Perceived Discrimination and Trajectories of C-Reactive Protein: The Jackson Heart Study

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.

Discrimination and Cardiovascular Health in Black Americans: Exploring Inflammation as a Mechanism and Perceived Control as a Protective Factor

OBJECTIVE

Inflammation may be an integral physiological mechanism through which discrimination impacts cardiovascular health and contributes to racial health disparities. Limited research has examined psychosocial factors that protect against the negative effects of discrimination on inflammation. Perceived control is a promising possible protective factor, given that it has been shown to moderate the relationship between other psychosocial stressors and physiological outcomes. This study thus tested whether systemic inflammation mediated the link between discrimination and cardiovascular health and whether perceived control moderated this relationship.

METHODS

Data for this project included 347 non-Hispanic/Latinx Black adults (mean [standard deviation] age = 51.64 [11.24] years; 33% female) taken from the Midlife in the United States study. Perceived control and daily discrimination were assessed via self-report, and inflammation was measured via circulating levels of C-reactive protein (CRP), interleukin-6 (IL-6), fibrinogen, and tumor necrosis factor α. Cardiovascular health was measured by morbidity of cardiovascular conditions: heart disease, hypertension, and/or stroke.

RESULTS

CRP (indirect effect: b = 0.004, 95% confidence interval [CI] = 0.001-0.007) and fibrinogen (indirect effect: b = 0.002, 95% CI = 0.0003-0.005) mediated the link between discrimination and cardiovascular conditions. Perceived control moderated the relationship between discrimination and CRP ( F (1, 293) = 4.58, Δ R2 = 0.013, b = -0.02, SE = 0.01, p = .033). CRP mediated the link between discrimination and cardiovascular conditions only for those who reported low levels of perceived control (Index = -0.003, 95% CI = -0.007 to -0.0001).

CONCLUSION

Findings provide empirical evidence of inflammation as a mechanism linking discrimination to cardiovascular conditions among Black Americans. Additionally, perceived control may be protective. Findings could suggest beliefs about control as a potential intervention target to help reduce the negative effects of discrimination on cardiovascular health among Black Americans.

Discrimination and Inflammation in Adolescents of Color

Background

This study examined how experiences with discrimination relate to inflammation, a key biological pathway in mental and physical illnesses, and whether associations are moderated by gender across two samples of adolescents of color.

Methods

Study 1 was a longitudinal study of 419 African American adolescents assessed on discrimination (ages 19-20), with trajectories of biomarkers of low-grade inflammation (C-reactive protein and soluble urokinase plasminogen activator receptor) measured from ages 25 to 29. Study 2 was a cross-sectional study of 201 eighth graders of color assessed on discrimination and mechanistic indicators of a proinflammatory phenotype: 1) in vitro studies of immune cells' inflammatory cytokine responses to stimuli; 2) in vitro studies of cells' sensitivity to anti-inflammatory agents; 3) circulating numbers of classical monocytes, key cellular drivers of low-grade inflammation; and 4) a composite of six biomarkers of low-grade inflammation.

Results

Interactions of discrimination by gender were found across both studies. In study 1, African American males experiencing high discrimination showed increasing trajectories of soluble urokinase plasminogen activator receptor over time (p < .001). In study 2, adolescent boys of color experiencing greater discrimination evinced a more proinflammatory phenotype: larger cytokine responses to stimuli (p = .003), lower sensitivity to anti-inflammatory agents (p = .003), higher numbers of classical monocytes (p = .008), and more low-grade inflammation (p = .003). No such associations were found in females.

Conclusions

Discrimination is a pressing societal issue that will need to be addressed in efforts to promote health equity. This study suggests that adolescent males of color may be particularly vulnerable to its effects on mental health-relevant inflammatory processes.

Compositional analysis of movement behaviors' association on high-sensitivity c-reactive protein: the Jackson heart study

PURPOSE

Movement behaviors (i.e. physical activity [PA], sedentary behavior [SB], and sleep) are intrinsically codependent, an issue resolved using compositional data analysis (CoDA). High-sensitivity C-reactive protein (hs-CRP) is a nonspecific inflammatory marker positively associated with cardiovascular diseases and affected by movement behaviors. Examine the relation between movement behaviors using CoDA and how time reallocation between two movement behaviors was associated with hs-CRP concentration.

METHODS

The Jackson Heart Study was designed to investigate cardiovascular disease risk factors among African American participants in the Jackson, MS area. PA and sleep were self-reported with SB calculated as the remaining time in the day.

RESULTS

The median untransformed hs-CRP concentration was 0.28 mg·dL^-1 (interquartile range; 0.11, 0.61). Reallocating 15 minutes of PA with SB, the hypothetical change in log hs-CRP concentration was 0.08 mg·dL^-1 (95% CIs; 0.04, 0.11) greater than the average log hs-CRP concentration. Substituting 15 minutes of SB or sleep with PA was associated with a hypothetical change in log hs-CRP concentration difference of -0.05 mg·dL^-1 (-0.08, -0.03) and -0.06 mg·dL^-1 (-0.08, -0.03), respectively. Reallocations between SB and sleep were not associated with the hypothetical difference in log hs-CRP concentration.

CONCLUSIONS

Modeling estimates suggest replacing 15 minutes of SB with PA is associated with lower inflammation.

Associations between perceived discrimination and immune cell composition in the Jackson Heart Study

African American adults suffer disproportionately from several non-communicable and infectious diseases. Among numerous contributing factors, perceived discrimination is considered a stressor for members of historically marginalized groups that contributes to health risk, although biological pathways are incompletely understood. Previous studies have reported associations between stress and both an up-regulation of non-specific (innate) inflammation and down-regulation of specific (adaptive) immunity. While associations between perceived discrimination and markers of inflammation have been explored, it is unclear if this is part of an overall shift that also includes down-regulated adaptive immunity. Relying on a large cross-section of African American adults (n = 3,319) from the Jackson Heart Study (JHS) in Jackson, Mississippi, we tested whether perceived everyday and lifetime discrimination as well as perceived burden from lifetime discrimination were associated with counts of neutrophils (innate), monocytes (innate), lymphocytes (adaptive), and the neutrophil-to-lymphocyte ratio (NLR), derived from complete white blood cell counts with differential. In addition, DNA methylation (DNAm) was measured on the EPIC array in a sub-sample (n = 1,023) of participants, allowing estimation of CD4T, CD8T and B lymphocyte proportions. Unexpectedly, high lifetime discrimination compared to low was significantly associated with lower neutrophils (b : -0.14, [95% CI: -0.24, -0.04]) and a lower NLR (b : -0.15, [95% CI: -0.25, -0.05]) after controlling for confounders. However, high perceived burden from lifetime discrimination was significantly associated with higher neutrophils (b : 0.17, [95% CI: 0.05, 0.30]) and a higher NLR (b : 0.16, [95% CI: 0.03, 0.29]). High perceived burden was also associated with lower lymphocytes among older men, which our analysis suggested might have been attributable to differences in CD4T cells. These findings highlight immune function as a potentially important pathway linking perceived discrimination to health outcomes.

What's Race Got to Do With It? CRP Levels in Immune Mediated Skin Diseases: Considerations for Hidradenitis Suppurativa

Currently, there is a lack of racial/ethnic heterogeneity in research databases, exposing a systematic issue in studies exploring inflammation-mediated diseases, such as hidradenitis suppurativa (HS). HS is a chronic inflammatory skin condition that disrupts normal structure and functioning of terminal hair follicles, resulting in the formation of recurrent abscesses, nodules, and sinus tracts within intertriginous regions. Studies have described higher serum levels of inflammation-mediated C-reactive protein (CRP) in patients with HS, a disease that predominantly affects skin of color (SOC) populations. Herein, we explore the role of CRP levels in the context of HS disease presentation, management, and psychosocial implications in SOC patients to determine existing disparities in research studies.

Evidence for Revising the Adverse Childhood Experiences Screening Tool: a Scoping Review

The relationship between adverse childhood experiences (ACEs) and risky behavior, chronic illness, and premature mortality is well documented. Despite this evidence, screening for ACEs in primary care settings remains limited. Objections to widespread screening include concerns that the original ACE screening tool limited childhood adversities to family and household dysfunction. The purpose of this scoping review is to describe current knowledge for expanding ACEs categories and revising the formatting and scoring of the screening tool. With the assistance of a medical librarian, we used a two-step process to conduct a systematic search in three databases (CINAHL, OVID Medline, PsycINFO). Our aim was to focus on articles that expanded ACE categories and/or revised the scoring or formatting of the ACE tool. Eighteen articles (reporting 19 studies) met criteria. A minimum of two authors extracted the relevant characteristics of the studies independently and conferred to reach agreement. The majority of studies broadened ACEs to include community and systemic categories; three studies revised the formatting or scoring of the ACE tool. Exposure to community violence (ECV) was the most frequently added category (15), followed by economic hardship in childhood (EHC) (13); bullying (10); absence/death of parent or significant others (9); and discrimination (7). This evidence supports the expansion of ACE screening tools for assessment of childhood trauma and timely treatment.

Association Between Occupational Sitting With High Sensitivity C-Reactive Protein: The Jackson Heart Study

Modifiable, behavioral risk factors like occupational sitting may contribute to inflammation, an important cardiovascular risk factor. This study evaluated the association of self-reported occupational sitting with changes in c-reactive protein (CRP) and the role of sex. We examined occupational sitting and baseline CRP levels for 2889 African American participants in the Jackson Heart Study. Four multivariable linear regression models were estimated to determine the association of occupational sitting and CRP. Analyses were conducted in 2020. The mean age was 50.8 years and 61% were female. Participants who reported occupational sitting as “often/always” had CRP levels of 4.9±6.8 mg/L, “sometimes” had levels of 4.8±8.1 mg/L, and “never/seldom” had levels of 4.3±6.8 mg/L. In the unadjusted model, “often/always” engaging in occupational sitting was significantly associated with higher levels of CRP when compared to “never/seldom” ( P < .05). This differed by sex with female participants who reported “often/always” occupational sitting had CRP levels of 6.0±7.6 mg/L compared to only 5.1±6.9 mg/L for “never/seldom.” Neither the overall association nor the female-specific association remained statistically significant in the adjusted models. We found an association between occupational sitting and inflammation, measured by CRP. This association varied by sex but did not remain significant after fully adjusting for covariates.

Psychosocial determinants of cardiovascular events among black Americans with chronic kidney disease or associated risk factors in the Jackson heart study

Background

Individuals with chronic kidney disease (CKD), hypertension (HTN), or diabetes mellitus (DM) are at increased risk for cardiovascular disease (CVD). The extent to which psychosocial factors are associated with increased CVD risk within these individuals is unclear. Black individuals experience a high degree of psychosocial stressors due to socioeconomic factors, environment, racism, and discrimination. We examined the association between psychosocial factors and risk of CVD events among Black men and women with CKD and CKD risk factors in the Jackson Heart Study.

Methods and Results

We identified 1919 participants with prevalent CKD or CKD risk factors at baseline. We used rotated principal component analysis - a form of unsupervised machine learning that may identify constructs not intuitively identified by a person - to describe five groups of psychosocial components (including negative moods, religiosity, discrimination, negative outlooks, and negative coping resources) based on a battery of questionnaires. Multiple imputation by chained equation (MICE) was used to impute missing covariate data. Cox models were used to quantify the association between psychosocial components and incident CVD, defined as a fatal coronary heart disease event, myocardial infarction, cardiac procedure (angiography or revascularization procedure), or stroke. Of the 929 participants in the analysis, 67% were female, 28% were current/former smokers with mean age of 56 years and mean BMI of 33 kg/m². Over a median follow-up of 8 years, 6% had an incident CVD event. In multivariable models, each standard deviation (SD) increase in the religiosity component was associated with an increased hazard for CVD event (hazard ratio [HR] = 1.52, 95% CI: 1.09–2.13).

Conclusions

Religiosity was associated with CVD among participants with prevalent CKD or CKD risk factors. Studies to better understand the mechanisms of this relationship are needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02594-6.

Perceived racism, affectivity, and C-reactive protein in healthy African Americans: Do religiosity and racial identity provide complementary protection?

Perceived racism contributes to cardiovascular disease (CVD) disparities among African Americans. Psychosocial factors that protect against the effects of perceived racism therefore may be reflected by indicators of CVD risk, including C-reactive protein (CRP). The current cross-sectional study examined whether CRP is linked to religiosity and racial identity-two culturally-enshrined individual differences that can protect against the harmful effects of racism. Healthy African Americans completed self-report measures of everyday racism, religious intensity (a measure of the importance of religion/spirituality), and racial centrality (a measure of racial identity strength). We measured positive and negative affectivity as outcomes (N = 534), and we collected a dried bloodspot measure of CRP (N = 118). Religious intensity and racial centrality were independently associated with greater positive affectivity, and interactively associated with negative affectivity and CRP-when perceived racism was high, strongly identified African Americans had significantly higher CRP, but lower negative affectivity, when they were also low in religious intensity. Results highlight that religiosity and racial identity may interactively protect against the effects of racism and may play a role in CVD disparities.