Switching continuous positive airway pressure–treated patients to autotitrating positive airway pressure (APAP) systems resulted in reduced severity of patient-reported aerophagia symptoms, according to results from a double-blind, randomized study.
Aerophagia, the swallowing of air leading to gastrointestinal distress, is a frequently reported adverse effect among people treated for obstructive sleep apnea with continuous positive airway pressure (CPAP).
The APAP-treated group saw significantly reduced median therapeutic pressure levels compared with the CPAP-treated patients (9.8 vs. 14.0 cm H2O, P less than .001) and slight but statistically significant reductions in self-reported symptoms of bloating, flatulence, and belching. No significant difference was seen in compliance with therapy between the two treatment groups in this study, published in the August 2017 issue of Journal of Clinical Sleep Medicine (J Clin Sleep Med. 2017;13[7]:881-8).
For their research, Teresa Shirlaw and her colleagues in the sleep clinic at Princess Alexandra Hospital in Woolloongabba, Queensland, Australia, analyzed results from 56 adult patients with sleep apnea who had been recently treated with CPAP and reported bloating, flatulence, or belching following therapy.
Patients were randomized 1:1 to in-clinic nighttime CPAP or APAP for 2 weeks and blinded to treatment assignment, while investigators recorded therapy usage hours, pressure, leak, and residual apnea-hypopnea index across the study period. Most of the subjects (n = 39) used full face masks, while others used nasal-only systems.
The researchers considered differences in PAP therapy usage of at least 30 minutes per night to be statistically significant. The APAP group used the assigned therapy a mean 7 hours per night, vs. 6.8 for the CPAP group. Daytime sleepiness outcomes were also similar for the two treatment groups.
Ms. Shirlaw and her colleagues described the compliance findings as a surprise, noting that an earlier meta-analysis had shown slight improvements in compliance associated with APAP (Syst Rev. 2012;1[1]:20). In clinical practice, patients complaining of aerophagia associated with CPAP are frequently switched to APAP based on the belief that doing so “will lead to improved therapy acceptance and … improved compliance,” they wrote.
The investigators described the self-reporting of aerophagia symptoms as one of the study’s limitations. They surmised that the lack of difference seen for compliance measures might be explained in part by the 30-minute usage increments in the study design (compared with 10-minute increments used in some other studies), and the fact that the cohort had relatively high compliance with CPAP at baseline (5.5 hours/night), suggesting a motivated patient population at entry.
The study received some funding from the government of Queensland, and the authors disclosed no conflicts of interest related to their findings.