title: A randomised controlled trial of CPAP versus non-invasive ventilation for initial treatment of obesity hypoventilation syndrome.
abstract: Obesity hypoventilation syndrome (OHS) is the most common indication for home ventilation, although the optimal therapy remains unclear, particularly for severe disease. We compared Bi-level and continuous positive airways pressure (Bi-level positive airway pressure (PAP); CPAP) for treatment of severe OHS.
  
  
  
  We conducted a multicentre, parallel, double-blind trial for initial treatment of OHS, with participants randomised to nocturnal Bi-level PAP or CPAP for 3 months. The primary outcome was frequency of treatment failure (hospital admission, persistent ventilatory failure or non-adherence); secondary outcomes included health-related quality of life (HRQoL) and sleepiness.
  
  
  
  Sixty participants were randomised; 57 completed follow-up and were included in analysis (mean age 53 years, body mass index 55 kg/m2, PaCO260 mm Hg). There was no difference in treatment failure between groups (Bi-level PAP, 14.8% vs CPAP, 13.3%, p=0.87). Treatment adherence and wake PaCO2were similar after 3 months (5.3 hours/night Bi-level PAP, 5.0 hours/night CPAP, p=0.62; PaCO244.2 and 45.9 mm Hg, respectively, p=0.60). Between-group differences in improvement in sleepiness (Epworth Sleepiness Scale 0.3 (95% CI -2.8, 3.4), p=0.86) and HRQoL (Short Form (SF)36-SF6d 0.025 (95% CI -0.039, 0.088), p=0.45) were not significant. Baseline severity of ventilatory failure (PaCO2) was the only significant predictor of persistent ventilatory failure at 3 months (OR 2.3, p=0.03).
  
  
  
  In newly diagnosed severe OHS, Bi-level PAP and CPAP resulted in similar improvements in ventilatory failure, HRQoL and adherence. Baseline PaCO2predicted persistent ventilatory failure on treatment. Long-term studies are required to determine whether these treatments have different cost-effectiveness or impact on mortality.
  
  
  
  ACTRN12611000874910, results.
authors.affiliation: Institute for Breathing and Sleep, Heidelberg, Australia.|Austin Health, Heidelberg, Australia.|University of Melbourne, Parkville, Australia.|Monash University, Clayton, Australia.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Howard
authors.affiliation: Royal Prince Alfred Hospital, Camperdown, Australia.
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Piper
authors.affiliation: Institute for Breathing and Sleep, Heidelberg, Australia.|Austin Health, Heidelberg, Australia.
authors.forename: Bronwyn
authors.initials: B
authors.lastname: Stevens
authors.affiliation: Institute for Breathing and Sleep, Heidelberg, Australia.|Alfred Health, Melbourne, Australia.|La Trobe University, Melbourne, Australia.
authors.forename: Anne E
authors.identifier: 0000-0003-2061-845X
authors.initials: AE
authors.lastname: Holland
authors.affiliation: Royal Prince Alfred Hospital, Camperdown, Australia.
authors.forename: Brendon J
authors.initials: BJ
authors.lastname: Yee
authors.affiliation: Monash University, Clayton, Australia.|Alfred Health, Melbourne, Australia.
authors.forename: Eli
authors.initials: E
authors.lastname: Dabscheck
authors.affiliation: Monash University, Clayton, Australia.
authors.forename: Duncan
authors.initials: D
authors.lastname: Mortimer
authors.affiliation: Alfred Health, Melbourne, Australia.
authors.forename: Angela T
authors.initials: AT
authors.lastname: Burge
authors.affiliation: Royal Prince Alfred Hospital, Camperdown, Australia.
authors.forename: Daniel
authors.initials: D
authors.lastname: Flunt
authors.affiliation: Alfred Health, Melbourne, Australia.
authors.forename: Catherine
authors.initials: C
authors.lastname: Buchan
authors.affiliation: Institute for Breathing and Sleep, Heidelberg, Australia.|Austin Health, Heidelberg, Australia.
authors.forename: Linda
authors.initials: L
authors.lastname: Rautela
authors.affiliation: Institute for Breathing and Sleep, Heidelberg, Australia.|Austin Health, Heidelberg, Australia.
authors.forename: Nicole
authors.initials: N
authors.lastname: Sheers
authors.affiliation: Sir Charles Gairdner Hospital, Nedlands, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Hillman
authors.affiliation: Institute for Breathing and Sleep, Heidelberg, Australia.|Austin Health, Heidelberg, Australia.|University of Melbourne, Parkville, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Berlowitz
mesh_terms: D015992:Body Mass Index; D045422:Continuous Positive Airway Pressure; D004311:Double-Blind Method; D023381:Endpoint Determination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D063087:Noninvasive Ventilation / Q000379:methods*; D010845:Obesity Hypoventilation Syndrome / Q000503:physiopathology / Q000628:therapy*; D010349:Patient Compliance; D011788:Quality of Life; D012129:Respiratory Function Tests; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
keywords: Non invasive ventilation; Sleep apnoea