BACKGROUND AND OBJECTIVE: Continuous positive airway pressure (CPAP) is the most common treatment for obstructive sleep apnoea (OSA), but many patients fail long-term therapy. Bilevel positive airway pressure (BPAP) is a potential alternative. We hypothesized that BPAP could improve treatment adherence and outcomes in patients who cannot tolerate CPAP.
METHODS: Patients with OSA who failed CPAP (usage < 4 h/day) and were referred to a tertiary sleep centre between 2014 and 2017 for BPAP were included. Age, gender, body mass index (BMI), co-morbidities, CPAP use and reasons for failure, Epworth Sleepiness Scale (ESS), sleep study data, spirometry data and average maximum nightly compliance were recorded.
RESULTS: A total of 52 patients with OSA requiring CPAP > 15 cm HO (71% male, age: 58 (15) years, BMI: 42.6 (10.1) kg/m, apnoea-hypopnoea index (AHI): 51.1 (30.4)/h) were studied; 62% had respiratory co-morbidities affecting nocturnal breathing including obesity hypoventilation syndrome and COPD; 25% had neuromuscular conditions; and 17% had cardiovascular disease. CPAP was used for 199 (106-477) days prior to referral for BPAP. Reasons for CPAP failure were intolerant pressures (23%), uncontrolled symptoms (23%), mask problems (21%), adverse effects (13%), claustrophobia (8%), co-morbidities (8%) and other issues (4%). Lower expiratory positive airway pressures were needed with BPAP compared to CPAP (10 (8-12) vs 16.8 (15.7-19.2) cm HO, P = 0.001); patients achieved better adherence to BPAP (7.0 (4.0-8.5) vs 2.5 (1.6-6.7) h/night, P = 0.028) and better symptom control (ESS: 4.0 (1.0-7.0) vs 10.0 (6.0-17.0) points, P = 0.039). 2 2 2
CONCLUSION: In patients with moderate-severe OSA who fail CPAP therapy due to low adherence, BPAP is well tolerated and achieves sufficient control of sleep-disordered breathing and its symptoms.
