The two previously known types of sleep apnea include obstructive sleep apnea and central sleep apnea. In obstructive sleep apnea, the more common form, the throat muscles relax and the airway is narrowed, momentarily cutting off breathing and resulting in noisy snoring. With central sleep apnea, the brain does not send proper signals to the muscles that control breathing. The newly discovered type, complex sleep apnea, is a combination of both obstructive and central sleep apneas.
Patients with complex sleep apnea at first appear to have obstructive sleep apnea and stop breathing 20 to 30 times per hour each night. But unlike typical obstructive sleep apnea patients, their breathing problem is not completely alleviated by a CPAP (continuous airway pressure) machine, which functions like a pneumatic splint to open a patient's airway. Instead, once the CPAP is applied to complex sleep apnea patients, the obstruction seems to dissipate, but still they do not breathe properly. Symptoms of central sleep apnea then appear and fragmented sleep results, due to frequent pauses in breathing.
"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," says Timothy Morgenthaler, M.D., Mayo Clinic sleep medicine specialist, pulmonologist and lead study investigator. "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 attempt to categorize these people."
The study involved a retrospective review of 223 patients consecutively referred to the Mayo Clinic Sleep Disorders Center over one month, plus 20 consecutive patients diagnosed with central sleep apnea. The investigators found that complex sleep apnea comprised 15 percent of all sleep apnea patients, while 84 percent had obstructive sleep apnea and 0.4 percent had central sleep apnea. They also discovered that males have a higher tendency to have complex sleep apnea. Dr. Morgenthaler says this may be due to less stable respiratory control in males than females. The complex sleep apnea patients had sleep and cardiovascular histories similar to the obstructive sleep apnea patients. The complex sleep apnea patients also had fewer complaints about waking up after initially falling asleep than those with central sleep apnea (32 percent vs. 79 percent). The investigators found that complex sleep apnea could be diagnosed based on patients' sleep patterns defined at their initial diagnostic exams plus lack of response to CPAP.
According to Dr. Morgenthaler, no known factors influence risk for complex sleep apnea. An effective treatment has not been identified, but research continues to test breathing assistance machines to alleviate this condition's symptoms.
Lisa Lucier | EurekAlert!
A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital
Stem cell transplants: activating signal paths may protect from graft-versus-host disease
20.04.2017 | Technische Universität München
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
24.04.2017 | Physics and Astronomy
24.04.2017 | Materials Sciences
24.04.2017 | Life Sciences