目的:通过评估接受血液透析的终末期肾病(ESRD)患者与健康对照参与者的脑灌注与脑连通性之间的关系来评估神经血管偶联(NVC)的变化。通过探索与患者认知障碍相关的NVC异常的大脑区域,我们旨在为潜在的预防和治疗干预措施提供新的见解.
方法:共有45名患者和40名匹配的健康对照者被前瞻性纳入本研究。蒙特利尔认知评估(MoCA)用于评估认知功能。动脉自旋标记(ASL)用于计算脑血流量(CBF),基于图论的静息态功能磁共振成像(rs-fMRI)结果分析用于计算脑网络拓扑参数(节点间中心性[BC],节点效率[Ne],和节点度中心性[DC])。三种NVC生物标志物(CBF-BC,CBF-Ne,和CBF-DC系数)在整个大脑水平和3个NVC生物标志物(CBF/BC,CBF/Ne,和CBF/DC比率)在局部大脑区域水平上用于评估NVC。Mann-WhitneyU检验用于比较NVC参数的组间差异。采用Spearman相关分析评价NVC功能失调模式与NVC功能失调模式之间的关系。认知障碍,和临床特征多重比较使用体素错误发现率(FDR)方法进行校正(p<0.05)。
结果:与健康对照相比,患者的CBF-Ne(p=.023)和CBF-BC(p=.035)的整体耦合系数显着降低。在33个脑区的患者中,局部脑区水平的偶联率明显更高(所有p值<0.05)。耦合比单独变化或伴随CBF变化,节点属性,或同时识别CBF和节点属性。在患者中,许多脑区的耦合度与MoCA评分呈负相关,包括左背外侧额上回,双侧正中扣带和副带回,和右顶叶上回.甚至在调整血红蛋白和血细胞比容水平之后,相关性仍然存在。
结论:NVC紊乱可能是透析患者认知功能损害的机制之一。
OBJECTIVE: To assess changes in neurovascular coupling (NVC) by evaluating the relationship between cerebral perfusion and brain connectivity in patients with end-stage renal disease (ESRD) undergoing hemodialysis versus in healthy control participants. And by exploring brain regions with abnormal NVC associated with cognitive deficits in patients, we aim to provide new insights into potential preventive and therapeutic interventions.
METHODS: A total of 45 patients and 40 matched healthy controls were prospectively enrolled in our
study. Montreal Cognitive Assessment (MoCA) was used to assess cognitive function. Arterial spin labeling (ASL) was used to calculate cerebral blood flow (CBF), and graph theory-based analysis of results from resting-state functional magnetic resonance imaging (rs-fMRI) was used to calculate brain network topological parameters (node betweenness centrality [BC], node efficiency [Ne], and node degree centrality [DC]). Three NVC biomarkers (CBF-BC, CBF-Ne, and CBF-DC coefficients) at the whole brain level and 3 NVC biomarkers (CBF/BC, CBF/Ne, and CBF/DC ratios) at the local brain region level were used to assess NVC. Mann-Whitney U tests were used to compare the intergroup differences in NVC parameters. Spearman\'s correlation analysis was used to evaluate the relationship among NVC dysfunctional pattern, cognitive impairment, and clinical characteristics multiple comparisons were corrected using a voxel-wise false-discovery rate (FDR) method (p < .05).
RESULTS: Patients showed significantly reduced global coupling coefficients for CBF-Ne (p = .023) and CBF-BC (p = .035) compared to healthy controls. Coupling ratios at the local brain region level were significantly higher in patients in 33 brain regions (all p values < .05). Coupling ratio changes alone or accompanied by changes in CBF, node properties, or both CBF and node properties were identified. In patients, negative correlations were seen between coupling ratios and MoCA scores in many brain regions, including the left dorsolateral superior frontal gyrus, the bilateral median cingulate and paracingulate gyri, and the right superior parietal gyrus. The correlations remained even after adjusting for hemoglobin and hematocrit levels.
CONCLUSIONS: Disrupted NVC may be one mechanism underlying cognitive impairment in dialysis patients.