Since the supine position worsens obstructive sleep apnea (OSA) by promoting upper airway collapse, patients may avoid supine sleep in order to mitigate its effects. However, the avoidance of supine sleep during polysomnography (PSG) may result in a missed diagnosis of OSA. This study aims to examine the association between the presence/absence of supine sleep and the diagnosis of OSA during PSG.
This cross-sectional analysis of a prospective cohort study analyzed the demographic, anthropometric, and PSG results in 243 patients who underwent PSG for suspected OSA. The crude and adjusted association between the absence/presence of supine sleep and OSA diagnosis during PSG was determined using Pearson Chi-square testing and binary logistic regression model fitting, respectively.
Adult patients suspected of OSA who had no supine sleep during PSG had statistically significant lower odds ratio [crude odds ratio (OR) = 0.26, 95%CI: 0.08, 0.81, p = 0.014] of being diagnosed with OSA compared to those who achieved some supine sleep. This association remained robust despite adjusting for known confounders such as age, BMI, and comorbid coronary heart disease (CHD) [adjusted OR = 0.13, 95%CI: 0.03, 0.48, p = 0.002].
Absence of supine sleep during PSG reduces the odds of an OSA diagnosis, even after adjusting for age, BMI, and CHD. Sleep laboratory policies should consider incorporating protocols that encourage patients to achieve some supine sleep during polysomnography in order to facilitate OSA diagnosis.