Modifiers of Plasma 25-Hydroxyvitamin D and Chronic Kidney Disease Outcomes in Black Americans: The Jackson Heart Study

BACKGROUND

25-hydroxyvitamin D [25(OH)D] is lower in black compared with white Americans but is not consistently associated with outcomes in this group, possibly due to genetic and other biological differences. We examined the association of plasma 25(OH)D and renal outcomes in black Americans with a focus on effect modifiers.

METHODS

We studied associations between baseline 25(OH)D with (i) annual rate of estimated glomerular filtration rate (eGFR) decline and (ii) incident chronic kidney disease (CKD) in the Jackson Heart Study, a prospective cohort of black Americans. Plasma 25(OH)D levels were corrected for monthly variation in sunlight exposure using the residual method. We used adjusted generalized linear models to evaluate outcomes and assessed potential effect modification by diabetes mellitus, vitamin D binding protein (DBP) genotype, obesity, dietary sodium intake, and use of renin-angiotensin-aldosterone system inhibitors.

RESULTS

Among 5164 participants with 25(OH)D available, plasma 25(OH)D was 14.5 ± 6.5 ng/mL (mean ± SD), and eGFR was 94.1 ± 22.0 mL/min/1.73 m2. Over a median of 8 years, eGFR decline was 1.3 ± 2.0 mL/min/1.73 m2 per year in 3228 participants with complete data, and 220 out of 1803 eligible participants developed incident CKD. Overall, 25(OH)D was not associated with eGFR decline in fully adjusted models. However, higher 25(OH)D was associated with slower eGFR decline among those with diabetes: each 5 ng/mL higher 25(OH)D was associated with a 0.27 mL/min/1.73 m2/y slower eGFR decline (95% CI, 0.13 to 0.41; P < 0.001). Higher 25(OH)D was not associated with incident CKD overall, but it was associated with lower odds of incident CKD among participants with the GG or GT genotype at rs7041 in the gene encoding DBP [OR, 0.69 per 5 ng/mL higher 25(OH)D; 95% CI, 0.51 to 0.93; P-interaction = 0.005]. Other interactions were not significant.

CONCLUSION

These findings support a potential benefit of higher 25(OH)D for kidney health in black Americans with diabetes or specific variants in DBP.

Identification of Resilient and At-Risk Neighborhoods for Cardiovascular Disease Among Black Residents: the Morehouse-Emory Cardiovascular (MECA) Center for Health Equity Study

INTRODUCTION

Despite the growing interest in place as a determinant of health, areas that promote rather than reduce cardiovascular disease (CVD) in blacks are understudied. We performed an ecologic analysis to identify areas with high levels of CVD resilience and risk among blacks from a large southern, US metropolitan area.

METHODS

We obtained census tract-level rates of cardiovascular deaths, emergency department (ED) visits, and hospitalizations for black adults aged 35 to 64 from 2010 through 2014 for the Atlanta, Georgia, metropolitan area. Census tracts with substantially lower rates of cardiovascular events on the basis of neighborhood socioeconomic status were identified as resilient and those with higher rates were identified as at risk. Logistic regression was used to estimate the odds ratios (OR) and 95% confidence intervals (CIs) of being classified as an at-risk versus resilient tract for differences in census-derived measures.

RESULTS

We identified 106 resilient and 121 at-risk census tracts, which differed in the rates per 5,000 person years of cardiovascular outcomes (mortality, 8.13 vs 13.81; ED visits, 32.25 vs 146.3; hospitalizations, 26.69 vs 130.0), despite similarities in their median black income ($46,123 vs $45,306). Tracts with a higher percentage of residents aged 65 or older (odds ratio [OR], 2.29; 95% CI, 1.41-3.85 per 5% increment) and those with incomes less than 200% of the federal poverty level (OR, 1.19; 95% CI, 1.02-1.39 per 5% increment) and greater Gini index (OR, 1.56; 95% CI, 1.19- 2.07 per 0.05 increment) were more likely to be classified as at risk than resilient neighborhoods.

DISCUSSION

Despite matching on median income level, at-risk neighborhoods for CVD among black populations were associated with a higher prevalence of socioeconomic indicators of inequality than resilient neighborhoods.

The association of morning serum cortisol with glucose metabolism and diabetes: The Jackson Heart Study

BACKGROUND

Serum cortisol levels have been associated with type 2 diabetes (T2D). However, the role of cortisol in glycemia and T2D is not fully elucidated among African Americans (AAs). We hypothesized that among AAs morning serum cortisol would be positively associated with glycemic measures and prevalent T2D.

METHODS

We examined the cross-sectional association of baseline morning serum cortisol with fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), homeostasis model assessment of insulin resistance (HOMA-IR), β-cell function (HOMA-β), and prevalent T2D in the Jackson Heart Study. Linear regression models were used to examine the association of log-transformed cortisol with glycemic traits, stratified by T2D status. Logistic regression was used to examine the association of log-transformed cortisol with prevalent T2D. Models were adjusted for age, sex, education, occupation, systolic blood pressure, waist circumference, physical activity, smoking, beta-blocker/hormone replacement medications and cortisol collection time.

RESULTS

Among 4,206 AAs (mean age 55 ± 13 years, 64% female), 19% had prevalent T2D. A 100% increase in cortisol among participants without diabetes was associated with 2.7 mg/dL (95% CI: 2.0, 3.3) higher FPG and a 10.0% (95% CI: -14.0, -6.0) lower HOMA-β with no significant association with HbA1c or HOMA-IR. In participants with diabetes, a 100% increase in cortisol was associated with a 23.6 mg/dL (95% CI: 13.6, 33.7) higher FPG and a 0.6% (95% CI: 0.3, 0.9) higher HbA1c. Among all participants, quartile 4 vs. 1 of cortisol was associated with a 1.26-fold (95% CI: 1.75, 2.91) higher odds of prevalent T2D.

CONCLUSION

Higher morning serum cortisol was associated with higher FPG and lower β-cell function among participants without T2D and higher FPG and HbA1c in participants with diabetes. Among all participants, higher cortisol was associated with higher odds of T2D. These findings support a role for morning serum cortisol in glucose metabolism among AAs.

SAT-LB017 Anthropometric Imaging and Biological Markers of Adiposity and Aldosterone among African Americans: The Jackson Heart Study

Serum aldosterone increases risk of cardiometabolic disease. Pre-clinical studies suggest adipocytes produce aldosterone, independent of adrenal synthesis. Human studies have linked obesity and aldosterone, but mixed results exist between body fat distribution and aldosterone (1, 2). Body fat distribution varies by race with African Americans (AAs) having more subcutaneous adipose tissue (SAT) than visceral adipose tissue (VAT) compared to whites adjusted for total body fat (3). Thus, we examined the association of anthropometric, imaging and biological markers of adiposity with aldosterone among AAs. We used data from Exams 1 (2000-2004) and 2 (2005-2008) of the Jackson Heart Study, a large prospective study of AA adults. Descriptive statistics were obtained for demographic and clinical characteristics including mean and standard deviation (SD) for the continuous variables and frequencies for the categorical variables. Aldosterone, adiponectin, and leptin were log-transformed due to skewed distribution. Multivariable linear regression models were used to assess the associations of adiposity markers at Exam 1 (body mass index [(BMI]), waist circumference [(WC)], waist-to-height ratio [(WHR)], leptin, adiponectin) and at Exam 2 (VAT, SAT and liver attenuation [liver fat]) with aldosterone levels assessed at Exam 1. Models were adjusted for age, sex, education, occupation, systolic blood pressure, smoking and physical activity. Among 4994 adults (mean age 55.1 years ± 12.8, 63% female), the average BMI was 31.8 ± 7.3 kg/m². After full adjustment, a 1 unit increase in WC (cm) and BMI (kg/m²) were associated with a 0.5% and 0.8% higher aldosterone, respectively (both p<0.01). A 1% increase in adiponectin was associated with a 0.15% lower aldosterone (p<0.01); whereas, a 1% increase in leptin was associated with a 0.15% higher aldosterone (p<0.01). Compared to the highest BMI category (≥30 kg/m²), the 25-30 and <25 categories showed a 7.2% and 19% lower aldosterone, respectively (both p<0.01). A 1% increase in VAT was associated with a 0.18% increase in aldosterone and a 1% increase in liver attenuation was associated with a 0.34% decrease in aldosterone (both p<0.01), but no significant association was found with SAT. In conclusion, anthropometric measures of obesity, VAT and leptin were positively associated with serum aldosterone, while adiponectin and liver attenuation were negatively associated with serum aldosterone. These data suggest that adiposity may play a role in aldosterone levels among AAs. 1. O’Seaghdha et al, BMC Endocr Disord 12: 3, 2012; 2. Harada et al, Clin. Endocrinol. (Oxf.) 79, 510-516 (2013); 3. Katzmarzyk, et al. Am. J. Clin. Nutr. 91, 7-15 (2010). Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Association of psychosocial factors with leukocyte telomere length among African Americans in the Jackson Heart Study

Leukocyte telomere length (LTL) is a biomarker of cellular aging. African Americans report more stress than other groups; however, the association of psychosocial stressors with biological aging among African Americans remains unclear. The current study evaluated the association of psychosocial factors (negative affect and stressors) with LTL in a large sample of African American men and women (n = 2,516) from the Jackson Heart Study. Using multivariable linear regression, we examined the sex-specific associations of psychosocial factors (cynical distrust, anger in and out, depressive symptoms, negative affect summary scores, global stress, weekly stress, major life events, and stress summary scores) with LTL. Model 1 adjusted for demographics and education. Model 2 adjusted for model 1, smoking, alcohol intake, physical activity, diabetes, hypertension, and high-sensitivity C-reactive protein. Among women, high (vs. low) cynical distrust was associated with shorter mean LTL in model 1 (b = -0.12; p = 0.039). Additionally, high (vs. low) anger out and expressed negative affect summary scores were associated with shorter LTL among women after full adjustment (b = -0.13; p = 0.011; b = -0.12, p = 0.031, respectively). High levels of cynical distrust, anger out, and negative affect summary scores may be risk factors for shorter LTL, particularly among African-American women.

Multi-ancestry genome-wide gene-smoking interaction study of 387,272 individuals identifies new loci associated with serum lipids

The concentrations of high- and low-density-lipoprotein cholesterol and triglycerides are influenced by smoking, but it is unknown whether genetic associations with lipids may be modified by smoking. We conducted a multi-ancestry genome-wide gene-smoking interaction study in 133,805 individuals with follow-up in an additional 253,467 individuals. Combined meta-analyses identified 13 new loci associated with lipids, some of which were detected only because association differed by smoking status. Additionally, we demonstrate the importance of including diverse populations, particularly in studies of interactions with lifestyle factors, where genomic and lifestyle differences by ancestry may contribute to novel findings.

Evaluation of Allostatic Load as a Mediator of Sleep and Kidney Outcomes in Black Americans

Introduction

Poor sleep associates with adverse chronic kidney disease (CKD) outcomes yet the biological mechanisms underlying this relation remain unclear. One proposed mechanism is via allostatic load, a cumulative biologic measure of stress.

Methods

Using data from 5177 Jackson Heart Study participants with sleep measures available, we examined the association of self-reported sleep duration: very short, short, recommended, and long (≤5, 6, 7–8, or ≥9 hours per 24 hours, respectively) and sleep quality (high, moderate, low) with prevalent baseline CKD, and estimated glomerular filtration rate (eGFR) decline and incident CKD at follow-up. CKD was defined as eGFR <60 ml/min per 1.73 m² or urine albumin-to-creatinine ratio ≥30 mg/g. Models were adjusted for demographics, comorbidities, and kidney function. We further evaluated allostatic load (quantified at baseline using 11 biomarkers from neuroendocrine, metabolic, autonomic, and immune domains) as a mediator of these relations using a process analysis approach.

Results

Participants with very short sleep duration (vs. 7–8 hours) had greater odds of prevalent CKD (odds ratio [OR] 1.31, 95% confidence interval [CI] 1.03–1.66). Very short, short, or long sleep duration (vs. 7–8 hours) was not associated with kidney outcomes over a median follow-up of 8 years. Low sleep quality (vs. high) associated with greater odds of prevalent CKD (OR 1.26, 95% CI 1.00–1.60) and 0.18 ml/min per 1.73 m² (95% CI 0.00–0.36) faster eGFR decline per year. Allostatic load did not mediate the associations of sleep duration or sleep quality with kidney outcomes.

Conclusions

Very short sleep duration and low sleep quality were associated with adverse kidney outcomes in this all-black cohort, but allostatic load did not appear to mediate these associations.

Influence of individual life course and neighbourhood socioeconomic position on dietary intake in African Americans: the Jackson Heart Study

OBJECTIVE

African Americans, especially those in the Southeastern USA, have different dietary behaviours from the general US population, and have the highest prevalence, incidence and mortality of diet-related disease outcomes, such as cardiovascular disease. However, there are scant data regarding factors such as socioeconomic position (SEP) across the life course that influence dietary behaviours in this high-risk population. Our aim was to examine the impact of life course and neighbourhood SEPs on dietary intake among African Americans.

PARTICIPANTS AND SETTING

Data for this cross-sectional analysis came from the community-based Jackson Heart Study (JHS). We analysed a total of 3948 JHS participants (mean age: 55.4±12.5; 63.9% women), who had complete dietary intake and covariate information.

METHODS

We examined the associations of childhood SEP (CSEP), adulthood SEP (ASEP) and neighbourhood SEP (NSEP) with 10 selected dietary intake measures, using multilevel log-gamma generalised linear regression models.

OUTCOME MEASURES

Dietary intake measures include daily saturated fat, sodium, protein, fibre, fruits and vegetables, whole grains, sugar-sweetened beverage, nuts, fish and processed meat.

RESULTS

In age, sex and total energy intake adjusted models, most dietary intakes were associated with these three SEP measures. After additional adjustment for other SEP measures, most of the significant associations with CSEP and NSEP were attenuated, except for the associations of fibre with CSEP (relative rate [RR] [95% CI] 1.05 [1.00-1.10]) and whole grains with NSEP (RR [95% CI] 1.28 [1.02-1.61]). The associations (shown as RR [95% CI]) between ASEP and sugar-sweetened beverage: 0.70 (0.59-0.83), processed meat: 0.75 (0.63-0.90), sodium: 0.99 (0.94-1.00), fibre: 1.10 (1.03-1.16), protein: 1.05 (1.01-1.09), fruits and vegetables: 1.21 (1.11-1.32), nuts: 2.13 (1.59-2.87), and fish: 1.57 (1.27-1.95) generally persisted after additional adjustment for both CSEP and NSEP. However, the association between ASEP and whole grains was attenuated.

CONCLUSIONS

High ASEP may have a more beneficial influence on dietary practices in African Americans than CSEP or NSEP.

Financial Stress and Risk of Coronary Heart Disease in the Jackson Heart Study

INTRODUCTION

Financial hardship is associated with coronary heart disease risk factors, and may disproportionately affect some African American groups. This study examines whether stress because of financial hardship is associated with incident coronary heart disease in African Americans.

METHODS

The Jackson Heart Study is a longitudinal cohort study of cardiovascular disease risks in African Americans in the Jackson, Mississippi metropolitan statistical area. Participant enrollment began in 2000. Analyses were performed in 2017 and included adjudicated endpoints through December 2012. Financial stress was assessed from the Jackson Heart Study Weekly Stress Inventory and categorized into four levels: (1) did not experience financial stress, (2) no stress, (3) mild stress, and (4) moderate to high stress. Incident coronary heart disease was defined as the first event of definite or probable myocardial infarction, definite fatal myocardial infarction, definite fatal coronary heart disease, or cardiac procedure. There were 2,256 individuals in this analysis.

RESULTS

Participants with moderate to high (versus no) financial stress were more likely to have incident coronary heart disease events after controlling for demographics, SES, access to care, and traditional clinical risk factors (hazard ratio=2.42, 95% CI=1.13, 5.17). The association between financial stress and coronary heart disease was no longer statistically significant in a model adjusting for three specific risk factors: depression, smoking status, and diabetes (hazard ratio=1.99, 95% CI=0.91, 4.39).

CONCLUSIONS

Financial stress may be an unrecognized risk factor for coronary heart disease for African Americans. Additional research should examine these associations in intervention studies that address perceived stress, in addition to other coronary heart disease risk factors, in patients experiencing financial stress.

Sex differences in the association of psychosocial resources with prevalent type 2 diabetes among African Americans: The Jackson Heart Study

AIM

To examine the association of psychosocial resources with prevalent type 2 diabetes (T2D) in 5104 African American men and women.

METHODS

Using data from the Jackson Heart Study (JHS), we evaluated the cross-sectional associations of four psychosocial resources (social support, optimism, religiosity, and social networks) with T2D [fasting glucose ≥126 mg/dL, or HbA1c ≥ 6.5%, or use of diabetic medication]. Multivariable Poisson regression estimated prevalence ratios (PR, 95% confidence interval-CI) of T2D by each psychosocial measure, adjusting for demographics, SES, waist circumference, health behaviors, and depressive symptoms.

RESULTS

Women reported greater religiosity and had more social networks than men (p < 0.001). High (vs. low) social support was associated with a lower prevalence of T2D among men after full adjustment (PR 0.74, 95% CI 0.59-0.91). Women with high (vs. low) social networks had a 16% lower prevalence of T2D (PR 0.84, 95% CI 0.73-0.96) after full adjustment. High (vs. low) optimism was associated with a 20% lower prevalence of T2D after adjustment for age (PR 0.80, 95% CI 0.65-0.98). Religiosity was not associated with T2D.

CONCLUSION

Social support and networks should be considered in efforts to prevent T2D among a high-risk group such as African Americans.

Low use of routine medical care among African Americans with high CKD risk: the Jackson Heart Study

Background

Use of routine medical care (RMC) is advocated to address ethnic/racial disparities in chronic kidney disease (CKD) risks, but use is less frequent among African Americans. Factors associated with low RMC use among African Americans at risk of renal outcomes have not been well studied.

Methods

We examined sociodemographic, comorbidity, healthcare access, and psychosocial (discrimination, anger, stress, trust) factors associated with low RMC use in a cross-sectional study. Low RMC use was defined as lack of a physical exam within one year among participants with CKD (estimated glomerular filtration rate < 60 mL/min/1.73m² or urine albumin-to-creatinine ratio > 30 mg/g) or CKD risk factors (diabetes or hypertension). We used multivariable logistic regression to estimate the odds of low RMC use at baseline (2000–2004) for several risk factors.

Results

Among 3191 participants with CKD, diabetes, or hypertension, 2024 (63.4%) were ≥ 55 years of age, and 700 (21.9%) reported low RMC use. After multivariable adjustment, age < 55 years (OR 1.61 95% CI 1.31–1.98), male sex (OR 1.71; 1.41–2.07), <high school diploma (OR 1.31; 1.07–1.62), absence of hypertension (OR 1.74; 1.27–2.39) or diabetes (OR 1.34; 1.09–1.65), and tobacco use (OR 1.43; 1.18–1.72) were associated with low RMC use. Low trust in providers (OR 2.16; 1.42–3.27), high stress (OR 1.41; 1.09–1.82), high daily discrimination (OR 1.30; 1.01–1.67) and low burden of lifetime discrimination (OR 1.52; 1.18–1.94), were also associated with low RMC use.

Conclusions

High-risk African Americans who were younger, male, less-educated, and with low trust in providers were more likely to report low RMC use. Efforts to improve RMC use by targeting these populations could mitigate African Americans’ disparities in CKD risks.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1190-0) contains supplementary material, which is available to authorized users.

The social patterning of electronic nicotine delivery system use among US adults

There is little research examining the social patterning of electronic nicotine delivery system (ENDS) use. This study investigated the association between socioeconomic status (SES) (education, income, and employment status) and current and former ENDS use. Data were collected from 2561 participants from the American Heart Association Tobacco Regulatory and Addiction Center (A-TRAC) online survey. Participants were 18-64 years old and reported demographic, SES, and ENDS use. Poisson regression was used to estimate prevalence ratios (PR 95% confidence interval-CI) of participants' current and former (vs. never) ENDS use. Models were adjusted for age, sex, sexual orientation, race/ethnicity, marital status, and reasons for ENDS use. In the unadjusted analysis, ENDS use was primarily patterned by education and employment status. College educated persons (vs. those with less than a high school diploma) had a 37% greater prevalence of current ENDS use (PR 1.37, 95% CI 1.20-1.55), and a 16% greater prevalence of former ENDS use (PR 1.16, 95% CI 1.06-1.28) in the fully-adjusted model. Persons with household incomes above $90 K (vs. less than $20,000) had a greater prevalence of current (PR 1.30, 95% CI 1.19-1.41) and former (PR 1.17, 95% CI 1.05-1.30) ENDS use. Those who were employed (vs. not employed) had a 13% greater prevalence of current ENDS use (PR 1.13, 95% CI 1.07-1.19) after full adjustment. Higher SES (vs. lower SES) persons were more likely to use ENDS.

The Epidemiology of Coping in African American Adults in the Jackson Heart Study (JHS)

Differences in coping within the African American population are not well understood, yet these differences may be critical to reducing stress, improving health, and reducing racial health disparities. Using a descriptive, exploratory analysis of the Jackson Heart Study (N = 5301), we examine correlations between coping responses and associations between coping and demographic, socioeconomic, psychosocial, and neighborhood factors. Overall, coping responses were not strongly correlated and patterns of associations between covariates and coping responses were largely inconsistent. The results suggest that coping varies substantially within this African American population and is driven mainly by psychosocial factors such as spirituality and interpersonal support. Understanding these complex relationships may inform strategies by which to intervene in the stress process to mitigate the effects of stress on health and to identify vulnerable subgroups of African Americans that might need targeted interventions to reduce exposure to stressors and improve coping capacities.

Relation of multi-marker panel to incident chronic kidney disease and rapid kidney function decline in African Americans: the Jackson Heart Study

Background

Few investigations have evaluated the incremental usefulness of multiple biomarkers representing varying physiological pathways for predicting risk of renal outcomes in African Americans.

Design, setting, participants, and measurements

We related a multi-marker panel to incident chronic kidney disease (CKD) and rapid kidney function decline (RKFD) in 2813 Jackson Heart Study participants without prevalent CKD at exam 1 (2000–2004) and with complete assays at exam 1 for 9 biomarkers: adiponectin, aldosterone, B-natriuretic peptide [BNP], cortisol, high sensitivity C-reactive protein (hsCRP), endothelin, homocysteine, plasma renin activity and mass. Incident CKD was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m² at exam 3 while RKFD was defined as eGFR ≥30% loss between exams 1 and 3 (8.2 median years). We employed multiple logistic regression model to describe association between the panel and incident CKD and RKFD and used backward elimination strategy to estimate the most parsimonious biomarker model while controlling for conventional risk factors.

Results

The multi-marker panel predicted the risk for both incident CKD (odds ratios [OR], 2.72; 95% confidence intervals [CI], 1.63, 4.56; P = 0.001) and RKFD (2.61; 95% CI, 1.67, 4.08; P < 0.001). Per standard deviation increase in log biomarker concentrations were significantly (multivariable adjusted odds ratios, [95% confidence interval], p-value) associated with incident CKD: plasma adiponectin (1.24 [1.07, 1.44], p = 0.005) and leptin (1.3 [1.06, 1.61], p = 0.011), and with RKFD: plasma adiponectin (1.22 [1.06, 1.40], p = 0.006); hsCRP (1.17 [1.01, 1.36], p = 0.031) and aldosterone (0.85 [0.74, 0.96], p = 0.012). Moderate levels (3rd quartile) of aldosterone were inversely associated with incident CKD (0.54 [0.35, 0.82], p = 0.004) while leptin was associated with RKFD (1.64 [1.10, 2.44], p = 0.015). Biomarkers improved CKD risk prediction (P = 0.003) but not RKFD risk prediction (P = 0.10).

Conclusion

In this community-based sample of African Americans, a multi-marker panel added only moderate predictive improvement compared to conventional risk factors.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1026-y) contains supplementary material, which is available to authorized users.

Abstract P170: Morning Surge and Cardiovascular Events in African Americans: The Jackson Heart Study

Introduction: A larger sleep-trough morning surge, defined as the mean two-hour post-awakening blood pressure (BP) minus the lowest asleep BP, has been associated with cardiovascular disease (CVD) events in Asians and Europeans. High asleep BP in African Americans (AA) may preclude a morning surge and an association with CVD due to a smaller BP change upon awakening.

Objective: Determine the association of morning surge with CVD events in AAs.

Methods: We analyzed participants from the Jackson Heart Study, a community-based cohort of AAs, with a complete 24-hour ambulatory BP monitoring recording and self-report asleep and awake times at baseline in 2000-2004 (n=767). Participants were grouped into tertiles of sleep-trough morning surge, two-hour post-awakening BP and lowest sleep BP. CVD events (nonfatal/fatal stroke, nonfatal myocardial infarction or fatal coronary heart disease; n=61) through December 2012 were adjudicated.

Results: Participants’ mean age was 59.2 years and 32.1% were male. Multivariable adjusted hazard ratios (95% CI) for CVD events associated with Tertile 2 and 3 versus Tertile 1 of morning systolic BP (SBP) surge were 1.45 (0.71 – 2.97) and 2.03 (0.98 – 4.23), respectively; of post-awakening SBP were 2.01 (0.81 – 4.99) and 4.41 (1.85 – 10.50), respectively; and of lowest asleep SBP were 1.55 (0.68 – 3.52) and 2.22 (0.96 – 5.14), respectively ( Table ). Also, there was a graded increasing risk for CVD associated with Tertile 2 and 3 versus Tertile 1 of post-awakening diastolic BP (DBP), but not morning DBP surge and lowest asleep DBP.

Conclusion: Higher morning SBP surge, post-awakening SBP and lowest asleep SBP and DBP were associated increased CVD risk in AAs.

Correction to: Goal-Striving Stress is Associated with Chronic Kidney Disease Among Participants in the Jackson Heart Study

Please note the following correction in the Methods section of this article: The definition for goal-striving stress in the Jackson Heart Study included achievement defined as "where one was in life 10 years ago," using a 10-point scale.

Masked hypertension and kidney function decline: the Jackson Heart Study

BACKGROUND

Hypertension diagnosed by blood pressure (BP) measured in the clinic is associated with rapid kidney function decline (RKFD) and incident chronic kidney disease (CKD). The extent to which hypertension defined using out-of-clinic BP measurements is associated with these outcomes is unclear.

METHODS

We evaluated the association of any masked hypertension (daytime SBP/DBP ≥ 135/85 mmHg, night-time SBP/DBP ≥ 120/70 mmHg or 24-h SBP/DBP ≥ 130/80 mmHg) with RKFD and incident CKD among 676 African-Americans in the Jackson Heart Study with clinic-measured SBP/DBP less than 140/90 mmHg who completed ambulatory BP monitoring in 2000-2004. RKFD was defined as a decline in estimated glomerular filtration rate (eGFR) at least 30% and incident CKD was defined as development of eGFR less than 60 ml/min per 1.73 m with an at least 25% decline in eGFR between 2000-2004 and 2009-2013.

RESULTS

The mean age of participants was 57.6 years, 28.8% were men and 52.7% had any masked hypertension. After a median follow-up of 8 years, 13.8 and 8.6% of participants had RKFD and incident CKD, respectively. In unadjusted analyses, masked hypertension was associated with an increased odds for incident CKD [odds ratio (OR) 2.20, 95% confidence interval (CI) 1.22, 3.97]. This association remained statistically significant after adjustment for demographic characteristics, baseline eGFR and albumin-to-creatinine ratio (OR 1.95, 95% CI 1.04, 3.67) but was eliminated after propensity score adjustment (OR 1.62, 95% CI 0.87, 3.00). There was no association between masked hypertension and RKFD.

CONCLUSION

Masked hypertension may be associated with the development of CKD in African-Americans.

Novel genetic associations for blood pressure identified via gene-alcohol interaction in up to 570K individuals across multiple ancestries

Heavy alcohol consumption is an established risk factor for hypertension; the mechanism by which alcohol consumption impact blood pressure (BP) regulation remains unknown. We hypothesized that a genome-wide association study accounting for gene-alcohol consumption interaction for BP might identify additional BP loci and contribute to the understanding of alcohol-related BP regulation. We conducted a large two-stage investigation incorporating joint testing of main genetic effects and single nucleotide variant (SNV)-alcohol consumption interactions. In Stage 1, genome-wide discovery meta-analyses in ≈131K individuals across several ancestry groups yielded 3,514 SNVs (245 loci) with suggestive evidence of association (P < 1.0 x 10-5). In Stage 2, these SNVs were tested for independent external replication in ≈440K individuals across multiple ancestries. We identified and replicated (at Bonferroni correction threshold) five novel BP loci (380 SNVs in 21 genes) and 49 previously reported BP loci (2,159 SNVs in 109 genes) in European ancestry, and in multi-ancestry meta-analyses (P < 5.0 x 10-8). For African ancestry samples, we detected 18 potentially novel BP loci (P < 5.0 x 10-8) in Stage 1 that warrant further replication. Additionally, correlated meta-analysis identified eight novel BP loci (11 genes). Several genes in these loci (e.g., PINX1, GATA4, BLK, FTO and GABBR2) have been previously reported to be associated with alcohol consumption. These findings provide insights into the role of alcohol consumption in the genetic architecture of hypertension.

Stress and Achievement of Cardiovascular Health Metrics: The American Heart Association Life's Simple 7 in Blacks of the Jackson Heart Study

Background

Ideal cardiovascular health metrics (defined by the American Heart Association Life's Simple 7 [LS7]) are suboptimal among blacks, which results in high risk of cardiovascular disease. We examined the association of multiple stressors with LS7 components among blacks.

Methods and Results

Using a community‐based cohort of blacks (N=4383), we examined associations of chronic stress, minor stressors, major life events, and a cumulative stress score with LS7 components (smoking, diet, physical activity, body mass index, blood pressure, total cholesterol, and fasting plasma glucose) and an LS7 composite score. Multivariable logistic regression assessed the odds of achieving intermediate/ideal levels of cardiovascular health adjusted for demographic, socioeconomic, behavioral, and biomedical factors. The LS7 components with the lowest percentages of intermediate/ideal cardiovascular health levels were diet (39%), body mass index (47%), and physical activity (51%). Higher chronic, minor, and cumulative stress scores were associated with decreased odds (odds ratio [OR]) of achieving intermediate/ideal levels for smoking (OR [95% confidence interval], 0.80 [0.73–0.88], 0.84 [0.75–0.94], and 0.81 [0.74–0.90], respectively). Participants with more major life events had decreased odds of achieving intermediate/ideal levels for smoking (OR, 0.84; 95% confidence interval, 0.76–0.92) and fasting plasma glucose (OR, 0.90; 95% confidence interval, 0.82–0.98). Those with higher scores for minor stressors and major life events were less likely to achieve intermediate or ideal LS7 composite scores (OR [95% confidence interval], 0.89 [0.81–0.97] and 0.91 [0.84–0.98], respectively).

Conclusions

Blacks with higher levels of multiple stress measures are less likely to achieve intermediate or ideal levels of overall cardiovascular health (LS7 composite score), specific behaviors (smoking), and biological factors (fasting plasma glucose).

Use of BMI as the marker of adiposity in a metabolic syndrome severity score: Derivation and validation in predicting long-term disease outcomes

BACKGROUND

Estimates of adiposity in evaluating the metabolic syndrome (MetS) have traditionally utilized measures of waist circumference (WC), whereas body mass index (BMI) is more commonly used clinically. Our objective was to determine if a MetS severity Z-score employing BMI as its measure of adiposity (MetS-Z-BMI) would perform similarly to a WC-based score (MetS-Z-WC) in predicting future disease.

METHODS

To formulate the MetS-Z-BMI, we performed confirmatory factor analysis on a sex- and race/ethnicity-specific basis on MetS-related data for 6870 adult participants of the National Health and Nutrition Survey 1999-2010. We then validated this score and compared it to MetS-Z-WC in assessing correlations with future coronary heart disease (CHD) and Type 2 diabetes mellitus (T2DM) using Cox proportional hazard analysis of 13,094 participants of the Atherosclerosis Risk in Communities study and Jackson Heart Study.

RESULTS

Loading factors, which represent the relative contribution of each component to the latent MetS factor, were lower for BMI than for WC in formulating the two respective scores (MetS-Z-BMI and MetS-Z-WC). Nevertheless, MetS-Z-BMI and MetS-Z-WC exhibited similar hazard ratios (HR) toward future disease. For each one standard-deviation-unit increase in MetS-Z-BMI, HR for CHD was 1.76 (95% confidence interval [CI]: 1.65, 1.88) and HR for T2DM was 3.39 (CI 3.16, 3.63) (both p < 0.0001). There were no meaningful differences between the MetS-Z-WC and MetS-Z-BMI scores in their associations with future CHD and T2DM.

CONCLUSIONS

A MetS severity Z-score utilizing BMI as its measure of adiposity operated similarly to a WC-based score in predicting future CHD and T2DM, suggesting overall similarity in MetS-based risk as estimated by both measures of adiposity. This indicates potential clinical usefulness of MetS-Z-BMI in assessing and following MetS-related risk over time.

Intentional and unintentional medication non-adherence in African Americans: Insights from the Jackson Heart Study

BACKGROUND

Non-adherence to medications is common and leads to suboptimal outcomes. Non-adherence can be intentional (e.g., deciding to skip dosages) or unintentional (e.g., forgetting), yet few studies have distinguished these reasons. An improved understanding of the reasons for non-adherence could inform the development of effective interventions.

METHODS AND RESULTS

We analyzed data from African Americans in the Jackson Heart Study who were prescribed medications for one or more chronic conditions. Participants were grouped by patient-reported adherence with non-adherence categorized as being intentional, unintentional or both. We used modified Poisson regression models to examine the factors associated with types of non-adherence. Of 2933 participants taking medication, 2138 (72.9%) reported non-adherence with 754 (35.3%) reporting only unintentional non-adherence, 263 (12.3%) only intentional non-adherence, and 1121 (52.4%) both. Factors independently associated with intentional non-adherence included female sex and depressive symptoms while factors associated with unintentional non-adherence included younger age and separated relationship status. Unintentional and intentional non-adherence was more common among participants taking anti-arrhythmic and anti-asthmatic medications, respectively. Higher levels of global perceived stress was associated with both types of non-adherence. The adjusted models for intentional and unintentional non-adherence had c-statistics of 0.65 and 0.66, respectively, indicating modest discrimination.

CONCLUSION

Specific patient factors and individual medication classes were associated with distinct patterns of intentional and unintentional non-adherence, yet the overall modest discrimination of the models suggests contributions from other unmeasured factors. These findings provide a construct for understanding reasons for non-adherence and provide rationale to assess whether personalized interventions can improve adherence.