title: Daytime polysomnography for early diagnosis and treatment of patients with suspected sleep-disordered breathing.
abstract: Excessive daytime sleepiness (EDS) is a common complaint among patients with sleep-disordered breathing (SDB). Population-based studies on traffic and industrial accidents suggest a relationship between EDS and life-threatening events, and adults with EDS have cognitive and memory problems. Nocturnal polysomnography (nPSG) is essential for diagnosing SDB but it is time and energy consuming. We examined the usefulness of daytime polysomnography (dPSG) for the early diagnosis and treatment of patients with suspected SDB. We studied 108 consecutive patients aged 51.9 +/- 13.5 years (mean+/-SD). All patients underwent dPSG and nPSG. The number of apnea/hypopnea episodes per hour (apnea/hypopnea index: AHI) and the number of 3% desaturation episodes per hour (desaturation index: DSI) were calculated. All patients were classified into two groups. The REM group consisted of subjects who had an AHI < or = 25/h, AHI(REM)/AHI(NREM) > 2, and AHI(NREM) < 15/h. Those who did not satisfy these criteria were placed in the NREM group. Continuous positive airway pressure (CPAP) titration was performed for patients whose AHI was > or =20/h on dPSG. Using the international classification of sleep disorders, 96 patients were diagnosed as obstructive sleep apnea [including five upper airway resistance syndrome (UARS) patients], six patients were snoring, four had idiopathic hypersomnia due to a medical condition, and two had circadian rhythm sleep disorders. The sensitivity of dPSG for AHI was 81.0%, specificity was 100%, and accuracy was 83.5%. The sensitivity and accuracy of dPSG for AHI in the REM group were considerably lower than in the NREM group. There was no significant difference for optimal CPAP between dPSG and nPSG. In the five patients with UARS, their AHI, DSI, and arousal index on dPSG were 0.92 +/- 1.2/h, 2.9 +/- 3.4/h, and 29.3 +/- 3.5/h, respectively, and their AHI and DSI on nPSG were 3.2 +/- 2.5/h and 2.8 +/- 2.4/h, respectively. However, their respiratory effort-related arousals were 37.9 +/- 7.4/h, and their arousal index was 33.2 +/- 6.3/h. The five patients with UARS were also treated with CPAP, and their daytime sleepiness was improved. Although dPSG has limitations, these results indicate that dPSG recording is clinically useful for the diagnosis of and determination of types of treatment in patients with suspected SDB.
authors.affiliation: Department of Pathophysiological Laboratory Sciences, Nagoya University, Graduate School of Medicine, 1-1-20 Daiko-Minami, Nagoya-shi, 61-8673 Aichi, Japan.
authors.forename: Seiko
authors.initials: S
authors.lastname: Miyata
authors.forename: Akiko
authors.initials: A
authors.lastname: Noda
authors.forename: Seiichi
authors.initials: S
authors.lastname: Nakata
authors.forename: Hidehito
authors.initials: H
authors.lastname: Yagi
authors.forename: Eriko
authors.initials: E
authors.lastname: Yanagi
authors.forename: Kumiko
authors.initials: K
authors.lastname: Honda
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Sugiura
authors.forename: Shigeru
authors.initials: S
authors.lastname: Nakai
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nakashima
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Koike
mesh_terms: D000328:Adult; D002940:Circadian Rhythm; D045422:Continuous Positive Airway Pressure; D006970:Disorders of Excessive Somnolence / Q000145:classification* / Q000175:diagnosis*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods*; D015203:Reproducibility of Results; D012119:Respiration; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000145:classification* / Q000175:diagnosis*; D012895:Sleep, REM; D012913:Snoring / Q000175:diagnosis