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A significant proportion of patients with obstructive sleep apnea (OSA) have positional OSA, where breathing abnormalities are reduced in a nonsupine sleeping position.
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Positional therapy is an attractive strategy for such patients, especially given the well-known challenges of standard continuous positive airway pressure (CPAP) treatment.
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The traditional “Tennis Ball Technique,” however, failed to achieve widespread adoption due to poor patient tolerance and adherence.
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Recently, more
Positional Therapy for Positional Obstructive Sleep Apnea
Section snippets
Key points
Types of classification of positional obstructive sleep apnea
Presently, there are no universally accepted criteria used to diagnose POSA.
The most common criteria used to diagnose POSA are Cartwright’s1 rule of AHI more than 5 per hour and a supine apnea index being at least twice that of nonsupine apnea index, published in 1984.
In 2005, Mador and colleagues5 modified the definition of POSA. Although he too defined POSA as a total AHI more than 5 per hour with a more than 50% reduction in the nonsupine AHI when compared with the supine AHI, he further
Clinical characteristics
Patients with POSA have certain distinctive clinical characteristics that differ from patients with nonpositional OSA. Patients with POSA tend to be younger, have a lower body mass index (BMI), a smaller neck and waist circumference, as well as a lower prevalence of hypertension. They also score lower in Mallampati scores, Berlin questionnaires, STOP questionnaires, and Epworth Sleepiness Scale (ESS). When comparing polysomnographic data with patients with nonpositional OSA, patients with POSA
Pathogenesis
The pharyngeal critical closing pressure (PCrit) measures the pressure at which the upper airway collapses. A higher PCrit indicates that an airway is more collapsible. It has been demonstrated that PCrit is higher in the supine position when compared with the lateral position, indicating a higher collapsibility of the upper airway when supine.9
There are several explanations for the improvement in OSA in the nonsupine position when compared with supine.
Studies have shown that in the supine
What is positional therapy?
PT is defined as any technique used to avoid the worst sleeping position causing POSA. The worst sleeping position usually refers to the supine position.
The tennis ball technique (TBT) is the classic traditional PT in which a tennis ball–sized material is placed in a pocket stitched into the back of a patient’s nightwear. TBT works by causing discomfort when sleeping on the back, forcing the patient to roll into a nonsupine position.
In 1984, a letter written by a patient’s wife describing how
Efficacy of “tennis ball technique” positional therapy
De Vries and colleagues16 evaluated the efficacy of TBT in a single-arm study of 53 patients, in whom 40 patients had a follow-up polysomnogram (PSG) (Table 1). The TBT mimickers included a commercial fabricated waistband as well as self-made constructions in the treatment of POSA. Overall AHI was found to decrease significantly after a median treatment time interval of 12 weeks (median AHI: 14.5–5.9/h, P<.001).
Jackson and colleagues17 compared the use of a sleep position modification device
Positional therapy versus continuous positive airway pressure
Jokic and colleagues22 compared CPAP and PT in 13 patients with POSA in a randomized crossover trial. PT took the form of a soft ball placed in a backpack, a variation of the classic “TBT.” Patients were randomized to either the PT or the CPAP intervention arm for 2 weeks before crossing over to the other arm for another 2 weeks. PT was shown to be effective in reducing sleep time in the supine position. PT was also able to decrease AHI, although a lower AHI was achieved with CPAP. In addition,
Other positional therapy techniques
Techniques other than TBT have been studied over the years. Zuberi and colleagues18 evaluated the efficacy of the SONA pillow in the treatment of 22 subjects with OSA. The SONA pillow was a specially designed inclined pillow that allowed one to place one’s arm under the head while sleeping in a lateral recumbent position. In subjects with mild to moderate OSA, mean Respiratory Disturbance Index (RDI) was shown to decrease significantly from 17 events per hour to less than 5 events per hour
Compliance to traditional positional therapy
Despite its apparent efficacy, PT has not been widely adopted in part due to the poor treatment adherence observed.
In a study by Oksenberg and colleagues,25 TBT compliance was recorded at only 38% (19/50) at 6-month follow-up. In a longer term study by Bignold and colleagues,26 fewer than 10% of patients were using their PT device after 30 months. In a more recent study in 2015 by de Vries and colleagues16 on TBT, although short-term compliance appeared to be good (mean PT usage 7.2 hours per
Limitations of positional therapy trials
Most studies performed with the traditional PT have significant limitations. Many are underpowered, have different definitions of POSA, and different outcome measures. Treatment adherence was mostly measured through subjective reporting by patients, potentially leading to reporting bias. There is also a lack of trials evaluating clinical outcomes with PT therapy in the treatment of POSA. A study by Berger and colleagues21 in 1997 had been the only trial assessing the effect of TBT on blood
New positional therapy devices
Recent technological advances have renewed interest in PT for the treatment of POSA. In the past few years, more sophisticated PT devices have been developed and they appeared to be better than the traditional PT strategies. The new devices are the Night Shift,28 Sleep Position Trainer (SPT),29 and BuzzPOD.30 The small Night Shift device (Fig. 3) is worn at the back of the neck with a latex-free silicone rubber strap that is secured using a magnetic clasp. The SPT (Fig. 4) and BuzzPOD (Fig. 5)
Efficacy of the new positional therapy devices
In 2011, Bignold and colleagues30 first evaluated a novel position monitoring device with an in-built supine avoidance vibratory alarm in a randomized controlled crossover trial of 15 patients with POSA (Table 2). Subjects were randomized to the vibratory positional therapy device or no treatment for 1 week before crossing over to opposite arm after a 1-week washout period. This device significantly reduced mean percentage of supine sleep time and mean AHI (25–13.7 events per hour, P = .03).
In
New positional therapies versus tennis ball technique
In 2015, Eijsvogel and colleagues33 compared the efficacy of the SPT device with that of the traditional TBT in patients with POSA. Both therapies (29 patients in SPT arm and 26 patients in TBT arm) reduced supine sleep position to a median of 0% (minimum-maximum: SPT 0.0% to 67%, TBT 0.0% to 38.9%). Treatment success was defined as AHI less than 5 per hour and appeared to be higher in the SPT group (68.0%) compared with the TBT group (42.9%) although this was not statistically significant.
New positional therapy devices versus continuous positive airway pressure
To date, there are no published data from a randomized controlled trial comparing the new vibratory PT devices with the gold standard CPAP in the treatment of POSA. Three crossover randomized controlled trials are currently ongoing to compare the efficacy of these new vibratory PT devices to CPAP in POSA patients (Table 3).
The POSAtive study (ClinicalTrials.gov: NCT03061071)34 is a multicenter trial in Europe that compares the Nightbalance SPT with autoCPAP. A total of 120 subjects with POSA
New positional therapy devices versus oral appliance therapy
Benoist and colleagues36 recently published their results from a multicenter, prospective randomized controlled trial that compared the SPT with oral appliance therapy (OAT) for the treatment of POSA. In this study, 99 subjects with mild to moderate POSA were randomized to either SPT or OAT for 3 months and 81 subjects completed the study. In the intention-to-treat (ITT) analysis, both SPT and OAT decreased the median AHI (SPT: 13.0–7.0/h, OAT: 11.7–9.1/h) and there were no significant
New positional therapy devices as part of combination therapy
Dieltjens and colleagues37 conducted a crossover randomized controlled trial to evaluate the efficacy of the SPT device in combination with mandibular advancement device (MAD) for the treatment of residual POSA. This study included patients with OSA who had undergone treatment with mandibular advancement device, but demonstrated residual POSA on PSG. The inclusion criteria were a residual AHI between 5 and 50 per hour and a supine AHI ≥2x nonsupine AHI. Of note, another inclusion criterion was
Compliance with the new positional therapy devices
Treatment adherence with the new vibratory positional devices has generally appeared to be high, possibly due to enhanced patient comfort with their petite design. In a study by Van Maanen and colleagues29 using the Sleep Position Trainer, a treatment adherence rate of as high as 92.7% was reported at 1 month. Treatment adherence was defined as more than 4 hours of device use per day during 7 days a week. In the 2 studies by Benoist and colleagues36, 38 mentioned previously, treatment adherence
Summary and future directions
Significant progress in positional therapy has been made with the recent advent of new vibratory PT devices. Studies have demonstrated that these new PT devices are efficacious in reducing overall AHI and better tolerated by patients. Short-term and long-term treatment adherence also appears to be markedly higher compared with traditional positional therapy methods.
Nevertheless, more research is required to determine if the new PT devices can be offered as first-line treatment to patients with
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2022, Brazilian Journal of OtorhinolaryngologyCitation Excerpt :Clinical Research: Randomized controlled trial with snorer patients shows significant reduction in snoring and ESS after 8-weeks.31 Positional therapy is defined as any technique used to avoid problematic sleeping positions, which can cause positional obstructive sleep apnea.32 A couple of sleep positions are available and used for the treatment of Positional Obstructive Sleep Apnea (POSA): Apnea Sleep Position Trainer (Con4m, Hoofddorp, Netherlands).
International Consensus Statement on Obstructive Sleep Apnea
2023, International Forum of Allergy and RhinologyResidual OSA in Down syndrome: does body position matter?
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Disclosure Statement: The authors have no conflict of interests to declare.