In a new study conducted at the University of Chicago’s Medical Center, researchers scanned the brains of children between 7 and 11 years old who have moderate or severe obstructive sleep apnea (OSA) and found that, if untreated, it can lead to widespread brain damage.

In the study published in Scientific Reports, researchers evaluated 16 children with OSA and nine healthy children who did not have apnea. They were assessed overnight in the pediatric sleep laboratory. The participants underwent neuro-cognitive testing and non-invasive MRI. Researchers also compared the children with OSA to 191 MRI scans of children who were part of an existing pediatric-MRI database.

"The images of gray matter changes are striking," said one of the study's senior authors, Leila Kheirandish-Gozal, MD, director of pediatric clinical sleep research at the University of Chicago, in a statement. "We do not yet have a precise guide to correlate loss of gray matter with specific cognitive deficits, but there is clear evidence of widespread neuronal damage or loss compared to the general population."

Data suggests there were reductions in the volume of gray matter in the frontal cortices, prefrontal cortices, temporal lobe, parietal cortices and the brainstem.

"MRI scans give us a bird's-eye view of the apnea-related difference in volume of various parts of the brain, but they don't tell us, at the cellular level, what happened to the affected neurons or when," said co-author David Gozal, MD, professor of pediatrics at the University of Chicago. "The scans don't have the resolution to determine whether brain cells have shrunk or been lost completely," he added. "We can't tell exactly when the damage occurred. But previous studies from our group showed that we can connect the severity of the disease with the extent of the cognitive deficits, when such deficits are detectable."