Those Who Suffer From Sleep Apnea May Be At Higher Risk For Cognitive Decline


A recent study discovered that obstructive sleep apnea, a condition characterized by repeated breathing interruptions during sleep, has been found to have a negative impact on memory and cognitive abilities in middle-aged men. It is not uncommon for individuals to have sleep apnea without being aware of it, as the symptoms manifest during periods of non-wakefulness.

New research indicates that even individuals who are otherwise healthy and not overweight may experience early cognitive decline due to obstructive sleep apnea (OSA). According to the Sleep Foundation, OSA affects 10 to 30 percent of adults and leads to frequent disruptions in breathing during sleep. These interruptions in breathing have been associated with various severe health issues, including cardiovascular disease, diabetes, and even glaucoma. Furthermore, the disorder can increase the risk of premature death.

Previous studies have demonstrated that the intermittent deprivation of oxygen to the brain associated with OSA can affect both its structure and function. However, some research suggests that mental impairments observed in individuals with OSA may be attributed to co-occurring health conditions (known as comorbidities) that are associated with the apnea, such as hypertension, obesity, and small vessel disease in the brain.

“While we cannot claim causation, our findings suggest that obstructive sleep apnea itself may be sufficient to start damage in the brain, even in otherwise healthy patients,” said Ivana Rosenzweig, MD. She’s the lead study author and a neuropsychiatrist who heads the Sleep and Brain Plasticity Centre at King’s College London.

Sleep Apnea May be Enough to Cause Cognitive Problems

A study recently published in the journal Frontiers in Sleep on April 6 has revealed that men with obstructive sleep apnea (OSA) have poorer short-term memory and executive functioning compared to men without OSA. Executive functioning refers to mental processes such as planning, attention focus, memory, and multitasking abilities. Additionally, the study found that these men exhibited deficiencies in vigilance, sustained attention, as well as movement and impulse control.

The study involved a group of 27 men between the ages of 35 and 70 who had recently been diagnosed with mild to severe OSA but did not have any other accompanying medical conditions. These findings were then compared to a control group consisting of seven men who did not have OSA or any other medical conditions.

It is worth noting that the participants in the study were not smokers, alcohol abusers, or obese, as their body mass index (BMI) was below 30. To assess cognitive abilities, the researchers conducted a series of neuropsychological tests.

Dr. Rosenzweig, one of the researchers, highlighted an unexpected outcome of the study, which was that individuals with OSA also demonstrated deficits in social and emotional cognition.

“In our clinics, this has been often mentioned by patients’ partners. For example, the partners may sometimes report that a patient [with OSA] is ‘less emotionally present,’ or more irritable, or less altruistic. However, in studies so far, OSA has not been thought to be associated with this deficit,” said Rosenzweig.

Depression and anxiety has also been linked as effects brought about by sleep apnea.

The cognitive impairments observed in individuals with OSA are believed to be a result of various factors. The authors propose that intermittent episodes of low oxygen and high carbon dioxide levels in the bloodstream, alterations in cerebral blood flow, sleep disruptions, and brain inflammation contribute to these deficits.

According to Rosenzweig, OSA can cause the upper airway in the neck to partially or completely collapse during sleep. This is because the airway becomes more lax during sleep, leading to a reduction in the supply of oxygen to the blood and other abnormalities in blood gas levels. Additionally, this airway collapse disrupts sleep patterns and affects the normal flow of blood through the brain’s blood vessels.


Brain Health Can be Achieved with Uninterrupted Sleep

According to Dr. Colleen Lance, a physician on the staff of the Sleep Disorders Center at Cleveland Clinic’s Neurological Institute, it is essential for the body and mind to obtain sufficient and uninterrupted sleep in order to facilitate proper recovery.

“If your sleep time is cut short, or interrupted for whatever reason, there will be an impact on brain recovery resulting in cognitive decline,” Dr. Lance said. She was not part of the new study. “For example, animal research in Alzheimer’s disease has shown that lack of sleep or interrupted sleep results in buildup of the proteins — let’s call it ‘trash’ — associated with Alzheimer’s disease. Sleep allows your brain to ‘take out the trash,’ if you will. OSA can cause a great deal of disruption, and in effect not allow your brain to catch up on its rest.”

Lance points out that the study’s limited number of participants hampers the ability to draw firm conclusions. The researchers emphasize the necessity of a more extensive investigation to validate these initial findings.

Treatment for Sleep Apnea

The American Academy of Sleep Medicine strongly encourages individuals with sleep apnea to seek treatment. However, it emphasizes that a staggering 80 to 90 percent of adults with this condition remain unaware of their condition because the episodes of interrupted breathing occur during sleep.

Having a partner or someone who can observe your sleep may be beneficial in detecting the presence of sleep apnea. The Mayo Clinic identifies additional symptoms such as excessive daytime sleepiness, irritability, and waking up with a dry mouth.

The most commonly prescribed treatment for obstructive sleep apnea is the use of a CPAP (continuous positive airway pressure) machine. This device supplies a constant stream of air pressure to the throat, thereby keeping the airway open while you inhale. Making lifestyle changes, such as losing weight, can also be helpful in managing the condition.

“This disorder is relatively easily treatable, and yet it can lead to such serious and debilitating diseases, which once set, may not be so easily treatable,” Rosenzweig said.