Tsiskaridze A, Shakarishvili R, Janelidze M, Vashadze T, Chikhladze M
Dementia Research Group, Sarajishvili Institute of Neurology, Tbilisi, Georgia.
Funct Neurol. 1998 Jan-Mar;13(1):17-25.
To reveal cognitive correlates of leukoaraiosis (LA) in the early stages of Alzheimer's disease (AD) and to exclude confounding effects of aging, brain atrophy, education and dementive illness on cognition, we carefully selected a sample of 37 probable AD patients (NINCDS-ADRDA criteria, Hachinski ischemic score < 5) with similar indices of age, educational level, degree of brain atrophy and dementia severity (CDR 0.5, CDR 1 and MMSE score no lower than 20), and compared the results of neuropsychological testing of patients with and without LA. All patients underwent magnetic resonance imaging. LA was detected in 17 out of 37 cases. There were no significant differences between subjects with and without LA (Student's t-test, p>0.05) in tests that evaluate language, verbal intelligence and visuospatial functions, while the patients with LA showed poorer performance (p<0.05) in the tests evaluating verbal memory, attention/concentration and executive functions. The results obtained suggest that the patients with LA in the early stages of AD revealed dorsolateral prefrontal dysfunction syndrome due to disconnection of cortico-subcortical circuits. We found this syndrome to be more prenounced than it has been described in the non-demented elderly with LA. It may be that in patients suffering from degenerative illness, the brain has fewer compensatory reserves than in cases of "normal" aging, and it is more sensitive to ischemic damage caused by cerebral amyloid, arteriosclerotic or fibro-hyalinotic angiopathy. This typical neuropsychological syndrome is revealed only in the initial stage of AD in patients with LA. The follow-up progress of the atrophic-degenerative illness leads to overlapping of the specific neuropsychological syndrome by global cognitive impairment.
为揭示阿尔茨海默病（AD）早期白质疏松（LA）与认知的相关性，并排除衰老、脑萎缩、教育程度和痴呆性疾病对认知的混杂影响，我们精心挑选了37例可能患有AD的患者（符合NINCDS-ADRDA标准，Hachinski缺血评分<5），这些患者在年龄、教育水平、脑萎缩程度和痴呆严重程度（CDR 0.5、CDR 1且MMSE评分不低于20）等指标上相似，并比较了有LA和无LA患者的神经心理学测试结果。所有患者均接受了磁共振成像检查。37例患者中有17例检测到LA。在评估语言、言语智力和视觉空间功能的测试中，有LA和无LA的受试者之间无显著差异（Student t检验，p>0.05），而在评估言语记忆、注意力/集中力和执行功能的测试中，有LA的患者表现较差（p<0.05）。所得结果表明，AD早期有LA的患者因皮质-皮质下回路断开而出现背外侧前额叶功能障碍综合征。我们发现该综合征比在非痴呆老年人LA中所描述的更为明显。可能是在患有退行性疾病的患者中，大脑的代偿储备比“正常”衰老的情况要少，并且对由脑淀粉样蛋白、动脉硬化或纤维玻璃样变性血管病引起的缺血性损伤更敏感。这种典型的神经心理学综合征仅在AD早期有LA的患者中出现。萎缩性退行性疾病的后续进展会导致特定神经心理学综合征与整体认知障碍重叠。
