A recent study published in Frontiers in Sleep suggests that obstructive sleep apnea may lead to early cognitive deficits in middle-aged men, even in the absence of comorbidities and obesity. The study, which included 27 men with a new diagnosis of mild to severe obstructive sleep apnea and a control group of seven healthy men, evaluated cognitive function using the Cambridge Neuropsychological Test Automated Battery of Tests. The results showed that men with severe obstructive sleep apnea displayed deficits in vigilance, executive functioning, short-term visual recognition memory, and social and emotional recognition. The men with mild obstructive sleep apnea also showed some difficulties in these areas, but not as severe as those with severe forms of the disorder. The cognitive difficulties observed could be due to intermittent low oxygen, high carbon dioxide in the blood, changes in blood flow to the brain, sleep fragmentation, and neuroinflammation.
The authors note that previous studies attributed cognitive deficits to comorbid conditions rather than sleep apnea. The study’s lead author, Ivana Rosenzweig, MD, Ph.D., FRCPsych, a sleep physician and consultant neuropsychiatrist, explains that “most patients with this disorder have already present comorbidities when we see them the first time in the — so it has always been close to impossible to delineate whether it was these diseases, or sleep apnea itself, that caused the damage.”
Obstructive sleep apnea is characterized by the sleeper momentarily but repeatedly stopping breathing because the muscles in the back of the throat relax and collapse, blocking the airway. It affects between 25 and 30 percent of men and between 9 and 17 percent of women in the United States. The most effective treatment for obstructive sleep apnea is using a continuous positive airway pressure (CPAP) machine, but there are also self-care techniques that can be used at home to help relieve some of the symptoms and promote a good night’s sleep.
The study’s findings suggest that obstructive sleep apnea may be sufficient to “kick-start” cognitive changes and increase the risk of cognitive decline and dementia. Sleep disturbances increase dementia risk, but unfortunately, dementia can also lead to sleep disturbances, resulting in a downward spiral. Therefore, it is crucial to identify and treat sleep issues during early and mid-life adult development to delay the age of onset of dementia.