title: Oronasal Masks Require a Higher Pressure than Nasal and Nasal Pillow Masks for the Treatment of Obstructive Sleep Apnea.
abstract: Oronasal masks are frequently used for continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnea (OSA). The aim of this study was to (1) determine if CPAP requirements are higher for oronasal masks compared to nasal mask interfaces and (2) assess whether polysomnography and patient characteristics differed among mask preference groups.
  
  
  
  Retrospective analysis of all CPAP implementation polysomnograms between July 2013 and June 2014. Prescribed CPAP level, polysomnography results and patient data were compared according to mask type (n = 358).
  
  
  
  Oronasal masks were used in 46%, nasal masks in 35% and nasal pillow masks in 19%. There was no difference according to mask type for baseline apnea-hypopnea index (AHI), body mass index (BMI), waist or neck circumference. CPAP level was higher for oronasal masks, 12 (10-15.5) cm H2O compared to nasal pillow masks, 11 (8-12.5) cm H2O and nasal masks, 10 (8-12) cm H2O, p < 0.0001 (Median [interquartile range]). Oronasal mask type, AHI, age, and BMI were independent predictors of a higher CPAP pressure (p < 0.0005, adjusted R(2) = 0.26.). For patients with CPAP ≥ 15 cm H2O, there was an odds ratio of 4.5 (95% CI 2.5-8.0) for having an oronasal compared to a nasal or nasal pillow mask. Residual median AHI was higher for oronasal masks (11.3 events/h) than for nasal masks (6.4 events/h) and nasal pillows (6.7 events/h), p < 0.001.
  
  
  
  Compared to nasal mask types, oronasal masks are associated with higher CPAP pressures (particularly pressures ≥ 15 cm H2O) and a higher residual AHI. Further evaluation with a randomized control trial is required to definitively establish the effect of mask type on pressure requirements.
  
  
  
  A commentary on this article appears in this issue on page 1209.
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.
authors.forename: Sheetal
authors.initials: S
authors.lastname: Deshpande
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|School of Clinical Sciences, Monash University, Victoria, Australia.
authors.forename: Simon
authors.initials: S
authors.lastname: Joosten
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.
authors.forename: Anthony
authors.initials: A
authors.lastname: Turton
authors.affiliation: Sleep and Circadian Medicine Laboratory, Department of Physiology Monash University, Melbourne, Victoria, Australia.|School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia.
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Edwards
authors.affiliation: Sleep and Circadian Medicine Laboratory, Department of Physiology Monash University, Melbourne, Victoria, Australia.
authors.forename: Shane
authors.initials: S
authors.lastname: Landry
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Victoria, Australia.
authors.forename: Darren R
authors.initials: DR
authors.lastname: Mansfield
authors.affiliation: Department of Lung and Sleep Medicine, Monash Health, Victoria, Australia.|School of Clinical Sciences, Monash University, Victoria, Australia.
authors.forename: Garun S
authors.initials: GS
authors.lastname: Hamilton
mesh_terms: D001315:Australia; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008397:Masks; D008875:Middle Aged; D009666:Nose; D017286:Polysomnography; D011312:Pressure; D012189:Retrospective Studies; D020181:Sleep Apnea, Obstructive / Q000628:therapy*; D016896:Treatment Outcome
keywords: CPAP; mask; nasal mask; nasal pillows; obstructive sleep apnea; oronasal mask; treatment