PROJECT ABSTRACT
Compared to peers in other racial groups, Black emerging adults (18-28 years old) have the highest risks of
short sleep duration and obesity. This increased risk may be partly explained by greater stress levels resulting
from race-related stress (feelings of discrimination and heightened vigilance) and living in more disadvantaged
home and neighborhood environments. Insufficient sleep (longer sleep-onset latency, shorter sleep duration,
poorer sleep quality and efficiency, less slow-wave sleep, and more severe sleep-disordered breathing) may
also impact obesity risk via several weight-related mechanisms. These include (a) energy balance (difference
between energy intake and energy expenditure), (b) appetite and food reward, (c) cortisol awakening response
and diurnal cortisol profiles, and (d) hydration status. We will prospectively assess effects of insufficient sleep,
race-related stress and living in more disadvantaged home and neighborhood environments on weight-related
mechanisms and obesity markers (body weight, waist circumference and fat mass) in 150 Black emerging adults.
Participants will complete 3, 7-day data collection bursts over 1 year (baseline, 6-month, and 12-month follow-
up). Insufficient sleep variables will be measured with 3 methods: sleep diary, actigraphy and polysomnography.
Self-report and objective methods will be used to assess weight-related mechanisms. Race-related stress will
be self-reported. Home and neighborhood environments (via the Windshield Survey) will be observer-assessed.
Aim 1 will examine prospective effects of insufficient sleep on weight-related mechanisms and obesity markers.
Aim 2 will examine prospective effects of race-related stress and living in more disadvantaged home and
neighborhood environments on insufficient sleep variables, weight-related mechanisms, and obesity markers.
Aim 3 will assess the mediating role of sleep on associations among race-related stress, living in more
disadvantaged home and neighborhood environments, weight-related mechanisms, and obesity markers. Our
overarching hypothesis is that higher amounts of insufficient sleep and race-related stress and living in more
disadvantaged home and neighborhood environments will be associated with (a) greatest energy intake and
positive energy balance, (b) greatest appetite and food reward, (c) flattest diurnal cortisol profiles and lowest
cortisol awakening response, (d) lowest hydration, and (e) greatest weight gain, waist circumference and fat
mass at 1 year. This proposal, led by an Early-Stage Investigator and submitted in response to PAR-20-164
(Mechanisms and Consequences of Sleep Disparities in the U.S.), could have significant public health
implications by identifying how and why insufficient sleep increases obesity risk in Black emerging adults.