Racial/Ethnic Discrimination and Cardiometabolic Diseases: A Systematic Review

INTRODUCTION

Racial discrimination has been identified as a risk factor for cardiometabolic diseases, the leading cause of morbidity and mortality among racial/ethnic minority groups; however, there is no synthesis of current knowledge on the association between discrimination and cardiometabolic diseases. The objective of this systematic review was to summarize evidence linking racial/ethnic discrimination and cardiometabolic diseases.

METHODS

The review was conducted based on studies identified via electronic searches of 5 databases (PubMed, Google Scholar, WorldWideScience.org, ResearchGate and Microsoft Academic) using terms related to discrimination and cardiometabolic disease.

RESULTS

Of the 123 eligible studies included in the review, 87 were cross-sectional, 25 longitudinal, 8 quasi-experimental, 2 randomized controlled trials and 1 case-control. Cardiometabolic disease outcomes discussed were hypertension (n = 46), cardiovascular disease (n = 40), obesity (n = 12), diabetes (n = 11), metabolic syndrome (n = 9), and chronic kidney disease (n = 5). Although a variety of discrimination measures was employed across the studies, the Everyday Discrimination Scale was used most often (32.5%). African Americans/Blacks were the most frequently studied racial/ethnic group (53.1%), and American Indians the least (0.02%). Significant associations between racial/ethnic discrimination and cardiometabolic disease were found in 73.2% of the studies.

DISCUSSION

Racial/ethnic discrimination is positively associated with increased risk of cardiometabolic disease and higher levels of cardiometabolic biomarkers. Identifying racial/ethnic discrimination as a potential key contributor to the health inequities associated with cardiometabolic diseases is important for addressing the significant burden borne by racial/ethnic minorities.

Childhood environments and their relationship with sleep and ambulatory blood pressure in college students

Objective: Investigate whether psychosocial risk in the childhood family environment moderates the relationship between childhood socioeconomic status (SES) and sleep, and the relationship between childhood SES and ambulatory blood pressure (ABP) in college students, two factors that are linked to future risk for cardiovascular disease. Participants: 124 American college students. Methods: Childhood SES and psychosocial risk in childhood family environments were measured by self-report instruments. Sleep was measured with self-report and actigraphy (over 5 days) and ABP over a 2-day period. Results: Linear regressions adjusting for age, sex, current SES, and current depressive symptoms indicated that SES and psychosocial risk in family environments during childhood interact to inform sleep quality, actigraphy derived wake after sleep onset (WASO), actigraphy derived Sleep Efficiency (SE) and ABP. Conclusions: Psychosocial risk in the childhood family environment may offset previously documented relationships between childhood SES and health-relevant outcomes in college students.

When belongingness backfires: experienced discrimination predicts increased cardiometabolic risk among college students high in social belonging

Research implicates experiences of discrimination in exacerbating cardiometabolic disease (CMD) risk. Belongingness has been suggested as a buffer against the adverse effects of discrimination. However, when discrimination occurs in an environment to which one feels they belong, then the potential benefits of belongingness may dissipate or even exacerbate the effects of discrimination. In the present study, we examined these competing hypotheses on how campus belonging might moderate the relationship between discrimination experienced on campus and CMD risk. College students (n = 160, 60.9% Latino/a/x) reported the frequency of on-campus discrimination and campus belongingness, and then completed items assessing risk for CMD. More frequent discrimination related to higher comparative CMD risk among those who reported high campus belongingness, even after adjusting for relevant covariates. These findings highlight the complicated nature of belongingness in the context of physical health. Future research is needed to better understand the role of environment when considering morbidity among college students.

Association between perceived racial discrimination and hypertension: findings from the ELSA-Brasil study

"Pardos" and blacks in Brazil and blacks in the USA are at greater risk of developing arterial hypertension than whites, and the causes of this inequality are still little understood. Psychosocial and contextual factors, including racial discrimination, are indicated as conditions associated with this inequality. The aim of this study was to identify the association between perceived racial discrimination and hypertension. The study evaluated 14,012 workers from the ELSA-Brazil baseline population. Perceived discrimination was measured by the Lifetime Major Events Scale, adapted to Portuguese. Classification by race/color followed the categories proposed by Brazilian Institute of Geography and Statistics (IBGE). Hypertension was defined by standard criteria. The association between the compound variable - race/racial discrimination - and hypertension was estimated by Poisson regression with robust variance and stratified by the categories of body mass index (BMI) and sex. Choosing white women as the reference group, in the BMI < 25kg/m2 stratum, "pardo" women showed adjusted OR for arterial hypertension of 1.98 (95%CI: 1.17-3.36) and 1.3 (95%CI: 1.13-1.65), respectively, whether or not they experienced racial discrimination. For black women, ORs were 1.9 (95%CI: 1.42-2.62) and 1.72 (95%CI: 1.36-2.18), respectively, for the same categories. Among women with BMI > 25kg/m2 and men in any BMI category, no effect of racial discrimination was identified. Despite the differences in point estimates of prevalence of hypertension between "pardo" women who reported and those who did not report discrimination, our results are insufficient to assert that an association exists between racial discrimination and hypertension.

“I Didn’t Come to School for This”: A Qualitative Examination of Experiences With Race-Related Stressors and Coping Responses Among Black Students Attending a Predominantly White Institution

Exposure to race-related stressors such as discrimination may take a toll on Black undergraduates attending predominantly White institutions (PWIs) who must contend with these stressors in addition to stressors common to the developmental space of emerging adulthood and the transition to college. The aim of this study was to explore Black students’ experiences of race-related stressors, coping responses, and the role of natural mentors (i.e., nonparental adults from students’ preexisting social networks who serve a mentoring role in students’ lives) in the coping process. We conducted semi-structured interviews with Black college students ( n = 12) at a PWI and their natural mentors ( n = 10) with whom they discussed issues related to race. Thematic analysis of data indicated that Black students faced a number of race-related stressors yet employed a set of coping responses including processing the event on one’s own, talking about it with others, and engaging in behavioral strategies such as working harder in school in an effort to disprove negative stereotypes. Findings reflected intentional socialization processes in regard to coping with race-related stressors. We discuss trade-offs associated with identified coping responses and the need for institutional efforts to reduce race-related stressors and foster more inclusive campus environments.

Examining the association between perceived discrimination and heart rate variability in African Americans

OBJECTIVE

Previous research attempting to delineate the role of discrimination in racial/ethnic disparities in hypertension has focused largely on blood pressure, which is chiefly governed by the sympathetic branch of the autonomic nervous system. Consequently, few studies have considered the role of the parasympathetic branch and particularly its regulation of the heart via the vagus nerve.

METHOD

In the present cross-sectional study, we employed hierarchical linear regressions to examine associations between perceived ethnic discrimination and resting heart rate variability (HRV), an important biomarker of parasympathetic cardiac modulation and overall health, in a sample (N = 103) of young, healthy African American participants (58% female, M_age = 19.94 years, SD = 2.84).

RESULTS

After accounting for demographic factors and health status characteristics, lifetime discrimination emerged as an inverse predictor of HRV. When subdomains of discrimination were considered, discrimination attributable to threats or actual acts of aggression was also predictive of lower HRV.

CONCLUSIONS

Our findings suggest that a greater lifetime burden of discrimination and discriminatory harassment and/or assault is associated with lower resting HRV in African Americans. The implications of these findings are discussed in the context of past, present and emerging research emphasizing biological linkages between discrimination and health. (PsycINFO Database Record

Racial Discrimination and Stigma Consciousness Are Associated with Higher Blood Pressure and Hypertension in Minority Men

OBJECTIVE

We examined whether lifetime racial discrimination and stigma consciousness (expecting to be stigmatized) are associated with blood pressure in minority and White middle-aged and older adult men.

DESIGN

Participants were 1533 men (mean age = 63.2 [SD = 7.9, range = 37.4-89.2]; 12.4 % Black, 7.8 % Hispanic, 2.0 % other) diagnosed with clinically localized prostate cancer. We separately modeled associations between discrimination/stigma consciousness and blood pressure outcomes for minorities and Whites controlling for education, income, employment status, age, marital status, BMI, and recruitment site.

RESULTS

Minorities reported more racial discrimination and stigma consciousness than Whites (ps < .001). For minorities, having experienced more racial discrimination was associated with having higher diastolic blood pressure (B = 0.15, p = .016) and having greater stigma consciousness was associated with greater odds of having hypertension (OR = 1.04, p = .047). Greater stigma consciousness was associated with lower systolic blood pressure in Whites (B = -0.24, p = .012).

CONCLUSION

Discrimination and stigma consciousness are associated with common risk factors for chronic disease and premature death that disproportionately affect minorities. Findings for stigma consciousness suggest that anticipatory vigilance may be impacting minority health.

Perceived Discrimination and Nocturnal Blood Pressure Dipping Among Hispanics: The Influence of Social Support and Race

OBJECTIVE

Little is known about the relationship of perceived racism to ambulatory blood pressure (ABP) in Hispanics. We explored possible associations between ABP nocturnal dipping and perceived racism in a Hispanic cohort.

METHODS

Participants included 180 community-dwelling Hispanics from the Northern Manhattan Study. Measures included perceived racism, socioeconomic status, social support, and ABP monitoring. Nocturnal ABP nondipping was defined as a less than 10% decline in the average asleep systolic blood pressure relative to the awake systolic blood pressure.

RESULTS

Overall, 77.8% of participants reported some form of perceived racism (Perceived Ethnic Discrimination Questionnaire scores >1.0). Greater social support was associated with less perceived discrimination (Spearman r = -0.54, p < .001). Those with higher perceived discrimination scores reported more depressive symptoms (r = 0.25, p < .001). Those with higher Perceived Ethnic Discrimination Questionnaire scores were less likely to show nocturnal ABP nondipping in multivariate models (odds ratio = 0.40, confidence interval = 0.17-0.98, p = .045). Among those with low perceived racism, black Hispanic participants were more likely to have nocturnal ABP nondipping (82.6%) compared with white Hispanics (53.9%; p = .02). Among those with high perceived racism, no associations between race and the prevalence of ABP nondipping was found (black Hispanic = 61.5% versus white Hispanic = 51.4%, p = .39; p interaction = .89).

CONCLUSIONS

Perceived racism is relatively common among US Hispanics and is associated with ABP. Nondipping of ABP, a potential cardiovascular risk factor, was more common in black Hispanic participants with low perceived racism. This finding may reflect different coping mechanisms between black versus white Hispanics and related blood pressure levels during daytime exposures to discrimination.

Racism as a Determinant of Health: A Systematic Review and Meta-Analysis

Despite a growing body of epidemiological evidence in recent years documenting the health impacts of racism, the cumulative evidence base has yet to be synthesized in a comprehensive meta-analysis focused specifically on racism as a determinant of health. This meta-analysis reviewed the literature focusing on the relationship between reported racism and mental and physical health outcomes. Data from 293 studies reported in 333 articles published between 1983 and 2013, and conducted predominately in the U.S., were analysed using random effects models and mean weighted effect sizes. Racism was associated with poorer mental health (negative mental health: r = -.23, 95% CI [-.24,-.21], k = 227; positive mental health: r = -.13, 95% CI [-.16,-.10], k = 113), including depression, anxiety, psychological stress and various other outcomes. Racism was also associated with poorer general health (r = -.13 (95% CI [-.18,-.09], k = 30), and poorer physical health (r = -.09, 95% CI [-.12,-.06], k = 50). Moderation effects were found for some outcomes with regard to study and exposure characteristics. Effect sizes of racism on mental health were stronger in cross-sectional compared with longitudinal data and in non-representative samples compared with representative samples. Age, sex, birthplace and education level did not moderate the effects of racism on health. Ethnicity significantly moderated the effect of racism on negative mental health and physical health: the association between racism and negative mental health was significantly stronger for Asian American and Latino(a) American participants compared with African American participants, and the association between racism and physical health was significantly stronger for Latino(a) American participants compared with African American participants. Protocol PROSPERO registration number: CRD42013005464.

Capturing the cardiac effects of racial discrimination: Do the effects "keep going"?

Racial discrimination negatively impacts cardiac functioning, but few studies examine the more distal cardiac effects of racial discrimination experiences. The present study examined the momentary and prolonged impact of lab-based intergroup and intragroup racial discrimination on heart rate variability (HRV) and heart rate (HR) in a sample (N = 42) of African American (AA) women across two days. On day one, the women were exposed to simulated racial discrimination from either a European American (EA) or AA confederate in the lab. On day two, the women returned to the lab for additional physiological recording and debriefing. Women insulted by the EA confederate exhibited lower HRV on day one and marginally lower HRV on day two. These women also exhibited marginally higher HR on day two. The HRV and HR effects on day two were not mediated by differences in perseveration about the stressor. The findings indicate that racial discrimination - particularly intergroup racial discrimination - may have both momentary and prolonged effects on cardiac activity in AAs.

Racial Battle Fatigue for Latina/o Students

Previous literature demonstrates that as a result of racial microaggressions and hostile campus racial climates, Latina/o students often state they experience psychological, physiological, and behavioral stress responses during and after racialized incidents on campuses. The purpose of this study is to quantitatively test the racial battle fatigue framework for Latina/o students using structural equation modeling. Findings suggest that psychological stress responses for Latinas/os are most impacted by racial microaggressions in the racial battle fatigue framework.

Interactive influences of ethnicity, endothelin-1 gene, and everyday discrimination upon nocturnal ambulatory blood pressure

BACKGROUND

Everyday discrimination scale scores are associated with increased ambulatory blood pressure (BP) and reduced nocturnal dipping, and the endothelin-1 (ET-1)/Lys198Asn polymorphism is associated with increased resting BP and exaggerated BP reactivity among African Americans compared to European Americans. Combined influences of these factors on BP control are unknown.

PURPOSE

This study tested the hypothesis of a three-way interaction between ethnicity, ET-1 carrier status, and everyday discrimination upon ambulatory BP and nocturnal dipping.

METHODS

Baseline laboratory anthropometrics and the everyday discrimination scale were completed by 352 (175 African American) young adult normotensives, followed by 24-h ambulatory BP monitoring.

RESULTS

For nocturnal dipping, multiple regression models controlling for age, sex, ethnicity, and body mass index revealed significant three-way ET-1 × everyday discrimination × ethnicity interactions. Specifically, among African American ET-1 T-allele carriers, increases in everyday discrimination led to reduced nocturnal dipping.

CONCLUSIONS

African Americans that carry the ET-1/Lys198Asn T-allele and report higher everyday discrimination scores may be at particular risk for reduced nocturnal dipping.

A Question of Color

This study describes the relative influence of facial skin color, lifetime exposure to racial discrimination, chronic stress, and traditional prehypertension risk factors (family history of hypertension and age) on resting blood pressure and body mass index (BMI) among 196 southern African American (AA) female undergraduate students. Stepwise regression analyses indicated that skin color was the strongest predictor of systolic blood pressure (SBP), diastolic blood pressure (DBP), and BMI. Skin color, chronic stress, and family history of hypertension predicted 53% of the SBP variance. Skin color, chronic stress, and family history of hypertension predicted 30.2% of the DBP variance. Racism and age were not significant predictors of SBP or DBP. Of the variance in BMI, 33% was predicted by skin color, chronic stress, and racism. Age and family history of hypertension were not predictors of BMI. The current study provides evidence of the relationship of skin color and chronic stress to blood pressure among young southern AA women. The study identifies an important relationship between increased racial stress exposure and heavier BMIs, a predictor of prehypertensive risk.

The protective role of racial identity and Africentric worldview in the association between racial discrimination and blood pressure

OBJECTIVE

To examine the protective effects of racial identity and Africentric worldview on the association between racial discrimination and blood pressure (BP).

METHODS

Two hundred ten African American young adults completed questionnaires assessing demographic characteristics, prior racial discrimination experiences, racial identity, and Africentric worldview. Resting BP was assessed before and after completion of the study measures.

RESULTS

Racial discrimination was unrelated to BP in the overall sample (systolic BP, p = .444; diastolic BP [DBP], p = .915; mean arterial pressure, p = .774). However, racial identity and Africentric worldview moderated the association between racial discrimination and BP. Racial discrimination was negatively related to DBP for participants who felt that others viewed African Americans less favorably and who endorsed the uniqueness of the African American experience (B = -2.59, standard error [SE] = 1.29, p = .046). These individuals also had the lowest DBP at high levels of racial discrimination. Racial discrimination was positively associated with DBP for individuals with low levels of Africentric orientation (B = 1.43, SE = 0.72, p = .048) but was unrelated to DBP at moderate (B = 0.24, SE = 0.65, p = .718) and high (B = -0.96, SE = 1.01, p = .341) levels of Africentric worldview.

CONCLUSIONS

Racial and cultural personal characteristics such as racial identity and Africentric orientation may serve an important protective function for BP in African American young adults.

Perceived Racial Discrimination as a Predictor of Health Behaviors: the Moderating Role of Gender

Perceived racial discrimination (PRD) has been implicated in undermining the mental and physical health of racial/ethnic minorities. Researchers have begun to explore the indirect role of health behaviors as one factor in helping to explain this relationship. The goal of the present study was to examine the relationship between PRD and a wide range of health behaviors using a prospective, longitudinal design and to explore the role of gender in moderating these relationships. Using data from the Maryland Adolescent Development in Context Study, we examined the relationship between adolescent PRD (accumulated across ages 14-21) and health behaviors (i.e., diet, substance use, exercise) at age 30 in a sample of middle-class black men and women. Using structural equation modeling, results revealed that more cumulative PRD during adolescence was associated with less healthy eating, more substance use (among men), and more exercise (among women) in young adulthood. Implications of these findings for understanding the role of health behaviors in explaining the link between PRD and health outcomes are considered.

Racism and hypertension: a review of the empirical evidence and implications for clinical practice

BACKGROUND

Despite improved hypertension (HTN) awareness and treatment, racial disparities in HTN prevalence persist. An understanding of the biopsychosocial determinants of HTN is necessary to address racial disparities in the prevalence of HTN. This review examines the evidence directly and indirectly linking multiple levels of racism to HTN.

METHODS

Published empirical research in EBSCO databases investigating the relationships of three levels of racism (individual/interpersonal, internalized, and institutional racism) to HTN was reviewed.

RESULTS

Direct evidence linking individual/interpersonal racism to HTN diagnosis is weak. However, the relationship of individual/interpersonal racism to ambulatory blood pressure (ABP) is more consistent, with all published studies reporting a positive relationship of interpersonal racism to ABP. There is no direct evidence linking internalized racism to BP. Population-based studies provide some evidence linking institutional racism, in the forms of residential racial segregation (RRS) and incarceration, to HTN incidence. Racism shows associations to stress exposure and reactivity as well as associations to established HTN-related risk factors including obesity, low levels of physical activity and alcohol use. The effects vary by level of racism.

CONCLUSIONS

Overall the findings suggest that racism may increase risk for HTN; these effects emerge more clearly for institutional racism than for individual level racism. All levels of racism may influence the prevalence of HTN via stress exposure and reactivity and by fostering conditions that undermine health behaviors, raising the barriers to lifestyle change.

Relationships among perceived racial stress, intolerance of uncertainty, and worry in a black sample

The purpose of this study was to explore the relationships among chronic worry, perceived racial stress, and intolerance of uncertainty in a sample of adults who racially identify as Black. Intolerance of uncertainty has been associated with worry and generalized anxiety disorder in predominantly White samples. Given that racial stress is likely to increase worry, perhaps through the mechanism of intolerance of uncertainty, intolerance of uncertainty was hypothesized to mediate the relationship between perceived racial stress and chronic worry. A nonclinical sample of 77 Black undergraduate students at an urban university completed a series of questionnaires assessing the constructs of interest. Both perceived racial stress and intolerance of uncertainty were significantly correlated with chronic worry in this sample. Moreover, intolerance of uncertainty fully mediated the relationship between perceived racial stress and worry for these Black individuals. These findings are discussed in terms of directions for future research and implications for clinical interventions for Black individuals who are both exposed to racial stress and suffer from chronic worry.

Everyday discrimination and nocturnal blood pressure dipping in black and white americans

OBJECTIVE

To investigate whether an association exists between experiences of everyday discrimination and blood pressure (BP) dipping in a biracial sample of black and white adults. Attenuated nocturnal BP dipping is closely linked to cardiovascular morbidity and mortality. Self-reported experiences of everyday discrimination have also been associated with negative cardiovascular health outcomes.

METHODS

Seventy-eight hypertensive and normotensive women and men (n = 30 black and 48 white) reported on their experiences of everyday discrimination (Everyday Discrimination Scale) and underwent two separate 24-hour ambulatory BP monitoring (ABPM) sessions approximately 1 week apart.

RESULTS

Correlation analysis revealed that higher endorsement of everyday discrimination was significantly associated with less diastolic BP (DBP) and systolic BP (SBP) dipping (p < .05). Subsequent hierarchical regression analyses indicated that everyday discrimination explained 8% to 11% of the variance in SBP and DBP dipping above and beyond other demographic and life-style-related factors, including race, age, 24-hour BP, body mass index, and current socioeconomic status. The relationship between discrimination and dipping was significantly stronger on the second night of monitoring. Finally, analyses revealed that everyday discrimination mediated the relationship between race and BP dipping.

CONCLUSIONS

These findings suggest that experiences of everyday discrimination are associated with less nocturnal SBP and DBP dipping above and beyond the effect of known covariates. The use of multiple ABPM sessions may facilitate the detection of relationships between psychological variables and BP dipping.

Unfair treatment and trait anger in relation to nighttime ambulatory blood pressure in African American and white adolescents

OBJECTIVE

To determine if ambulatory blood pressure (ABP) at night relative to day ABP among adolescents is influenced by unfair treatment and trait anger, and whether these associations are stronger in African Americans and adolescents from lower socioeconomic status (SES) families and neighborhoods.

METHODS

A total of 189 healthy white and African American adolescents (ages = 14-16 years, standard deviation = 0.62, 50% female) completed 2 days and 1 night of ABP monitoring and unfair treatment and trait anger questionnaires. SES was measured using 1) parental education and 2) a composite neighborhood SES score based on U.S. Census tract data for neighborhood poverty and education. The night/day ABP ratio was calculated by dividing the night ABP mean (readings from the self-reported bedtime of each participant through 5 AM) by the day ABP mean (8:30 AM until self-reported bedtime).

RESULTS

Higher trait anger was associated with a higher night/day diastolic blood pressure (DBP) ratio in the full sample, B = 0.003, SE = 0.001, t = 2.20, p = .03. A significant interaction effect for Race x Unfair Treatment on the night/day DBP ratio, B = 0.01, SE = 0.003, t = 3.17, p = .002, followed by post hoc tests indicated that greater unfair treatment was associated with a higher night/day DBP ratio among African Americans, B = 0.006, SE = 0.002, t = 2.56, p = .01. Further, among African American adolescents living in lower SES neighborhoods, greater unfair treatment predicted a higher night/day DBP ratio, B = 0.008, SE = 0.003, t = 3.15, p = .002, and higher trait anger scores predicted a higher night/day DBP ratio, B = 0.008, SE = 0.002, t = 3.19, p = .002.

CONCLUSIONS

Trait anger may be a factor leading to elevated nighttime DBP in both African Americans and whites. Unfair treatment and trait anger are important predictors of elevated night/day ABP ratios among African American adolescents living in lower SES neighborhoods. These factors may contribute to the onset of hypertension in African Americans at a younger age.