Activation of the spontaneous brain and functional connectivity in patients with and without cognition impairment in coronary heart disease

Abstract Background/Aims: Patients with coronary heart disease (CHD) have a higher risk of developing cognitive impairment (CI) and dementia. The purpose of this study was to investigate changes in spontaneous brain activity and functional connectivity (FC) of resting-state functional magnetic resonance imaging (rs-fMRI) in patients with and without CI in CHD patients. This will allow early diagnosis of cognitive impairment by detecting the relationships between these parameters and CI. Materials and methods: A total of 46 CHD patients with cognitive impairment (CHD-CI), 40 CHD patients with normal cognition (CHD-NC), and 43 healthy controls (HCs) participated in the study. Each subject underwent an rs-fMRI examination and neuropsychological assessment. CHD-CI and CHD-NC patients, as well as healthy controls, were compared for regional homogeneity (ReHo) and seed-based FC. Further investigation was performed on the relationship between rs-fMRI data and cognitive performance. Results: The bilateral SFGmed revealed a decrease in ReHo values in both CHD-CI and CHD-NC patients. The CHD-CI group illustrated decreased FC between the bilateral SFGmed and left MGT/left IGT. Furthermore, the ReHo and FC values were related to cognitive test score in CHD patients with CI. The duration of the CHD and the cognitive test score correlated positively with decreased ReHo/FC values in CHD-CI patients. Conclusion: In our combined analyses, we found decreased spontaneous activity and FC primarily within the default mode network (DMN), which was correlated with specific cognitive impairment and a longer duration of impairment. As a result, this study sheds light on the neurophysiological mechanisms that contribute to cognitive impairment caused by CHD and may serve as a guideline for future clinical diagnoses.