Severe Sleep Apnea Nearly Doubles Risk of Death
Sleep apnea can raise the chance of dying by as much as 46%.
Sleep apnea is a form of sleep-disordered breathing characterized by nightly bouts of interrupted, oxygen-deprived sleep. It is often associated with hypertension and cardiovascular disease.
Researchers at John Hopkins and six other U.S. medical centers report in the the Public Library of Science, Medicine that as little as 11 minutes a night spent in severe sleep apnea with its subsequent oxygen deprivation doubled the death rate in men. In severe sleep apnea the blood oxygen levels drop below 90%.
The study involved 6,441 men and women between ages 40 to 70 participating in the Sleep Heart Health Study. The sleep apnea ranged from none to mild to severe forms of sleep apnea. They were followed for an average of 8 years.
Among the general population, it is estimated that 24% of American men and 9% of women have irregular breathing patterns during sleep. Most are unaware that they have a problem.
Among the men in the study, 42.9% did not have sleep-disordered breathing, 33.2% had mild disease, 15.7 % had moderate disease, and 8.2% had severe disease. Among the women in the study, about 25% had mild sleep apnea, 8% had moderate disease and 3% had severely disordered breathing.
There have been 1,047 deaths (460 women) among study participants since the clinical investigation began. Men had a higher mortality rate than women (24.8 versus 16.5 per 1,000 person-years) despite similar age and weight. The risk of death was double for men with severe disease (32.2 per 1,000 person–years) compared to those with no sleep-disordered breathing (16.8 per 1,000 person-years).
Women in the study who died and had severe sleep apnea were too few for researchers to draw a similar conclusion at this stage in the study, but researchers suspect that further research will bear the same results.
Key among treatments for sleep apnea is use of overnight sleeping aids, such as the CPAP (continuous positive airway pressure) device. The device, which resembles a typical oxygen mask, is worn over the nose and connected by a thin tube to a machine that forces air into the nasal passages, preventing the airways from collapsing.
John Hopkins Medicine News Release
Punjabi NM, Caffo BS, Goodwin JL, Gottlieb DJ, Newman AB, et al. 2009; Sleep-Disordered Breathing and Mortality: A Prospective Cohort Study; PLoS Med 6(8): e1000132. doi:10.1371/journal.pmed.1000132