Severe sleep apnea linked to increased risk of stroke, cancer, death

Results of the 20-year follow-up study show that people with moderate to severe obstructive sleep apnea were four times more likely to die (hazard ratio = 4.2), nearly four times more likely to have a stroke (HR = 3.7), three times more likely to die from cancer (HR = 3.4), and 2.5 times more likely to develop cancer. Results were adjusted for potential confounding factors such as body mass index, smoking status, total cholesterol and blood pressure.

"Sleep apnea is a common disease that has a powerful impact on public health because it greatly increases the risk of strokes, cancers and mortality from any cause," said lead author Nathaniel S. Marshall, PhD, senior lecturer in clinical trials at the University of Sydney in Australia.

Study results are published in the April 15 issue of the Journal of Clinical Sleep Medicine, which is published by the American Academy of Sleep Medicine.

The study involved 397 adults who are participating in the ongoing Busselton Health Study. Objective sleep data were gathered in 1990 using a portable home sleep testing device. Participants with a history of stroke or cancer were excluded from selected analyses.

Prevalence rates were 4.6 percent for moderate to severe OSA and 20.6 percent for mild OSA. During the 20-year follow-up period there were 77 deaths and 31 strokes, as well as 125 cancer events that included 39 fatalities. Mild sleep apnea was not associated with increased health risks. "Obstructive sleep apnea is a chronic disease that can be destructive to your health," said American Academy of Sleep Medicine President Dr. Safwan Badr. "People with symptoms of sleep apnea, such as loud and frequent snoring or silent pauses in breathing during sleep, should see a board certified sleep medicine physician for a comprehensive sleep evaluation."

The authors noted that the results of their study are consistent with the findings of previous research conducted in the U.S. and Spain.

The research was supported by grants from the National Health and Medical Research Council in Australia.

The American Academy of Sleep Medicine reports that obstructive sleep apnea is a common sleep disorder that affects up to seven percent of men and five percent of women. It involves repetitive episodes of complete or partial upper airway obstruction occurring during sleep despite an ongoing effort to breathe. The most effective treatment option for OSA is continuous positive airway pressure (CPAP) therapy, which helps to keep the airway open by providing a stream of air through a mask that is worn during sleep.