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

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 (Cart-wright), 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 ofa more relaxed definition of hypopneas (AH²⁰⁰⁷-0.79 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 AHI²⁰⁰⁷ and AHI²⁰¹². A 16% reduction in POSA prevalence for AHI²⁰¹² vs. AHI²⁰⁰⁷ wasattributed 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