Altered dynamic brain functional connectivity in patients with white matter hyperintensities: a prospective case-control study

Abstract Background White matter hyperintensities (WMHs) are commonly observed in older adults and are associated with cognitive impairment. Although resting-state functional magnetic resonance imaging studies have explored the mechanisms of cognitive impairment in patients with WMHs, knowledge about the role of dynamic functional connectivity (dFC) is limited in such patients. Our aim is to explore whether the dFC consists in such patients and associates with cognitive impairment. Methods We included 36 healthy controls (HCs) and 104 patients with mild (n = 39), moderate n = 37), and severe (n = 28) WMHs. Comprehensive neuropsychological scales were used to assess the cognitive functions. The sliding window approach was used to generate dFC matrices, and graph theory methods were applied to calculate the variability of the network topological properties. Relationships between cognitive functions and abnormal dFC were evaluated by Pearson’s correlation. Results Patients with WMHs and HCs showed no significant difference in small-world properties. However, there were significant differences in variability of nodal properties between the four groups, which were located within the default mode network (DMN) and cognitive control network (CCN). Correlation analysis revealed that, as the temporal variability of the nodal cluster coefficient increased in the left SMG, the TMT-A time and the AVLT-study score decreased in patients with WMHs. Moreover, as the nodal efficiency of the left Rolandic operculum increased, the MoCA score, the TMT-A and the TMT-B time increased in patients with WMHs. Conclusions Our results indicate that dynamic functional connectivity consists in patients with WMHs and associate with executive and memory function.