Statement of Problem

More than 75% of high school students in the United States are not getting the recommended 8-10 hours of sleep per night. Insufficient sleep is a critical public health concern as it increases risk for cardiovascular disease, hypertension and type 2 diabetes.

Adolescents from low-income urban communities are especially susceptible to not getting enough sleep. Research suggests that neighborhood stressors, such as crime and physical disorder like litter or vacant lots, may also adversely affect adolescent sleep duration and quality. Greater exposure to these stressors often leads adolescents to engage in less physical activity and more sedentary, screen-based activities, which are linked to poor sleep outcomes. In contrast, green space is a protective neighborhood feature that may buffer stress, lower risk of exposure to violence and support healthy sleep, although few studies have examined this association with sleep specifically. In addition, environmental exposures within the home like noise, light and uncomfortable temperatures may also negatively impact sleep. 

While prior studies have focused on where adolescents live, no studies of adolescent sleep have considered neighborhood context dynamically by accounting for all places in which teens spend time. Most urban adolescents spend lots of time outside of their home, limiting our understanding of how their environment impacts sleep. GPS-enabled smartphones offer an innovative opportunity to overcome the limitations of past studies by developing ways to measure adolescent’s total exposure to their neighborhood environments across home, school and other locations where they spend time. We can then gain a better understanding of how environmental factors like crime and greenspace affect teen sleep. Smartphones also allow us to obtain information on a daily basis on home environmental factors that might impact sleep, and we can learn how these factors vary between nights.