Association Between Sleep Disturbances and Neuroimaging Biomarkers, Including White Matter Hyperintensities, Found

New research published in the May 10, 2023 issue of Neurology found an association between sleep disturbances, including obstructive sleep apnea (OSA), and neuroimaging biomarkers. Individuals with severe OSA were more likely to have evidence of an increased volume of white matter hyperintensities (WMH) and reduced axonal integrity compared with those with either mild or moderate OSA according to MRI scans. In addition, researchers found a link between sleep quality and neuroimaging biomarkers: participants who experienced less deep sleep also had increased WMH volume and reduced axonal integrity compared with others.

The study involved 140 participants from the population-based Mayo Clinic Study of Aging with OSA who were not diagnosed with dementia and who underwent 1 or more MRI scans and a polysomnography test conducted in a sleep laboratory. Sleep quality was measured by the amount of time participants spent in stage 3 sleep.

“More research is needed to determine whether sleep issues affect these brain biomarkers or vice versa,” according to study coauthor Diego Z. Carvalho, MD, MS, Mayo Clinic, Rochester, said. “We also need to look at whether strategies to improve sleep quality or treatment of sleep apnea can affect the trajectory of these biomarkers.” 

There are a number of limitations to this study, including the fact that sleep measurements were not captured for a full night of sleep. Participants’ sleep patterns were registered for the first few hours of sleep until they met the criteria of OSA diagnosis after which they received treatment consisting of continuous positive airway pressure (CPAP) for the remainder of the night.