March 10, 2003 -- There's been doubt about whether the most common sleep apnea treatment -- a machine that gently blows air into the nose -- does any good. Now new research shows this treatment really can help. But the jury's still out on whether it helps mild cases of this troublesome sleep disorder.
Doctors call the treatment continuous positive air pressure or CPAP. People with sleep apnea wake often during the night because their upper airways collapse and they can't breathe. The most common sleep apnea treatment is CPAP in which a machine blows air through a nose mask as a person sleeps. This "positive pressure" is supposed to keep airways open and cut down on the choking and snoring that plagues sleep apnea sufferers.
But does it really work? Earlier data on CPAP suggested that it didn't. Now a new review -- which includes new clinical trials -- says CPAP cuts down sleep apnea patients' daytime sleepiness. Sanjay R. Patel, MD, and colleagues at Brigham and Women's Hospital and Harvard Medical School, Boston, report the findings in the March 10 issue of the Archives of Internal Medicine.
"We believe this improvement in sleepiness is not only statistically significant but clinically important," Patel and colleagues write.
The effects of CPAP were much greater in people with severe sleep apnea than in those with mild symptoms.
"Patients with more severe apnea and sleepiness seem to benefit the most," Patel's team notes.
The review got its data from several different studies using different methods. Moreover, the studies lasted only four to six weeks. These are problems for Sardar I. Babar, MD, and Stuart F. Quan, MD, of Arizona Health Sciences Center, Tucson. Their editorial comment on the Patel study appears in the same issue of the Archives.
"The results [of the Patel study] are not definitive," Babar and Quan write. "This [study] proves that there is subjective benefit to patients with severe apnea who are treated with CPAP. However, there is insufficient evidence to indicate that patients with mild sleep apnea show any subjective improvement."
They note that a new study of CPAP in patients with mild sleep apnea is now getting started.