By Morgan Jones
A poor night's sleep can affect performance at work the next day, but over time, could disrupted sleep affect brain function in a permanent way? New evidence suggests it could.
A new study found that patients with issues like sleep apnea or heavy snoring developed problems with cognition around 10 years earlier than those without sleep-breathing troubles.
"Abnormal breathing patterns during sleep such as heavy snoring and sleep apnea are common in the elderly, affecting about 52 percent of men and 26 percent of women," explained the study's lead author, Ricardo S. Osorio, M.D., of the NYU School of Medicine in New York, in a press release.
In sleep apnea, breathing starts and stops repeatedly over the course of the night. Osorio and team wanted to see whether sleep apnea and other abnormal breathing patterns (called sleep-disordered breathing) were tied to cognitive issues.
To do so, these researchers looked at data from the Alzheimer’s Disease Neuroimaging Initiative, which involved over 2,000 adults between the ages of 55 and 90. Some patients had no cognitive problems, while some developed Alzheimer's disease or mild cognitive impairment (MCI). In MCI, cognitive issues have developed beyond what is expected in normal aging but not far enough to be considered dementia.
Osorio and team found that patients who had sleep-disordered breathing started showing signs of cognitive problems an average of 10 years earlier than those who did not have issues with abnormal breathing patterns during sleep.
When looking only at patients with cognitive issues, those with sleep-disordered breathing started showing signs of MCI at an average age of 77. The same was true for those without the breathing troubles at an average age of 90.
In this group of patients, Alzheimer's disease was also seen earlier -- at an average age of 83 among those with sleep-disordered breathing, compared to an average age of 88 among those without breathing issues.
Osorio and team also looked at the effects of treating abnormal breathing patterns with continuous positive airway pressure (CPAP). CPAP delivers air pressure through a mask during sleep, helping to keep the airways open.
Treatment with CPAP seemed to reduce the risk of developing cognitive issues earlier, Osorio and colleagues found. Patients who used CPAP developed MCI at an average age of 82, compared to an average age of 72 among those who did not receive treatment for their sleep-disordered breathing.
"These findings were made in an observational study and as such, do not indicate a cause-and-effect relationship,” Osorio noted. “However, we are now focusing our research on CPAP treatment and memory and thinking decline over decades, as well as looking specifically at markers of brain cell death and deterioration.”
This study was published online April 15 in the journal Neurology.
Several study authors received industry support within the past two years and held patents involving procedures related to the study. A number of groups funded this research, such as the Foundation for Research in Sleep Disorders and the Alzheimer’s Disease Neuroimaging Initiative.