title: All night analysis of time interval between snores in subjects with sleep apnea hypopnea syndrome.
abstract: Sleep apnea-hypopnea syndrome (SAHS) is a serious sleep disorder, and snoring is one of its earliest and most consistent symptoms. We propose a new methodology for identifying two distinct types of snores: the so-called non-regular and regular snores. Respiratory sound signals from 34 subjects with different ranges of Apnea-Hypopnea Index (AHI = 3.7-109.9 h(-1)) were acquired. A total number of 74,439 snores were examined. The time interval between regular snores in short segments of the all night recordings was analyzed. Severe SAHS subjects show a shorter time interval between regular snores (p = 0.0036, AHI cp: 30 h(-1)) and less dispersion on the time interval features during all sleep. Conversely, lower intra-segment variability (p = 0.006, AHI cp: 30 h(-1)) is seen for less severe SAHS subjects. Features derived from the analysis of time interval between regular snores achieved classification accuracies of 88.2 % (with 90 % sensitivity, 75 % specificity) and 94.1 % (with 94.4 % sensitivity, 93.8 % specificity) for AHI cut-points of severity of 5 and 30 h(-1), respectively. The features proved to be reliable predictors of the subjects' SAHS severity. Our proposed method, the analysis of time interval between snores, provides promising results and puts forward a valuable aid for the early screening of subjects suspected of having SAHS.
authors.affiliation: Department ESAII, Universitat Politècnica de Catalunya, Barcelona, Spain. jmesquita@ibecbarcelona.eu
authors.forename: J
authors.initials: J
authors.lastname: Mesquita
authors.forename: J
authors.initials: J
authors.lastname: Solà-Soler
authors.forename: J A
authors.initials: JA
authors.lastname: Fiz
authors.forename: J
authors.initials: J
authors.lastname: Morera
authors.forename: R
authors.initials: R
authors.lastname: Jané
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D012720:Severity of Illness Index; D012815:Signal Processing, Computer-Assisted; D012891:Sleep Apnea Syndromes / Q000150:complications* / Q000175:diagnosis*; D012913:Snoring / Q000209:etiology*; D013018:Sound Spectrography / Q000379:methods; D013997:Time Factors