More Evidence that Sleep Apnea Damages the Brain

Researchers at the UCLA School of Nursing recently uncovered another reason to see your doctor right away if you suspect you have sleep apnea.

According to a recent news release published on the EurekaAlert.com website, the researchers observed weaker blood flow in patients with sleep apnea. The weakened blood flow is believed to be a contributing factor in impaired brain function often associated with sleep apnea.

Effects of Sleep Apnea on Blood Flow

With each breathing pause that occurs during a sleep apnea episode, the blood oxygen level drops. These breathing pauses occur quite frequently throughout the night, resulting in the body not getting the oxygen it needs.

Left untreated, sleep apnea can cause damage to many cells in the body. It can also cause a host of serious health conditions such as diabetes, hypertension, heart disease and stroke. In regards to brain function, sleep apnea can cause memory problems, difficulty concentrating, daytime sleepiness and mood swings.

Study Findings

To measure blood flow in the brain, the researchers used a procedure called a global blood volume and oxygen dependent (BOLD) signal, a procedure typically used to monitor brain activity. Blood flow was measured in the brains of men and women with and without sleep apnea. Measurements were taken while both groups were awake and while both groups performed three types of physical tasks

The first task required the participants to perform the Valsalva maneuver, where each individual breathes forcefully through a small tube. This raises pressure in the chest cavity. The second task was a “hand-grip challenge” that required the participants to squeeze hard with their hands. The third task was a “cold pressor challenge” that involved immersing each participant’s right foot in icy water for 60 seconds.

The researchers saw a weaker blow flow response in the participants with OSA during the cold-pressor and hand-grip challenges. Little difference was observed between the two groups when they performed the Valsava maneuver.

The researchers attributed the weaker blood flow readings in the OSA group to the fact that signals from the arm and leg nerves must travel through the regions of the brain that control muscle movement and sensation. This process can possibly be delayed by OSA-associated brain damage. The physical requirements of the Valsalva maneuver does not involve the muscle-controlling or sensory parts of the brain.

Women Found More Susceptible

The study also found that women with sleep apnea were more likely to have weaker blood flow measurements than men. UCLA School of Nursing has published other studies that have also found that women experience more severe brain injuries from sleep apnea than men. Research will continue to be done in search of sleep apnea treatments that could reverse the brain damaging effects of the disorder.

By Ramie A Tritt, MD, President, Atlanta ENT