Positional Obstructive Sleep Apnea Syndrome (POSAS)
Attention for Obstructive Sleep Apnea Syndrome (OSAS) has been growing. More recent – in the last 5 to 10 years – attention for Positional OSAS (POSAS) is increasing as well. The diagnosis POSAS is made when there is a difference between the number of airway blockages if a patient is sleep in supine position compared to sleeping on their belly or on the side. The Dutch guideline Diagnostics and treatment of obstructive sleep apnea (OSA) in adults describes the indication in more detail1. This way of diagnosing POSAS is also referenced as PASS:
- Position related: When the AHI (number of breathing stops per hour) is twice as high in supine position compared to other positions in bed.
- AHI non-supine: It is recommended to select patients with an AHI in side position of ≤10 for an optimal treatment effect. The overall AHI will, almost certain, drop below 10 in this case.234
- Severity: A position trainer is intended for patients with POSA and an AHI between ≥5 and <30.
- Supine sleeping time: Patients need to sleep 10-90% of the time in supine position. Patients that sleep less than 10% of the time in supine position seem to not benefit from the treatment. Patients that sleep 90% of the time in supine position are often also problematic sleepers.
Prevalence of POSAS
The prevalence of POSAS is widely discussed. Various clinical studies mention a prevalence of POSAS between 25,1% and 73,3% of all OSA-patients.56789
Positional sleep apnea is most common in patients with mild or medium OSA with an AHI between ≥5 and <30. Patients with a lower BMI, lower age and smaller neck circumference on average seem to suffer from positional sleep apnea more often.679
1. Nederlandse Vereniging van Artsen voor Longziekten en Tuberculose. (2017) Richtlijn Diagnostiek en behandeling van obstructief slaapapneu (OSA) bij volwassenen, 73-84.
2. van Maanen JP, Meester KA, Dun LN, et al. The sleep position trainer: a new treatment for positional obstructive sleep apnoea. Sleep Breath. 2013;17(2):771–779.
3. van Maanen JP, de Vries N. Long-term effectiveness and compliance of positional therapy with the sleep position trainer in the treatment of positional obstructive sleep apnea syndrome. Sleep. 2014;37(7):1209–1215.
4. Eijsvogel MM, Ubbink R, Dekker J, et al. Sleep position trainer versus tennis ball technique in positional obstructive sleep apnea syndrome. J Clin Sleep Med. 2015;11(2):139–147.
5. Kox D, R. W. (2006, Oct). The role of sleep position in obstructive sleep apnea syndrome. Eur Arch Otorhinolaryngol, 263, 946-50.
6. Vat, H.-R. A. (2013, Sep). Prevalence and predictors of positional sleep apnea in the general population. European Respiratory Journal , 42(57), P3585.
7. Rasmus Rude Laub, K. L. (2015). Prevalence of positional obstructive sleep apnea and patients characteristics using various definitions. European Respiratory Journal (46), PA2372
8. Hendriks, F. B. (2016). European Respiratory Journal (48), PA2327.
9. Bouloukaki, P. S. (2018). Positional obstructive sleep apnea in the European Sleep Apnoea Database (ESADA) study. European Respiratory Journal , 52(62), PA4335