The effectiveness of oropharyngeal exercises compared to inspiratory muscle training in obstructive sleep apnea: A randomized controlled trial

Background Inspiratory muscle training (IMT) and oropharyngeal exercises (OE) have different advantages and disadvantages and a comparison of these modalities has been recommended. The aim of this study was to compare the effects of IMT and OE on important outcomes for patients with OSAS. Methods This was a randomized controlled clinical trial. Forty-one clinically stable OSAS patients not receiving CPAP therapy were randomly divided into three groups. Patients in the IMT group (n = 15) trained with a threshold loading device 7 days/week for 12 weeks. Patients in the OE group (n = 14) practiced exercises 5 days/week for 12 weeks. Twelve patients served as control group. Apnea–hypopnea index (AHI), respiratory muscle strength, snoring severity and frequency (Berlin Questionnaire), daytime sleepiness (Epworth Sleepiness Scale; ESS), sleep quality (Pittsburg Sleep Quality Index; PSQI), impact of sleepiness on daily life (Functional Outcomes of Sleep Questionnaire; FOSQ), and fatigue severity (Fatigue Severity Scale; FSS) were evaluated before and after the interventions. Results AHI and sleep efficiency did not change significantly in any of the groups. Significant decreases in snoring severity and frequency, FSS and PSQI total scores were found in the IMT and OE groups after the treatments (p < 0.05). There was a significant reduction in neck and waist circumference and significant improvement in respiratory muscle strength (MIP and MEP) in IMT group compared to control group (p < 0.05). The%MEPpred value and FOSQ total score significantly increased and ESS score reduced after the treatment in OE group compared to control group (p < 0.05). Conclusions Our results indicate that both OE and IMT rehabilitation interventions are applicable in rehabilitation programs for OSAS patients who do not accept CPAP therapy. Our findings could lead to increase these methods’ use among rehabilitation professionals and decrease in cost of CPAP treatment in OSAS.