Pressure reduction during exhalation in sleep apnea patients treated by continuous positive airway pressure.
BACKGROUND
This French, multicenter, randomized double-blind controlled trial tested the hypothesis that pressure reduction during exhalation (C-Flex; Respironics; Murrysville, PA) would improve continuous positive airway pressure (CPAP) compliance, comfort, and quality of life.


METHODS
Two hundred eighteen newly diagnosed sleep apnea patients (seven centers; mean [+/- SD] age, 55 +/- 11 years; mean body mass index, 31 +/- 6 kg/m(2); mean apnea-hypopnea index, 44 +/- 21 events/h) were randomly assigned to receive 3 months of treatment with CPAP (108 patients) or C-Flex (110 patients). Objective compliance, generic quality-of-life questionnaire (SF-36) scores, disease-specific quality-of-life questionnaire (Grenoble Sleep Apnea Quality of Life [GrenobleSAQOL]) scores, and visual analog scales for CPAP comfort and side effects were determined at baseline and after 3 months. After 3 months, patients in the CPAP arm were moved to the C-Flex arm for 3 additional months (open study).


RESULTS
An intention-to-treat analysis demonstrated that there were no differences at 3 months between C-Flex and CPAP use in terms of compliance, the rate of side effects, and comfort. Low compliers receiving CPAP therapy (< 4 h of use) significantly improved this outcome during the open study (p = 0.04). There was a significant improvement in six of eight of the SF-36 domain scores and in all of the domains of the GrenobleSAQOL scores in both groups using either CPAP or C-Flex.


CONCLUSIONS
In unselected sleep apnea patients, C-Flex was associated with similar outcomes to standard CPAP. Low compliers receiving CPAP therapy improved their adherence when moving to C-Flex.


BACKGROUND
ISRCTN Register Identifier: 08065291.
Pépin
Jean-Louis
JL
HP2 Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM), Equipe Région INSERM 17, Grenoble University Hospital, Grenoble, France. Electronic address: JPepin@chu-grenoble.fr.
Muir
Jean-François
JF
Service de Pneumologie, Hôpital Boisguillaume, Rouen, France.
Gentina
Thibaut
T
Clinique de La Louvière, Lille, France.
Dauvilliers
Yves
Y
University Hospital of Montpellier, Montpellier, France.
Tamisier
Renaud
R
HP2 Laboratory, Institut National de la Santé et de la Recherche Médicale (INSERM), Equipe Région INSERM 17, Grenoble University Hospital, Grenoble, France.
Sapene
Marc
M
Polyclinique de Bordeaux, Bordeaux, France.
Escourrou
Pierre
P
Service de Physiologie-Explorations Fonctionnelles, Hôpital A. Béclère, Assistance Publique-Hôpitaux de Paris, Clamart, France.
Fleury
Bernard
B
Service de Pneumologie, Hôpital St Antoine, Assistance Publique-Hôpitaux de Paris, Paris, France.
Philip-Joet
François
F
Service de Pneumologie, Hôpital St Joseph, Assistance Publique-Hôpitaux de Marseille, Marseille, France.
Philip
Pierre
P
Service de Physiologie-Explorations Fonctionnelles, Hôpital Pellegrin, Bordeaux, France.
d'Ortho
Marie-Pia
MP
Groupe Henri-Mondor Albert Chennevier, Service de Physiologie-Explorations Fonctionnelles, Assistance Publique-Hôpitaux de Paris, Créteil, France; Institut National de la Santé et de la Recherche Médicale (INSERM), Unité 841, Créteil, F-94010 France; Université Paris-7-Denis Diderot, Faculté de Médecine Xavier Bichat, Paris, France.
D000328:Adult; D000399:Air Pressure; D015992:Body Mass Index; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D004311:Double-Blind Method; D045853:Exhalation / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance / Q000706:statistics & numerical data; D017286:Polysomnography; D011788:Quality of Life; D012016:Reference Values; D018570:Risk Assessment; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000175:diagnosis / Q000628:therapy*; D018709:Statistics, Nonparametric; D013997:Time Factors; D016896:Treatment Outcome