Life Course Socioeconomic Status and Hypertension in African American Adults: The Jackson Heart Study

BACKGROUND

Limited research has examined the association of life-course socioeconomic status (SES) with hypertension prevalence and incidence in a large cohort of African Americans.

METHODS

Among 4,761 participants from the Jackson Heart Study (JHS), we examined the association of SES indicators with prevalent and incident hypertension. We used multivariable Poisson regression to estimate prevalence ratios (PR, 95% confidence interval-CI) of baseline (2000-2004) hypertension by adult (education, income, occupation, wealth) and childhood (mother's education) SES. Cox proportional hazards regression was used to estimate hazard ratios (HR, 95% CI) of incident hypertension by adult and childhood SES (2005-2013; 7.21 median years of follow-up). We also examined the association of childhood-to-adult SES mobility (parent-to-adult education) with prevalent and incident hypertension. Model 1 adjusted for age and sex. Model 2 added waist circumference, behaviors (smoking, alcohol, physical activity, diet), and diabetes prevalence.

RESULTS

High (vs. low) adult SES measures were associated with a lower prevalence of hypertension, with the exception of having a college degree and upper-middle income (PR: 1.04, 95% CI: 1.01, 1.07; PR: 1.05, 95% CI: 1.01, 1.09, respectively). Higher childhood SES was associated with a lower prevalence and risk of hypertension (PR: 0.83, 95%: CI 0.75, 0.91; HR: 0.76, 95% CI: 0.65, 0.89, respectively). Upward mobility and consistent high SES (vs. consistent low SES) from childhood to adulthood was associated with a greater prevalence, but lower incidence of hypertension.

CONCLUSION

Efforts to prevent hypertension among African Americans should consider childhood and current SES status.

Dietary Potential Renal Acid Load and Risk of Albuminuria and Reduced Kidney Function in the Jackson Heart Study

OBJECTIVE

Diets high in sulfur-rich protein and low in fruit and vegetables affect human acid-base balance adversely and may have a harmful effect on progression of chronic kidney disease (CKD). Little is known about the relationship of participant characteristics, dietary acid load (DAL), and kidney injury in African-Americans with high risk of CKD progression.

DESIGN AND METHODS

We examined the association of DAL with CKD in 3,257 African-Americans aged >20 years in Jackson Heart Study. DAL was measured with nutrient intakes assessed with a food frequency questionnaire, using a model described by Remer and Manz. We tested associations of participant characteristics with DAL using median regression, and associations of DAL with albuminuria (>17 mg/g for men, >25 mg/g for women), reduced kidney function (eGFR <60 mL/minute/1.73 m²), or CKD defined as albuminuria or reduced kidney function using logistic regression. We further explored whether endothelin and aldosterone production in participants with hypertension mediated risk of albuminuria or reduced kidney function due to the intake of an acid-inducing diet.

RESULTS

Younger adults, men, and those with higher body mass index had higher DAL. Higher DAL, compared with lower, was associated with greater odds of reduced kidney function (OR [95% CI]: 2.82 [1.40-4.75]). Higher DAL was also associated with greater risk of CKD, and this persisted after adjustment for confounders. Results were similar in adults with hypertension; the OR [95% CI] for highest, versus lowest, tertile of DAL with albuminuria was 1.66 [1.01-2.59]. Aldosterone and endothelin mediated the association between DAL and albuminuria; the OR [95% CI] in the highest tertile was no longer significant 1.53 [0.97-2.40] after their inclusion.

CONCLUSIONS

Higher DAL was associated with higher prevalence of CKD and with reduced kidney function. DAL may be an important target for future interventions in African-Americans at high risk of CKD.

Psychosocial Factors and Behaviors in African Americans: The Jackson Heart Study

INTRODUCTION

There are limited reports on the association of psychosocial factors with unhealthy behaviors, which are key mediators in the psychosocial-cardiovascular disease pathway. The Jackson Heart Study was used to examine the associations of multiple psychosocial factors with behaviors among African Americans.

METHODS

The Jackson Heart Study is a prospective, cohort study of cardiovascular disease among African Americans recruited from the Jackson, MS, metropolitan area between 2000 and 2004. Between 2015 and 2016, multivariable regression was used to analyze the cross-sectional associations of baseline negative affect (cynicism, anger-in, anger-out, and depressive symptoms) and stressors (global stress, Weekly Stress Inventory-event, Weekly Stress Inventory-impact, and major life events) with the odds of current smoking and mean differences in dietary fat intake, physical activity, and hours of sleep.

RESULTS

Men were more likely to smoke than women (p<0.001) and had higher physical activity scores (p<0.001). Women reported more hours of sleep (p=0.001). In fully adjusted models, each negative affect and stress measure was significantly associated with an increased odds of current smoking. For example, the odds of smoking increased by 14% for each 1-SD increase in cynical distrust score (OR=1.14, 95% CI=1.01, 1.27) in the fully adjusted model. Further, each negative affect and stress measure (except anger-out) was significantly associated with fewer hours of sleep in fully adjusted models.

CONCLUSIONS

Using a large sample of African Americans, this study found that multiple psychosocial risk factors were associated with unhealthy behaviors that are prevalent among this population.

Neighborhood social and physical environments and type 2 diabetes mellitus in African Americans: The Jackson Heart Study

Using data from Jackson Heart Study, we investigated the associations of neighborhood social and physical environments with prevalence and incidence of type 2 diabetes mellitus (T2DM) in African Americans (AA). Among non-diabetic participants at baseline (n=3670), 521 (14.2%) developed T2DM during a median follow-up of 7.3 years. Measures of neighborhood social environments, and food and physical activity resources were derived using survey-and GIS-based methods. Prevalence ratios (PR) and Hazard ratios (HR) were estimated using generalized estimating equations and Cox proportional hazards models. Higher neighborhood social cohesion was associated with a 22% lower incidence of T2DM while higher density of unfavorable food stores was associated with a 34% higher incidence of T2DM after adjusting for individual-level risk factors (HR=0.78 [95% CI:0.62, 0.99] and HR=1.34 [1.12, 1.60], respectively). In addition, neighborhood problems was also associated with prevalence of T2DM (PR=1.12 [1.03, 1.21]) independent of individual-level risk factors. Our findings suggest that efforts to strengthen community ties or to attract healthy food retail outlets might be important strategies to consider for prevention of T2DM in AA.

Residential Proximity to Traffic-Related Pollution and Atherosclerosis in 4 Vascular Beds Among African-American Adults: Results From the Jackson Heart Study

To our knowledge, no study has investigated the association of long-term exposure to traffic pollution with markers of atherosclerosis in 4 vascular beds simultaneously in an all-African-American cohort. Among participants in the Jackson Heart Study (Jackson, Mississippi; baseline mean age = 55.5 (standard deviation, 12.7) years), we used linear regression to estimate percent differences in carotid intima-media thickness (CIMT) at baseline (2004) and used modified Poisson regression (robust error variance) to estimate prevalence ratios for peripheral artery disease (PAD), coronary artery calcification (CAC), and abdominal aortic calcification (AAC) at the first follow-up visit (2005-2008) for persons living less than 150 m (versus more than 300 m) from major roadways, adjusting for confounders. Living less than 150 m from such roadways was associated with a significant 6.67% (95% confidence interval: 1.28, 12.35) increase in CIMT (4,800 participants). PAD prevalence among persons living less than 150 m from a major roadway was 1.17 (95% confidence interval: 0.73, 1.86) times that of persons living more than 300 m away (4,443 participants), but this result was not statistically significant. There was no association for CAC or AAC. The association with CIMT was stronger in participants with a cardiovascular disease history than in those without one (P = 0.04). We observed an association in the carotid vascular beds but not the coronary, abdominal, or peripheral vascular beds. Our results highlight the need to consider residential proximity to roadways as a potential cardiovascular disease risk factor for blacks.

Using Community Feedback to Improve Community Interventions: Results From the Deep South Network for Cancer Control Project

The Deep South Network for Cancer Control (DSNCC), initiated in 2000, is a dual-state, community-based participatory research infrastructure composed of academic and community partners committed to reducing cancer disparities among underserved African Americans in 12 designated counties of the Alabama Black Belt and the Mississippi Delta, 2 historically underserved areas of the country. Local residents trained as Community Health Advisors as Research Partners implemented a 3-tier community action plan (CAP) focused on promoting cancer screening, physical activity, and nutrition. Breast, cervical and colorectal cancer screening, healthy eating habits, and physical activity levels increased among many, but not all, African American women in the 12-county DSNCC coverage area. Seeking to improve our reach to include participants who reported they had never heard of the DSNCC or participated in the CAP, we conducted in-depth conversations with community residents about reasons for selective nonparticipation and ways to improve participation in the DSNCC community health interventions. Three patterns and their associated themes described ways to improve the penetration of CAP strategies and tailor them to effectively reach underserved African Americans in the intervention counties. We conclude with lessons learned for future interventions.

Psychosocial Factors Are Associated With Blood Pressure Progression Among African Americans in the Jackson Heart Study

BACKGROUND

Research that examines the associations of psychosocial factors with incident hypertension among African Americans (AA) is limited. Using Jackson Heart Study (JHS) data, we examined associations of negative affect and stress with incident hypertension and blood pressure (BP) progression among AA.

METHODS

Our sample consisted of 1,656 normotensive participants at baseline (2000-2004) (mean age 47±12; 61% women). We investigated associations of negative affect (cynical distrust, anger-in, anger-out, and depressive symptoms) and stress (perceived stress, weekly stress inventory (WSI)-event, WSI-impact, and major life events) with BP progression (an increase by one BP stage as defined by JNC VII) and incident hypertension by examination 2 (2005-2008). Poisson regression analysis was utilized to examine the prevalence ratios (PRs; 95% confidence interval (CI)) of BP tracking and incident hypertension with psychosocial factors, adjusting for baseline age, sex, socioeconomic status (SES), and hypertension risk factors.

RESULTS

Fifty-six percentage of the sample (922 cases) had BP progression from 2005 to 2008. After adjustment for age, sex, and SES, a high anger-out score was associated with a 20% increased risk of BP progression compared to a low anger-out score (PR 1.20; 95% CI 1.05-1.36). High depressive symptoms score was associated with BP progression in the age, sex, and SES-adjusted model (PR 1.14; 95% CI 1.00-1.30). High WSI-event scores were associated with BP progression in the fully adjusted model (PR 1.21; 95% CI 1.04-1.40). We did not observe significant associations with any of the psychosocial measures and incident hypertension.

CONCLUSIONS

Psychosocial factors were associated with BP progression, with the strongest evidence for number of stressful events that occurred.

The National Children's Study: Recruitment Outcomes Using the Provider-Based Recruitment Approach

OBJECTIVE

In 2009, the National Children's Study (NCS) Vanguard Study tested the feasibility of household-based recruitment and participant enrollment using a birth-rate probability sample. In 2010, the NCS Program Office launched 3 additional recruitment approaches. We tested whether provider-based recruitment could improve recruitment outcomes compared with household-based recruitment.

METHODS

The NCS aimed to recruit 18- to 49-year-old women who were pregnant or at risk for becoming pregnant who lived in designated geographic segments within primary sampling units, generally counties. Using provider-based recruitment, 10 study centers engaged providers to enroll eligible participants at their practice. Recruitment models used different levels of provider engagement (full, intermediate, information-only).

RESULTS

The percentage of eligible women per county ranged from 1.5% to 57.3%. Across the centers, 3371 potential participants were approached for screening, 3459 (92%) were screened and 1479 were eligible (43%). Of those 1181 (80.0%) gave consent and 1008 (94%) were retained until delivery. Recruited participants were generally representative of the county population.

CONCLUSIONS

Provider-based recruitment was successful in recruiting NCS participants. Challenges included time-intensity of engaging the clinical practices, differential willingness of providers to participate, and necessary reliance on providers for participant identification. The vast majority of practices cooperated to some degree. Recruitment from obstetric practices is an effective means of obtaining a representative sample.

Overweight and Obesity: Prevalence, Consequences, and Causes of a Growing Public Health Problem

This review considers a variety of perspectives on overweight and obesity (OW/obesity), including measurement and classification; prevalence and changes in prevalence in recent years; genetic, biological, medical, individual, and social correlates of OW/obesity; and treatment approaches. Despite increased attention, OW/obesity is escalating in prevalence worldwide, and the causes are exceedingly complex. A range of innovative studies, including basic research on gut microflora, dietary composition, pharmacologic interventions, and surgical procedures, is generating findings with potential for future prevention and treatment of OW/obesity. Social system changes such as school programs and the awareness of the roles of personal, family, health provider, and cultural experiences related to OW/obesity have also gained traction for vital prevention and treatment efforts over the past decade.

The impact of lifecourse socioeconomic position on cardiovascular disease events in African Americans: the Jackson Heart Study

Background

Few studies have examined the impact of lifecourse socioeconomic position (SEP) on cardiovascular disease (CVD) risk among African Americans.

Methods and Results

We used data from the Jackson Heart Study (JHS) to examine the associations of multiple measures of lifecourse SEP with CVD events in a large cohort of African Americans. During a median of 7.2-year follow-up, 362 new or recurrent CVD events occurred in a sample of 5301 participants aged 21 to 94. Childhood SEP was assessed by using mother’s education, parental home ownership, and childhood amenities. Adult SEP was assessed by using education, income, wealth, and public assistance. Adult SEP was more consistently associated with CVD risk in women than in men: age-adjusted hazard ratios for low versus high income (95% CIs), 2.46 (1.19 to 5.09) in women and 1.50 (0.87 to 2.58) in men, P for interaction=0.1244, and hazard ratio for low versus high wealth, 2.14 (1.39 to 3.29) in women and 1.06 (0.62 to 1.81) in men, P for interaction=0.0224. After simultaneous adjustment for all adult SEP measures, wealth remained a significant predictor of CVD events in women (HR=1.73 [1.04, 2.85] for low versus high). Education and public assistance were less consistently associated with CVD. Adult SEP was a stronger predictor of CVD events in younger than in older participants (HR for high versus low summary adult SEP score 3.28 [1.43, 7.53] for participants ≤50 years, and 1.90 (1.36 to 2.66) for participants >50 years, P for interaction 0.0846). Childhood SEP was not associated with CVD risk in women or men.

Conclusions

Adult SEP is an important predictor of CVD events in African American women and in younger African Americans. Childhood SEP was not associated with CVD events in this population.

Framing body size among African American women and girls

Obesity continues to affect African Americans in epidemic proportions, particularly among women and adolescent females. Perceptions, beliefs, behaviors, and body sizes of adolescents are associated with those of their mothers, yet little is known about the transgenerational meanings and experiences of obese African American adolescent girls and their mothers. An interpretive phenomenological study was conducted with seven African American adolescents between the ages of 11 and 17, and their adult female caregivers. Audio-taped interviews were transcribed and analyzed by a multicultural interpretive team. Two constitutive patterns and associated themes were identified. One pattern, 'Framing: sizing it up; sizing it down', with its three associated themes is presented. Mothers and daughters are engaged in multiple common practices in which they self-define body size, while protecting their self-esteem and self-image. This pattern illustrates how the women and girls created an image of their bodies as they confronted and acknowledged their self-perceptions, compared themselves to others in their environment, and evaluated themselves against specific parameters of acceptable size.

Socioeconomic status, John Henryism and blood pressure among African-Americans in the Jackson Heart Study

John Henryism connotes a strong behavioral predisposition to engage in effortful, active coping with difficult social and economic stressors. This behavioral predisposition is measured by the 12 item John Henryism Scale for Active Coping (JHAC). The John Henry hypothesis predicts that the well-known inverse socioeconomic status (SES)-blood pressure association will be stronger among persons who score high rather than low on the JHAC. We tested this hypothesis in a large African American cohort using baseline data from the Jackson Heart Study. Unlike previous studies, we used multiple indicators of SES: income, education, occupation, childhood SES and cumulative SES. Because the hypothesis is most relevant for adults still in the labor force, we excluded retired participants, yielding a sample size of 3978. Gender-specific Poisson regression models for hypertension adjusting for age, John Henryism, SES, and a John Henryism-SES interaction term, were fit to examine associations. Separate models were fit for each SES indicator. We found some evidence that John Henryism modified the association between income and hypertension in men: low income was associated with higher prevalence of hypertension in men who scored high on John Henryism (prevalence ratio (PR) for low vs. high income tertile 1.12), but with lower hypertension prevalence among men who scored low on John Henryism (PR 0.85, one sided P value for multiplicative interaction <0.05). For women, the association of low income with higher hypertension prevalence was stronger at lower than higher levels of John Henryism (PR 1.27 and 1.06 at low and high levels of John Henryism respectively, P value<0.05). There was no evidence that John Henryism modified the associations of hypertension with other SES indicators in men or women. The modest support of the John Henryism Hypothesis in men only, adds to the literature on this subject, but underscores questions regarding the gender, spatial, socioeconomic and historical contexts in which the hypothesis is valid.

Treatment of hypertension among African Americans: the Jackson Heart Study

Hypertension treatment regimens used by African American adults in the Jackson Heart Study were evaluated at the first two clinical examinations (2415 treated hypertensive persons at examination I [exam I], 2000-2004; 2577 at examination II [exam II], 2005-2008). Blood pressure (BP) was below 140/90 mm Hg for 66% and 70% of treated participants at exam I and exam II, respectively. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure treatment targets were met for 56% and 61% at exam I and exam II, respectively. Persons with diabetes or chronic kidney disease were less likely to have BP at target, as were men compared with women. Thiazide diuretics were the most commonly used antihypertensive medication, and persons taking a thiazide were more likely to have their BP controlled than persons not taking them; thiazides were used significantly less among men than women. Although calcium channel blockers are often considered to be effective monotherapy for African Americans, persons using calcium channel blocker monotherapy were significantly less likely to be at target BP than persons using thiazide monotherapy.

Sleep-disordered breathing symptoms among African-Americans in the Jackson Heart Study

BACKGROUND

Sleep-disordered breathing (SDB) is an increasingly recognized risk factor for cardiovascular disease (CVD). Limited data are available from large African American cohorts.

METHODS

We examined the prevalence, burden, and correlates of sleep symptoms suggestive of SDB and risk for obstructive sleep apnea (OSA) in the Jackson Heart Study (JHS), an all-African-American cohort of 5301 adults. Data on selected daytime and nighttime sleep symptoms were collected using a modified Berlin questionnaire during the baseline examination. Risk of OSA was calculated according to published prediction model. Age and multivariable-adjusted logistic regression models were used to examine the associations between potential risk factors and measures of sleep.

RESULTS

Sleep symptoms, burden, and risk of OSA were high among men and women in the JHS and increased with age and obesity. Being married was positively associated with sleep symptoms among women. In men, poor to fair perceived health and increased levels of stress were associated with higher odds of sleep burden, whereas prevalent hypertension and CVD were associated with higher odds of OSA risk. Similar associations were observed among women with slight variations. Sleep duration <7h was associated with increased odds of sleep symptoms among women and increased sleep burden among men. Moderate to severe restless sleep was consistently and positively associated with odds of adverse sleep symptoms, sleep burden, and high risk OSA.

CONCLUSIONS

Sleep symptoms in JHS had a strong positive association with features of visceral obesity, stress, and poor perceived health. With increasing obesity among younger African Americans, these findings are likely to have broad public health implications.

Sleep-disordered breathing symptoms among African-Americans in the Jackson Heart Study

BACKGROUND

Sleep-disordered breathing (SDB) is an increasingly recognized risk factor for cardiovascular disease (CVD). Limited data are available from large African American cohorts.

METHODS

We examined the prevalence, burden, and correlates of sleep symptoms suggestive of SDB and risk for obstructive sleep apnea (OSA) in the Jackson Heart Study (JHS), an all-African-American cohort of 5301 adults. Data on selected daytime and nighttime sleep symptoms were collected using a modified Berlin questionnaire during the baseline examination. Risk of OSA was calculated according to published prediction model. Age and multivariable-adjusted logistic regression models were used to examine the associations between potential risk factors and measures of sleep.

RESULTS

Sleep symptoms, burden, and risk of OSA were high among men and women in the JHS and increased with age and obesity. Being married was positively associated with sleep symptoms among women. In men, poor to fair perceived health and increased levels of stress were associated with higher odds of sleep burden, whereas prevalent hypertension and CVD were associated with higher odds of OSA risk. Similar associations were observed among women with slight variations. Sleep duration <7h was associated with increased odds of sleep symptoms among women and increased sleep burden among men. Moderate to severe restless sleep was consistently and positively associated with odds of adverse sleep symptoms, sleep burden, and high risk OSA.

CONCLUSIONS

Sleep symptoms in JHS had a strong positive association with features of visceral obesity, stress, and poor perceived health. With increasing obesity among younger African Americans, these findings are likely to have broad public health implications.

The contribution of stress to the social patterning of clinical and subclinical CVD risk factors in African Americans: the Jackson Heart Study

It is often hypothesized that psychosocial stress may contribute to associations of socioeconomic position (SEP) with risk factors for cardiovascular disease (CVD). However, few studies have investigated this hypothesis among African Americans, who may be more frequently exposed to stressors due to social and economic circumstances. Cross-sectional data from the Jackson Heart Study (JHS), a large population-based cohort of African Americans, were used to examine the contributions of stressors to the association of SEP with selected cardiovascular (CVD) risk factors and subclinical atherosclerotic disease. Among women, higher income was associated with lower prevalence of hypertension, obesity, diabetes and carotid plaque and lower levels of stress. Higher stress levels were also weakly, albeit positively, associated with hypertension, diabetes, and obesity, but not with plaque. Adjustment for the stress measures reduced the associations of income with hypertension, diabetes and obesity by a small amount that was comparable to, or larger, than the reduction observed after adjustment for behavioral risk factors. In men, high income was associated with lower prevalence of diabetes and stressors were not consistently associated with any of the outcomes examined. Overall, modest mediation effects of stressors were observed for diabetes (15.9%), hypertension (9.7%), and obesity (5.1%) among women but only results for diabetes were statistically significant. No mediation effects of stressors were observed in men. Our results suggest that stressors may partially contribute to associations of SEP with diabetes and possibly hypertension and obesity in African American women. Further research with appropriate study designs and data is needed to understand the dynamic and interacting effects of stressors and behaviors on CVD outcomes as well as sex differences in these effects.

Social patterning of cumulative biological risk by education and income among African Americans

OBJECTIVES

We examined the social patterning of cumulative dysregulation of multiple systems, or allostatic load, among African Americans adults.

METHODS

We examined the cross-sectional associations of socioeconomic status (SES) with summary indices of allostatic load and neuroendocrine, metabolic, autonomic, and immune function components in 4048 Jackson Heart Study participants.

RESULTS

Lower education and income were associated with higher allostatic load scores in African American adults. Patterns were most consistent for the metabolic and immune dimensions, less consistent for the autonomic dimension, and absent for the neuroendocrine dimension among African American women. Associations of SES with the global allostatic load score and the metabolic and immune domains persisted after adjustment for behavioral factors and were stronger for income than for education. There was some evidence that the neuroendocrine dimension was inversely associated with SES after behavioral adjustment in men, but the immune and autonomic components did not show clear dose-response trends, and we observed no associations for the metabolic component.

CONCLUSIONS

Findings support our hypothesis that allostatic load is socially patterned in African American women, but this pattern is less consistent in African American men.

Perceived discrimination and hypertension among African Americans in the Jackson Heart Study

OBJECTIVES

Using Jackson Heart Study data, we examined whether perceived discrimination was associated with prevalent hypertension in African Americans.

METHODS

Everyday discrimination, lifetime discrimination, burden of discrimination, and stress from discrimination were examined among 4939 participants aged 35 to 84 years (women = 3123; men = 1816). We estimated prevalence ratios of hypertension by discrimination, and adjusted for age, gender, socioeconomic status, and risk factors.

RESULTS

The prevalence of hypertension was 64.0% in women and 59.7% in men. After adjustment for age, gender, and socioeconomic status, lifetime discrimination and burden of discrimination were associated with greater hypertension prevalence (prevalence ratios for highest vs lowest quartile were 1.08 [95% confidence interval (CI) = 1.02, 1.15] and 1.09 [95% CI = 1.02,1.16] for lifetime discrimination and burden of discrimination, respectively). Associations were slightly weakened after adjustment for body mass index and behavioral factors. No associations were observed for everyday discrimination.

CONCLUSIONS

Further understanding the role of perceived discrimination in the etiology of hypertension may be beneficial in eliminating hypertension disparities.

Are religiosity and spirituality associated with obesity among African Americans in the Southeastern United States (the Jackson Heart Study)?

There are several lines of evidence that suggest religiosity and spirituality are protective factors for both physical and mental health, but the association with obesity is less clear. This study examined the associations between dimensions of religiosity and spirituality (religious attendance, daily spirituality, and private prayer), health behaviors and weight among African Americans in central Mississippi. Jackson Heart Study participants with complete data on religious attendance, private prayer, daily spirituality, caloric intake, physical activity, depression, and social support (n = 2,378) were included. Height, weight, and waist circumference were measured. We observed no significant association between religiosity, spirituality, and weight. The relationship between religiosity/spirituality and obesity was not moderated by demographic variables, psychosocial variables, or health behaviors. However, greater religiosity and spirituality were related to lower energy intake, less alcohol use, and less likelihood of lifetime smoking. Although religious participation and spirituality were not cross-sectionally related to weight among African Americans, religiosity and spirituality might promote certain health behaviors. The association between religion and spirituality and weight gain deserves further investigation in studies with a longitudinal study design.

Psychometric testing of the daily spiritual experiences scale among African Americans in the Jackson Heart Study

This study provided the first examination of the psychometric properties of the 6-item Daily Spiritual Experiences Scale (DSES) in a large African American sample, the Jackson Heart Study (JHS). The JHS included measures of spiritual (DSES) and religious practices. Internal reliability, dimensionality, fit indices, and correlation were assessed. DSES scores reflected frequent daily spiritual experiences (12.84 ± 4.72) and reliability scores were high (α = 0.85; 95% CI 0.84-0.86). The DSES loaded on a single factor, with significant goodness-of-fit scores (RMSEA = 0.094, P < 0.01). Moderate significant correlations were noted among DSES items. Our findings confirm that the 6-item DSES had excellent psychometric properties in this sample.

Genome-wide association study for serum urate concentrations and gout among African Americans identifies genomic risk loci and a novel URAT1 loss-of-function allele

Serum urate concentrations are highly heritable and elevated serum urate is a key risk factor for gout. Genome-wide association studies (GWAS) of serum urate in African American (AA) populations are lacking. We conducted a meta-analysis of GWAS of serum urate levels and gout among 5820 AA and a large candidate gene study among 6890 AA and 21 708 participants of European ancestry (EA) within the Candidate Gene Association Resource Consortium. Findings were tested for replication among 1996 independent AA individuals, and evaluated for their association among 28 283 EA participants of the CHARGE Consortium. Functional studies were conducted using (14)C-urate transport assays in mammalian Chinese hamster ovary cells. In the discovery GWAS of serum urate, three loci achieved genome-wide significance (P< 5.0 × 10(-8)): a novel locus near SGK1/SLC2A12 on chromosome 6 (rs9321453, P= 1.0 × 10(-9)), and two loci previously identified in EA participants, SLC2A9 (P= 3.8 × 10(-32)) and SLC22A12 (P= 2.1 × 10(-10)). A novel rare non-synonymous variant of large effect size in SLC22A12, rs12800450 (minor allele frequency 0.01, G65W), was identified and replicated (beta -1.19 mg/dl, P= 2.7 × 10(-16)). (14)C-urate transport assays showed reduced urate transport for the G65W URAT1 mutant. Finally, in analyses of 11 loci previously associated with serum urate in EA individuals, 10 of 11 lead single-nucleotide polymorphisms showed direction-consistent association with urate among AA. In summary, we identified and replicated one novel locus in association with serum urate levels and experimentally characterize the novel G65W variant in URAT1 as a functional allele. Our data support the importance of multi-ethnic GWAS in the identification of novel risk loci as well as functional variants.

The socioeconomic gradient of diabetes prevalence, awareness, treatment, and control among African Americans in the Jackson Heart Study

PURPOSE

Little research has focused on the social patterning of diabetes among African Americans. We examined the relationship between socioeconomic status (SES) and the prevalence, awareness, treatment, and control of diabetes among African Americans.

METHODS

Education, income and occupation were examined among 4,303 participants (2,726 women and 1,577 men). Poisson regression estimated relative probabilities (RP) of diabetes outcomes by SES.

RESULTS

The prevalence of diabetes was 19.6% in women and 15.9% in men. Diabetes awareness, treatment, and control were 90.0%, 86.8%, and 39.2% in women, respectively, and 88.2%, 84.4%, and 35.9% in men, respectively. In adjusted models, low-income men and women had greater probabilities of diabetes than high-income men and women (RP, 1.94; 95% confidence interval [CI], 1.28-2.92; and RP, 1.35; 95% CI, 1.04-1.74, respectively). Lack of awareness was associated with low education and low occupation in women (RP, 2.28; 95%CI 1.01-5.18; and RP, 2.62; 95% CI, 1.08-6.33, respectively) but not in men. Lack of treatment was associated with low education in women. Diabetes control was not patterned by SES.

CONCLUSIONS

Diabetes prevalence is patterned by SES, and awareness and treatment are patterned by SES in women but not men. Efforts to prevent diabetes in African Americans need to address the factors that place those of low SES at higher risk.

Association of genetic variation with systolic and diastolic blood pressure among African Americans: the Candidate Gene Association Resource study

The prevalence of hypertension in African Americans (AAs) is higher than in other US groups; yet, few have performed genome-wide association studies (GWASs) in AA. Among people of European descent, GWASs have identified genetic variants at 13 loci that are associated with blood pressure. It is unknown if these variants confer susceptibility in people of African ancestry. Here, we examined genome-wide and candidate gene associations with systolic blood pressure (SBP) and diastolic blood pressure (DBP) using the Candidate Gene Association Resource (CARe) consortium consisting of 8591 AAs. Genotypes included genome-wide single-nucleotide polymorphism (SNP) data utilizing the Affymetrix 6.0 array with imputation to 2.5 million HapMap SNPs and candidate gene SNP data utilizing a 50K cardiovascular gene-centric array (ITMAT-Broad-CARe [IBC] array). For Affymetrix data, the strongest signal for DBP was rs10474346 (P= 3.6 × 10(-8)) located near GPR98 and ARRDC3. For SBP, the strongest signal was rs2258119 in C21orf91 (P= 4.7 × 10(-8)). The top IBC association for SBP was rs2012318 (P= 6.4 × 10(-6)) near SLC25A42 and for DBP was rs2523586 (P= 1.3 × 10(-6)) near HLA-B. None of the top variants replicated in additional AA (n = 11 882) or European-American (n = 69 899) cohorts. We replicated previously reported European-American blood pressure SNPs in our AA samples (SH2B3, P= 0.009; TBX3-TBX5, P= 0.03; and CSK-ULK3, P= 0.0004). These genetic loci represent the best evidence of genetic influences on SBP and DBP in AAs to date. More broadly, this work supports that notion that blood pressure among AAs is a trait with genetic underpinnings but also with significant complexity.

Associations of fast food restaurant availability with dietary intake and weight among African Americans in the Jackson Heart Study, 2000-2004

OBJECTIVES

We examined the associations of fast food restaurant (FFR) availability with dietary intake and weight among African Americans in the southeastern United States.

METHODS

We investigated cross-sectional associations of FFR availability with dietary intake and body mass index (BMI) and waist circumference in 4740 African American Jackson Heart Study participants (55.2 ± 12.6 years, 63.3% women). We estimated FFR availability using circular buffers with differing radii centered at each participant's geocoded residential location.

RESULTS

We observed no consistent associations between FFR availability and BMI or waist circumference. Greater FFR availability was associated with higher energy intake among men and women younger than 55 years, even after adjustment for individual socioeconomic status. For each standard deviation increase in 5-mile FFR availability, the energy intake increased by 138 kilocalories (confidence interval [CI] = 70.53, 204.75) for men and 58 kilocalories (CI = 8.55, 105.97) for women. We observed similar associations for the 2-mile FFR availability, especially in men. FFR availability was also unexpectedly positively associated with total fiber intake.

CONCLUSIONS

FFR availability may contribute to greater energy intake in younger African Americans who are also more likely to consume fast food.

Age is positively associated with high-density lipoprotein cholesterol among African Americans in cross-sectional analysis: the Jackson Heart Study

BACKGROUND

African Americans have historically had high high-density lipoprotein cholesterol (HDL-C) compared with other races and ethnicities.

OBJECTIVE

We sought to characterize whether there is a cross-sectional association between age and HDL-C in a contemporary community-based study of African Americans.

METHODS

Cross-sectional data were modeled by logistic regression for predictors of HDL-C among African Americans, ages 35-74, participating in the baseline examination of a community-based study of cardiovascular disease in Jackson, Mississippi, during 2000-2004. After excluding persons taking lipid-lowering medications, hormone replacement therapy, oral contraceptives, or thyroid replacement, the analytical data set comprised 2420 persons (1370 women, 1050 men).

RESULTS

HDL-C had a significant positive association with age after controlling for serum triglycerides, sex, waist circumference, percent dietary calories from carbohydrates, alcohol use, and leisure physical activity. Sex was a significant effect modifier of this relationship, whereby the increase in HDL-C with age was steeper for women than for men.

CONCLUSIONS

Cross-sectional analysis found a positive association of HDL-C with age while controlling for triglycerides. Careful evaluation of longitudinal data will be needed to confirm whether this is a true effect of aging, or a cohort or survivor effect.

Geographic representation of the jackson heart study cohort to the African-American population in Jackson, Mississippi

Recent advances in geographic information systems software and multilevel methodology provide opportunities for more extensive characterization of "at-risk" populations in epidemiologic studies. The authors used age-restricted, geocoded data from the all-African-American Jackson Heart Study (JHS), 2000-2004, to demonstrate a novel use of the Lorenz curve and Gini coefficient to determine the representativeness of the JHS cohort to the African-American population in a geographic setting. The authors also used a spatial binomial model to assess the geographic variability in participant recruitment across the Jackson, Mississippi, Metropolitan Statistical Area. The overall Gini coefficient, an equality measure that ranges from 0 (perfect equality) to 1 (perfect inequality), was 0.37 (95% confidence interval (CI): 0.30, 0.45), indicating moderate representation. The population of sampled women (Gini coefficient = 0.34, 95% CI: 0.30, 0.39) tended to be more representative of the underlying population than did the population of sampled men (Gini coefficient = 0.49, 95% CI: 0.35, 0.61). Representative recruitment of JHS participants was observed in predominantly African-American and mixed-race census tracts and in the center of the study area, the area nearest the examination clinic. This is of critical importance as the authors continue to explore novel approaches to investigate the geographic variation in disease etiology.

The triglyceride/high-density lipoprotein cholesterol ratio fails to predict insulin resistance in African-American women: an analysis of Jackson Heart Study

BACKGROUND

Compared to whites, insulin-resistant African Americans have worse outcomes. Screening programs that could identify insulin resistance early enough for intervention to affect outcome often rely on triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels. Racial differences in TG and HDL-C may compromise the efficacy of these programs in African Americans. A recommendation currently exists to use the TG/HDL-C ratio ≥2.0 to predict insulin resistance in African Americans. The validity of this recommendation needs examination. Therefore, our aim was to determine the ability of TG/HDL-C ratio to predict insulin resistance in African Americans.

METHODS

In 1,903 African Americans [895 men, 1,008 women, age 55 ± 12 years, mean ± standard deviation (SD), range 35-80 years, body mass index (BMI) 31.0 ± 6.4 kg/m(2), range 18.5-55 kg/m(2)] participating in the Jackson Heart Study, a population-based study of African Americans, Jackson, Mississippi tricounty region, insulin resistance was defined by the upper quartile (≥4.43) of homeostasis model assessment of insulin resistance (HOMA-IR). An area under the receiver operating characteristic curve (AUC-ROC) of >0.70 was required for prediction of insulin resistance by TG/HDL-C. The optimal test cutoff was determined by the Youden index.

RESULTS

HOMA-IR was similar in men and women (3.40 ± 2.03 vs. 3.80 ± 2.46, P = 0.60). Women had lower TG (94 ± 49 vs. 109 ± 65 mg/dL P < 0.001) and TG/HDL-C (1.9 ± 1.4 vs. 2.7 ± 2.1, P < 0.001). For men, AUC-ROC for prediction of insulin resistance by TG/HDL-C was: 0.77 ± 0.01, mean ± standard error (SE), with an optimal cutoff of ≥2.5. For women, the AUC-ROC was 0.66 ± 0.01, rendering an optimal cutoff indefinable. When women were divided in two groups according to age, 35-50 years and 51-80 years, the results did not change.

CONCLUSIONS

In African-American men, the recommended TG/HDL-C threshold of 2.0 should be adjusted upward to 2.5. In African-American women, TG/HDL-C cannot identify insulin resistance. The Jackson Heart Study can help determine the efficacy of screening programs in African-Americans.

The role of community health advisors in community-based participatory research

Mistrust and fear of research often exist in minority communities because of assumptions, preconceived ideas, and historical abuse and racism that continue to influence research participation. The research establishment is full of well-meaning 'outsider' investigators who recognize discrimination, health disparities, and insufficient health care providers in minority communities, but struggle in breaking through this history of mistrust. This article provides ethical insights from one such 'insider-outsider', community-based participatory research project implemented via community health advisors in the Mississippi Delta. Both community-based participatory research and community health advisors provide opportunities to address the ethical issues of trust, non-maleficence, and justice in minority communities. Implications for ethics-driven nursing research are discussed.

Association of socioeconomic status and CKD among African Americans: the Jackson Heart Study

BACKGROUND

Socioeconomic status (SES) is recognized as a key social environmental factor because it has implications for access to resources that help individuals care for themselves and others. Few studies have examined the association of SES with chronic kidney disease (CKD) in high-risk populations.

STUDY DESIGN

Single-site longitudinal population-based cohort.

SETTING & PARTICIPANTS

Data for this study were drawn from the baseline examination of the Jackson Heart Study. The analytic cohort consisted of 3,430 African American men and women living in the tricounty region of the Jackson, MS, metropolitan area with complete data to determine CKD status.

PREDICTOR

High SES (defined as having a family income at least 3.5 times the poverty level or having at least 1 undergraduate degree).

OUTCOMES & MEASUREMENTS

CKD (defined as the presence of albuminuria or decreased estimated glomerular filtration rate [<60 mL/min/1.73 m(2)]). Associations were explored using bivariable analyses and multivariable logistic regression analyses adjusting for CKD and cardiovascular disease risk factors, as well as demographic factors.

RESULTS

The prevalence of CKD in the Jackson Heart Study was 20% (865 of 3,430 participants). Proportions of the Jackson Heart Study cohort with albuminuria and decreased estimated glomerular filtration rate were 12.5% (429 of 3,430 participants) and 10.1% (347 of 3,430 participants), respectively. High SES was associated inversely with CKD. The odds of having CKD were 41% lower for affluent participants than their less affluent counterparts. There were no statistically significant interactions between sex and education or income, although subgroup analysis showed that high income was associated with CKD in men (OR, 0.47; 95% CI, 0.23-0.97), but not women (OR, 0.64; 95% CI, 0.40-1.03).

LIMITATIONS

Models were estimated using cross-sectional data.

CONCLUSION

CKD is associated with SES. Additional research is needed to elucidate the impact of wealth and social contexts in which individuals are embedded and the mediating effects of sociocultural factors.

Race, stability of health insurance coverage, and prescription medication use

OBJECTIVE

To determine the effects of health insurance and race on prescription medication use and expense.

METHODS

An observational, non-experimental design was used. Multivariable regression analyses were conducted to evaluate the independent effects of health insurance status and race on prescription medication use and expense while controlling for sociodemographic, geographic, and health status characteristics. The sample consisted of 19,035 participants in the 1996 through 2003 Medical Expenditure Panel Survey.

FINDINGS

European Americans spent about $300 to $400 more and used three to four more prescriptions annually compared to other racial groups. Prescription medication expenses increased as time spent uninsured increased. Participants with part-year coverage filled four fewer prescriptions than those with full-year health insurance coverage. Participants with private coverage spent less on prescription medications compared to those with public and those with dual public and private coverage ($1,194 vs. $1,931 and $2,076, respectively; p < or = 0.001).

CONCLUSIONS

Significant racial and health insurance status disparities in prescription medication use and expenses exist after controlling for sociodemographic, geographic, and health status characteristics.

Physical activity and obesity in African Americans: the Jackson Heart Study

OBJECTIVES

To better understand how obesity and low levels of physical activity (PA) contribute to racial health disparities, we examined the association of PA domains (work, home life, and leisure) with indicators of socioeconomic status and markers of obesity in African Americans.

METHODS

These cross sectional analyses of interview and clinical measures from the baseline visit of the Jackson Heart Study of cardiovascular disease (CVD) in African Americans of the Jackson, Mississippi metropolitan statistical area included 3,174 women and 1,830 men aged 21-95 years. The main measures were active living, sport, work, home life, and total PA scores; participation in regular moderate or vigorous intensity leisure physical activity (MVLPA); demographics, body mass index (BMI), waist circumference (WC) and CVD risk factors.

RESULTS

The sample was 63% female, 81% high school or college graduates, with 51% aged 45-64 years, and mostly overweight (32%) or obese (53%). Women were less active than men in all domains except home life. Total PA was inversely associated with WC in women and men. The overweight (BMI 25-29.9) group was most active in all domains except work; active living and sport PA and prevalence of MVLPA then declined in a dose response association with increasing BMI. Work PA was associated with the lowest BMI but otherwise with indicators of less favorable socioeconomic status and health.

CONCLUSIONS

Observed differences in PA in African Americans by domain and association with obesity biomarkers suggest areas for future study and intervention to reduce health disparities.

Employment status, coronary heart disease, and stroke among women

PURPOSE

To investigate the association of employment status with coronary heart disease (CHD) and ischemic stroke among middle-aged women.

METHODS

Proportional hazards regression was used to assess the association of employment status, incident CHD, and incident ischemic stroke among 7,058 women, ages 45-64 years at baseline (1987-1989), from the Atherosclerosis Risk in Communities Study.

RESULTS

After adjusting for age and race-field center, women employed outside the home had a decreased risk of CHD (hazard ratio [HR], 0.70; 95% confidence interval [95% CI], 0.56-0.86) and ischemic stroke (HR, 0.62; 95% CI, 0.47-0.84) compared with homemakers. Differences in cardiovascular disease risk factors partially accounted for the association of employment status and CHD (HR, 0.79; 95% CI, 0.63-0.99) and stroke (HR, 0.79; 95% CI, 0.58-1.08). Also, modest differences were noted when the results were stratified by education, with employed women having a lower risk of CHD (HR, 0.65; 95% CI, 0.45-0.93) than homemakers among those with less than a high school education.

CONCLUSIONS

Women employed outside of the home had a lower risk of CHD and stroke compared with homemakers and, for CHD, this association was stronger among women with less than a high school education. These findings suggest additional research into the varied occupational experiences of women, socioeconomic status, and health is warranted.

Dyslipidemia and the treatment of lipid disorders in African Americans

BACKGROUND

Despite the high prevalence of cardiovascular disease documented among the African-American population, there has been little emphasis on the role of dyslipidemia as a prominent risk factor in this large subpopulation. Questions of medication efficacy also have been raised. Together, these factors may have affected awareness, diagnosis, and treatment rates.

METHODS AND RESULTS

Dyslipidemia was defined as the presence of either hypercholesterolemia or hypertriglyceridemia using National Cholesterol Education Program III criteria and the fasting lipid measurements, self-reported treatment history, and medication survey available from 5302 Jackson Heart Study participants. Dyslipidemia was more common in men (compared with women) aged less than 50 years and increased with age in both genders. Hypercholesterolemia prevalence rates approached 50% in women aged more than 65 years. The lifestyle-related attributes found to be related to prevalence were being overweight and less physically active, and all disease status variables exhibited significant (P<.05) associations. Awareness of hypercholesterolemia is approximately 55% or more in both men and women aged more than 35 years. Treatment rates lag far behind awareness, particularly in younger adult men, and less than 50% of women and men aged less than 65 years were treated for hypercholesterolemia.

CONCLUSION

Higher rates of identification and effective treatment of dyslipidemia are clearly needed in this, and probably other African-American communities. Despite the less than optimal treatment, the identification and importance of the known cardiovascular disease states and risk factors in these analyses suggest the adoption of National Cholesterol Education Program III "high-risk strategy" algorithms in treatment recommendations and decisions by providers is occurring.

Social environmental stressors, psychological factors, and kidney disease

Kidney disease is one of the most striking examples of health disparities in American public health. Disparities in the prevalence and progression of kidney disease are generally thought to be a function of group differences in the prevalence of kidney disease risk factors such as diabetes, hypertension, and obesity. However, the presence of these comorbidities does not completely explain the elevated rate of progression from chronic kidney disease (CKD) to end-stage renal disease among high-risk populations such as African Americans. We believe that the social environment is an important element in the pathway from CKD risk factors to CKD and end-stage renal disease. This review of the literature draws heavily from social science and social epidemiology to present a conceptual frame specifying how social, economic, and psychosocial factors interact to affect the risks for and the progression of kidney disease.

Social environmental stressors, psychological factors, and kidney disease

Kidney disease is one of the most striking examples of health disparities in American public health. Disparities in the prevalence and progression of kidney disease are generally thought to be a function of group differences in the prevalence of kidney disease risk factors such as diabetes, hypertension, and obesity. However, the presence of these comorbidities does not completely explain the elevated rate of progression from chronic kidney disease (CKD) to end-stage renal disease among high-risk populations such as African Americans. We believe that the social environment is an important element in the pathway from CKD risk factors to CKD and end-stage renal disease. This review of the literature draws heavily from social science and social epidemiology to present a conceptual frame specifying how social, economic, and psychosocial factors interact to affect the risks for and the progression of kidney disease.

Prevalence and awareness of CKD among African Americans: the Jackson Heart Study

BACKGROUND

Chronic kidney disease (CKD) leads to end-stage renal disease and is a growing epidemic throughout the world. In the United States, African Americans have an incidence of end-stage renal disease 4 times that of whites.

STUDY DESIGN

Cross-sectional to examine the prevalence and awareness of CKD in African Americans.

SETTING & PARTICIPANTS

Observational cohort in the Jackson Heart Study (JHS).

PREDICTOR

CKD was defined as an estimated glomerular filtration rate less than 60 mL/min/1.73 m(2), the presence of albuminuria, or dialysis therapy.

OUTCOMES & MEASUREMENTS

Data from the JHS were analyzed. Medical history, including disease awareness and drug therapy, anthropometric measurements, and serum and urine samples, were obtained from JHS participants at the baseline visit. Associations between CKD prevalence and awareness and selected demographic, socioeconomic, health care access, and disease status parameters were assessed by using logistic regression models.

RESULTS

The prevalence of CKD in the JHS was 20%; CKD awareness was only 15.8%. Older participants had a greater prevalence, but also were more aware of CKD. Hypertension, diabetes, cardiovascular disease, hypercholesterolemia, hypertriglyceridemia, increasing age and waist circumference, and being single or less physically active were associated with CKD. Only advancing CKD stage was associated with awareness.

LIMITATIONS

Cross-sectional assessment, single urine measurement.

CONCLUSIONS

The JHS has a high prevalence and low awareness of CKD, especially in those with less severe disease status. This emphasizes the need for earlier diagnosis and increased education of health care providers and the general population.

Development and psychometric testing of a multidimensional instrument of perceived discrimination among African Americans in the Jackson Heart Study

OBJECTIVE

Assessing the discrimination-health disparities hypothesis requires psychometrically sound, multidimensional measures of discrimination. Among the available discrimination measures, few are multidimensional and none have adequate psychometric testing in a large, African American sample. We report the development and psychometric testing of the multidimensional Jackson Heart Study Discrimination (JHSDIS) Instrument.

METHODS

A multidimensional measure assessing the occurrence, frequency, attribution, and coping responses to perceived everyday and lifetime discrimination; lifetime burden of discrimination; and effect of skin color was developed and tested in the 5302-member cohort of the Jackson Heart Study. Internal consistency was calculated by using Cronbach alpha coefficient. Confirmatory factor analysis established the dimensions, and intercorrelation coefficients assessed the discriminant validity of the instrument.

SETTING

Tri-county area of the Jackson, MS metropolitan statistical area.

RESULTS

The JHSDIS was psychometrically sound (overall alpha = .78, .84 and .77, respectively, for the everyday and lifetime subscales). Confirmatory factor analysis yielded 11 factors, which confirmed the a priori dimensions represented.

CONCLUSIONS

The JHSDIS combined three scales into a single multidimensional instrument with good psychometric properties in a large sample of African Americans. This analysis lays the foundation for using this instrument in research that will examine the association between perceived discrimination and CVD among African Americans.

Prevalence, awareness, treatment, and control of hypertension in the Jackson Heart Study

African Americans have higher reported hypertension prevalence and lower control rates than other ethnic groups in the United States. Hypertension prevalence, awareness, treatment, and control (outcomes) and potentially associated demographic, lifestyle, comorbidity, and health care access factors were examined in 5249 adult participants (3362 women and 1887 men) aged 21 to 94 years enrolled in the Jackson Heart Study. Hypertension prevalence (62.9%), awareness (87.3%), treatment (83.2%), and control (66.4%) were high. Control declined with advancing age; estimates for all of the outcomes were higher for women compared with men. Lower socioeconomic status was associated with prevalence and control. Smoking was negatively associated with awareness and treatment, particularly among men. Comorbidities (diabetes, chronic kidney disease, and cardiovascular disease), likely driven by the high rates of obesity, correlated with hypertension prevalence, awareness, treatment, and control. Lack of health insurance was marginally associated with poorer control, whereas use of preventive care was positively associated with prevalence, awareness, and treatment, particularly among men. In comparisons with the 1994-2004 National Health and Nutrition Examination Survey data adjusted to Jackson Heart Study sex, age, and socioeconomic status distribution, control rates among Jackson Heart Study participants appeared to be higher than in their national counterparts and similar to that of whites. These results suggest that public health efforts to increase awareness and treatment among African Americans have been relatively effective. The Jackson Heart Study data indicate that better control rates can be achieved in this high-risk population.

Cumulative socioeconomic status across the life course and subclinical atherosclerosis

PURPOSE

The purpose of this study is to investigate the relationship between individual-level and neighborhood-level socioeconomic status (SES) across the life course and subclinical atherosclerosis.

METHODS

Participants from the Atherosclerosis Risk in Communities Study (n=12,332) were queried about individual-level SES and residential addresses across the life course. Individual-level measures were scored and summed to obtain a summary score (I-CumSES), whereas residential addresses were geocoded and linked to census data to obtain a summary neighborhood z score (N-CumSES) to evaluate the association of SES with intima-media thickness (IMT) and peripheral arterial disease (PAD).

RESULTS

A 1-SD lower I-CumSES was associated with greater mean IMT in each race-sex group and greater odds of PAD in white men (odds ratio [OR], 1.28; 95% confidence interval [CI], 0.99-1.64), white women (OR, 1.18; 95% CI, 1.02-1.36), and black women (OR, 1.33; 95% CI, 1.00-1.76). Compared with the highest tertile of N-CumSES, the lowest tertile was associated with greater mean IMT among whites, but was not associated with PAD for whites or blacks. When I-CumSES and N-CumSES were considered simultaneously, associations remained for only I-CumSES and were attenuated after adjustment for cardiovascular disease (CVD) risk factors.

CONCLUSIONS

Lower cumulative individual-level SES across the life course was associated with a greater burden of subclinical atherosclerosis, and this association was mediated in part by CVD risk factors.

Overweight and obesity: prevalence, consequences, and causes of a growing public health problem

This paper provides an overview of the evidence on the current epidemic of obesity in the United States. The prevalence of overweight and obesity now exceeds 60% among US adults, and the rate is rapidly increasing among children and adolescents. Dismal medical, social, and economic consequences are already apparent and likely to worsen without multipronged intervention. Increased rates of hypertension, diabetes, and dyslipidemia, among other medical conditions, threaten to shorten the longevity of the American populace by as much as 5 years. The incidence of depression is increasing and experts suggest this is linked with the increased prevalence of obesity. The cost of obesity-related medical care has increased astronomically since 1987, in addition to lost productivity and income. Novel multidisciplinary, preventive, and therapeutic approaches, and social changes are needed that address the complex interplay of biologic, genetic, and social factors that have created the current obesity epidemic.

Blood pressure usually considered normal is associated with an elevated risk of cardiovascular disease

PURPOSE

Research on the risk of cardiovascular disease among individuals with prehypertension (blood pressure 120/80 to 139/89 mm Hg) is incomplete. Additional information among individuals with a high risk of cardiovascular disease complications may help to focus current and future efforts.

SUBJECTS AND METHODS

We performed a prospective cohort analysis among 8960 middle-aged adults in the Atherosclerosis Risk in Communities (ARIC) study. The exposure variables were blood pressure levels: high normal blood pressure, systolic blood pressure 130-139 mm Hg or diastolic blood pressure 85-89 mm Hg; and normal blood pressure, systolic blood pressure 120-129 mm Hg or diastolic blood pressure 80-84 mm Hg. The outcome was incident cardiovascular disease defined as fatal/nonfatal coronary heart disease, cardiac procedure, silent myocardial infarction, or ischemic stroke. Subgroup analysis was performed among blacks, diabetics, individuals aged 55-64 years, individuals with renal insufficiency, and among individuals with varying levels of low-density lipoprotein (LDL) cholesterol and body mass index (BMI).

RESULTS

Compared with optimal blood pressure (systolic blood pressure <120 mm Hg and diastolic blood pressure <80 mm Hg), the relative risk (RR) of cardiovascular disease for high normal blood pressure was 2.33 (95% confidence interval [CI], 1.85-2.92), and RR for normal blood pressure was 1.81 (1.47-2.22); among blacks: RR for high normal blood pressure was 3.29 (95% CI, 1.68-6.45); among diabetics: RR for high normal blood pressure 4.10 (95% CI, 2.26-7.46); age 55-64 years: RR for high normal blood pressure 2.41 (95% CI, 1.75-3.30) among individuals with renal insufficiency: RR for high normal blood pressure was 1.90 (95% CI, 1.34-2.70); among individuals with BMI >30 kg/m2: RR for high normal blood pressure was 3.56 (95% CI, 1.99-6.35); and among individuals with LDL >160 mg/dL, RR for high normal blood pressure was 1.85 (95% CI, 1.26-2.72).

CONCLUSIONS

Individuals with prehypertensive levels of blood pressure have an increased risk of developing cardiovascular disease relative to those with optimal levels. The association is pronounced among blacks, among individuals with diabetes mellitus, and among those with high BMI.

Psychometric examination of the Daily Spiritual experiences Scale

Despite the burgeoning research literature addressing spirituality and its measurements, few instruments have undergone rigorous reliability and validity testing. This study contributed to determining the reliability and validity of the 16- and 6-item Daily Spiritual Experiences Scale (DSES) in a convenience sample of African Americans ages 34-85. Data were collected via self-administered questionnaire including the DSES and sociodemographic variables thought to influence spiritual experiences. Data were analyzed using paired t-tests, ANOVA, inter-class correlation coefficients, Pearson's correlation, and Cronbach's alpha. Both versions were stable over time, internally consistent, and the forms were equivalent and valid in an all-African American sample.

Dietary assessment in African Americans: methods used in the Jackson Heart Study

OBJECTIVES

The dietary assessment methods used in the Jackson Heart Study (JHS) with the entire cohort and a subset of the cohort who participated in a diet and physical activity substudy (DPASS) are reported. These methods were employed to validate culturally explicit data collection instruments developed by Delta Nutrition Intervention Research Initiative (NIRI) for assessing dietary intake in an all African-American cohort.

DESIGN

A validation/calibration design was employed. A short food frequency questionnaire (FFQ) was used with all JHS participants (N=5302). A long FFQ and four 24-hour diet recalls were used for the subset of DPASS participants (n=449).

OUTCOME MEASURES

Completion rates and preliminary macronutrient intakes are reported for the cohort and DPASS methods.

RESULTS

Participants (5302) in the JHS full cohort completed the short FFQ. Of these, 572 were enrolled in the DPASS. A total of 506 participants completed four 24-hour dietary recalls, and 499 completed all six measures, including the long FFQ. Validation of dietary instruments in African Americans will help assure that valid conclusions can be drawn regarding the effects of diet on cardiovascular disease in this population.

Sociocultural methods in the Jackson Heart Study: conceptual and descriptive overview

The Jackson Heart Study (JHS) is a prospective, population-based cohort study designed to investigate risk factors for cardiovascular disease (CVD) in African-American men and women. An aim of the JHS is the elucidation of the role that sociocultural factors play in the excess CVD risk and mortality in African Americans. Considerable evidence is available to document the influence of social, cultural, psychological, and other lifestyle risk factors on cardiovascular outcomes. Far less is known about how these factors affect health outcomes for African Americans. The JHS provides a unique opportunity to evaluate the presence and impact of these factors in this ethnoracial group. This paper describes the rationale and overall approach for sociocultural assessment in the JHS, both generally and for each content area.

Cardiovascular disease event classification in the Jackson Heart Study: methods and procedures

OBJECTIVE

The process of identifying, abstracting, and classifying cardiovascular disease (CVD) endpoints in the Jackson Heart Study (JHS) is described.

METHOD

Trained interviewers conduct telephone annual followup interviews on or near the JHS exam 1 anniversary to ascertain any significant health events since the last JHS contact, including diagnostic tests, hospitalizations, or death. Information on cohort hospitalizations and deaths is transmitted to the medical record abstraction (MRA) unit who review death certificates and hospital records to identify CVD events in the cohort. Interviews with the next of kin and completed questionnaires by physicians and medical examiners or coroners are used to obtain information on deaths in the cohort. A computer-generated diagnosis with follow-up review and adjudication by trained medical personnel completes final, disease-specific event classification of hospitalized and fatal coronary heart disease (CHD), stroke, and congestive heart failure (CHF) events.

DISCUSSION

Surveillance of this well-characterized group of African Americans for CVD events as well as sub- and preclinical manifestations of disease is a central aspect of the JHS. Particular focus is placed on the leading causes of CVD illness and death, including fatal and nonfatal CHD, stroke, and CHF.

Toward resolution of cardiovascular health disparities in African Americans: design and methods of the Jackson Heart Study

OBJECTIVE

The design, overall methods, and major phenotypes for the all-African-American Jackson Heart Study (JHS) are detailed.

METHODS

Participants were enrolled from the three counties that make up the Jackson, Mississippi metropolitan area. Relatives of selected participants were recruited to develop a large, nested family cohort. Participants provided extensive medical and social history, had an array of physical and biochemical measurements and diagnostic procedures, and provided genomic DNA.

RESULTS

Data and biologic materials have been collected from 5302 adult African Americans, including 1499 members of 291 families. Participants have a high prevalence of diabetes, hypertension, obesity, and related disorders.

DISCUSSION

The JHS dataset and biologic materials (serum, DNA, and cryopreserved cells) offer a valuable resource for the study of diseases that are of particular importance to African Americans.

Physical activity assessment methods in the Jackson Heart Study

OBJECTIVES

Physical activity measures used in exam 1 of the Jackson Heart Study (JHS), including the diet and physical activity substudy (DPASS), are described.

DESIGN

The JHS physical activity (PAC) survey instrument was administered by interview. Accelerometer data, pedometer step counts, and additional questionnaire data were collected from volunteer subsamples of the cohort, including the DPASS.

OUTCOME MEASURES

The PAC assessed four different domains of physical activity (active living, work, home and garden, and sport and exercise indexes). The 24-hour accelerometer and pedometer monitoring provided objective measures for validation of cohort survey responses. The DPASS past week activity (PWA) questionnaire assessed time spent in moderate and vigorous activity during the previous seven days. Pedometer step counts for three days before three DPASS visits provided additional data for the DPASS.

RESULTS

5296 respondents completed the PAC, 423 completed 24-hour accelerometer monitoring, and 499 completed the DPASS measures; 85 completed both 24-hour monitoring and DPASS measures. Initial analyses of leisure and sports activity items showed similar distributions for men and women and for the cohort and DPASS participants, in a bimodal distribution, with similar proportions reporting infrequent and frequent activity. The physical activity measures from the JHS can provide unique information about the association between physical activity, other risk factors, and cardiovascular disease in African Americans.

Study design for genetic analysis in the Jackson Heart Study

OBJECTIVE

This paper describes the preparation of genetic materials and the recruitment and initial characterization of a nested Family Study within the Jackson Heart Study (JHS) METHODS: Genomic DNA was prepared from all consenting JHS participants. In addition, family members of a subset of JHS participants were recruited to the JHS Family Study to allow heritability and linkage analyses and family-based association studies. Family Study participants completed the same questionnaires, measures, and procedures as all other JHS participants and provided blood samples for lymphocyte cryopreservation and transformation.

RESULTS

DNA samples were obtained from 4726 JHS participants, including 1499 members of 291 families. In the family cohort, estimated heritabilities of body mass index, selected lipid levels, and blood pressure are highly significant, supporting the validity of the sample.

DISCUSSION

The JHS data and genetic materials (DNA and cryopreserved cells) offer valuable opportunities to identify susceptibility alleles for common complex diseases by positional and candidate gene approaches.

Recruiting African-American research participation in the Jackson Heart Study: methods, response rates, and sample description

OBJECTIVE

The sampling and recruitment methods, response rate, and cohort description for the all-African-American Jackson Heart Study (JHS) are detailed.

METHODS

Four subsamples of participants residing in the Jackson, Mississippi metropolitan statistical area (MSA) were included: random, volunteer, ARIC (continuing from Atherosclerosis Risk in Communities study), and family. A community-driven recruitment model was developed, and community representatives guided recruitment.

RESULTS

96% (n=5,302) of target enrollment was achieved with diversity in sex, education, and income. The JHS cohort provides a sample of African-American adults for longitudinal investigation.

DISCUSSION

Cohort recruitment was challenging. The JHS experiences provide useful lessons for observational epidemiological studies recruiting African-American research participation. Co-participation of researchers and researched in study design and realistic evidence of community benefit were crucial to recruitment success.

Women's Employment Status and Mortality: The Atherosclerosis Risk in Communities Study

BACKGROUND

As women's labor force participation in the United States has increased over the past decades, there has been an interest in the potential health effects of employment. To date, however, research findings have been contradictory.

METHODS

Thus, the aim of this study was to investigate the association between employment status and mortality among 7361 middle-aged African American and white women who participated in the Atherosclerosis Risk in Communities (ARIC) Study. Women were classified as employed or homemakers at the baseline examination (1987-1989) and were followed for approximately 11 years. Proportional hazards regression was used to estimate unadjusted and adjusted hazard ratios.

RESULTS

After adjusting for sociodemographic factors and selected risk factors for mortality, employed women had a lower risk of mortality than homemakers (hazard ratio [HR] = 0.65, 95% confidence interval [CI] = 0.49, 0.86). This decreased risk of mortality persisted in additional analyses that excluded those who died within the first 2 years of follow-up or, alternatively, those with a history of coronary heart disease (CHD), stroke, cancer, hypertension, diabetes, or a perception of fair or poor health at baseline. In cause of death-specific analyses, the mortality advantage among employed women persisted for circulatory system-related deaths; however, the association for cancer-related deaths was weaker, and the CI included one.

CONCLUSIONS

As the association between employment status and mortality was not explained by known risk factors for mortality, additional research is needed to identify other potential factors that may help to explain this relationship.