Gasping for air and stopping breathing while sleeping has been linked to depression, according to a new study from the Centers for Disease Control and Prevention.
The condition, known as sleep apnea, occurs when a person's breathing is paused or interrupted while sleeping. The pauses, which can last a couple seconds to a minute, can cut off oxygen from the brain and the rest of the body. Symptoms of the condition include snoring, daytime fatigue and restless sleep.
"When a person stops breathing like this, they are momentarily brought out of deeper levels of sleep," said Anne G Wheaton, a CDC epidemiologist and lead author of the study. "They may not fully wake up, but they will not get the proper amount of rest."
The study, published in the journal Sleep, analyzed nearly 10,000 American adults. Researchers found that the likelihood of depression in study participants increased along with the self-reported rate of gasping and stopping breathing while sleeping.
About 6 percent of men and 3 percent of women enrolled in the study reported having been diagnosed with obstructive sleep apnea. Otherwise, participants had not been diagnosed with the disorder, but described symptoms of gasping, snorting, restlessness while sleeping and daytime fatigue.
"Mental health professionals often ask patients with depression about their sleeping habits, and there is a known link between depression and insomnia, but less about depression and this specific sleep disorder," said Wheaton.
While there have been small studies with smaller study populations that have examined the link in the past, this is the first study to look at the link between sleep apnea and depression in the general population, said Wheaton.
Cells need oxygen to "perform whatever tasks there are for the brain to perform and if they're not getting enough, a person's physical and mental health seems to suffer," said Wheaton.
Men are more at risk of sleep apnea than women. Obesity puts people at greater risk of apnea because the extra weight around the neck can cut off breathing. Being older than 40 and having a large neck size also puts people at greater risk for the sleep disorder.
Despite the potential health issues associated with the disorder, most people are unaware of the difficulty they have breathing while sleeping. It is usually only after a bed partner notices the breathing problems that a diagnosis is revealed.
While the research adds an important element to understanding depression and sleep disorders, the findings should be taken with caution because of the study's self-reporting nature.
"People are poor reporters of their sleep symptoms in general," said Dr. Rosalind Cartwright, chairman of psychology at Rush University Medical Center. "The authors make up for this with large numbers to wash out error but [did] better if they asked the bed partner for these data."
There are several ways to treat sleep apnea, experts said, including airway pressure masks that can be placed over the nose and mouth while sleeping to keep the upper airway passages open. Surgery is available to remove excess tissue around the nose and throat that can cause snoring and block air passages.
Despite the availability of treatment, Cartwright said about 80 percent of people who snort or stop breathing five or more nights do not seek treatment and go undiagnosed.
"[That] is a headline all by itself," said Cartwright. "Couples get together to sleep together. Snorting drives them apart."