Analysing snoring sounds for obstructive sleep apnea (OSA) patients

Several studies have done in order to determine the relationship between snoring and obstructive sleep apnea syndrome (OSAS). One of the common problem that is faced during the medical treatment of the apnea is the undetermination of the efficiency of the applied treatment in terms of objective criteria. It is needed to automatically detect each snoring episode in order to estimate the spectral features and determine the snoring sound intensity. In this study, an automatic detection system of acoustic snoring signals has been designed, to work with long duration respiratory sound recordings. The system was designed to select snoring episodes from simple snorers and OSAS patients and to reject the undesired waveforms. The sound recordings were taken from patients that are suspected of OSAS pathology while they were connected to the polysomnography in Gulhane Military Medical Academy (GMMA) Sleep Studies Laboratory. In order to validate the system, 500 snores were analysed taken from 30 patients with different apnea/hypopnea index (AHI). Results were compared with manual annotations done by a medical doctor and the average sensitivity of the system is determined as 86%.