Bu Lingguo, Huo Congcong, Xu Gongcheng, Liu Ying, Li Zengyong, Fan Yubo, Li Jianfeng
Key Laboratory of High Efficiency and Clean Mechanical Manufacture, School of Mechanical Engineering, Shandong University, Jinan, China.
Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, China.
Front Physiol. 2018 May 31;9:669. doi: 10.3389/fphys.2018.00669. eCollection 2018.
To reveal the physiological mechanism of the cognitive decline in subjects with hypertension, the functional connectivity (FC) was assessed by using the wavelet phase coherence (WPCO), and effective connectivity (EC) was assessed by using the coupling strength (CS) of near-infrared spectroscopy (NIRS) signals. NIRS signals were continuously recorded from the prefrontal cortex, sensorimotor cortex, and occipital lobes of 13 hypertensive patients (hypertension group, 70 ± 6.5 years old) and 16 elderly healthy subjects (control group, 71 ± 5.5 years old) in resting and standing periods. WPCO and CS were calculated in four frequency intervals: I, 0.6-2; II, 0.145-0.6; III, 0.052-0.145; and IV, 0.021-0.052 Hz. CS quantifies coupling amplitude. In comparison with the control group, the hypertension group showed significantly decreased ( < 0.05) WPCO and CS in intervals III and IV and in the resting and standing states. WPCO and CS were significantly decreased in the resting state compared with those in the standing state in the hypertension group ( < 0.05). Decreased WPCO and CS indicated a reduced network interaction, suggesting disturbed neurovascular coupling in subjects with hypertension. Compared with the control group, the hypertension group showed significantly lower Mini-Mental State Examination (MMSE) ( = 0.028) and Montreal Cognitive Assessment (MoCA) scores ( = 0.011). In the hypertension group, correlation analysis showed that WPCO and CS were significantly positively correlated with MMSE and MoCA scores, respectively. These findings may provide evidence of impaired cognitive function in hypertension and can enhance the understanding on neurovascular coupling.
为揭示高血压患者认知功能下降的生理机制，采用小波相位相干性（WPCO）评估功能连接性（FC），并通过近红外光谱（NIRS）信号的耦合强度（CS）评估有效连接性（EC）。在静息期和站立期，连续记录了13例高血压患者（高血压组，70±6.5岁）和16例老年健康受试者（对照组，71±5.5岁）前额叶皮质、感觉运动皮质和枕叶的NIRS信号。在四个频率区间计算WPCO和CS：区间I，0.6 - 2；区间II，0.145 - 0.6；区间III，0.052 - 0.145；区间IV，0.021 - 0.052 Hz。CS量化耦合幅度。与对照组相比，高血压组在区间III和IV以及静息和站立状态下的WPCO和CS显著降低（<0.05）。高血压组静息状态下的WPCO和CS与站立状态相比显著降低（<0.05）。WPCO和CS降低表明网络交互减少，提示高血压患者存在神经血管耦合紊乱。与对照组相比，高血压组的简易精神状态检查表（MMSE）得分（=0.028）和蒙特利尔认知评估（MoCA）得分（=0.011）显著更低。在高血压组中，相关性分析表明WPCO和CS分别与MMSE和MoCA得分显著正相关。这些发现可能为高血压患者认知功能受损提供证据，并可增强对神经血管耦合的理解。
