A Comparison of Snoring Changes With a Supine-Avoidance Alarm Device Compared to Constant Positive Airway Pressure Treatment in Patients With Supine-Predominant OSA.

This study aimed to quantify how much snoring occurs in patients with supine-predominant OSA and the comparative effectiveness of supine-avoidance therapy versus CPAP to reduce objective measures of snoring. Participants had a 1-week in-home sleep posture assessment and a in-home PSG study before being randomised to either CPAP or supine-avoidance therapy for 6-8 weeks, then switched treatments for another 6-8 weeks. Snoring and treatment outcomes were examined in a subgroup of patients with supine dependent snoring. Baseline measurements showed snoring frequency was 48.9 [95% CI 16.7 to 188.7], 26.3 [95% CI 17.0 to 106.3], 57.5 [95% CI 16.8 to 190.7] snores/h for the whole group, supine snorer and non-supine snorers respectively. Supine sleep as a percentage of total sleep was almost completely abolished with supine-avoidance treatment (Baseline = 30.7% [95% 15.4 to 46.4], supine-avoidance = 0.2% [95% 0.0 to 15.7]). In the whole group, CPAP significantly reduced overall snoring frequency although residual snoring remained. However, no treatment effect was observed with supine-avoidance therapy in reducing snoring frequency (frequency of snores ≥ 50 dBA; baseline = 48.9 [95% 16.7 to 188.7], supine-avoidance = 36.8 [95% 6.3 to 233.7], CPAP = 4.2 [95% 2.1 to 29.5] snores/h). In the sub-group of supine-predominant snorers, supine-avoidance therapy was associated with reduced snoring frequency (Baseline = 26.3 [95% 17.0 to 106.3], supine-avoidance = 14.3 [95% 3.0 to 18.1], CPAP = 4.6 [95% 2.6 to 8.9] snores/h). Supine-avoidance therapy may not necessarily lead to a systematic reduction of snoring frequency in patients with supine-predominant OSA but appears effective in a subgroup of patients.