Functional-structural decoupling in visual network is associated with cognitive decline in patients with type 2 diabetes mellitus: Evidence from a multimodal MRI analysis

Abstract

Abstract Visual network (VN) related alterations is suggested to be one potential mechanism in type 2 diabetes mellitus (T2DM) associated mild cognitive impairment (MCI) and functional-structural coupling is a useful method to explore cerebral subtle changes. However, it is still unclear about the relationship between functional-structural decoupling in VN evidences derived from functional magnetic resonance imaging and cognitive impairment in T2DM. Thirty T2DM patients without MCI and twenty-nine healthy controls were prospectively enrolled. Visual components (VC) were estimated by independent component analysis (ICA). Degree centrality (DC), amplitude of low frequency fluctuation (ALFF) and fractional anisotropy (FA) were constructed to reflect functional and structural characteristics in these VCs respectively. Functional-structural coupling coefficients were further evaluated using combined FA and DC or ALFF. Partial correlations were performed between neuroimaging indicators and neuropsychological scores and clinical variables. Three VCs were selected using group ICA. Deteriorated DC, ALFF and DC-FA coefficients in VC1 were observed in T2DM group compared with control subjects, while FA and ALFF-FA coefficients in three VCs were no significant differences between two groups. In T2DM group, DC in VC1 positively correlated with 2 subitems of the California Verbal Learning Test, including Trial 4 and Total trial 1–5. The impaired DC-FA coefficients in VC1 markedly affected the Total perseverative responses % of the Wisconsin Card Sorting Test. These findings indicate that DC and DC-FA coefficients in VN may be potential imaging biomarkers for revealing early cognitive deficits of different dimensions in T2DM.