Habitual sleep as a contributor to racial differences in cardiometabolic risk

Sleep and Resistant Hypertension

PURPOSE OF REVIEW

The goal of the present review is to describe the current findings on the association of sleep with resistant hypertension (hypertension that remains uncontrolled despite the use of three or more antihypertensive medications from different classes, including a diuretic).

RECENT FINDINGS

Sleep disturbances, particularly obstructive sleep apnea (OSA), are highly prevalent among adults who have resistant hypertension. Randomized controlled trials indicate that treating OSA has modest effects on blood pressure lowering among those with the highest initial blood pressure. There is a paucity of research on the association of habitual sleep and other sleep disturbances with resistant hypertension. Of note, the most recent observational studies describing the association of OSA with resistant hypertension are comprised primarily of non-white race/ethnic groups who are far more likely to have resistant hypertension. OSA is associated with resistant hypertension, but there is limited data on associations between sleep characteristics and resistant hypertension. Future studies should investigate whether treating OSA can reduce disparities in resistant hypertension and whether other aspects of sleep also contribute to resistant hypertension.

Obesity-induced MBD2_v2 expression promotes tumor-initiating triple-negative breast cancer stem cells

Obesity is a risk factor for triple-negative breast cancer (TNBC) incidence and poor outcomes, but the underlying molecular biology remains unknown. We previously identified in TNBC cell cultures that expression of epigenetic reader methyl-CpG-binding domain protein 2 (MBD2), specifically the alternative mRNA splicing variant MBD variant 2 (MBD2_v2), is dependent on reactive oxygen species (ROS) and is crucial for maintenance and expansion of cancer stem cell-like cells (CSCs). Because obesity is coupled with inflammation and ROS, we hypothesized that obesity can fuel an increase in MBD2_v2 expression to promote the tumor-initiating CSC phenotype in TNBC cells in vivo. Analysis of TNBC patient datasets revealed associations between high tumor MBD2_v2 expression and high relapse rates and high body mass index (BMI). Stable gene knockdown/overexpression methods were applied to TNBC cell lines to elucidate that MBD2_v2 expression is governed by ROS-dependent expression of serine- and arginine-rich splicing factor 2 (SRSF2). We employed a diet-induced obesity (DIO) mouse model that mimics human obesity to investigate whether obesity causes increased MBD2_v2 expression and increased tumor initiation capacity in inoculated TNBC cell lines. MBD2_v2 and SRSF2 levels were increased in TNBC cell line-derived tumors that formed more frequently in DIO mice relative to tumors in lean control mice. Stable MBD2_v2 overexpression increased the CSC fraction in culture and increased TNBC cell line tumor initiation capacity in vivo. SRSF2 knockdown resulted in decreased MBD2_v2 expression, decreased CSCs in TNBC cell cultures, and hindered tumor formation in vivo. This report describes evidence to support the conclusion that MBD2_v2 expression is induced by obesity and drives TNBC cell tumorigenicity, and thus provides molecular insights into support of the epidemiological evidence that obesity is a risk factor for TNBC. The majority of TNBC patients are obese and rising obesity rates threaten to further increase the burden of obesity-linked cancers, which reinforces the relevance of this report.

Lifetime discrimination, global sleep quality, and inflammation burden in a multiethnic sample of middle-aged adults

OBJECTIVE

Despite considerable evidence that greater exposure to discrimination over the life course increases risk for systemic inflammation, little is known about the mechanisms responsible for this association. Here we examine the role of global sleep quality as a potential pathway by which self-reported experiences of discrimination contribute to inflammatory dysfunction in a multiethnic sample of middle-aged adults.

METHOD

Participants were 300 adults (36-85 years; 65% women) from Milwaukee, Wisconsin, a subset of the Midlife in the United States Study 2 (2004-2006). Racial/ethnic representation included African American (77.7%), Hispanic (12.7%), Asian/Pacific Islander (5.6%), and Native American (4.0%). Global sleep quality and perceptions of lifetime and daily discrimination were measured by questionnaire. A composite score of inflammation burden was computed as the sum of five markers including C-reactive protein (CRP), interleukin-6 (IL-6), fibrinogen, E-selectin, and intracellular adhesion molecule-1 (ICAM-1).

RESULTS

Greater lifetime exposure to discrimination was associated with higher inflammation burden. This relationship remained significant after adjustments for potential confounding factors, including demographics, medication use, health behaviors, psychological distress, and daily discrimination. Mediation analyses suggested that poor global sleep quality was a key mechanism underlying the link between lifetime discrimination and inflammation burden.

CONCLUSION

These results add to a growing literature on the effects of bias and unfair treatment experienced by people of color and other marginalized groups by demonstrating how such experiences may be particularly consequential for sleep and physiological functioning in midlife. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The Global Problem of Insufficient Sleep and Its Serious Public Health Implications

Good sleep is necessary for good physical and mental health and a good quality of life. Insufficient sleep is a pervasive and prominent problem in the modern 24-h society. A considerable body of evidence suggests that insufficient sleep causes hosts of adverse medical and mental dysfunctions. An extensive literature search was done in all the major databases for “insufficient sleep” and “public health implications” in this review. Globally, insufficient sleep is prevalent across various age groups, considered to be a public health epidemic that is often unrecognized, under-reported, and that has rather high economic costs. This paper addresses a brief overview on insufficient sleep, causes, and consequences, and how it adds to the existing burden of diseases. Insufficient sleep leads to the derailment of body systems, leading to increased incidences of cardiovascular morbidity, increased chances of diabetes mellitus, obesity, derailment of cognitive functions, vehicular accidents, and increased accidents at workplaces. The increased usage of smart phones and electronic devices is worsening the epidemic. Adolescents with insufficient sleep are likely to be overweight and may suffer from depressive symptoms. The paper concludes by emphasizing sleep quality assessments as an important early risk indicator, thereby reducing the incidence of a wide spectrum of morbidities.

Subsidized Housing and Adult Asthma in Boston, 2010-2015

OBJECTIVES

To examine whether subsidized housing, specifically public housing and rental assistance, is associated with asthma in the Boston, Massachusetts, adult population.

METHODS

We analyzed a pooled cross-sectional sample of 9554 adults taking part in 3 Boston Behavioral Risk Factor Surveillance System surveys from 2010 to 2015. We estimated odds ratios for current asthma in association with housing status (public housing development [PHD] resident, rental assistance [RA] renter, non-RA renter, nonrenter nonowner, homeowner as reference) in logistic regression analyses adjusting for year, age, sex, race/ethnicity, education, and income.

RESULTS

The odds of current asthma were 2.02 (95% confidence interval [CI] = 1.35, 3.03) and 2.34 (95% CI = 1.60, 3.44) times higher among PHD residents and RA renters, respectively, than among homeowners. We observed smoking-related effect modification (interaction P = .04); elevated associations for PHD residents and RA renters remained statistically significant (P < .05) only among ever smokers. Associations for PHD residents and RA renters remained consistent in magnitude in comparison with non-RA renters who were eligible for subsidized housing according to income.

CONCLUSIONS

Public housing and rental assistance were strongly associated with asthma in this large cross-sectional sample of adult Boston residents.

Disparities in Hypertension Among African-Americans: Implications of Insufficient Sleep

PURPOSE OF REVIEW

Sleep deficiency has been proposed as a potential contributor to racial disparities in cardiovascular health. We present contemporary evidence on the unequal burden of insufficient sleep in Blacks/African-Americans and the repercussions for disparate risk of hypertension.

RECENT FINDINGS

The prevalence of insufficient sleep is high and rising and has been recognized as an important cardiovascular risk factor. Presumably due to a constellation of environmental, psychosocial, and individual determinants, these risks appear exacerbated in Blacks/African-Americans, who are more likely to experience short sleep than other ethnic/racial groups. Population-based data suggest that the risk of hypertension associated with sleep deficiency is greater in those of African ancestry. However, there is a paucity of experimental evidence linking short sleep duration to blood pressure levels in African-Americans. Blacks/African-Americans may be more vulnerable to sleep deficiency and to its hypertensive effects. Future research is needed to unequivocally establish causality and determine the mechanism underlying the postulated racial inequalities in sleep adequacy and consequent cardiovascular risk.

Environmental Determinants of Insufficient Sleep and Sleep Disorders: Implications for Population Health

PURPOSE OF REVIEW

Sleep is important for overall health and well-being. Insufficient sleep and sleep disorders are highly prevalent among adults and children and therefore a public health burden, particularly because poor sleep is associated with adverse health outcomes. Emerging evidence has demonstrated that environmental factors at the household- and neighborhood-level can alter healthy sleep. This paper will (1) review recent literature on the environmental determinants of sleep among adults as well as children and adolescents; and (2) discuss the opportunities and challenges for advancing research on the environment and sleep.

RECENT FINDINGS

Epidemiologic research has shown that social features of environments, family, social cohesion, safety, noise, and neighborhood disorder can shape and/or impact sleep patterns; and physical features such as light, noise, traffic, pollution, and walkability can also influence sleep and is related to sleep disorders among adults and children. Prior research has mainly measured one aspect of the environment, relied on self-reported sleep, which does not correlate well with objective measures, and investigated cross-sectional associations. Although most studies are conducted among non-Hispanic white populations, there is growing evidence that indicates that minority populations are particularly vulnerable to the effects of the environment on insufficient sleep and sleep disorders.

SUMMARY

There is clear evidence that environmental factors are associated with insufficient sleep and sleep disorders. However, more research is warranted to evaluate how and which environmental factors contribute to sleep health. Interventions that target changes in the environment to promote healthy sleep should be developed, tested, and evaluated as a possible pathway for ameliorating sleep health disparities and subsequently health disparities.

A Review of the Literature Regarding Sleep and Cardiometabolic Disease in African Descent Populations

In the twenty-first century, African descent populations on both the continent of Africa and throughout the world are experiencing a high rate of both sleep disturbances and cardiometabolic diseases. The most common sleep disturbances are reduced sleep duration, insomnia, disordered circadian rhythm, and obstructive sleep apnea. Cardiometabolic diseases include hypertension, coronary artery disease, diabetes, hyperlipidemia, and the metabolic syndrome. This review seeks to call attention to new insights regarding the impact of sleep disturbance on cardiometabolic risk factors and outcomes and then apply these concepts to African descent populations, a relatively understudied population. Initial data suggest disparities in sleep quality may have an important role in current and emerging patterns of cardiometabolic disease for African descent populations both in the United States and abroad.

CLINICALTRIALSGOV IDENTIFIER

Not applicable.