer's disease(AD)is one of the major diseases that harmful to healthy elderly,and mild cognitive impairment(MCI)is the early clinical stage of AD.There is a lag in the clinical diagnosis of both diseases.An objective and reliable auxiliary diagnostic method is urgently needed to provide early diagnosis and differential indicators for AD and MCI,to predict the probability of individuals suffering from AD and MCI transforming into AD,and to reduce the overall incidence of AD and reduce the huge medical and economic burden for the country and society.Event-related potential is widely used in AD and MCI,and the resolution at the millisecond level can truly reflect the time course of cognitive processing and the degree of impairment of cognitive function in patients.In this study,we investigated the differences in the amplitude and latency of ERP components in healthy elderly,MCI and AD patients,and the correlation between ERP components and cognitive impairment.Early N170 and P200 showed high sensitivity and specificity in differentiating MCI from healthy elderly or MCI from AD.The late perception-related ERPs also showed high sensitivity and specificity in differentiating healthy elderly from MCI/AD.The differences in ERPs between MCI and AD may be related to the etiology,the degree of disease progression and the site of brain damage.The specific brain mechanism still need to be further explored and will be the focus of future research.With the progress of the research,the relationship between the specific ERP manifestations and the mechanism of brain injury as well as the impairment of cognitive function will be more clear.It is believed that the application of ERP in clinical will bring more benefits to AD and its early clinical MCI.