Keith E. Whitfield

Stress, coping, and health outcomes among African-Americans: a review of the John Henryism hypothesis

The John Henryism (JH) hypothesis argues that prolonged high-effort coping with chronic psychosocial stressors may be associated with elevated risk for negative health outcomes among those without sufficient socioeconomic resources. Early JH studies found a significant association between high JH, low socioeconomic status, and hypertension among African-Americans. More recently, these findings have been extended to a wide array of health status outcomes, including cardiovascular reactivity, neurohormonal secretion, and negative health behaviors. The present review provides a comprehensive overview of JHs conceptual bases and empirical support. Limitations of the construct are discussed and recommendations are made to guide future theoretical and research efforts in the area.

The effect of race and health-related factors on naming and memory. The MacArthur Studies of Successful Aging.

Objectives: The purpose of the analyses was to examine the impact of health-related variables on race differences in neuropsychological functioning (Boston Naming Task). Methods: Using cross-sectional data from the MacArthur Successful Aging Study, the authors examined the relationship of demographic characteristics, health status, health habits, physical functioning, and speed of performance to naming and incidental recall of items from the Boston Naming Task. Participants were 1,175 healthy African American and European American older persons 70 to 79 years old. Results: Regression analyses indicated that although race differences persisted for confrontational naming after controlling for demographic and health factors, there was no effect due to race for incidental recall scores or for savings scores for recall. Discussion: The racial differences found in test performance may reflect differences in cultural appropriateness of the material rather than differences in ability.

Individual differences in aging minorities.

To fully understand the differences present between various ethnic and racial groups, there must be an understanding of the heterogeneity that is represented within a given ethnic/racial group. The purpose of this article is to discuss the importance of an individual differences approach in studying the ethnic diversity of an aging population. Conceptual, methodological, and design issues are discussed with the goal of better understanding the developmental processes of aging minority elderly populations.

Does Intact Pair Status Matter in the Study of African American Twins? The Carolina African American Twin Study of Aging

In twin research, typically both members of a pair must participate. Survivorship of members of intact pairs compared to surviving members of nonintact twin pairs may reflect differences in psychosocial and health factors, and represent a potential selection bias relative to the general population. The purpose of the present study is to examine health, cognition, and well-being among members of African American intact twin pairs compared to individuals from nonintact twin pairs. Data from the Carolina African American Twin Study of Aging (CAATSA) were used for analyses. Subjects ranged in age from 25 to 89 years of age (mean=59.78 years, SD=12.84 years). CAATSA implements a 3-h protocol to collect data on demographics, health, cognition, and well-being. Data from one randomly selected member of each twin pair (N=78) was compared to data from surviving members of nonintact twin pairs (N=52). The results indicated significant differences on 11 of the 39 measures (i.e., age, education, forced expiratory volume, mean standing and sitting systolic and diastolic blood pressures, cognitive impairment score, alpha span, digit symbol, and logical memory). In each case, members of intact twin pairs performed better than surviving members of nonintact twin pairs. After controlling demographic variables, only blood pressures differed between the groups. It appears that using only pairs in research on older African American twins may represent a selection bias in estimating origins of individual variability in cognitive functioning and health but not psychological well-being.

The Influence of Social Support and Health on Everyday Problem Solving in Adult African Americans

The purpose of this study was to examine the relationship between social support, health status, and everyday problem solving in African Americans. The sample included subjects recruited from Baltimore, Maryland. The sample consisted of 249 community-dwelling African American adults, 32% of whom were male, with a sample mean age of 67.8 years ( SD =8.47 years). Variables included: Everyday Problem Solving Test (EPT), social support given and received, physical limitations, counts of chronic illness, smoking, and demographic information. Using stepwise regression, age, education, physical limitations, and social support given were found to be significant predictors of performance on the EPT. Further analysis found support for a partial mediating effect of physical limitations on the relationship between social support and everyday problem solving. The results indicate that there may be differences in the cognitive abilities of those actively involved in social activities.

The Impact of Desegregation on Cognition among Older African Americans.

One of the single most influential factors on current and future cognitive functioning is educational attainment. We examined the influence of educational desegregation on cognitive performance using Horn’s Gf-Gc theory among older African Americans. The data on 197 African Americans included school attendance (desegregated [DS] or segregated [SS]) and the number of years they attended desegregated schools. Using measures of fluid (inductive reasoning and spatial ability) and crystallized (number concept and vocabulary) ability to assess cognition, the results showed that the DS group had significantly higher mean cognitive scores compared to the SS group. After controlling for age, gender, years of education, and years in desegregated schools, however, we found no difference between the DS and SS groups on measures of number concept, inductive reasoning, and general fluid and crystallized abilities but found differences for measures of vocabulary and spatial ability. The results were discussed in relation to differences in schooling and other potential influences over the life course.

Genetic and Environmental In‘uences on Personality in Adult Russian Twins

The present study explored genetic and environmental contributions to personality in a sample of twins participating in the Adult Russian Twin Study (ARTS). Subjects included 79 monozygotic (MZ) and 51 dizygotic (DZ) twin-pairs residing in the metropolitan Moscow area, Russia (mean age 42.2 years). Twins completed self-report questionnaires assessing the personality dimensions of neuroticism, extraversion, monotony avoidance, and impulsivity. For all four dimensions, model-”tting analyses yielded estimates of heritability consistent with previous behavioural genetic findings (h 2 ranging from .49 to .59). Also consistent with previous research is the finding that shared environmental variance is negligible for each dimension. These results suggest that the factors that influence individual differences in personality in the Russian culture do not substantially differ from those that influence personality in more Western cultures.

Relationships Among Education, Age, and Cognitive Functioning in Older African Americans: The Impact of Desegregation

The current study sought to examine whether there were differences in the structure of specific cognitive abilities and their association with age and education in a sample of African American elders with two different early educational experiences. The study was conducted with a sample of 197 community dwelling older adults ranging in age from 50 to 79 years (mean age = 61.50 years, SD = 7.30 years). The sample included 79 individuals who attended a desegregated school at anytime during their formal education, while 118 participants completed their schooling without ever attending a desegregated school. Major results included: (1) typical patterns among cognitive abilities and age as well as years of education were found in the full sample of participants; (2) the pattern of age differences in cognition differed between the two groups. Regarding the latter, the desegregated sample exhibited significant negative age differences for some cognitive abilities, while the segregated group did not. Discussion focuses on the importance of considering the nature of the educational experience when examining cognitive aging in African American elders.

Genes, environment, and race: Quantitative genetic approaches

Understanding the origins of racial health disparities is currently a central focus of health-oriented funding agencies and the health policy community. In particular, the role of genetics in the origin of racial health disparities is receiving growing attention and has been susceptible to considerable misinterpretation. In this article, the authors provide a basic discussion about the concept of genes and race, an introduction to quantitative genetics, and some examples of quantitative genetic analyses of health conditions in an underserved population. The intent is to outline the conceptual limitations of exclusivist views of either environmental or genetic determination and to emphasize the coaction and interaction of genes and environments in health.

Relationships Among Health Factors and Everyday Problem Solving in African Americans.

This study examined whether measures of health status enhance the prediction of performance on everyday problem solving in adult African Americans. The sample consisted of 209 community-dwelling African American adults with a mean age of 66.82 years (SD=7.95). The following variables were included in the analysis: Everyday Problems Test (EPT), summary index of chronic illnesses (cardiovascular disease, hypertension, arthritis, stroke, and diabetes), self-rated health (current health, health in the past month, health compared with others, health compared with 5 years ago), and demographic information. Using hierarchical regression and follow-up communality analysis, the authors found that the number of chronic illnesses and self-rated health as compared with 5 years prior were significant and unique predictors of performance on the EPT but did not account for all of the demographic-related variance. The results indicate that health indices contribute to the variability in everyday cognition in this understudied population.