Both daytime sleepiness and sleep apnea are common problems, with sleep apnea affecting up to 20 percent of older adults. According to a study published in the current issue of the journal SLEEP, if you're an older adult with sleep apnea excessive daytime sleepiness, your risk of death is more than two times higher than it is for people with neither problem. (The increased risk was insignificant for those with only one of the two, excessive daytime sleepiness or sleep apnea.)
"We did not find that being sleepy in and of itself was a risk," explained principal investigator and lead author Dr. Nalaka S. Gooneratne, assistant professor of medicine in the University of Pennsylvania Health System in Philadelphia. "Instead, the risk of increased mortality only seemed to occur when sleep apnea was also present."
According to the American Academy of Sleep Medicine, the most common form of sleep apnea is obstructive sleep apnea. This is when soft tissue in the back of the throat collapses and blocks the upper airway during sleep. Another risk facing older adults is central sleep apnea, which involves a repetitive absence of breathing effort during sleep caused by a dysfunction in the central nervous system or the heart. Only 4 percent of people in the study had central sleep apnea, and there was no meaningful change in the results when they were excluded from the analysis.
The study was done on 289 adults who were recruited between 1993 and 1998 and followed until September 2009. They had a median age of 78, and 74 percent were women. About half said they felt sleepy or struggled to stay awake during the day at least three to four times a week. Their level of sleep apnea was measured over the course of one night using polysomnography in a dedicated sleep lab. Participants were included in the sleep apnea group only if they had an "apnea-hypopnea" index of 20 or more breathing pauses per hour of sleep, considered a moderate to severe level of sleep apnea.
According to the authors, the mechanism by which sleep apnea and excessive daytime sleepiness increase the risk of death is unclear. They think that inflammation may be involved, and this could increase the risk of other medical problems such as hypertension. Further study needs to be done to see if sleep apnea treatment reduces the risk of death, said Gooneratne.
The treatment of choice for obstructive sleep apnea is CPAP therapy. This involves sleeping with a small device that provides a steady stream of air through a mask. This airflow keeps the airway open to prevent pauses in breathing and restore normal oxygen levels. There is a wide range of CPAP equipment available. If you have trouble sleeping through the night or if a loved one has noticed that you wake up regularly because you've stopped breathing and snoring is a serious issue, talk to your doctor.
The study was supported by the National Institutes of Health through the National Institute on Aging and the National Center for Research Resources. Help for people who have sleep apnea is available at more than 2,200 AASM-accredited sleep disorders centers across the US. An online directory of AASM-accredited sleep centers is available at www.sleepcenters.org.