Getting off the couch and into activities that get your body moving is linked to a decreased risk of obstructive sleep apnea (OSA), according to a wide-scale study that highlights the hazards of leading a sedentary life.
The study, published in the European Respiratory Journal, tracked around 130,000 men and women in the U.S. over a period of 10 to 18 years and found that more movement and less sedentary behaviour were associated with a lower likelihood of OSA. “In our study, higher levels of physical activity and fewer hours of TV watching and sitting either at work or away from home were associated with lower OSA incidence after accounting for potential confounders,” said Tianyi Huang, an associate epidemiologist at Brigham and Women’s Hospital, a teaching hospital affiliated with Harvard University. “Our results suggest that promoting an active lifestyle may have substantial benefits for both prevention and treatment of OSA.”
A 2014 study estimated that around 5.4 million Canadians have either been diagnosed with sleep apnea or are at high risk of the disorder. OSA, the most common type of sleep apnea, occurs when the upper airways become blocked, often because the soft tissue at the back of the throat collapses and obstructs the flow of oxygen to the lungs. This passage can also become comprised in people with large tongues, relaxed throat muscles or narrow airways.
Family members are usually aware of the issue before those with the actual disorder, largely because obstructed airways can result in loud snoring followed by choking or gasping for breath during sleep. Many of the symptoms of OSA are felt the next day, including a morning headache, fatigue, irritability or mood changes, poor concentration, memory loss or a lowered sex drive. Serious cases of OSA can increase the risk of heart issues, including heart failure.
Researchers used statistical modelling to compare physical activity and sedentary hours to OSA diagnoses. Moderate and vigorous physical activity were looked at separately and both were found to be strongly tied a lower risk of OSA, with no real difference detected between the intensity of the activity. The correlation was strongest for women, adults over the age of 65 and those with a BMI greater or equal to 25 kg/m2.
“Most prior observational studies on the associations of physical activity and sedentary behaviour with OSA were cross-sectional, with incomplete exposure assessment and inadequate control for confounding,” Huang said. “This is the first prospective study that simultaneously evaluates physical activity and sedentary behaviour in relation to OSA risk.”
The study’s large sample size and analysis of different levels of activity lend credibility to its findings, researchers said, but the self-reported nature of sedentary and physical activity may not have been the most ideal method of data collection. Next steps will likely involve using home sleep apnea tests and non-invasive monitoring methods to confirm the findings, Huang said. The study also focused only on recreational physical activity and not similar behaviour in the work place. Sedentary behaviour was characterized as sitting while watching TV or sitting away from work or home, a definition that may need to be broadened.
Still, the associations were strong enough for researchers to encourage doctors to preach the importance of physical activity as a bulwark against OSA. “We found that physical activity and sedentary behaviour are independently associated with OSA risk,” Huang said. “That is, for people who spend long hours sitting every day, increasing physical activity in their leisure time can equally lower OSA risk. Similarly, for those who are not able to participate in a lot of physical activity due to physical restrictions, reducing sedentary hours by standing or doing some mild activities could also lower OSA risk.
“Those who can lower sedentary time and increase physical activity would have the lowest risk.”
Dave Yasvinski is a writer with Healthing.ca