Positional Sleep Apnea Among Regional and Remote Australian Population and Simulated Positional Treatment Effects

Himanshu Garg; Xin Yi Er; Timothy Howarth; Subash S Heraganahally

doi:10.2147/NSS.S286403

Positional Sleep Apnea Among Regional and Remote Australian Population and Simulated Positional Treatment Effects

Nat Sci Sleep. 2020 Dec 4:12:1123-1135. doi: 10.2147/NSS.S286403. eCollection 2020.

Authors

Himanshu Garg¹, Xin Yi Er¹, Timothy Howarth^{2

3}, Subash S Heraganahally^{1

3

4}

Affiliations

¹ Department of Respiratory and Sleep Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia.
² College of Health and Human Sciences, Charles Darwin University, Darwin, Northern Territory, Australia.
³ Darwin Respiratory and Sleep Health, Darwin Private Hospital, Tiwi, Darwin, Northern Territory, Australia.
⁴ Flinders University - College of Medicine and Public Health, Adelaide, South Australia.

Abstract

Purpose: To assess the prevalence of positional sleep apnea (POSA) and its predictors in patients diagnosed to have obstructive sleep apnea (OSA) in the regional and remote population of the Northern Territory of Australia over a two-year study period (2018 and 2019).

Patients and methods: Of the total 1463 adult patients who underwent a diagnostic polysomnography (PSG), 946 patients were eligible to be included in the study, of them, 810 consecutive patients with OSA (Apnea-Hypopnea Index (AHI) ≥ 5) who slept >4 h and had ≥30 min sleep in both supine and lateral positions were assessed. Patients were considered to have POSA if supine AHI to lateral AHI ratio ≥2. The likely comparative impact of use of continuous positive airway therapy (CPAP) or positional therapy (PT) on disease severity was evaluated using model simulation.

Results: A total of 495/810 (61%) patients had POSA, the majority were males (68% vs 60%, p=0.013) and non-Indigenous Australians (93% vs 87%, p=0.004). POSA patients were younger (mean difference 2.23 years (95% CI 0.27, 4.19)), less obese (BMI mean difference 3.06 (95% CI 2.11, 4.01)), demonstrated less severe OSA (p < 0.001) and a greater proportion reported alcohol consumption (72% vs 62%, p=0.001) as compared to those with non-POSA. Using the simulation model, if patients with POSA use PT two-thirds (323/495, 65%) would obtain significant improvement of their OSA severity, with one in five (92/495, 19%) displaying complete resolution. Comparing this to simulated CPAP therapy, where the majority (444/495, 90%) will show significant improvement, and one-third (162/495, 33%) will display complete resolution.

Conclusion: POSA needs to be routinely recognised and positional therapy integrated in practice especially in the remote regions and in the developing world when effective methods are in place to monitor positional therapy.

Keywords: adherence: apnea hypopnea index; body mass index; continuous positive airway pressure; obstructive sleep apnea; positional therapy.