title: Validation of the System One RemStar Auto A-Flex for Obstructive Sleep Apnea Treatment and Detection of Residual Apnea-Hypopnea Index: A European Randomized Trial.
abstract: OBJECTIVE
  Autotitrating continuous positive airway pressure (CPAP) devices adjust pressure in response to changes in airflow and are an alternative to attended in-laboratory titration polysomnography (PSG) to determine optimal pressure levels. The aim of this study was to compare the performance of the System One RemStar Auto A-Flex (Philips Respironics, Murrysville, PA, USA) automatically adjusted positive airway pressure (APAP) mode to manually titrated, fixed pressure CPAP and to validate the device's breathing event detection capabilities against attended in-laboratory PSG.
  
  
  METHODS
  Sixty-one patients investigated in five centers for moderate to severe obstructive sleep apnea between May 2012 and June 2013 were invited to participate. Participants underwent two full-night attended polysomnograms in random order with manually titrated, fixed pressure CPAP versus APAP.
  
  
  RESULTS
  Fifty-three participants with a mean apnea-hypopnea index (AHI) of 45.9 ± 23 completed two sleep studies and were included in the analysis. There were significant but not clinically relevant differences between APAP and CPAP respectively: Apnea index [1.0 (2.8 ± 0.8), median (mean ± standard deviation)] versus [1.8 (5.3 ± 11.5)], p = 0.004; percentage of N1 sleep [12.3 (15.9 ± 0.5)] versus [14.3 (18.9 ± 12.7)], p = 0.028. AHI values differed between PSG [2.8 (5.5. ± 9.3)] and device [3.7 (6.0 ± 8.6)], p = 0.003). Regarding residual events detection, intraclass correlation coefficients for AHI were strong (0.956, p < 0.001) and the area under the curve was 0.988 (AHI cut-off value of 10).
  
  
  CONCLUSIONS
  The new APAP modality was effective and residual apnea-hypopnea indices calculated by the device strongly correlated to those assessed by PSG.
  
  
  CONCLUSIONS
  A commentary on this article appears in this issue on page 167.
authors: Université d'Angers, Angers, France; CHU d'Angers, Département de Pneumologie, Angers, France.
authors: Frédéric
authors: F
authors: Gagnadoux
authors: Sleep Medicine Centre, Kempenhaeghe, HEEZE, The Netherlands.|Department of Internal Medicine, Faculty of Medicine and Health Sciences, University of Ghent, Belgium.
authors: Dirk
authors: D
authors: Pevernagie
authors: Danish Center for Sleep Medicine, University of Copenhagen, Glostrup Hospital.
authors: Poul
authors: P
authors: Jennum
authors: Danish Center for Sleep Medicine, University of Copenhagen, Glostrup Hospital.
authors: Nina
authors: N
authors: Lon
authors: University Grenoble Alpes, Grenoble, France.|CHU de Grenoble, Laboratoire EFCR, Clinique Universitaire de Physiologie, Grenoble, France.
authors: Corinne
authors: C
authors: Loiodice
authors: University Grenoble Alpes, Grenoble, France.|CHU de Grenoble, Laboratoire EFCR, Clinique Universitaire de Physiologie, Grenoble, France.
authors: Renaud
authors: R
authors: Tamisier
authors: Sleep Medicine Centre, Kempenhaeghe, HEEZE, The Netherlands.
authors: Petra
authors: P
authors: van Mierlo
authors: Université d'Angers, Angers, France; CHU d'Angers, Département de Pneumologie, Angers, France.
authors: Wojciech
authors: W
authors: Trzepizur
authors: Ev. Krankenhaus Herne, Schlaflabor, Herne, Germany.
authors: Martina
authors: M
authors: Neddermann
authors: Ev. Krankenhaus Herne, Schlaflabor, Herne, Germany.
authors: Annika
authors: A
authors: Machleit
authors: Philips Home Healthcare Solutions, Murrysville, PA.
authors: Jeffrey
authors: J
authors: Jasko
authors: University Grenoble Alpes, Grenoble, France.|CHU de Grenoble, Laboratoire EFCR, Clinique Universitaire de Physiologie, Grenoble, France.
authors: Jean Louis
authors: JL
authors: Pépin
mesh_terms: D001049:Apnea / Q000503:physiopathology; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation* / Q000379:methods*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D015203:Reproducibility of Results; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology / Q000628:therapy*
keywords: APAP; CPAP; residual event detection; sleep apnea