Disrupted small world topology and modular organisation of functional networks in late-life depression with and without amnestic mild cognitive impairment

作者：Li Wenjun; Ward B Douglas; Liu Xiaolin; Chen Gang; Jones Jennifer L; Antuono Piero G; Li Shi Jiang; Goveas Joseph S^*

来源：Journal of Neurology Neurosurgery and Psychiatry, 2015, 86(10): 1097-1105.

DOI：10.1136/jnnp-2014-309180

Background The topological architecture of the whole-brain functional networks in those with and without late-life depression (LLD) and amnestic mild cognitive impairment (aMCI) are unknown.
Aims To investigate the differences in the small-world measures and the modular community structure of the functional networks between patients with LLD and aMCI when occurring alone or in combination and cognitively healthy non-depressed controls.
Methods 79 elderly participants (LLD (n=23), aMCI (n=18), comorbid LLD and aMCI (n=13), and controls (n=25)) completed neuropsychiatric assessments. Graph theoretical methods were employed on resting-state functional connectivity MRI data.
Results LLD and aMCI comorbidity was associated with the greatest disruptions in functional integration measures (decreased global efficiency and increased path length); both LLD groups showed abnormal functional segregation (reduced local efficiency). The modular network organisation was most variable in the comorbid group, followed by patients with LLD-only. Decreased mean global, local and nodal efficiency metrics were associated with greater depressive symptom severity but not memory performance.
Conclusions Considering the whole brain as a complex network may provide unique insights on the neurobiological underpinnings of LLD with and without cognitive impairment.

• 出版日期2015-10