Carotid Intima-Media Thickness and Improved Stroke Risk Assessment in Hypertensive Black Adults

BACKGROUND

We aim to determine the added value of carotid intima-media thickness (cIMT) in stroke risk assessment for hypertensive Black adults.

METHODS

We examined 1,647 participants with hypertension without a history of cardiovascular (CV) disease, from the Jackson Heart Study. Cox regression analysis estimated hazard ratios (HRs) for incident stroke per standard deviation increase in cIMT and quartiles while adjusting for baseline variables. We then evaluated the predictive capacity of cIMT when added to the pool cohort equations (PCEs).

RESULTS

The mean age at baseline was 57 ± 10 years. Each standard deviation increase in cIMT (0.17 mm) was associated with approximately 30% higher risk of stroke (HR 1.27, 95% confidence interval: 1.08-1.49). Notably, cIMT proved valuable in identifying residual stroke risk among participants with well-controlled blood pressure, showing up to a 56% increase in the odds of stroke for each 0.17 mm increase in cIMT among those with systolic blood pressure <120 mm Hg. Additionally, the addition of cIMT to the PCE resulted in the reclassification of 58% of low to borderline risk participants with stroke to a higher-risk category and 28% without stroke to a lower-risk category, leading to a significant net reclassification improvement of 0.22 (0.10-0.30).

CONCLUSIONS

In this community-based cohort of middle-aged Black adults with hypertension and no history of CV disease at baseline, cIMT is significantly associated with incident stroke and enhances stroke risk stratification.

Examining the Relationship Between Multilevel Resilience Resources and Cardiovascular Disease Incidence, Overall and by Psychosocial Risks, Among Participants in the Jackson Heart Study, the Multi-Ethnic Study of Atherosclerosis, and the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study

We examined relationships between resilience resources (optimism, social support, and neighborhood social cohesion) and cardiovascular disease (CVD) incidence and assessed potential effect-measure modification by psychosocial risk factors (e.g., stress, depression) among adults without CVD in 3 cohort studies (2000-2018): the Jackson Heart Study, the Multi-Ethnic Study of Atherosclerosis, and the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study. We fitted adjusted Cox models accounting for within-neighborhood clustering while censoring at dropout or non-CVD death. We assessed for effect-measure modification by psychosocial risks. In secondary analyses, we estimated standardized risk ratios using inverse-probability-weighted Aalen-Johansen estimators to account for confounding, dropout, and competing risks (non-CVD deaths) and obtained 95% confidence intervals (CIs) using cluster bootstrapping. For high and medium (versus low) optimism (n = 6,243), adjusted hazard ratios (HRs) for incident CVD were 0.94 (95% CI: 0.78, 1.13) and 0.90 (95% CI: 0.75, 1.07), respectively. Corresponding HRs were 0.88 (95% CI: 0.74, 1.04) and 0.92 (95% CI: 0.79, 1.06) for social support (n = 7,729) and 1.10 (95% CI: 0.94, 1.29) and 0.99 (95% CI: 0.85, 1.16) for social cohesion (n = 7,557), respectively. Some psychosocial risks modified CVD HRs. Secondary analyses yielded similar findings. For optimism and social support, an inverse relationship was frequently most compatible with the data, but a positive relationship was also compatible. For neighborhood social cohesion, positive and null relationships were most compatible. Thus, specific resilience resources may be potential intervention targets, especially among certain subgroups.

Association Between Social Determinants of Health and Glycemic Control Among African American People with Type 2 diabetes: The Jackson Heart Study

BACKGROUND

Social determinants of health have a significant impact on health outcomes. However, the complexity and interaction of multiple factors influencing glycemic control remain understudied.

PURPOSE

This study examined associations of socioeconomic position (income, education, and occupation), environmental (physical activity facilities, neighborhood social cohesion, neighborhood problem, and violence), behavioral (physical activity, nutrition, and smoking), and psychological factors (depressive symptoms, stress, and discrimination) with glycemic control (hemoglobin A1c [A1c]) using the World Health Organization Social Determinants of Health framework in African American adults with type 2 diabetes.

METHODS

A secondary data analysis was conducted using a longitudinal cohort of 1,240 African American adults with type 2 diabetes who participated in the community-based Jackson Heart Study. Socioeconomic position, environmental, behavioral, and psychological factors were measured using validated instruments in the Jackson Heart Study. Longitudinal structural equation modeling was used with glycemic control (A1c) collected over time (Exams 1-3) as the study outcome.

RESULTS

Our study presents the complex interplay of socioeconomic determinants of health and glycemic control over time. Higher socioeconomic position (higher income, higher level of education, and professional occupation) was directly associated with improvement in glycemic control over time. An association of socioeconomic position on glycemic control mediated through health behavior factors was also observed.

CONCLUSIONS

In this analysis, socioeconomic position components were determinants of glycemic control in African American adults with type 2 diabetes. Future studies aimed at reducing health disparities and achieving equality of outcomes in this population will benefit from embedding socioeconomic position components into their design.

Identification of a SGCD × Discrimination Interaction Effect on Systolic Blood Pressure in African American Adults in the Jackson Heart Study

BACKGROUND

In the United States, hypertension disproportionately afflicts over half of African American adults, many of whom also experience racial discrimination. Understanding gene × discrimination effects may help explain racial disparities in hypertension.

METHODS

We tested for the main effects and interactive effects of 5 candidate single nucleotide polymorphisms (SNPs: rs2116737, rs11190458, rs2445762, rs2597955, and rs2416545) and experiences of discrimination on blood pressure (BP) in African Americans not taking antihypertensive medications in the Jackson Heart Study from Mississippi (n = 2,933). Multiple linear regression models assumed an additive genetic model and adjusted for ancestry, age, sex, body mass index, education, and relatedness. We additionally tested recessive and dominant genetic models.

RESULTS

Discrimination was significantly associated with higher diastolic BP (P = 0.003). In contrast, there were no main effects of any SNP on BP. When analyzing SNPs and discrimination together, SGCD (Sarcoglycan Delta; rs2116737) demonstrated a gene × environment interaction. Specifically, an SGCD × Discrimination interaction was associated with systolic BP (β =1.95, P = 0.00028) in a recessive model. Participants carrying a T allele, regardless of discrimination experiences, and participants with a GG genotype and high experiences of discrimination had higher systolic BP than participants with a GG genotype and low experiences of discrimination. This finding suggests the SGCD GG genotype may have a protective effect on systolic BP, but only in a setting of low discrimination.

CONCLUSIONS

The inclusion of culturally relevant stressors, like discrimination, may be important to understand the gene-environment interplay likely underlying complex diseases with racial health inequities.

Impact of Asleep and 24-Hour Blood Pressure Data on the Prevalence of Masked Hypertension by Race/Ethnicity

BACKGROUND

We pooled ambulatory blood pressure monitoring data from 5 US studies, including the Jackson Heart Study (JHS), the Coronary Artery Risk Development in Young Adults (CARDIA) study, the Masked Hypertension Study, the Improving the Detection of Hypertension Study, and the North Carolina Masked Hypertension Study. Using a cross-sectional study design, we estimated differences in the prevalence of masked hypertension by race/ethnicity when out-of-office blood pressure (BP) included awake, asleep, and 24-hour BP vs. awake BP alone.

METHODS

We restricted the analyses to participants with office systolic BP (SBP) <130 mm Hg and diastolic BP (DBP) <80 mm Hg. High awake BP was defined as mean SBP/DBP ≥130/80 mm Hg, high asleep BP as mean SBP/DBP ≥110/65 mm Hg, and high 24-hour BP as mean SBP/DBP ≥125/75 mm Hg.

RESULTS

Among participants not taking antihypertensive medication (n = 1,292), the prevalence of masked hypertension with out-of-office BP defined by awake BP alone or by awake, asleep, or 24-hour BP was 34.5% and 48.7%, respectively, among non-Hispanic White, 39.7% and 67.6% among non-Hispanic Black, and 19.4% and 35.1% among Hispanic participants. After multivariable adjustment, non-Hispanic Black were more likely than non-Hispanic White participants to have masked hypertension by asleep or 24-hour BP but not awake BP (adjusted odds ratio [OR] 2.14 95% confidence interval [CI] 1.45-3.15) and by asleep or 24-hour BP and awake BP (OR 1.61; 95% CI 1.12-2.32) vs. not having masked hypertension.

CONCLUSIONS

Assessing asleep and 24-hour BP measures increases the prevalence of masked hypertension more among non-Hispanic Black vs. non-Hispanic White individuals.

Predicting Out-of-Office Blood Pressure in a Diverse US Population

BACKGROUND

The PRedicting Out-of-OFfice Blood Pressure (PROOF-BP) algorithm accurately predicted out-of-office blood pressure (BP) among adults with suspected high BP in the United Kingdom and Canada. We tested the accuracy of PROOF-BP in a diverse US population and evaluated a newly developed US-specific algorithm (PROOF-BP-US).

METHODS

Adults with ≥2 office BP readings and ≥10 awake BP readings on 24-hour ambulatory BP monitoring from 4 pooled US studies were included. We compared mean awake BP with predicted out-of-office BP using PROOF-BP and PROOF-BP-US. Our primary outcomes were hypertensive out-of-office systolic BP (SBP) ≥130 mm Hg and diastolic BP (DBP) ≥80 mm Hg.

RESULTS

We included 3,058 adults, mean (SD) age was 52.0 (11.9) years, 38% were male, and 54% were Black. The area under the receiver-operator characteristic (AUROC) curve (95% confidence interval) for hypertensive out-of-office SBP was 0.81 (0.79-0.82) and DBP was 0.76 (0.74-0.78) for PROOF-BP. For PROOF-BP-US, the AUROC curve for hypertensive out-of-office SBP was 0.82 (0.81-0.83) and for DBP was 0.81 (0.79-0.83). The optimal predicted out-of-office BP ranges for out-of-office BP measurement referral were 120-134/75-84 mm Hg for PROOF-BP and 125-134/75-84 mm Hg for PROOF-BP-US. The 2017 American College of Cardiology/American Heart Association BP guideline (referral range 130-159/80-99 mm Hg) would refer 93.1% of adults not taking antihypertensive medications with office BP ≥130/80 mm Hg in the National Health and Nutrition Examination Survey for out-of-office BP measurement, compared with 53.1% using PROOF-BP and 46.8% using PROOF-BP-US.

CONCLUSIONS

PROOF-BP and PROOF-BP-US accurately predicted out-of-office hypertension in a diverse sample of US adults.

Lung function impairment and risk of incident heart failure: the NHLBI Pooled Cohorts Study

AIMS

The aim is to evaluate associations of lung function impairment with risk of incident heart failure (HF).

METHODS AND RESULTS

Data were pooled across eight US population-based cohorts that enrolled participants from 1987 to 2004. Participants with self-reported baseline cardiovascular disease were excluded. Spirometry was used to define obstructive [forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) <0.70] or restrictive (FEV1/FVC ≥0.70, FVC <80%) lung physiology. The incident HF was defined as hospitalization or death caused by HF. In a sub-set, HF events were sub-classified as HF with reduced ejection fraction (HFrEF; EF <50%) or preserved EF (HFpEF; EF ≥50%). The Fine-Gray proportional sub-distribution hazards models were adjusted for sociodemographic factors, smoking, and cardiovascular risk factors. In models of incident HF sub-types, HFrEF, HFpEF, and non-HF mortality were treated as competing risks. Among 31 677 adults, there were 3344 incident HF events over a median follow-up of 21.0 years. Of 2066 classifiable HF events, 1030 were classified as HFrEF and 1036 as HFpEF. Obstructive [adjusted hazard ratio (HR) 1.17, 95% confidence interval (CI) 1.07-1.27] and restrictive physiology (adjusted HR 1.43, 95% CI 1.27-1.62) were associated with incident HF. Obstructive and restrictive ventilatory defects were associated with HFpEF but not HFrEF. The magnitude of the association between restrictive physiology and HFpEF was similar to associations with hypertension, diabetes, and smoking.

CONCLUSION

Lung function impairment was associated with increased risk of incident HF, and particularly incident HFpEF, independent of and to a similar extent as major known cardiovascular risk factors.

Electrocardiogram machine learning for detection of cardiovascular disease in African Americans: the Jackson Heart Study

AIMS

Almost half of African American (AA) men and women have cardiovascular disease (CVD). Detection of prevalent CVD in community settings would facilitate secondary prevention of CVD. We sought to develop a tool for automated CVD detection.

METHODS AND RESULTS

Participants from the Jackson Heart Study (JHS) with analysable electrocardiograms (ECGs) (n=3679; age, 6212 years; 36% men) were included. Vectorcardiographic (VCG) metrics QRS, T, and spatial ventricular gradient vectors magnitude and direction, and traditional ECG metrics were measured on 12-lead ECG. Random forests, convolutional neural network (CNN), lasso, adaptive lasso, plugin lasso, elastic net, ridge, and logistic regression models were developed in 80% and validated in 20% samples. We compared models with demographic, clinical, and VCG input (43 predictors) and those after the addition of ECG metrics (695 predictors). Prevalent CVD was diagnosed in 411 out of 3679 participants (11.2%). Machine learning models detected CVD with the area under the receiver operator curve (ROC AUC) 0.690.74. There was no difference in CVD detection accuracy between models with VCG and VCG + ECG input. Models with VCG input were better calibrated than models with ECG input. Plugin-based lasso model consisting of only two predictors (age and peak QRS-T angle) detected CVD with AUC 0.687 [95% confidence interval (CI) 0.6250.749], which was similar (P=0.394) to the CNN (0.660; 95% CI 0.5970.722) and better (P<0.0001) than random forests (0.512; 95% CI 0.4930.530).

CONCLUSIONS

Simple model (age and QRS-T angle) can be used for prevalent CVD detection in limited-resources community settings, which opens an avenue for secondary prevention of CVD in underserved communities.

Using Predicted Atherosclerotic Cardiovascular Disease Risk for Discrimination of Awake or Nocturnal Hypertension

BACKGROUND

Several atherosclerotic cardiovascular disease (ASCVD) risk factors are associated with awake and nocturnal hypertension.

METHODS

We assessed the association between a composite ASCVD risk score and awake or nocturnal hypertension using data from participants aged 40-79 years who completed ambulatory blood pressure monitoring at the Year 30 Coronary Artery Risk Development in Young Adults study exam in 2015-2016 (n = 716) and the baseline Jackson Heart Study exam in 2000-2004 (n = 770). Ten-year predicted ASCVD risk was calculated using the Pooled Cohort risk equations. Awake hypertension was defined as mean awake systolic blood pressure (SBP) ≥135 mm Hg or diastolic blood pressure (DBP) ≥85 mm Hg and nocturnal hypertension was defined as mean asleep SBP ≥120 mm Hg or DBP ≥70 mm Hg.

RESULTS

Among participants with a 10-year predicted ASCVD risk <5%, 5% to <7.5%, 7.5% to <10%, and ≥10%, the prevalence of awake or nocturnal hypertension as a composite outcome was 29.5%, 47.8%, 62.2%, and 69.7%, respectively. After multivariable adjustment, higher ASCVD risk was associated with higher prevalence ratios for awake or nocturnal hypertension among participants with clinic-measured SBP/DBP <130/85 mm Hg but not ≥130/85 mm Hg. The C-statistic for discriminating between participants with vs. without awake or nocturnal hypertension was 0.012 (95% confidence interval 0.003, 0.016) higher when comparing a model with ASCVD risk and clinic-measured blood pressure (BP) together vs. clinic-measured BP without ASCVD risk.

CONCLUSIONS

Using 10-year predicted ASCVD risk in conjunction with clinic BP improves discrimination between individuals with and without awake or nocturnal hypertension.

Association of Obstructive Sleep Apnea With Nighttime Blood Pressure in African Americans: The Jackson Heart Study

BACKGROUND

Obstructive sleep apnea (OSA), nocturnal hypertension, and nondipping systolic blood pressure (BP) are each highly prevalent among African Americans. However, few data are available on the association between OSA and nighttime BP in this population.

METHODS

We examined the association of OSA with nighttime BP among African Americans who completed 24-hour ambulatory BP monitoring (ABPM) at Exam 1 (2000-2004) of the Jackson Heart Study (JHS) and subsequently participated in the JHS Sleep Study (2012-2016). Type 3 home sleep apnea testing was used to assess OSA measures, including respiratory event index (REI4%) and percent sleep time <90% oxygen saturation (nocturnal hypoxemia). Nocturnal hypertension was defined as mean asleep systolic BP (SBP) ≥120 mm Hg or diastolic BP (DBP) ≥70 mm Hg. Multivariable linear regression models were fit to estimate the association between each OSA measure and nighttime SBP and DBP.

RESULTS

Among 206 participants who completed ABPM and participated in the Jackson Heart Sleep Study, 50.5% had nocturnal hypertension and 26.2% had moderate to severe OSA (REI4% ≥15 events/hour). After multivariable adjustment, each SD (13.3 events/hour) increase in REI4% was associated with 1.75 mm Hg higher nighttime DBP (95% confidence interval (CI): 0.38, 3.11) and a prevalence ratio of 1.11 (95% CI: 1.00, 1.24) for nocturnal hypertension. Each SD (10.4%) increase in nocturnal hypoxemia was associated with a 1.91 mm Hg higher nighttime SBP (95% CI: 0.15, 3.66).

CONCLUSIONS

Severity of OSA and nocturnal hypoxemia were associated with high nighttime BP in African American participants in the JHS.

The Association of ARMC5 with the Renin-Angiotensin-Aldosterone System, Blood Pressure, and Glycemia in African Americans

CONTEXT

Armadillo repeat containing 5 (ARMC5) on chromosome 16 is an adrenal gland tumor suppressor gene associated with primary aldosteronism, especially among African Americans (AAs). We examined the association of ARMC5 variants with aldosterone, plasma renin activity (PRA), blood pressure, glucose, and glycosylated hemoglobin A1c (HbA1c) in community-dwelling AAs.

METHODS

The Jackson Heart Study is a prospective cardiovascular cohort study in AAs with baseline data collection from 2000 to 2004. Kernel machine method was used to perform a single joint test to analyze for an overall association between the phenotypes of interest (aldosterone, PRA, systolic and diastolic blood pressure [SBP, DBP], glucose, and HbA1c) and the ARMC5 single nucleotide variants (SNVs) adjusted for age, sex, BMI, and medications; followed by Baysian Lasso methodology to identify sets of SNVs in terms of associated haplotypes with specific phenotypes.

RESULTS

Among 3223 participants (62% female; mean age 55.6 (SD ± 12.8) years), the average SBP and DBP were 127 and 76 mmHg, respectively. The average fasting plasma glucose and HbA1c were 101 mg/dL and 6.0%, respectively. ARMC5 variants were associated with all 6 phenotypes. Haplotype TCGCC (ch16:31476015-31476093) was negatively associated, whereas haplotype CCCCTTGCG (ch16:31477195-31477460) was positively associated with SBP, DBP, and glucose. Haplotypes GGACG (ch16:31477790-31478013) and ACGCG (ch16:31477834-31478113) were negatively associated with aldosterone and positively associated with HbA1c and glucose, respectively. Haplotype GCGCGAGC (ch16:31471193-ch16:31473597(rs114871627) was positively associated with PRA and negatively associated with HbA1c.

CONCLUSIONS

ARMC5 variants are associated with aldosterone, PRA, blood pressure, fasting glucose, and HbA1c in community-dwelling AAs, suggesting that germline mutations in ARMC5 may underlie cardiometabolic disease in AAs.

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.