The sleep justice study - a prospective cohort study assessing sleep as a cardiometabolic risk factor after incarceration: a protocol paper

BACKGROUND: An estimated 11 million individuals are released from U.S. jails and prisons each year. Individuals with a history of incarceration have higher rates of cardiovascular disease (CVD) events and mortality compared to the general population, especially in the weeks following release from carceral facilities. Healthy sleep, associated with cardiovascular health, is an underexplored factor in the epidemiology of CVD in this population. Incarcerated people may have unique individual, environmental, and institutional policy-level reasons for being sleep deficient. The social and physical environment within carceral facilities and post-release housing may synergistically affect sleep, creating disparities in sleep and cardiovascular health. Since carceral facilities disproportionately house poor and minoritized groups, population-specific risk factors that impact sleep may also contribute to inequities in cardiovascular outcomes. METHODS: This study is ancillary to an ongoing prospective cohort recruiting 500 individuals with known cardiovascular risk factors within three months of release from incarceration, the Justice-Involved Individuals Cardiovascular Disease Epidemiology (JUSTICE) study. The Sleep Justice study will measure sleep health among participants at baseline and six months using three validated surveys: the Pittsburgh Sleep Quality Index (PSQI), the STOP-Bang, and the Brief Index of Sleep Control. In a subsample of 100 individuals, we will assess sleep over the course of one week using wrist actigraphy, a validated objective measure of sleep that collects data on rest-activity patterns, sleep, and ambient light levels. Using this data, we will estimate and compare sleep health and its association with CVD risk factor control in individuals recently released from carceral facilities. DISCUSSION: The incarceration of millions of poor and minoritized groups presents an urgent need to understand how incarceration affects CVD epidemiology. This study will improve our understanding of sleep health among people released from carceral facilities and its potential relationship to CVD risk factor control. Using subjective and objective measures of sleep will allow us to identify unique targets to improve sleep health and mitigate cardiovascular risk in an otherwise understudied population.