Aberrant Functional Connectivity Of Executive Control Network And Frontoparietal Network In Type 2 Diabetes Patients

Objective We aimed to investigate the integrity of a executive control network(ECN)、 frontoparietal network (FPN) in type 2 diabetic patients by using independent component analysis(ICA), and to explore the relationship between network abnormalities, neurocognitive performance and glycaemic indices.Methods A total of 24 patients were recruited by advertisements and met the latest criteria of T2DM. Healthy controls (n=25) were also recruited through advertisements and were matched with T2DM patients with respect to age, sex and education. Biometric measurement was performed at 8:00 a.m. All participants performed an extensive neurocognitive examination covering several cognitive domains. MRI data were acquired using a Siemens Verio 3.0-T system. fMRI data preprocessing was carried out using SPM8. ICA was conducted using the Informix algorithm in the Group ICA of fMRI Toolbox (GIFT) software. Statistical analysis was conducted using REST-Statistical Analysis and the SPSS software (version 19.0).Results1. Participant information One participant was excluded because of head movement. So a total of 48 participants (23 T2DM patients and 25 healthy controls) were included in the final data analysis. Comparing the diabetic and control groups, no significant differences were observed in terms of the total cholesterol, WMH loads and lacunar infarcts, and body mass index (BMI). However, patients performed significantly worse on the MoCA, TMT-B, CFT, CFT-delayed recall and DST tests, which mainly involved cognitive domains of executive function, processing speed and spatial episodic memory.2. Spatial pattern of ECN. FPN Among the 30 components estimated during the data processing, three components were identified as the ECN,1-FPN and r-FPN. Compared with previous studies, the patterns are consistent.3. Group differences in ECN、FPN ECN:Compared with the healthy controls, patients showed increased FC in the right insula and left parietal cortex, while decreased FC in the left parietal lobe, cingulate gyrus, right frontal lobe. r-FPN:Compared with the healthy controls, patients showed increased FC in the right inferior frontal gyrus and middle frontal gyrus, decreased FC in the right postcentral gyrus. 1-FPN:Compared with the healthy controls, patients showed decreased FC in the left parietal lobe.4. Correlation analysis The decreased connectivity in the right frontal lobe was significantly correlated with the insulin resistance level (P=0.046, r=-0.420). FC strength in the ECN and FPN was negative correlated with the neurocognitive performance.Conclusion1. Comparing to the control group, T2DM group manifests cognitive impairments of executive function, processing speed and spatial episodic memory.2. Using the ICA method, we demonstrated a disrupted pattern of resting-state ECN and FPN in T2DM patients.3. The disrupted pattern of resting-state ECN was associated with IR in T2DM patients.