A randomized controlled trial of a novel sleep surface for treatment of positional sleep apnea

Background: Positional obstructive sleep apnea (POSA), defined as >50% reduction in the apnea-hypopnea index (AHI) between supine and non-supine positions and a non-supine AHI Objective: To determine whether Graduated Lateral Rotation (GLR) therapy reduces the AHI in those with POSA. Methods: GLR therapy is a sleep surface designed to promote a sleeping position with the upper airway rotated away from a vertical orientation. Twelve subjects with POSA, based on prior clinical polysomnography (PSG), were randomized to sleep on a non-GLR night (N-GLR) followed by GLR night or GLR night followed by N-GLR night in a cross-over design. The PSG scorer was blinded to subject assignment. A random-effects linear regression model was used to establish the relationship between AHI and study parameters which included terms for treatment, sequence, and visit. Results: The AHI difference between GLR and N-GLR nights was -2.66/hr [95% CI: -6.28, 0.95] without any significant effects of sequence and period. No significant differences were found in sleep efficiency (SE), sleep stages and oxygenation indices between the two nights. Six subjects spent less time in supine sleep during the N-GLR night compared to their clinical PSG night. A secondary analysis using data of these subjects from their clinical PSG in the N-GLR night showed an AHI difference of -6.08 [-10.22, -1.95] between GLR and N-GLR nights without any significant differences in SE, sleep stages and oxygenation indices. Conclusions: Compared to nights when POSA subjects spent a longer time in the supine position, sleeping with GLR therapy surface improved the AHI without any change in the sleep architecture.