Huang Chaorui, Wahlund Lars-Olof, Almkvist Ove, Elehu Dagmawi, Svensson Leif, Jonsson Tomas, Winblad Bengt, Julin Per
Department of Clinical Neuroscience, Occupational Therapy and Elderly Care Research, Division of Geriatric Medicine, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden.
Neuroimage. 2003 Jul;19(3):1137-44. doi: 10.1016/s1053-8119(03)00168-x.
This study aimed to explore the heterogeneity of mild cognitive impairment (MCI) and detect differences in regional cerebral blood flow (rCBF) and cognitive function between progressive mild cognitive impairment (PMCI) and stable mild cognitive impairment (SMCI) in order to identify specific changes useful for early diagnosis of dementia. SPECT was performed in 82 MCI subjects and 20 controls using Tc-99m hexamethylpropyleneamine oxime. Cognitive functions were tested in five domains which included episodic memory, semantic memory, visuospatial function, attention, and general cognitive function. After the initial examination, MCI subjects were clinically followed for an average of 2 years. Twenty-eight subjects progressed to dementia and were defined as PMCI at baseline and 54 subjects remained stable and were defined as SMCI at baseline. The baseline rCBF and cognitive function of PMCI, SMCI, and controls were compared. PMCI had decreased relative rCBF in the parietal lobes and increased relative rCBF in prefrontal cortex compared to SMCI and controls at baseline. The cognitive function of PMCI was more severely impaired compared to SMCI with respect to episodic memory and visuospatial and general cognitive function. Both SPECT and neuropsychological tests had moderate discriminant function between PMCI and SMCI at baseline with the area under the receiver operating characteristic (ROC) curve at 75-77%. The combination of these two methods improved the diagnostic accuracy with the area under the ROC curve at 82-84%. Semantic memory and attention were negatively correlated with left prefrontal relative rCBF among the study population. The results show that the clinical heterogeneity of MCI is reflected in different patterns of psychological and CBF changes. Combined SPECT investigation and neuropsychological testing might predict the future development of dementia in patients with MCI.
本研究旨在探讨轻度认知障碍（MCI）的异质性，检测进展性轻度认知障碍（PMCI）和稳定性轻度认知障碍（SMCI）之间的局部脑血流量（rCBF）和认知功能差异，以确定有助于早期诊断痴呆的特定变化。使用锝-99m六甲基丙烯胺肟对82例MCI受试者和20例对照者进行单光子发射计算机断层扫描（SPECT）。在五个领域对认知功能进行了测试，包括情景记忆、语义记忆、视觉空间功能、注意力和一般认知功能。在初次检查后，对MCI受试者进行了平均2年的临床随访。28名受试者进展为痴呆，在基线时被定义为PMCI，54名受试者保持稳定，在基线时被定义为SMCI。比较了PMCI、SMCI和对照者的基线rCBF和认知功能。与SMCI和对照者相比，PMCI在基线时顶叶相对rCBF降低，前额叶皮质相对rCBF增加。在情景记忆、视觉空间和一般认知功能方面，PMCI的认知功能比SMCI受损更严重。在基线时，SPECT和神经心理学测试在PMCI和SMCI之间均具有中等判别功能，受试者工作特征（ROC）曲线下面积为75%-77%。这两种方法的联合应用提高了诊断准确性，ROC曲线下面积为82%-84%。在研究人群中，语义记忆和注意力与左前额叶相对rCBF呈负相关。结果表明，MCI的临床异质性体现在心理和CBF变化的不同模式中。联合SPECT检查和神经心理学测试可能预测MCI患者痴呆的未来发展。
