Blood Flow May Explain Link Between Sleep Apnea & Stroke

Research has shown that obstructive sleep apnea (OSA) increases your risk of stroke. According to the UCLA Stroke Center, OSA is found in almost 50 percent of stroke patients. But the mechanism by which sleep apnea increases stroke risk has been unknown.

A new study may provide an answer. It shows that people with sleep apnea have decreased blood flow velocity in the brain’s arteries. Their brains’ blood vessels also have a lower rate of recovery when blood pressure drops.

These effects may impair the brain’s ability to regulate its blood flow. This may contribute to the increased risk of stroke in people with sleep apnea.

A stroke is a “brain attack” that occurs when blood flow to the brain is interrupted. It can result from either a blood clot that blocks an artery or from a broken blood vessel. Stroke is the third leading cause of death in the U.S. as of 2005.

OSA involves repeated breathing pauses that occur during sleep. It can result in severe changes in blood pressure and oxygen levels.

Research also has linked sleep apnea to health risks such as high blood pressure, coronary artery disease, heart attack and heart failure. Recent studies even show that sleep apnea increases your risk of death.

The good news is that sleep apnea can be treated. CPAP therapy helps normalize breathing during sleep. A 2005 study shows that CPAP may help protect people with sleep apnea from stroke and heart disease. In effect, regular CPAP use to treat sleep apnea just might save your life.