Division of Psychiatry, University College London, London, United Kingdom.
Princess Alexandra Hospital NHS Trust, Harlow, United Kingdom.
Dement Geriatr Cogn Disord. 2020;49(6):583-588. doi: 10.1159/000510951. Epub 2020 Nov 23.
Fifteen percent of people with mild cognitive impairment (MCI) will progress to dementia within 2 years. There is increasing focus on the evaluation of biomarkers which point towards the underlying pathology. This enables better prediction of clinical outcomes. Early diagnosis of the dementia subtype is crucial for appropriate management and accurate prognosis. The aim of this study was to compare MRI measures in stable mild cognitive impairment patients (stable-MCI), prodromal Alzheimer's disease (pro-AD), and prodromal dementia with Lewy bodies (pro-DLB).
Out of 1,814 patients assessed in Essex memory clinic between 2002 and 2017, 424 had MCI at baseline with follow-up data. All patients underwent comprehensive clinical and cognitive assessment at each assessment. MRI scans were acquired at patients' baseline assessment, corresponding to the time of initial MCI clinical diagnosis. Patients were grouped according to their diagnosis at the end of follow-up. All baseline scans were visually rated according to established rating scales for medial temporal atrophy (MTA), global cortical atrophy (GCA), and white matter lesions (WMLs).
MRI scans were available for 28 pro-DLB patients and were matched against 27 pro-AD and 28 stable-MCI patients for age, sex, and education. The mean follow-up duration was 34 months for the pro-AD group, 27 months for the pro-DLB group, and 21 months for the stable-MCI group. MTA scores were significantly greater in pro-AD patients compared to pro-DLB (p = 0.047) and stable-MCI patients (p = 0.012). There was no difference on GCA or WMLs between pro-AD, pro-DLB, and stable-MCI.
This study indicates that a simple visual rating of MTA at the stage of MCI already differs at a group level between patients that progress to AD, DLB, or continue to be stable-MCI. This could aid clinicians to differentiate between MCI patients who are likely to develop AD, versus those who might progress to DLB or remain stable.
15%的轻度认知障碍（MCI）患者在 2 年内会进展为痴呆症。目前越来越关注能够指向潜在病理的生物标志物的评估。这可以更好地预测临床结果。早期诊断痴呆亚型对于进行适当的管理和准确的预后至关重要。本研究旨在比较稳定的轻度认知障碍患者（稳定-MCI）、前驱期阿尔茨海默病（前驱 AD）和前驱期路易体痴呆（前驱 DLB）患者的 MRI 测量值。
在 2002 年至 2017 年间在埃塞克斯记忆诊所评估的 1814 名患者中，有 424 名患者在基线时有 MCI，且有随访数据。所有患者在每次评估时都接受了全面的临床和认知评估。MRI 扫描在患者的基线评估时采集，与初始 MCI 临床诊断时相对应。根据患者在随访结束时的诊断对患者进行分组。根据既定的内侧颞叶萎缩（MTA）、全脑皮质萎缩（GCA）和白质病变（WML）评分量表，对所有基线扫描进行了视觉评分。
共 28 名前驱 DLB 患者的 MRI 扫描可用，并与 27 名前驱 AD 和 28 名稳定-MCI 患者进行了年龄、性别和教育匹配。前驱 AD 组的平均随访时间为 34 个月，前驱 DLB 组为 27 个月，稳定-MCI 组为 21 个月。与前驱 DLB（p=0.047）和稳定-MCI（p=0.012）患者相比，前驱 AD 患者的 MTA 评分明显更高。在 GCA 或 WML 方面，前驱 AD、前驱 DLB 和稳定-MCI 之间没有差异。
这项研究表明，在 MCI 阶段，MTA 的简单视觉评分已经在进展为 AD、DLB 或继续保持稳定-MCI 的患者之间在组水平上存在差异。这有助于临床医生区分可能进展为 AD 的 MCI 患者，与可能进展为 DLB 或保持稳定的患者。
