A sensor-based study on the environmental determinants of sleep in older adults

The residential environment is hypothesized to influence sleep quality within urban settings. Factors associated with the residential environment include air and noise pollution, area socioeconomic status, green and blue spaces, and other neighborhood features. This study seeks to quantify the association of selected environmental factors with sleep quality in the daily lives of 211 older adults residing in the Paris metropolitan area with sensor-based methods.

Participants' sleep and physical activity were monitored over a 7-day period using 2 accelerometers. Ecological momentary assessment (EMA) surveys were administered 4 times a day to assess depressive and anxiety symptoms. Environmental factors surrounding participants residential addresses, including noise and air pollution, walkability, green and blue space availability, median income, and population density, were computed using geoprocessing methods. Hierarchical mixed models with a random intercept at the individual level were fitted to estimate the adjusted association between residential environmental factors and sleep outcomes [total sleep time (TST), sleep efficiency (SE), and wake after sleep onset (WASO)]. Potential effect modification of or mediation by physical activity and depression and anxiety levels were explored in the analyses.

We observed an effect size of 1.4 more minutes of sleep for each increase of one thousand euro in neighborhood median income (Confidence Intervals: 0.35, 2.45). The average adjusted difference in total sleep time between the 10th and 90th percentiles of neighborhood median income was 23.6 minutes of sleep. Other environmental factors and depression and anxiety levels did not exhibit correlations with sleep outcomes.

The results reveal a positive association between median income at the residential level and TST, while no associations were identified for SE and WASO. In conclusion, these findings underscore the impact of neighborhood socioeconomic status on total sleep time within the context of urban living, highlighting the need for further research.