Aberrant brain functional connectome in patients with obstructive sleep apnea

Area of Science:

• Neuroscience
• Medical Imaging
• Systems Biology

Background:

• Obstructive sleep apnea (OSA) is linked to cognitive deficits.
• The brain's functional connectome topology in OSA patients remains largely unexplored.
• Abnormal spontaneous regional brain activity is common in OSA.

Purpose of the Study:

• To investigate the functional brain connectome's topological properties in OSA patients using graph theory.
• To analyze functional connectivity (FC) alterations in the OSA brain connectome.
• To explore the relationship between network topology and clinical variables in OSA.

Main Methods:

• Resting-state functional magnetic resonance imaging (rs-fMRI) was used for 45 male OSA patients and 45 male good sleepers (GSs).
• Functional brain connectomes were constructed using the Automated Anatomical Labeling (AAL) atlas.
• Graph theory methods characterized network topology and FC, with correlations to clinical data.

Main Results:

• OSA patients displayed altered network topology, including decreased global efficiency (Eglob) and increased path length (Lp).
• Abnormal nodal centralities were observed in default-mode (DMN), salience (SN), and central executive networks (CEN).
• Disrupted FC between DMN, SN, and CEN correlated with global network metrics and clinical scores (ESS, MoCA, oxygen desaturation).

Conclusions:

• OSA functional connectomes exhibit impaired integration and segregation, with DMN, SN, and CEN disconnections.
• Aberrant topological attributes and FC disruptions are associated with cognitive impairments in OSA.
• These topological abnormalities may serve as potential biomarkers for cognitive deficits in OSA patients.