David S. Curtis

Racial disparities in the health benefits of educational attainment: a study of inflammatory trajectories among African American and white adults.

Objective The current study examined the prospective effects of educational attainment on proinflammatory physiology among African American and white adults. Methods Participants were 1192 African Americans and 1487 whites who participated in Year 5 (mean [standard deviation] age = 30 [3.5] years), and Year 20 (mean [standard deviation] age = 45 [3.5]) of an ongoing longitudinal study. Initial analyses focused on age-related changes in fibrinogen across racial groups, and parallel analyses for C-reactive protein and interleukin-6 assessed at Year 20. Models then estimated the effects of educational attainment on changes in inflammation for African Americans and whites before and after controlling for four blocks of covariates: a) early life adversity, b) health and health behaviors at baseline, c) employment and financial measures at baseline and follow-up, and d) psychosocial stresses in adulthood. Results African Americans had larger increases in fibrinogen over time than whites (B = 24.93, standard error = 3.24, p < .001), and 37% of this difference was explained after including all covariates. Effects of educational attainment were weaker for African Americans than for whites (B = 10.11, standard error = 3.29, p = .002), and only 8% of this difference was explained by covariates. Analyses for C-reactive protein and interleukin-6 yielded consistent results. Conclusions The effects of educational attainment on inflammation levels were stronger for white than for African American participants. Why African Americans do not show the same health benefits with educational attainment is an important question for health disparities research.

Racial discrimination mediates race differences in sleep problems: A longitudinal analysis.

Objectives: To examine changes in sleep problems over a 1.5-year period among Black or African American (AA) and White or European American (EA) college students and to consider the role of racial discrimination as a mediator of race differences in sleep problems over time. Method: Students attending a large, predominantly White university (N = 133, 41% AA, 57% female, mean age = 18.8, SD = .90) reported on habitual sleep characteristics and experiences of racial discrimination at baseline and follow-up assessments. A latent variable for sleep problems was assessed from reports of sleep latency, duration, efficiency, and quality. Longitudinal models were used to examine race differences in sleep problems over time and the mediating role of perceived discrimination. Covariates included age, gender, parent education, parent income, body mass index, self-rated physical health, and depressive symptoms. Each of the individual sleep measures was also examined separately, and sensitivity analyses were conducted using alternative formulations of the sleep problems measure. Results: AAs had greater increases in sleep problems than EAs. Perceived discrimination was also associated with increases in sleep problems over time and mediated racial disparities in sleep. This pattern of findings was similar when each of the sleep indicators was considered separately and held with alternative sleep problems measures. Conclusions: The findings highlight the importance of racial disparities in sleep across the college years and suggest that experiences of discrimination contribute to group disparities.

Longitudinal health consequences of socioeconomic disadvantage: Examining perceived discrimination as a mediator.

Objective: Foundational theoretical perspectives suggest that socioeconomic disadvantage (SED) increases an individual’s risk of being exposed to unfair treatment or discrimination. However, little empirical attention has been given to the role of perceived discrimination in the SED-health gradient. Addressing this knowledge gap, the current study examined the mediating role of discrimination in the longitudinal association between SED and self-rated health. Method: Participants in the Midlife in the United States (MIDUS) study were followed over 3 waves covering a 17- to 19-year period (N = 6,286; 53% female; 91% White; mean age at baseline = 47 years, SD = 13). SED was assessed from education, occupational prestige, income, and assets; self-rated health was measured at baseline and follow-up assessments. Two measures of discrimination—perceived inequality in work and everyday discrimination—were considered as mediators. Results: Both measures of discrimination emerged as important explanatory variables in the link between SED and health. SED at the baseline assessment was associated with changes in self-rated health over the 17- to 19-year period (B = −.15, p < .001). Measures of discrimination partially mediated this longitudinal association, explaining 22% of the total effect. Exposure to discrimination and its health consequences were also more pronounced at younger ages. Conclusion: Additional research is needed to replicate the findings of this study using objective health measures and to examine possible interventions. Challenging the ideologies and practices that underlie social class–related discrimination, or mitigating its harmful consequences, will both be important approaches to consider.

Habitual sleep as a contributor to racial differences in cardiometabolic risk.

Significance Large differences in cardiovascular disease and diabetes prevalence exist between African American and European American adults. The US federal government has committed to reducing racial disparities in health; however, the precise mechanisms are not well understood. Sleep is one potential behavioral explanation for current racial differences in cardiometabolic conditions. We show that more than one-half of racial differences in cardiometabolic risk can be explained by sleep patterns—namely, less total sleep and lower sleep efficiency among African American than European American adults. Sleep is a malleable health behavior that is linked with characteristics of the social and physical environment and could be an effective target in national efforts to reduce racial health disparities. Insufficient and disrupted sleep is linked with cardiovascular and metabolic dysregulation and morbidity. The current study examines the degree to which differences in sleep between black/African American (AA) and white/European American (EA) adults explain racial differences in cardiometabolic (CMB) disease risk. Total sleep time and sleep efficiency (percent of time in bed asleep) were assessed via seven nights of wrist actigraphy among 426 participants in the Midlife in the United States Study (31% AA; 69% EA; 61% female; mean age = 56.8 y). CMB risk was indexed as a composite of seven biomarkers [blood pressure, waist circumference, hemoglobin A1c (HbA1c), insulin resistance, triglycerides, HDL cholesterol (HDL-C), and C-reactive protein]. Covariates included sociodemographic characteristics and relevant health behaviors. Results indicated that AAs relative to EAs obtained less sleep (341 vs. 381 min) and had lower sleep efficiency (72.3 vs. 82.2%) (P values < 0.001). Further, 41% and 58% of the racial difference in CMB risk was explained by sleep time and sleep efficiency, respectively. In models stratified by sex, race was indirectly associated with CMB risk via sleep time and efficiency only among females (explaining 33% and 65% of the race difference, respectively). Indirect effects were robust to alternative model specifications that excluded participants with diabetes or heart disease. Consideration of sleep determinants and sleep health is therefore needed in efforts to reduce racial differences in CMB disease.

Racial Disparities in Blood Pressure Trajectories of Preterm Children: The Role of Family and Neighborhood Socioeconomic Status

Racial disparities in cardiovascular disease mortality in the United States remain substantial. However, the childhood roots of these disparities are not well understood. In the current study, we examined racial differences in blood pressure trajectories across early childhood in a sample of African-American and European-American low-birth-weight preterm infants. Family and neighborhood socioeconomic status (SES), measured at baseline, were also examined as explanations for subsequent group disparities. Analyses focused on 407 African-American and 264 European-American children who participated in the Infant Health and Development Program, a US longitudinal study of preterm children born in 1985. Blood pressure was assessed on 6 occasions between the ages of 24 and 78 months, in 1987-1992. Across this age range, the average rate of change in both systolic and diastolic blood pressure was greater among African-American children than among European-American children. Neighborhood SES explained 29% and 24% of the racial difference in the average rate of change in systolic and diastolic blood pressure, respectively, whereas family SES did not account for group differences. The findings show that racial differences in blood pressure among preterm children emerge in early childhood and that neighborhood SES accounts for a portion of racial disparities.

Relationship Satisfaction Mediates the Link Between Partner Aggression and Relationship Dissolution The Importance of Considering Severity

Physically and psychologically aggressive behaviors between members of a couple often lead to relationship dissatisfaction and dissolution. The current study utilized data from 346 clinical couples to investigate associations between psychological and moderate physical aggression and relationship dissolution, and whether relationship satisfaction acts as a mediator of these associations. Results from two series of Actor–Partner Interdependence Models (APIMs) were considered in which cases of severe aggression were initially removed from the analytic sample and then were included for secondary analyses. The first series of models showed that dyadic physical aggression was a weak predictor of the male partner’s steps taken to leave the relationship and was not associated with the female’s steps. Dyadic psychological aggression, however, was related to steps taken toward leaving by both partners, accounting for approximately 14% of the variance. Relationship satisfaction mediated associations between physical and psychological partner aggression and steps taken to leave. Findings from the second series of models, including cases of severe aggression, showed a significant association between dyadic physical aggression and the female’s steps toward leaving. Moreover, relationship satisfaction no longer fully mediated associations between psychological or physical aggression and relationship dissolution risk. The importance of considering severity of physical partner aggression in research and clinical practice is discussed.

Resting high-frequency heart rate variability moderates the association between early-life adversity and body adiposity

This study investigates resting high-frequency heart rate variability as a moderator of the association between early-life adversity and two measures of body adiposity. Data were collected from 149 young adults attending a large university in the Midwestern United States (Mage = 18.8 years; 45% black; 55% white; 56% female). Self-reported early-life adversity was associated with greater waist-to-height ratio and body mass index. The strength of these associations was moderated by high-frequency heart rate variability, such that the link was stronger for individuals with lower heart rate variability. Resting high-frequency heart rate variability thus has potential health significance as a biomarker of stress vulnerability.