Racial Disparities in Sleep: Potential Mediation by Discrimination and Psychological Distress.

Previous research has demonstrated that experiences of discrimination contribute to racial disparities in sleep, and that psychological distress mediates these relationships. However, previous research has not included race as part of the mediation pathway and has had limited dimensions of sleep health and psychological mediators. In the current study, we examine serial mediation pathways by which race and sleep health are mediated through discrimination and subsequently through psychological distress (i.e., depressive symptoms, chronic stress, and loneliness). Data were from the 2010 wave of the Health Retirement Study (HRS). The analytic sample (n = 7,749) included Black and White participants who were included in the enhanced face-to-face interview in 2010 and who completed the psychosocial questionnaire. Race was reported as either Black or White. Sleep health was assessed with a 4-item questionnaire. Depressive symptoms were assessed with the shortened CES-D, chronic stress via the ongoing chronic stressor scale, and loneliness via the UCLA loneliness scale. Covariates were included in all serial mediation models. Relative to White participants, Black participants reported increased experiences of discrimination, which was associated with increased psychological distress, and poorer sleep health. Findings demonstrate the significant adverse impact that discrimination has on both psychological well-being and sleep health.

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association.

BACKGROUND: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs). METHODS: The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease. RESULTS: Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics. CONCLUSIONS: The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

The Association of Optimism with Sleep Duration and Quality: Findings from the Coronary Artery Risk and Development in Young Adults (CARDIA) Study.

Optimism is associated with better health outcomes with hypothesized effects due in part to optimism's association with restorative health processes. Limited work has examined whether optimism is associated with better quality sleep, a major restorative process. We test the hypothesis that greater optimism is associated with more favorable sleep quality and duration. Main analyses included adults aged 32-51 who participated in the Coronary Artery Risk Development in Young Adults (CARDIA) study (n = 3,548) during the fifth (Year 15: 2000-2001) and sixth (Year 20: 2005-2006) follow-up visits. Optimism was assessed using the revised Life-Orientation Test. Self-report measures of sleep quality and duration were obtained twice 5 years apart. A subset of CARDIA participants (2003-2005) additionally provided actigraphic data and completed the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Multivariate regression analyses were used to examine associations of optimism and sleep indicators. In cross-sectional analyses of 3548 participants, each standard deviation (SD) higher optimism score resulted in 78% higher odds of self-reporting very good sleep quality. Prospectively, a 1-SD higher optimism score was related to higher odds of reporting persistently good sleep quality across 5-years relative to those with persistently poor sleep [OR = 1.31; 95%CI:1.10,1.56]. In participant with supplementary data, each SD higher optimism score was marginally associated with 22% greater odds of favorable sleep quality [OR = 1.22; 95%CI:1.00,1.49] as measured by the PSQI, with possible mediation by depressive symptoms. Optimism was unrelated to objective actigraphic sleep data. Findings support a positive cross-sectional and prospective association between optimism and self-reported sleep behavior.

The role of race and ethnicity in sleep, circadian rhythms and cardiovascular health.

In recent years, strong evidence has emerged suggesting that insufficient duration, quality, and/or timing of sleep are associated with cardiovascular disease (CVD), and various mechanisms for this association have been proposed. Such associations may be related to endophenotypic features of the sleep homeostat and the circadian oscillator, or may be state-like effects of the environment. Here, we review recent literature on sleep, circadian rhythms and CVD with a specific emphasis on differences between racial/ethnic groups. We discuss the reported differences, mainly between individuals of European and African descent, in parameters related to sleep (architecture, duration, quality) and circadian rhythms (period length and phase shifting). We further review racial/ethnic differences in cardiovascular disease and its risk factors, and develop the hypothesis that racial/ethnic health disparities may, to a greater or smaller degree, relate to differences in parameters related to sleep and circadian rhythms. When humans left Africa some 100,000 years ago, some genetic differences between different races/ethnicities were acquired. These genetic differences have been proposed as a possible predictor of CVD disparities, but concomitant differences in culture and lifestyle between different groups may equally explain CVD disparities. We discuss the evidence for genetic and environmental causes of these differences in sleep and circadian rhythms, and their usefulness as health intervention targets.

The Mediation of Racial Differences in Hypertension by Sleep Characteristics: Chicago Area Sleep Study.

BACKGROUND: Racial disparities in hypertension prevalence in the United States are established. Given our understanding of racial and ethnic disparities in sleep characteristics and demonstrated associations between sleep characteristics and hypertension, we tested whether sleep characteristics mediated racial disparities in hypertension. METHODS: Analyses were performed in the Chicago Area Sleep Study, a population-based cohort study of 154 Blacks, 128 Whites, 103 Hispanics, and 109 Asians without obstructive sleep apnea. Participants underwent 7 days of wrist actigraphy monitoring. Algorithms were used to determine sleep duration and sleep maintenance (the percent of sleep in the sleep period). Hypertension was determined as systolic blood pressure >140mm Hg or diastolic blood pressure >90mm Hg or the use of antihypertensive medications. We estimated sample prevalence ratios for hypertension before and after adjustment for sleep characteristics and also conducted mediation analysis. RESULTS: The sample prevalence of hypertension was highest in Blacks (36%), followed by Hispanics (14%), Asians (8%), and Whites (5%). The sample prevalence ratio for hypertension for Blacks vs. Whites was 5.52 (95% confidence interval (CI): 2.36, 13.23) after adjusting for age, sex, and education. Adjustment for sleep duration had no influence on the effect estimate, but adjustment for sleep maintenance attenuated the sample prevalence ratio to 4.55 (95% CI: 1.91, 11.14). Sleep maintenance mediated 11.4% of the difference in hypertension prevalence between Blacks and Whites in this sample. CONCLUSIONS: Sleep maintenance mediated a small but significant portion of the disparity in hypertension between Blacks and Whites. Future research should investigate the mechanisms underlying these findings.

Disparities in sleep characteristics by race/ethnicity in a population-based sample: Chicago Area Sleep Study.

BACKGROUND: Prior studies report less favorable sleep characteristics among non-Whites as compared with non-Hispanic Whites. However, few population-based studies have used objective measures of sleep duration, especially in more than two racial/ethnic groups. We tested whether objectively estimated sleep duration and self-reported sleep quality varied by race and whether differences were at least partially explained by the variability in clinical, psychological, and behavioral covariates. METHODS: Adults aged 35-64 years who self-identified as White, Black, Asian, or Hispanic were randomly sampled from Chicago, IL, and the surrounding suburbs. Our analytic sample included adults who had an apnea-hypopnea index <15 after one night of screening and who completed seven nights of wrist actigraphy for determination of sleep duration, sleep percentage, minutes of wake after sleep onset, and sleep fragmentation (n = 495). Daytime sleepiness was estimated using the Epworth Sleepiness Scale (ESS), and sleep quality was estimated from the Pittsburgh Sleep Quality Index (PSQI). RESULTS: Following statistical adjustment for age, gender, education, work schedule (ie, day vs. night shift), smoking status, depressive symptoms, body mass index (BMI), hypertension, and diabetes, sleep duration (minutes) was significantly (all p < 0.01) shorter in Black (mean = 399.5), Hispanic (mean = 411.7), and Asian (mean = 409.6) participants than in White participants (mean = 447.4). All remaining sleep characteristics were significantly less favorable among Black participants as compared with White participants. Asian participants also reported significantly more daytime sleepiness than did White participants. CONCLUSIONS: Differences in sleep characteristics by race/ethnicity are apparent in a sample of adults with a low probability of sleep apnea and following adjustment for known confounders.

Sleep disparity, race/ethnicity, and socioeconomic position.

Sleep represents a set of biological functions necessary for the maintenance of life. Performing these functions, though, requires that an individual engage in behaviors, which are affected by social and environmental factors. Race/ethnicity and socioeconomic position represent categories of factors that likely play a role in the experience of sleep in the community. Previous studies have suggested that racial/ethnic minorities and the socioeconomically disadvantaged may be more likely to experience sleep patterns that are associated with adverse health outcomes. It is possible that disparities in sleep represent a pathway by which larger disparities in health emerge. This review (1) contextualizes the concept of race/ethnicity in biomedical research, (2) summarizes previous studies that describe patterns of sleep attainment across race/ethnicity groups, (3) discusses several pathways by which race/ethnicity may be associated with sleep, (4) introduces the potential role of socioeconomic position in the patterning of sleep, and (5) proposes future research directions to address this issue.

Association between sleep deficiency and cardiometabolic disease: implications for health disparities.

BACKGROUND: Cardiometabolic diseases, which include obesity, diabetes, hypertension, and cardiovascular disease, are associated with reduced quality of life and reduced life expectancy. Unfortunately, there are racial/ethnic and socioeconomic disparities associated with these diseases such that minority populations, such as African Americans and Hispanics, and those of lower socioeconomic status, experience a greater burden. Several reports have indicated that there are differences in sleep duration and quality that mirror the disparities in cardiometabolic disease. The goal of this paper is to review the association between sleep and cardiometabolic disease risk because of the possibility that suboptimal sleep may partially mediate the cardiometabolic disease disparities. METHODS: We review both experimental studies that have restricted sleep duration or impaired sleep quality and examined biomarkers of cardiometabolic disease risk, including glucose metabolism and insulin sensitivity, appetite regulation and food intake, and immune function. We also review observational studies that have examined the association between habitual sleep duration and quality, and the prevalence or risk of obesity, diabetes, hypertension, and cardiovascular disease. CONCLUSION: Many experimental and observational studies do support an association between suboptimal sleep and increased cardiometabolic disease risk.

Implications of sleep and energy drink use for health disparities.

The popularity of energy drinks has increased rapidly in the past decade. One of the main reasons people use energy drinks is to counteract effects of insufficient sleep or sleepiness. Risks associated with energy drink use, including those related to sleep loss, may be disproportionately borne by racial minorities and those of lower socioeconomic status. In this review, a brief introduction to the issue of health disparities is provided, population-level disparities and inequalities in sleep are described, and the social-ecological model of sleep and health is presented. Social and demographic patterns of energy drink use are then presented, followed by discussion of the potential ways in which energy drink use may contribute to health disparities, including the following: 1) effects of excessive caffeine in energy drinks, 2) effects of energy drinks as sugar-sweetened beverages, 3) association between energy drinks and risk-taking behaviors when mixed with alcohol, 4) association between energy drink use and short sleep duration, and 5) role of energy drinks in cardiometabolic disease. The review concludes with a research agenda of critical unanswered questions.

Objectively measured sleep characteristics among early-middle-aged adults: the CARDIA study.

Despite mounting evidence that sleep duration is a risk factor across diverse health and functional domains, little is known about the distribution and determinants of sleep. In 2003-2004, the authors used wrist activity monitoring and sleep logs to measure time in bed, sleep latency (time required to fall asleep), sleep duration, and sleep efficiency (percentage of time in bed spent sleeping) over 3 days for 669 participants at one of the four sites of the Coronary Artery Risk Development in Young Adults (CARDIA) study (Chicago, Illinois). Participants were aged 38-50 years, 58% were women, and 44% were Black. For the entire sample, mean time in bed was 7.5 (standard deviation (SD), 1.2) hours, mean sleep latency was 21.9 (SD, 29.0) minutes, mean sleep duration was 6.1 (SD, 1.2) hours, and mean sleep efficiency was 80.9 (SD, 11.3)%. All four parameters varied by race-sex group. Average sleep duration was 6.7 hours for White women, 6.1 hours for White men, 5.9 hours for Black women, and 5.1 hours for Black men. Race-sex differences (p < 0.001) remained after adjustment for socioeconomic, employment, household, and lifestyle factors and for apnea risk. Income was independently associated with sleep latency and efficiency. Sleep duration and quality, which have consequences for health, are strongly associated with race, sex, and socioeconomic status.