A systematic comparison of factors that could impact treatment recommendations for patients with Positional Obstructive Sleep Apnea (POSA)

Sleep Med. 2018 Oct;50:145-151. doi: 10.1016/j.sleep.2018.05.012. Epub 2018 May 30.


Objective/background: Systematically compare four criteria for Positional Obstructive Sleep Apnea (POSA) based on AASM 2007 and 2012 hypopnea scoring definitions.

Patients/methods: 142 records acquired by in-home polysomnography (Sleep Profiler PSG2™) were retrospectively analyzed using AHI based on the American Academy Sleep Medicine 2007 and 2012 criteria (AHI2007 and AHI2012). Positional obstructive sleep apnea (POSA) was characterized using four criteria: Amsterdam Positional OSA Classification (APOC), supine AHI twice the non-supine AHI (Cartwright), Cartwright plus the non-supine AHI < 5 (Mador), and the overall AHI severity at least 1.4 times the non-supine severity (Overall/NS-AHI).

Results: Correlations between the Cartwright and Overall/NS-AHI criteria increased with the inclusion of a more relaxed definition of hypopneas (AHI2007 = 0.79 and AHI2012 = 0.86, P < 0.00001). The prevalence of POSA based on the Cartwright and Overall/NS-AHI criteria was approximately 60% in those with at least mild OSA by AHI2007and AHI2012. A 16% reduction in POSA prevalence for AHI2012 vs. AHI2007 was attributed to the increased incident of mild OSA. For identification of those expected to have 25% or 35% reductions in SDB severity with positional therapy, Cartwright and Overall/NS-AHI exhibited the strongest sensitivity and Overall/NS-AHI and Mador the best specificity.

Conclusions: The four criteria used to identify POSA have similarities and differences. While there were similarities between the Cartwright and Overall/NS-AHI criteria in the detection of POSA prevalence across both scoring criteria, the Overall/NS-AHI provided the most consistent detection of those most likely to demonstrate important reductions in sleep disordered breathing severity if supine sleep is avoided.

Keywords: Obstructive sleep apnea; Positional therapy; Prevalence; Sleep disordered breathing; Sleep position; Supine.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Body Mass Index
  • Female
  • Humans
  • Male
  • Middle Aged
  • Polysomnography / methods
  • Posture / physiology*
  • Predictive Value of Tests
  • Prevalence
  • Retrospective Studies
  • Sleep / physiology*
  • Sleep Apnea Syndromes / epidemiology
  • Sleep Apnea Syndromes / physiopathology*
  • Sleep Apnea, Obstructive / classification
  • Sleep Apnea, Obstructive / diagnosis
  • Sleep Apnea, Obstructive / epidemiology
  • Sleep Apnea, Obstructive / physiopathology*
  • Supine Position / physiology*