WASHINGTON — People with the severe form of apnea, which interferes with sleep, are several times more likely to die from any cause than are folks without the disorder, researchers report in today’s edition of the journal Sleep.
The findings in the 18-year study confirm smaller studies that have indicated an increased risk of death for people with apnea, also known as sleep-disordered breathing.
“This is not a condition that kills you acutely. It . . . erodes your health over time,” said Dr. Michael Twery, director of the National Center on Sleep Disorders Research.
The National Heart, Lung and Blood Institute, of which Twery’s center is part, estimates that 12 million to 18 million people in the U.S. have moderate to severe apnea. The condition is not always detected because the sufferer is asleep when the problem occurs and it cannot be diagnosed during a routine office visit with a doctor.
For people with apnea, their upper airway becomes narrowed or blocked periodically during sleep. That keeps air from reaching the lungs. In some cases, breathing stops for seconds to a minute or so; the pauses in breathing disrupt sleep and prevent adequate amounts of oxygen from entering the bloodstream.
“When you stop breathing in your sleep, you don’t know it; it doesn’t typically wake you up,” Twery said.
Instead, it can move a person from deep sleep to light sleep, when breathing resumes. But the overall sleep pattern is disturbed, and it can happen hundreds of times a night.
The institute, part of the National Institutes of Health, says apnea has been linked to a greater risk of heart disease, high blood pressure, stroke, diabetes and excessive daytime sleepiness.
In the new report, the Wisconsin Sleep Cohort followed 1,522 men and women, ages 30 to 60.
The annual death rate was 2.85 per 1,000 people per year for people without sleep apnea. People with mild and moderate apnea had death rates of 5.54 and 5.42 per 1,000, respectively, and people with severe apnea had a rate of 14.6.
Cardiovascular mortality accounted for 26 percent of all deaths among people without apnea and 42 percent of the deaths among people with severe apnea.
