title: Effect of Semirecumbent Sleep Position on Severity of Obstructive Sleep Apnea in Patients With Heart Failure.
abstract: BACKGROUND
  Overnight rostral leg fluid displacement in heart failure (HF) patients is related to the high prevalence and severity of obstructive sleep apnea syndrome (OSAS). We hypothesized that rostral fluid shift would decrease in a semirecumbent (45-degree elevated) position, and evaluated the effect of semirecumbent sleeping on severity of sleep apnea in HF patients with OSAS.
  
  
  RESULTS
  Demographic, anthropometric characteristics, and medical history of 30 consecutive patients with HF and OSAS were recorded. The patients underwent 2 polysomnographic procedures within 1 week: 1 while lying flat and the other in a semirecumbent position. Out of 30 patients (mean age 54.7 ± 10.2, 26 men), 16 (53.3%) were obese and 29 (96.7%) had comorbidities other than HF. Mean apnea-hypopnea index was 30.8 ± 20.7 events/h while lying flat which decreased to 17.8 ± 12.1 events/h in semirecumbent position (P < .0001). Similarly, oxygen desaturation index decreased from 22.3 ± 19.8 to 12.7 ± 11.5 events/h (P < .0001), and the percentage of sleep time with oxygen saturation (SpO2) <90% (P = .036) and lowest SpO2 (P = .004) were improved in the semirecumbent position. Furthermore, the percentage of stage N2 sleep decreased from 47.0% while lying flat to 39.6% (P = .014).
  
  
  CONCLUSIONS
  The present findings support that the severity of OSAS decreased significantly in a semirecumbent sleep position in patients with HF. Therefore, semirecumbent sleeping may be a promising therapeutic option in the management of HF-related sleep apnea.
authors.affiliation: Department of Chest Diseases, Ege University Faculty of Medicine, Izmir, Turkey. Electronic address: ozen.basoglu@ege.edu.tr.
authors.forename: Ozen K
authors.initials: OK
authors.lastname: Basoglu
authors.affiliation: Ege University Faculty of Medicine, Izmir, Turkey.
authors.forename: Bengisu
authors.initials: B
authors.lastname: Keskin
authors.affiliation: Department of Chest Diseases, Ege University Faculty of Medicine, Izmir, Turkey.
authors.forename: Mehmet Sezai
authors.initials: MS
authors.lastname: Tasbakan
authors.affiliation: Department of Cardiology, Ege University Faculty of Medicine, Izmir, Turkey.
authors.forename: Cemil
authors.initials: C
authors.lastname: Gurgun
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000639:trends*; D011187:Posture; D011446:Prospective Studies; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D012894:Sleep Stages / Q000502:physiology*; D016683:Supine Position
keywords: Obstructive sleep apnea; fluid shift; heart failure; semirecumbent sleep position