The finding on sleep apnea is based on new results from the Wisconsin Sleep Cohort, an 18-year observational study supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.
At the start of the study, researchers found that adults (ages 30 to 60) with sleep-disordered breathing were two to three times more likely to die from any cause compared to those who did not have sleep-disordered breathing.
The risk of death was not brought about by factors like age, gender, body mass index (an indicator of overweight or obesity), or cardiovascular health status, but by the severity of the sleep-disordered breathing.
During the study, researchers followed 1522 generally healthy men and women for an average of 13.8 years after testing them for sleep-disordered breathing using a standard overnight sleep test.
It was found that the subjects with severe sleep-disordered breathing were three times more likely to die during the study than those without breathing problems during sleep, and that those who did not get treatment were at an even greater risk.
Further study revealed that participants with untreated severe sleep-disordered breathing were four times more likely to die from any cause and five times more likely to die from cardiovascular conditions.
The findings suggest that the treatment of severe sleep-disordered breathing may be protective, especially against cardiovascular deaths.
The condition is brought about when periodically during sleep, the upper airway becomes narrowed or blocked, and air has trouble reaching the lungs; in some cases, breathing stops completely (called apnea) for seconds to minutes at a time.
The frequent pauses in breathing disrupt sleep and prevent adequate amounts of oxygen from entering the bloodstream.
Interruptions in breathing are potentially serious medical conditions and should be evaluated by a physician to determine whether treatment is needed.
Because affected individuals are asleep and typically unaware of the breathing problems, and the condition cannot be diagnosed during routine physician office visits, most people with sleep-disordered breathing are undiagnosed.
Untreated sleep-disordered breathing has been linked to a greater risk of cardiovascular disease and risk factors - including high blood pressure, stroke, and diabetes -- as well as to excessive daytime sleepiness, which can impair quality of life and performance on the job or in school, and increase the risk of injury or death from work-related accidents and vehicular crashes.
Common signs that should be discussed with a physician include complaints of snoring from bed partners, excessive daytime sleepiness, and morning headache.
Sleep-disordered breathing occurs in people of all ages, but is more common in men, the elderly, and overweight individuals.
"Sleep-Disordered Breathing and Mortality: Eighteen-Year Follow-Up of the Wisconsin Sleep Cohort," is published August 1 in the journal Sleep.