Decreased Regional Cerebral Perfusion in Moderate-Severe Obstructive Sleep Apnoea during Wakefulness

Area of Science:

• Neuroimaging
• Sleep Medicine
• Neurology

Background:

• Obstructive sleep apnea (OSA) is a prevalent condition affecting sleep and potentially brain health.
• Previous research suggests structural brain changes in severe OSA, but functional changes during wakefulness are less understood.

Purpose of the Study:

• To investigate differences in gray matter volume, concentration, and cerebral perfusion in individuals with untreated obstructive sleep apnea (OSA) compared to controls.
• To determine if these changes are detectable during wakefulness.

Main Methods:

• Utilized voxel-based morphometry for gray matter analysis and arterial spin labeling perfusion imaging for cerebral blood flow assessment.
• Included 19 participants with untreated OSA and 19 healthy controls, all scanned using 3-T MRI.

Main Results:

• No significant differences in gray matter volume or concentration were found between OSA patients and controls.
• Individuals with moderate-to-severe OSA (n=8) exhibited reduced cerebral perfusion in several brain regions, including the anterior cingulate cortex and hippocampus, compared to controls.
• No perfusion differences were observed in individuals with mild OSA (n=11).

Conclusions:

• Moderate-to-severe OSA is associated with decreased regional cerebral perfusion during wakefulness.
• These perfusion deficits occur in brain areas previously shown to have reduced gray matter volume in severe OSA.
• Hypothesize that altered cerebral perfusion may precede and potentially underlie future structural brain changes in OSA.