title: Heart rate-based nighttime awakening detection.
abstract: Sleep fragmentation is a cause of impaired daytime performance. We have developed an algorithm for detection of nighttime awakenings based on heart rate. As much as 15 healthy normal sleepers, 23 +/- 3 years, participated in this study. The dataset contains 33 nights of polysomnographic (PSG) and electrocardiographic (ECG) measurements. After a habituation night, the subjects underwent a reference night without interventions, followed by some nights with interventions. These included noise, light, physical and cognitive interventions. Nighttime awakenings were subdivided in to awakenings (>15 s) and short awakenings (<15 s). The overall number of awakenings was 18.5 (+/-10.5) and short awakenings 13.2 (+/-10.5). The number of nighttime awakenings did not differ significantly between the reference and intervention nights; a repeated measures ANOVA resulted in a p value of 0.66 for awakenings and 0.57 for short awakenings. As much as 5 reference nights were used as training set, 28 as validation set. The algorithm detects the awakening periods with a sensitivity of 80.5% (confidence interval 77.9-82.9%). Heart rate is an adequate measure that allows for detection of nighttime awakenings and hence sleep quality.
authors.affiliation: M3-BIORES, KULeuven, Kasteelpark Arenberg 30, bus 2456, 3001 Heverlee, Belgium.
authors.forename: Arnoud
authors.initials: A
authors.lastname: Bulckaert
authors.forename: Vasileios
authors.initials: V
authors.lastname: Exadaktylos
authors.forename: Guido
authors.initials: G
authors.lastname: De Bruyne
authors.forename: Bart
authors.initials: B
authors.lastname: Haex
authors.forename: Elke
authors.initials: E
authors.lastname: De Valck
authors.forename: Johan
authors.initials: J
authors.lastname: Wuyts
authors.forename: Johan
authors.initials: J
authors.lastname: Verbraecken
authors.forename: Daniel
authors.initials: D
authors.lastname: Berckmans
mesh_terms: D000328:Adult; D000465:Algorithms; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D017286:Polysomnography; D012890:Sleep / Q000502:physiology*; D055815:Young Adult