Experts Spot New Form of Sleep Apnea (article)

FRIDAY, Sept. 1 (HealthDay News) -- Mayo Clinic researchers say
they've identified a new type of sleep apnea called "complex sleep
apnea" that may be resistant to standard treatment such as continuous
positive airway pressure (CPAP).

"All of us in our sleep lab have observed for years that there are
patients who appear to have obstructive sleep apnea, but the CPAP
doesn't make them all that much better -- they still have moderate to
severe sleep apnea even with our best treatment and subjectively
don't feel they're doing very well," study lead investigator Dr.
Timothy Morgenthaler, a sleep medicine specialist and pulmonologist,
said in a prepared statement.

Until now, obstructive sleep apnea and central sleep apnea have been
the two known types of apnea. Obstructive sleep apnea, which is most
common, occurs when the throat muscles relax and the airway narrows,
which momentarily cuts off breathing and causes loud snoring. In
central sleep apnea, the brain fails to send the proper signals to
the muscles that control breathing.

Complex sleep apnea is a combination of both obstructive and central
sleep apnea, according to the Mayo researchers. Their findings were
published in the September issue of the journal Sleep.

The study of 223 patients referred to the Mayo Clinic Sleep Disorder
Center found that 15 percent of the patients had complex sleep apnea,
84 percent had obstructive sleep apnea and 0.4 percent had central
sleep apnea. Males are more likely to have complex sleep apnea.

At first, patients with complex sleep apnea appear to have
obstructive sleep apnea and stop breathing 20 to 30 times per hour
each night. However, unlike people with typical obstructive sleep
apnea, the breathing problems in patients with complex sleep apnea
aren't completely relieved by a CPAP machine, which keeps a patient's
airway open during sleep.

"When they put on a CPAP machine, they start to look like central
sleep apnea syndrome patients. This phenomenon has been observed for
years, but this study is the first to attempt to categorize these
people," he said.

There are no known risk factors for complex sleep apnea, and an
effective treatment for the condition has not yet been identified,
Morgenthaler said.

More information

The American Academy of Family Physicians has more about sleep apnea.

article found
at: http://news.yahoo.com/s/hsn/20060901/hl ... sleepapnea

This topic has been posted on a few different threads over the past couple of days. Nevertheless, isn't "complex" apnea the same as "mixed" apnea and hasn't mixed apnea been known for a while now?

My sleep study actually had an index for "mixed" apnea ... although mine turned out to be zero for both mixed and centrals. What have the Mayo clinic people been doing that they are unaware of mixed apnea?

- roberto