Comparative Effectiveness of Supine Avoidance versus Continuous Positive Airway Pressure for Treating Supine-isolated Sleep Apnea: A Clinical Trial.

Rationale: About 20-35% of patients with obstructive sleep apnea (OSA) have supine-isolated OSA, for which supine sleep avoidance could be an effective therapy. However, traditional supine discomfort-based methods show poor tolerance and compliance to treatment and so cannot be recommended. Supine alarm devices show promise, but evidence to support favorable adherence to treatment and effectiveness at reducing excessive daytime sleepiness compared with continuous positive airway pressure (CPAP) remains limited. Objectives: To establish if alarm-based supine-avoidance treatment in patients with supine-isolated OSA is noninferior to CPAP in reducing daytime sleepiness. Methods: After baseline questionnaire administration and in-home supine-time and polysomnography assessments, patients with supine-isolated OSA and Epworth Sleepiness Scale scores ⩾8 were randomized to ⩾6 weeks of supine-avoidance or CPAP treatment, followed by crossover to the remaining treatment with repeat assessments. Noninferiority was assessed from change in Epworth Sleepiness Scale with supine avoidance compared with CPAP using a prespecified noninferiority margin of 1.5. Average nightly treatment use over all nights and treatment efficacy and effectiveness at reducing respiratory disturbances were also compared between treatments. Results: The reduction in sleepiness score with supine avoidance (mean [95% confidence interval], -1.9 [-2.8 to -1.0]) was noninferior to that with CPAP (-2.4 [-3.3 to -1.4]) (supine avoidance-CPAP difference, -0.4 [-1.3 to 0.6]), and the lower confidence limit did not cross the noninferiority margin of 1.5 (P = 0.021). Average treatment use was higher with supine avoidance compared with CPAP (mean ± standard deviation, 5.7 ± 2.4 vs. 3.9 ± 2.7 h/night; P < 0.001). Conclusions: In patients with supine-isolated OSA, vibrotactile supine alarm device therapy is noninferior to CPAP for reducing sleepiness and shows superior treatment adherence. Clinical trial registered with www.anzctr.org.au (ACTRN 12613001242718).

Accurate position monitoring and improved supine-dependent obstructive sleep apnea with a new position recording and supine avoidance device.

STUDY OBJECTIVES: Approximately 30% of obstructive sleep apnea (OSA) patients have supine-predominant OSA, and simply avoiding supine sleep should normalise respiratory disturbance event rates. However, traditional supine-avoidance therapies are inherently uncomfortable, and treatment adherence is poor and difficult to monitor objectively. This study evaluated the efficacy of a novel, potentially more acceptable position monitor and supine-avoidance device for managing supine-predominant OSA and snoring. DESIGN AND SETTING: In-laboratory evaluation of position recording accuracy versus video recordings (validation study), and randomized controlled crossover trial of active versus inactive supine-avoidance therapy in the home setting (efficacy study). PATIENTS: 17 patients undergoing in-laboratory sleep studies (validation) and 15 patients with supine-predominant OSA (efficacy). INTERVENTIONS: EFFICACY STUDY: 1 week of inactive and 1 week of active treatment in randomized order, separated by 1 week. MEASUREMENTS AND RESULTS: Agreement between 30-sec epoch-based posture classifications from device versus video records was high (median κ 0.95, interquartile range: 0.88-1.00), and there was good supine time agreement (bias 0.3%, 95%CI: -4.0% to 4.6%). In the efficacy study, apnea-hypopnea index (AHI) and snoring frequency were measured in-home using a nasal pressure and microphone based system during inactive and active treatment weeks. The position monitoring and supine alarm device markedly inhibited supine time (mean ± SEM 19.3% ± 4.3% to 0.4% ± 0.3%, p < 0.001) and reduced AHI (25.0 ± 1.7 to 13.7 ± 1.1 events/h, p = 0.030) but not snoring frequency. CONCLUSIONS: This new position monitoring and supine alarm device records sleep position accurately and improves OSA but not snoring in patients with supine-predominant OSA.

Poor long-term patient compliance with the tennis ball technique for treating positional obstructive sleep apnea.

STUDY OBJECTIVES: Little is known regarding long-term patient compliance with the tennis ball technique (TBT), one of the original simple methods of positional therapy (i.e., avoiding the supine posture during sleep) for posture-dependent obstructive sleep apnea patients. The purpose of this study was to investigate long-term patient compliance with TBT. METHODS: A follow-up questionnaire was mailed to all patients prescribed TBT at the Adelaide Institute for Sleep Health between July 2004 and March 2008 (n = 108). RESULTS: Sixty-seven patients replied to the questionnaire. Baseline demographic/clinical characteristics were not significantly different from non-respondents. Among the respondents, follow-up time was (mean +/- SD) 2.5 +/- 1.0 years. Four (6.0%) reported they were still using TBT (group A); 9 (13.4%) were no longer using TBT, claiming to have learned to avoid the supine position during sleep (group B); and 54 (80.6%) were neither using TBT nor avoiding the supine posture (group C). The main reason for ceasing TBT use in group C was that TBT was too uncomfortable (34/54 patients). CONCLUSIONS: Long-term patient compliance with TBT appears to be very poor, with less than 10% of patients reporting continued use (group A) approximately 30 months after prescription. With most TBT non-compliers reporting it to be too uncomfortable, alternative forms of positional therapy appear to be needed.

Insomniacs' perception of wake instead of sleep.

STUDY OBJECTIVES: To establish if insomniacs' underestimation of sleep time is due to reduced ability to discriminate between sleeping and waking states. DESIGN: Two night's home polysomnography were compared to sleep diaries. Five laboratory nights employed a series of recorded questions regarding perception of prior sleep-wake state, which were presented during sustained wake and interrupted Stage 2 and REM sleep. SETTING: Sleep laboratory and participants' homes. PARTICIPANTS: Fourteen insomniacs were compared to 8 good sleepers. Mean age for both groups was 58 years. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: A signal detection theory analysis was applied to participants' responses to questions presented overnight in the laboratory concerning judgement of prior sleep-wake state and confidence in their decision. Insomniacs had reduced sleep-wake discriminability in addition to a greater bias toward reporting prior wakefulness in the laboratory compared to good sleepers. These measures correlated significantly with the degree of underestimation of total sleep and overestimation of wake recorded at home. CONCLUSIONS: Insomniacs' underestimation of total sleep time is the product of prior sleep being misperceived as wake time upon awakening overnight. This misperception may play a role in the perpetuation of insomnia.