Functional Segregation-Integration Preference Configures the Cognitive Decline Against Cerebral Small Vessel Disease:...

Cerebral small vessel disease (CSVD) is highly prevalent in elder individuals, and its variable cognitive outcomes indicate some cognitive reserve mechanisms. Contribution from functional network features is still unclear. Here we explore how functional segregation-integration preference influences the cognitive changes against CSVD.

A total of, 271 CSVD patients were included, all underwent MRI scans including routine and resting-state functional MRI (rs-fMRI). Hierarchical balance index (H_B) was obtained from the rs-fMRI connectivity using eigenmode-based approach. Individuals were classified into segregated and integrated groups according to negative and positive H_B. A composite CSVD lesion score was calculated from imaging findings. Global and five specific cognitive functions were assessed.

Hierarchical regression analysis revealed negative contribution from lesion load to global and all cognitive domains (β = -0.22~-0.35, ∆R² = 0.046~0.112, all p < 0.001). Inclusion of H_B did not show significant contribution (all p > 0.05), but interaction between H_B and lesion score was significantly associated with global (β = -0.27, ∆R² = 0.013, p = 0.034) and execution score (β = -0.34, ∆R² = 0.023, p = 0.002). Integrated patients show significant better global cognitive (23.9 ± 3.9 vs. 25.5 ± 3.1, p = 0.044) and executive ability (0.235 ± 0.678 vs. 0.535 ± 0.688, p = 0.049) at mild damage stage, visuospatial (-0.001 ± 0.804 vs. 0.379 ± 0.249, p = 0.034) and language ability (-0.133 ± 0.849 vs. 0.218 ± 0.704, p = 0.037) at moderate damage stage. Cross-overs of cognitive scores were observed. Significant better execution (-0.277 ± 0.717 vs. -0.675 ± 0.883, p = 0.027) was found in severe damage stage for segregated patients.

Thus, we concluded that integrated network contributes to cognitive resilience in mild and moderate but not in severe damage stages.