美国宾利法尼亚大学的Daniel Weintraub博士近日在《神经学文献》(Archives of Neurology)上发表论文称,帕金森病患者的脑萎缩与其认知能力下降有关。
在对84名帕金森病患者进行研究后发现,认知能力正常的患者其大脑体积与健康者相近;而同认知能力正常的患者相比,有轻度认知障碍者其大脑海马区显着萎缩(P=0.001),而痴呆水平和认知障碍与海马区(P=0.004)和内侧额叶(P=0.003)的萎缩有相关性。
轻度认知障碍的帕金森病患者呈现出一种与认知正常的患者显着不同的脑萎缩,而与有严重认知障碍的患者相似。
帕金森病患者发生痴呆的累积发病率可高达80%,还有25%未发生痴呆的患者可达到轻度认知障碍的标准。而对帕金森性痴呆的生物标记研究发现,痴呆者最易发生萎缩的部位为顶颞叶和额叶前部皮质。
该研究的参与者包括84名帕金森病患者和23名正常人,分别对其进行MRI检查和神经心理测试。
痴呆量表2测试发现,61名帕金森病患者认知功能正常,12名有轻度认知障碍,11名有痴呆。霍普金斯语言学习能力测试发现认知功能正常的患者与轻度认知障碍者和痴呆者有显着差异,痴呆者的认知语言学习能力得分最低。
MRI结果显示,同认知功能正常者相比,痴呆和轻度认知障碍的帕金森病患者大脑海马区显着萎缩,而痴呆者和轻度认知障碍者无显着差异。痴呆者与认知功能正常者相比,其内侧颞叶显着萎缩。(生物谷bioon.com)
doi:10.1001/archneurol.2011.725
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Neurodegeneration Across Stages of Cognitive Decline in Parkinson Disease
Daniel Weintraub, MD; Jimit Doshi, MS; Deepthi Koka, MS; Christos Davatzikos, PhD; Andrew D. Siderowf, MD, MSCE; John E. Duda, MD; David A. Wolk, MD;Paul J. Moberg, PhD; Sharon X. Xie, PhD; Christopher M. Clark, MD.
Objective To assess regions and patterns of brain atrophy in patients with Parkinson disease (PD) with normal cognition (PD-NC), mild cognitive impairment (PD-MCI), and dementia-level cognitive deficits (PDD).
Design Images were quantified using a region-of-interest approach and voxel-based morphometry analysis. We used a high-dimensional pattern classification approach to delineate brain regions that collectively formed the Spatial Pattern of Abnormalities for Recognition of PDD.
Setting The Parkinson's Disease and Movement Disorders Center at the University of Pennsylvania.
Subjects Eighty-four PD patients (61 PD-NC, 12 PD-MCI, and 11 PDD) and 23 healthy control subjects (HCs) underwent magnetic resonance imaging of the brain.
Results The PD-NC patients did not demonstrate significant brain atrophy compared with HCs. Compared with PD-NC patients, PD-MCI patients had hippocampal atrophy (β = -0.37; P = .001), and PDD patients demonstrated hippocampal (β = -0.32; P = .004) and additional medial temporal lobe atrophy (β = -0.36;P = .003). The PD-MCI patients had a different pattern of atrophy compared with PD-NC patients (P = .04) and a similar pattern to that of PDD patients (P = .81), characterized by hippocampal, prefrontal cortex gray and white matter, occipital lobe gray and white matter, and parietal lobe white matter atrophy. In nondemented PD patients, there was a correlation between memory-encoding performance and hippocampal volume.
Conclusions Hippocampal atrophy is a biomarker of initial cognitive decline in PD, including impaired memory encoding and storage, suggesting heterogeneity in the neural substrate of memory impairment. Use of a pattern classification approach may allow identification of diffuse regions of cortical gray and white matter atrophy early in the course of cognitive decline.