WEDNESDAY, Feb. 3 (HealthDay News) -- People with severe obstructive sleep apnea have reduced concentrations of gray matter in multiple areas of the brain, new research shows.

Gray matter refers to the brain's cerebral cortex, where the majority of information processing takes place. These changes in brain structure may help explain the memory, cardiovascular and other problems experienced by people with obstructive sleep apnea (OSA), the study authors explained in a news release from the American Academy of Sleep Medicine.

The findings also show the importance of diagnosing and treating the condition, according to the South Korean researchers.

"Poor sleep quality and progressive brain damage induced by OSA could be responsible for poor memory, emotional problems, decreased cognitive functioning and increased cardiovascular disturbances," principal investigator Dr. Seung Bong Hong, a professor of neurology at the Samsung Medical Center, Sungkyunkwan University School of Medicine, said in the news release. "The use of continuous positive airway pressure therapy could stop further progression of brain damage in patients with severe OSA."

The study included 36 men with OSA, average age 45, and 31 age-matched healthy men. While the OSA patients had reduced concentrations of gray matter, they had no significant changes in the volume of gray matter, according to the report published in the Feb. 1 issue of the journal Sleep.

The researchers said further research is needed to determine whether reduced gray matter concentration is caused by sleep apnea, or whether preexisting abnormalities contribute to the development of the problem.

More information

The U.S. National Heart, Lung, and Blood Institute has more about sleep apnea.