Sleep apnea harms heart health because of reduced blood oxygen, study shows
A new study suggests sleep apnea damages cardiovascular health due to reduced levels of oxygen. File Photo courtesy of Penn Medicine
Cardiovascular risks linked to sleep apnea are caused by a reduction in blood oxygen levels, according to National Institutes of Health-supported study published in the American Journal of Respiratory and Critical Care Medicine.
“Researchers have found that people with obstructive sleep apnea have an increased cardiovascular risk due to reduced blood oxygen levels, largely explained by interrupted breathing,” researchers said in a press release Wednesday.
They “sought to identify features of obstructive sleep apnea that could explain why some people were more likely than others to develop cardiovascular outcomes.”
Researchers studied data collected on 4,500 middle aged and older Americans who had participated in two prior studies, the Multi-Ethnic Study of Atherosclerosis and the Osteoporotic Fractures in Men Study.
The purpose of the research was to determine the mechanism that links sleep apnea to increased cardiovascular risks.
Those in the Multi-Ethnic Study of Atherosclerosis had a 45% increased risk of having a cardiovascular event for every measure of hypoxic burden, which measures severity of reduced blood oxygen levels. The Osteoporotic Fractures in Men Study showed a 13% increased risk.
The researchers found that hypoxic burden was mostly related to severe airway obstruction and not factors such as obesity.
“These findings will help better characterize high-risk versions of obstructive sleep apnea,” study co-author Ali Azarbarzin, director of the Sleep Apnea Health Outcomes Research Group at Harvard, said.
Earlier this year, a study from the Cleveland Clinic found that sleep apnea is associated with risks to brain health. Those researchers found that sleep apnea prevented patients from reaching the state of “deep sleep,” which the body needs to repair tissue.