Neighborhood Green Space and Objective Measures of Sleep: The Multi-Ethnic Study of Atherosclerosis (MESA) Sleep and MESA-Air

Abstract

Background: Sleep-disordered breathing (SDB), including obstructive sleep apnea (OSA), is a prevalent and underdiagnosed condition with significant health and economic consequences. While individual behaviors and environmental exposures are known contributors to poor sleep, the role of neighborhood green space remains underexplored, particularly using objective sleep measures. Methods: This study investigates the association between residential greenness—measured by the Normalized Difference Vegetation Index (NDVI)—and polysomnography (PSG)-measured sleep outcomes in 1,543 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) Sleep Ancillary Study. NDVI was assessed within 30m and 300m buffers around participants' homes to capture immediate environmental and neighborhood-scale exposures, respectively. The primary outcome was moderate to severe OSA (AHI ≥15 events/hour), with secondary outcomes including wake after sleep onset (WASO), proportion of sleep time when arterial oxygen saturation (SaO2) falls below 90% (T90), nadir oxygen saturation (SpO2), and oxygen desaturation index (4% desaturation) events per hour. Results: Fully adjusted models revealed that a one interquartile range increase in annual NDVI within a 300m buffer was associated with a 19% lower prevalence of moderate to severe OSA (PR = 0.81; 95% CI: 0.68, 0.98). Associations at smaller buffer sizes were directionally consistent but not statistically significant. No significant associations were observed for secondary sleep outcomes. Conclusion: These findings suggest that neighborhood-scale greenness may reduce the risk of sleep apnea, potentially through mechanisms involving increased physical activity and reduced environmental stressors. This study underscores the importance of considering spatial scale in sleep and environmental health research and supports the integration of green infrastructure into urban planning to promote sleep health.