By Robert McCoy, MD
Swedish/Edmonds Sleep Center
What do snoring and heart attacks have in common? They’re both associated with obstructive sleep apnea (OSA) – a sleep disorder. Patients who have OSA stop breathing while they’re asleep. Their throat muscles relax during sleep, blocking the flow of air and causing them to stop breathing (apnea literally means not breathing). As a result, this causes the oxygen levels in their blood to drop and they need to wake up in order to start breathing again. This process can occur repeatedly throughout the night.
OSA has long been associated with snoring, fatigue and drowsiness. But more recently, it has been shown to be a factor in many cardiovascular diseases as well due to stress on the body from the accumulation of drops in oxygen over time. The theory is that night time oxygen drops and arousals lead to continual cardiac overstimulation and eventually to heart damage.
It’s estimated that 15-20 percent of the adult population in the United States currently has OSA. As our population becomes increasingly overweight, the incidence of OSA has also become more prevalent. It is estimated that 90 percent of people with OSA are undiagnosed.
Hypertension (high blood pressure), is the most common cardiovascular disease affecting 30 percent of adults in the U.S. Medical research has clearly established that OSA can cause hypertension. Studies show that the degree of hypertension is directly linked to the severity of the sleep apnea. If a person has both OSA and hypertension, the blood pressure is more difficult to control. The good news is that treatment of OSA will improve the blood pressure.
OSA has a significant impact on coronary artery disease (CAD). This disease is three to five times more prevalent in those with sleep apnea. They have higher rates of heart attack and stroke; and death is more likely in those diagnosed with OSA. Effective treatment of sleep apnea decreases CAD and the resulting cardiovascular complications.
Irregular heartbeats (arrhythmias) and heart failure are higher in those with OSA. The incidence of cardiac arrhythmias is four times greater in people with OSA . Sleep apnea may be present in as many as 80 percent of those with atrial fibrillation (a type of arrhythmia). Fifty percent of people with congestive heart failure have been shown to also have OSA. Therapy for sleep apnea reduces arrhythmias and improves heart function.
OSA is a cardiovascular disease. If present, it can cause hypertension, heart attack and stroke. Effective treatment for sleep apnea is available and will decrease the risk for cardiovascular diseases back to a level comparable to people without OSA.
To learn more about obstructive sleep apnea or other sleeping disorders, call the Swedish/Edmonds Sleep Center at 425-640-4660.