Sleep apnea linked to heart disease

New research in the U.S. suggests that people who suffer from sleep apnea have an increased risk of heart disease.

Obstructive sleep apnea (OSA) results in multiple breathing interruptions while sufferers are asleep which happens when tissue in the back of the throat collapses and blocks the airway.

The researchers say there is mounting evidence that the condition plays a potentially important role in cardiovascular disease.

As well as cardiovascular disease, the other effects of OSA include daytime sleepiness, alertness and concentration deficiencies, and an increased risk of hypertension, stroke and diabetes.

Dr. Sean M. Caples, one of the authors of the study, says there is abundant physiologic evidence implicating obstructive sleep apnea in perpetuating, if not inciting, heart failure.

Dr. Caples, of the Mayo Clinic College of Medicine in Rochester, Minnesota, says "in addition to their association with systemic hypertension, obstructive sleep apnea-related stressors ... have varying effects on heart oxygen supply and demand, particularly in the already compromised heart".

Dr. Lawrence Epstein, past president of the American Academy of Sleep Medicine, medical director of Sleep HealthCenters and an instructor of medicine at Harvard Medical School, says treating sleep disorders and getting an adequate amount of sleep are pillars of good cardiovascular health.

Epstein says that sleep apnea is a known risk factor for the development of hypertension, heart disease and stroke, and chronic sleep deprivation has been shown to change metabolic function in a way that promotes weight gain and diabetes, two risk factors for heart disease.

OSA can occur in men and women of any age, but it is most common in obese, middle-aged men.

The American Academy of Sleep Medicine estimates that four percent of men and two percent of women have OSA, and millions more remain undiagnosed.

Safe and effective treatments are available for those with OSA and scientific evidence shows that continuous positive airway pressure (CPAP) is the best treatment for OSA.

CPAP provides a steady stream of pressurized air to patients through a mask that they wear during sleep and this airflow keeps the airway open, preventing the pauses in breathing that characterize sleep apnea and restoring normal oxygen levels.

Sleep apnea is more common among people who have high blood pressure, large tonsils, nasal congestion or are overweight. More men than women over age 40 suffer from the condition and women with a neck circumference larger than 16 inches are at increased risk for OSA.

In men, a neck circumference greater than 17 inches puts them at risk.

Those who think they might have OSA, or another sleep disorder, are urged to discuss their problem with their doctor who will refer them to a sleep specialist.

The study is published in the current issue of the journal Sleep.