This Surprising Factor May Influence Your Risk Of Sleep Apnea

You know those nights when your brain refuses to switch off? Maybe you're dealing with a stressful project, feeling isolated, or simply carrying more than usual.

Then you finally fall asleep, only to wake up feeling like you barely rested. For some people, stress may be doing more than making it harder to wind down. It could also affect how they breathe during sleep.

In a recent study published in PNAS, researchers explored whether chronic psychosocial stress could contribute to sleep apnea, using both animal experiments and human genetic data.

About the study

Sleep apnea, which affects roughly 1 billion adults worldwide, happens when breathing repeatedly stops or becomes restricted during sleep.

Those interruptions lower blood oxygen and activate the body's stress response, so stress has long been viewed as a consequence of the condition.

But stress-related conditions such as anxiety are known to double the risk, and the researchers wanted to test whether the relationship also runs the other way. Could ongoing psychological and social stress make someone more vulnerable to sleep apnea in the first place?

They came at it two ways.

Adult rats were housed alone for three weeks to model chronic social stress, then monitored during sleep and tested for how strongly their breathing responded to low oxygen and high carbon dioxide.

The team also ran Mendelian randomization, a method for exploring potential cause-and-effect relationships, on genetic data from European cohorts ranging from roughly 100,000 to more than a million people, examining whether genetic tendencies toward stress and loneliness tracked with sleep apnea.

The rats showed a clear change in breathing

Living alone put the rats under stress, and they had more pauses in breathing while they slept. Their breathing also reacted more strongly when oxygen levels dropped or carbon dioxide levels rose.

The effect was stronger in male rats.

When researchers tested them under anesthesia, isolated males had five times more episodes where their airways became blocked and their blood oxygen dropped. Female rats did not show the same increase.

Changes in the nerves and muscles that help keep the airway open may have played a role.

The isolated rats also had higher blood pressure and gained more body fat, especially the males.

The human findings pointed in a similar direction. People with a genetic tendency toward loneliness had a higher risk of sleep apnea, even after researchers accounted for body fat. So, the link wasn't simply that loneliness might lead to weight gain, which then increases sleep apnea risk.

Stress may be another piece of the sleep apnea puzzle

These findings raise the possibility that chronic psychosocial stress can influence sleep apnea risk, rather than simply appearing as a consequence of sleep apnea itself.

The researchers describe it as an opening to treat stress as a risk factor worth targeting in prevention and treatment.

Still, there's a lot we don't know. The animal and human findings came from different approaches, so they can't be treated as proof that feeling stressed or lonely causes sleep apnea in people.

The human analysis also focused on genetic tendencies toward loneliness rather than asking people how stressed they felt day to day.

The sex difference in the rats is another open question, and whether the male-specific pattern holds in humans still needs to be studied.

What this means for your sleep

The findings don't mean stress is suddenly the main cause of sleep apnea. Established risk factors, including excess weight, still matter.

But chronic stress is worth taking seriously for plenty of reasons, and sleep may be one more.

Staying socially connected, making room for activities that help you decompress, and working with a therapist or other qualified professional when stress feels difficult to manage can all support overall well-being.

Just don't write off persistent sleep symptoms as "just stress." If you regularly snore, wake up gasping or choking, or feel exhausted despite spending enough time in bed, talk with a doctor.

Sleep apnea can be diagnosed and treated.

The takeaway

Chronic psychosocial stress and loneliness may be linked to a greater risk of sleep apnea, according to new animal and human genetic research.

The connection is still being worked out, but it adds another reason to take both chronic stress and persistent sleep symptoms seriously.