Tang Xue, Wang Luoyu, Feng Qi, Hu Hanjun, Zhu Yidi, Liao Zhengluan, Ding Zhongxiang, Xu Xiufang
School of Medical Imaging, Hangzhou Medical College, Hangzhou, China.
School of Biomedical Engineering, Shanghai Tech University, Shanghai, China.
Sci Rep. 2025 Jan 2;15(1):363. doi: 10.1038/s41598-024-82769-x.
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by memory impairment and cognitive decline, ultimately culminating in dementia. This study aims to evaluate cerebrovascular reactivity (CVR) and functional connectivity (FC) in patients with AD and mild cognitive impairment (MCI) using resting-state functional magnetic resonance imaging (rs-fMRI), bypassing the requirement for hypercapnia. The study cohort comprised 53 AD patients, 38 MCI patients, and 39 normal control (NC) subjects. CVR is derived by extracting signals within specific frequency bands of rs-fMRI. This study compares the differences in CVR and FC among the three groups, using the brain regions with CVR differences as region of interest (ROI) for FC analysis. The correlation between CVR and FC and cognitive scale score was discussed. Compared with NC subjects, AD patients exhibited a decrease in CVR in the PCUN.L, whereas MCI patients showed an increase in CVR in the PCUN.R. With PCUN.L as ROI, FC in PCUN.R decreased in AD patients, and FC in SFGmed.R and other brain regions increased in MCI patients compared with NC subjects. The results of the correlation analysis indicate that CVR in all patients, as well as FC with the PCUN.L as the ROI to the PCUN.R and SFGmed.R, show positive correlations with MMSE and MoCA scores. These results suggest that there are significant differences between CVR and FC with CVR differential brain regions as ROI among the AD, MCI, and NC groups, which may help to explain the hemodynamic mechanism. CVR obtained with rs-fMRI may be a potential biomarker for assessing cognitive impairment.
阿尔茨海默病（AD）是一种进行性神经退行性疾病，其特征为记忆障碍和认知衰退，最终发展为痴呆。本研究旨在使用静息态功能磁共振成像（rs-fMRI）评估AD和轻度认知障碍（MCI）患者的脑血管反应性（CVR）和功能连接（FC），无需高碳酸血症激发试验。研究队列包括53例AD患者、38例MCI患者和39名正常对照（NC）受试者。通过提取rs-fMRI特定频段内的信号来推导CVR。本研究比较三组之间CVR和FC的差异，将存在CVR差异的脑区作为感兴趣区（ROI）进行FC分析。探讨了CVR与FC以及认知量表评分之间的相关性。与NC受试者相比，AD患者左侧楔前叶（PCUN.L）的CVR降低，而MCI患者右侧楔前叶（PCUN.R）的CVR升高。以PCUN.L为ROI，AD患者右侧楔前叶的FC降低，与NC受试者相比，MCI患者右侧额中回（SFGmed.R）及其他脑区的FC升高。相关性分析结果表明，所有患者的CVR以及以PCUN.L为ROI与PCUN.R和SFGmed.R之间的FC均与简易精神状态检查表（MMSE）和蒙特利尔认知评估量表（MoCA）评分呈正相关。这些结果表明，以CVR差异脑区为ROI的CVR和FC在AD、MCI和NC组之间存在显著差异，这可能有助于解释血流动力学机制。通过rs-fMRI获得的CVR可能是评估认知障碍的潜在生物标志物。
