Loss of Brain Stem Cells may cause Central Sleep Apnea

August 9th 2005

Loss of Brain Stem Cells may cause Central Sleep Apnea Study UCLA CPAP machine

CPAP machine

Researchers at the University of California at Los Angeles (UCLA) reported Monday that they believe that people who die in their sleep may stop breathing because they have lost too many brain cells. They tested Rats and determined that the loss of key brain stem cells may halt autonomic functions such as breathing.

As we age we naturally lose these brain stem cells. According to Jack Feldman, the principle investigator and distinguished professor of neurobiology at the David Geffen School of Medicine at UCLA "We wanted to reveal the mechanism behind central sleep apnea, which most commonly affects people after age 65."

Professor Feldman continued "Unlike obstructive sleep apnea — in which a person stops breathing when their airway collapses — central sleep apnea is triggered by something going awry in the brain's breathing center."

In previous research Feldman’s team identified a region of the brain stem responsible for breathing they dubbed preBotzinger complex (preBotC). They called this area the “command post for generating breathing in mammals”, and identified a small group of preBötC neurons responsible for issuing the commands.

This research studied the role of preBotC neurons during sleep. They killed more than half of the preBotC neurons in a number of adult rats. The results were dramatic after just a few nights of study. The rats completely quit breathing during REM sleep which forced "the rat to wake up in order to start breathing again," according to Leanne McKay, postdoctoral fellow in neurobiology. "Over time, the breathing lapses increased in severity, spreading into non-REM sleep and eventually occurring when the rats were awake, as well."

Humans possess a few thousand of these specialized preBotC cells, and they are slowly lost over a lifetime. "We speculate that our brains can compensate for up to a 60 percent loss of preBötC cells, but the cumulative deficit of these brain cells eventually disrupts our breathing during sleep. There's no biological reason for the body to maintain these cells beyond the average lifespan, and so they do not replenish as we age," Feldman said. "As we lose them, we grow more prone to central sleep apnea."

According to the UCLA team when elderly but otherwise healthy people die during sleep, physicians commonly record the cause of death as heart failure. Feldman believes that it is likely the deaths occurred from central sleep apnea. The scientists suspect “central sleep apnea also strikes people suffering the late stages of neurodegenerative disorders, such as Parkinson's disease, Lou Gehrig's disease and multiple system atrophy, all serious conditions that lead to movement problems.”

Most people with sleep apnea don’t realize they have sleep apnea. You are asleep and don’t realize you stop breathing. During the day it is unlikely you stop breathing. When you sleep your throat becomes relaxed and collapses (obstructive type apnea).

If you suspect you have sleep apnea a sleep study can be done. Of the two types of apnea, obstructive is far more common. If you snore there is a good chance you have obstructive sleep apnea. Sleep apnea is a likely cause of various ailments including high blood pressure in the early morning, a tired feeling during the day and a loss of cognitive ability. As apneas occur blood pressure rises. It has been speculated that this could cause strokes and heart attacks.

There are treatments for both sleep types of sleep apnea. The most common treatment for sleep apnea is a CPAP (constant positive air pressure) machine. There is a special type of CPAP called a Bi-PAP that may help individuals with central sleep apnea. These machines will almost always stop the user from snoring (the wife will love it).

Talk to your doctor. Most insurance companies cover the sleep study and CPAP machine. If you do not have insurance ask for a discount from the specialists. The online edition of Nature Neuroscience reported the findings on Aug. 7.