Feb 21 2005
An overnight sleep test is required to distinguish ordinary snorers from persons with obstructive sleep apnea syndrome (OSAS), according to a study in the current issue of Archives of Otolaryngology - Head & Neck Surgery.
Alfred Dreher, M.D., of Ludwig-Maximilians-University, Munich, Germany and colleagues assessed the predictive power of medical history and routine physical examination as performed by an ENT specialist to identify OSAS in patients seeking treatment for snoring. The researchers evaluated 101 patients who came to an ENT clinic complaining of snoring using a routine examination, consisting of a medical history and an assessment of the anatomy of four points in their nose and throat, on a scale of zero to three and a test of the degree of obstruction in the throat. The patients were then also evaluated using standard polysomnography over the course of two nights.
Snoring is one of the main symptoms of OSAS, but while 30 to 50 percent of the general population snores, only 2 to 4 percent have OSAS, according to background information in the article. The otorhinolaryngologic (ENT: ear, nose and throat physician) specialist must distinguish between these two entities to provide appropriate treatment. The current methods for diagnosing OSAS are the measure of oxygen saturation and airflow or polysomnography, an overnight test to evaluate sleep disorders which includes simultaneous monitoring of a number of parameters including the patient's airflow through the nose and mouth, snoring, oxygen saturation, electroencephalogram (recording of the electrical activity of the brain), and body position. Although polysomnography is considered the gold standard for diagnosis of OSAS, the authors note, both of these current techniques are cumbersome.
The differences in the anatomical measures between those patients with a diagnosis of OSAS confirmed by polysomnography and the other patients were not statistically significant, although patients with the confirmed diagnosis tended to report the occurrence of apneas more often. "None of the reported medical history and/or anatomical parameters alone or in combination could be used to distinguish patients with OSAS from snoring patients," the authors write.
"In our opinion, all patients seeking treatment for snoring should be screened overnight using a device measuring at least oxygen saturation and airflow," the authors conclude. "If the results are suggestive of OSAS, or if patients complain of excessive daytime sleepiness, standard polysomnography should be applied. In conclusion, we believe that medical history, anatomical findings, and functional factors are insufficient to adequately predict the presence or absence of OSAS."