0677 The Effect of Enhanced Indoor Oxygen Level on Blood Oxygen Saturation in Individual with Obstructive Sleep Apnea

Abstract Introduction While the physiological aspects of obstructive sleep apnea (OSA) have been extensively studied, less attention has been given to the role of environmental factors, particularly indoor air quality, in individuals with potential OSA. This study investigates the efficacy of non-invasive environmental strategy—elevating indoor oxygen(O2) levels—as a complementary approach for individuals at potential risk of OSA. Methods We conducted a crossover trial with 20 participants, each undergoing two overnight polysomnography (PSG) tests: a sham control and an intervention night. During the intervention, a point-source oxygen diffusion system (80% purity, 8 L/min) increased indoor O2 concentration. We simultaneously monitored indoor air quality (IAQ) parameters, including O2 and carbon dioxide (CO2), alongside standard PSG and blood oxygen saturation (SpO2) data. Results The intervention significantly increased indoor O2 by a median of 1.4% (p< 0.001). This change demonstrated a strong positive correlation (r=0.76, p< 0.01) with SpO2. Multivariate regression analysis further confirmed that a 1% increase in indoor O2 predicted a 0.5% increase in nocturnal SpO2 after controlling for age, sex, BMI, and baseline OSA severity. Conclusion This study demonstrates that a moderate increase in environmental oxygen can significantly improve nocturnal blood oxygen saturation among individuals with OSA. Our pioneering findings suggest that environmental indoor oxygen enrichment could serve as a simple, non-invasive, and complementary strategy to support sleep health, particularly for those with mild to moderate OSA. Support (if any)