Determinants of CPAP compliance in bariatric patients with obstructive sleep apnoea

Introduction: CPAP compliance is a challenge in the management of obstructive sleep apnoea (OSA), particularly in patients undergoing bariatric surgery. We investigated possible determinants of CPAP compliance in patients with OSA at a specialist bariatric centre. Methods: Retrospective cross-sectional study of all bariatric patients screened for OSA between 2013 and 2015. Case records and CPAP compliance at 28 days were reviewed for those with confirmed OSA and treated with CPAP. Multivariate analysis was performed on CPAP compliance against demographics, anthropometrics, Epworth Sleepiness Scale (ESS), objective measure of OSA and CPAP pressure. Results: 826 patients were screened, 92(11.1%) of whom had OSA and were commenced on CPAP. 51(55%) of the 92 patients were female, median (IQR) age 51(43-56) years, BMI 51.8(46.8-57) kgm −2 , baseline ODI 24.2(13.1-37.7) and baseline ESS 10(6-15). 34(37%) patients used their CPAP for ≥75% of nights and the mean(±SD) hours used per night was 4.0(±2.0). Humidification was the only factor which was related to mean hours of use of CPAP per night (β=0.235; p 0.05). None of the factors above were related to the proportion of nights with ≥3 hours of CPAP use (p>0.114). Conclusion: OSA prevalence and CPAP compliance in bariatric patients are low. Humidification was the only factor associated with CPAP compliance. There was no relationship between CPAP compliance and demographics, anthropometrics, OSA severity or CPAP pressure. Further study is warranted to investigate other possible determinants of CPAP compliance in this cohort.