The role of long-term continuous positive airway pressure in the progression of obstructive sleep apnoea: A longitudinal cohort study

Recent evidence suggests that short-term obstructive sleep apnea (OSA) treatment could affect OSA pathogenesis such as ventilatory control. The aim of our present study was to identify the impact of long-term treatment on the change in pathogenesis and natural progression of OSA. In a longitudinal analysis of a non-obese cohort study, patients with OSA treated with either continuous positive airway pressure (CPAP) or an oral appliance (OA), interrupted their treatment for 1 week and underwent a polysomnography (PSG) off treatment that was compared with their initial PSG taken 5 years before treatment initiation. In all, 154 consecutive patients with OSA who were treated by CPAP using an auto-titrating continuous positive airway pressure device (CPAP-APAP) (n = 112), or by OA (n = 27) or were untreated (n = 15), PSG was performed twice with a median (range) follow-up of 93 (60-176) months. Multivariate logistic regression showed that reduction of body mass index (BMI) and good treatment adherence to be significant predictors of favourable OSA progression, as represented by an improved or unchanged apnea-hypopnea index (AHI) (odds ratios were 5.14 and 2.89, respectively). Amongst the patients with an unchanged BMI and good CPAP-APAP adherence (n = 55), the improvement in AHI was significantly associated with the decrease in supine non-rapid eye movement-AHI and mixed apnoea index/apnoea index, which are generally recognised to be determinants of ventilator instability. These findings suggest that not only weight but also treatment adherence are determinants in the natural progression of OSA severity.

Automated summary

Research suggests that reducing body mass index and maintaining good treatment adherence are significant predictors of favorable progression in obstructive sleep apnea (OSA). Among patients with unchanged BMI and good treatment adherence, improvement in apnea-hypopnea index (AHI) was significantly associated with decreases in certain index indicators, which are known to relate to ventilator instability. This highlights the importance of weight and treatment adherence in the natural progression of OSA severity.