Environmental Exposures and Disparities in Sleep Health

Fred Hutchinson Cancer Center, Seattle WA

Investigators

Abstract

PROJECT SUMMARY Sleep deficiency is highly prevalent in the population and there are marked disparities in sleep health such as by non-clinical contributors. Factors driving sleep health disparities are not well understood. Thus, there remains a need to identify novel and potentially modifiable risk factors. There is emerging evidence for the role of solar jetlag and climate vulnerability as novel environmental risk factors in sleep health. Solar jetlag occurs from geographic variation in timing of environmental light exposure due to time zone position. People living in the western vs. eastern position of a time zone are exposed to light later in evening, suppressing melatonin, reducing sleep propensity, and reducing sleep duration due to early awakenings for work or social commitments. Climate vulnerability is characterized by exposure to extreme weather events such as high temperatures that increase the frequency, duration, and/or intensity of exposures to environmental factors (e.g., extreme heat, wildfire smoke). Environmental exposures exacerbated by climate vulnerability may affect sleep through mechanisms of disruptions in sleep thermoregulation and breathing. For this R21, we propose to apply geospatial analytics to conduct the first-ever epidemiologic study on solar jetlag and climate vulnerability to identify new risk factors for sleep health disparities. To date, epidemiologic studies on solar jetlag have used coarse-scale measures, and no sleep epidemiologic studies have examined a comprehensive measure of climate vulnerability. To address these research gaps, we propose to use our new high-resolution geospatial light exposure model for solar jetlag (developed by MPIs, Dr. Trang VoPham and Dr. Matthew Weaver) and the geospatial Climate Vulnerability Index (CVI). We will quantify the associations between solar jetlag and climate vulnerability and sleep duration (Aim 1); quantify the associations between solar jetlag and climate vulnerability and sleep quality (Aim 2); and will investigate the role of solar jetlag and climate vulnerability on sleep health disparities by non-clinical contributors (Aim 3). We will leverage a nationwide study population comprised of 5 waves of surveys among US adults in 2022 (n=24,908 total surveys) (Dr. Weaver was PI of these surveys). This valuable resource includes data on sleep outcomes using validated instruments, demographics, lifestyle, behaviors, comorbidities, and respondent geocoded addresses (latitude and longitude coordinates). We will conduct a state-of-the-science geospatial exposure assessment using a geographic information system (GIS), linking geocoded addresses with the MPIs’ new validated high-resolution geospatial light exposure model for solar jetlag and the geospatial CVI dataset. This innovative interdisciplinary research will contribute to the NHLBI mission through impactful science providing new insights into novel, modifiable, biologically plausible environmental risk factors for sleep health disparities. The study findings will have translational utility through informing targets for intervention to promote sleep health. This R21 holds great promise for advancing research on the environmental epidemiology of sleep health disparities.