A clinical investigation of obstructive sleep apnea syndrome (OSAS) and upper airway resistance syndrome (UARS) patients.

Objective: (i) Evaluation of the clinical differences and similarities presented by patients diagnosed as OSAS and UARS subjects. (ii) Evaluation of the ability of a sleep disorders specialist to dissociate the two syndromes based upon clinical evaluation.Population: 314 subjects were included. They were referred to a sleep disorders clinic with complaints of loud snoring during a 3 month period.Method: The evaluation consisted of: (i) Clinical interview and evaluation. (ii) Administration of validated questionnaires (Sleep Disorders Questionnaire and Epworth Sleepiness Scale). (iii) Establishment of clinical diagnostic and results of polygraphic recording.Results: After clinical evaluation and polygraphic recordings (performed within 3 weeks of initial evaluation) patients were subdivided into two groups: 176 OSAS and 128 UARS. The misclassification of patients by specialists correlated with body mass index (BMI) measurement, with an over classification of patient as OSAS when a high BMI was noted and vice-versa for UARS. The only significant difference between OSAS and UARS patients was an older age and a wider neck circumference in the OSAS group than in UARS patients.Conclusion: Clinical presentation including daytime sleepiness complaint and ESS score is similar for patients with and without drop of oxygen saturation below 90% during sleep. There was always a male predominance within both syndromes, but more women were diagnosed with UARS than with OSAS.