HealthDay News — For individuals with obstructive sleep apnea, those with short respiratory event duration have an increased risk for mortality, according to a study published online Oct. 19 in the American Journal of Respiratory and Critical Care Medicine.
Matthew P. Butler, Ph.D., from the Oregon Institute of Occupational Health Sciences in Portland, and colleagues examined whether respiratory event duration predicts all-cause mortality in a prospective community-based cohort involving 5,712 participants with obstructive sleep apnea.
The researchers found that 1,290 deaths occurred over 11 years of follow-up. Individuals with events of the shortest duration had a significant hazard ratio for all-cause mortality of 1.31 after adjustment for demographic factors, apnea-hypopnea index, smoking, and prevalent cardiometabolic disease. The correlation was seen in men and women and was strongest for moderate sleep apnea (hazard ratio, 1.59).
“This result seems counter-intuitive because you might expect longer periods of not breathing to be more severe,” Butler said in a statement. “On the other hand, shorter periods of disturbed breathing indicate a low arousal threshold, which would associate with sleep fragmentation, elevated sympathetic tone, and greater risk for hypertension.”