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Cardiovascular disease (CVD) morbidity and mortality are high among black adults. We aimed to study the granular subclinical relations of aortic stiffness and left ventricular (LV) function and remodeling in blacks, in whom limited data are available. In the Jackson Heart Study, 1050 U.S. community-dwelling black adults without CVD underwent 1.5 T cardiovascular magnetic resonance. We assessed regional and global aortic stiffness and LV structure and function, including LV mass indexed to body surface area (LVMI), end-diastolic volume (LVEDV), ejection fraction (EF), and global and regional circumferential strain (Ecc). Phase contrast images of the cross-sectional aorta at the pulmonary artery bifurcation and abdominal aorta bifurcation were acquired to measure pulse wave velocity of the aortic arch (AA-PWV) and thoracic aorta (T-PWV). Results of multivariable-adjusted analyses are presented as SD unit change in LV variables per SD change in PWV variables. Participants were 62% women with mean age of 59 ± 10 years. Higher AA-PWV and T-PWV were associated with greater LVMI: for T-PWV, β = 0.10, 95% CI = 0.03-0.16, p = 0.002. Higher AA-PWV and T-PWV were associated with worse (more positive) Ecc at the LV base (for AA-PWV, β = 0.13, 95% CI = 0.05-0.20, p = 0.0007), but not mid-LV or apex. AA-PWV and T-PWV were not associated with LV mass/LVEDV or EF. In this cross-sectional study of blacks without CVD in the U.S., aortic stiffness is associated with subclinical adverse LV function in basal segments. Future studies may elucidate the temporal relationships of aortic stiffness on the pattern and progression of LV remodeling, dysfunction, and associated prognosis in blacks., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Background Measures of vascular dysfunction are related to adverse cardiovascular disease (CVD) outcomes in non-Hispanic, White populations; however, data from Black individuals are limited. We aimed to investigate the associations between novel hemodynamic measures and prevalent CVD in a sample of Black individuals. Methods and Results Among older Black participants of the Jackson Heart Study, we assessed noninvasive vascular hemodynamic measures using arterial tonometry and Doppler ultrasound. We assessed 5 measures of aortic stiffness and wave reflection (carotid-femoral pulse wave velocity, pulse wave velocity ratio, forward pressure wave amplitude, central pulse pressure, and augmentation index), and 2 measures of microvascular function (baseline and hyperemic brachial flow velocity). Using multivariable logistic regression models, we examined the relations between vascular hemodynamic measures and prevalent CVD. In models adjusted for traditional CVD risk factors, higher carotid-femoral pulse wave velocity (odds ratio [OR],1.25; 95% CI, 1.01-1.55; P =0.04), lower augmentation index (OR, 0.84; 95% CI, 0.70-0.99; P =0.05), and lower hyperemic brachial flow velocity (OR, 0.77; 95% CI, 0.65-0.90; P =0.001) were associated with higher odds of CVD. After further adjustment for hypertension treatment, lower augmentation index (OR, 0.84; 95% CI, 0.70-0.99; P =0.04) and hyperemic brachial flow velocity (OR, 0.79; 95% CI, 0.67-0.94; P =0.006), but not carotid-femoral pulse wave velocity (OR, 1.23; 95% CI, 0.99-1.051; P =0.06), were associated with higher odds of CVD. Conclusions In a sample of older Black individuals, more severe microvascular damage and aortic stiffness were associated with prevalent CVD. Further research on hemodynamic mechanisms that contribute to cardiovascular risk among older Black individuals is merited.

Background Blacks have more severe endothelial dysfunction and aortic stiffening as compared with whites. We aimed to investigate the association between aortic stiffness and microvascular function in the black community. Methods and Results We assessed the association between forearm vascular reactive hyperemia (an indicator of microvascular function) and aortic stiffness in 1458 black participants (N=965 [66% women]; mean age: 66±11 years) in the Jackson Heart Study. We evaluated 2 measures of aortic stiffness: brachial pulse pressure and carotid-femoral pulse wave velocity. Using high-resolution ultrasound and Doppler, we evaluated brachial blood flow at baseline and during reactive hyperemia after 5 minutes of forearm ischemia. Multiple cardiovascular risk factors were significantly related to baseline and hyperemic brachial flow velocity. Women had lower baseline flow across the entire age spectrum. During hyperemia, we observed a significant age-sex interaction for flow velocity ( P=0.02). Female sex was protective against microvascular dysfunction among younger participants, but older women exhibited a greater attenuation of the hyperemic flow reserve. In multivariable models that adjusted for cardiovascular disease risk factors and mean arterial pressure, higher carotid-femoral pulse wave velocity (β=-0.106±0.033; P=0.001 was related to lower baseline flow. However, during reactive hyperemia, elevated brachial pulse pressure (β=-0.070±0.031; P=0.03) and carotid-femoral pulse wave velocity (β=-0.128±0.030; P<0.001) were both related to attenuated brachial flow velocity. Conclusions In a sample of blacks, higher aortic stiffness and pressure pulsatility were associated with lower flow reserve during reactive hyperemia, beyond changes attributable to traditional cardiovascular disease risk factors alone.

Importance: Cardiovascular risk assessment is a fundamental component of prevention of cardiovascular disease (CVD). However, commonly used prediction models have been formulated in primarily or exclusively white populations. Whether risk assessment in black adults is dissimilar to that in white adults is uncertain., Objectives: To develop and validate risk prediction models for CVD incidence in black adults, incorporating standard risk factors, biomarkers, and subclinical disease., Design, Setting, and Participants: The Jackson Heart Study (JHS), a longitudinal community-based study of 5301 black adults in Jackson, Mississippi. Inclusive study dates were the date of a participant's first visit (September 2000 to March 2004) to December 31, 2011. The median (75th percentile) follow-up was 9.1 (9.7) years. The dates of the analysis were August 2013 to May 2015. Measurements included standard risk factors, including age, sex, body mass index, systolic and diastolic blood pressure, ratio of fasting total cholesterol to high-density lipoprotein cholesterol, estimated glomerular filtration rate, antihypertensive therapy, diabetes mellitus, and smoking; blood biomarkers; and subclinical disease measures, including ankle-brachial index, carotid intimal-medial thickness, and echocardiographic left ventricular hypertrophy and systolic dysfunction., Main Outcomes and Measures: Incident CVD event was defined as the first occurrence of myocardial infarction, coronary heart disease death, congestive heart failure, stroke, incident angina, or intermittent claudication. Model performance was compared with the American College of Cardiology/American Heart Association (ACC/AHA) CVD risk algorithm and the Framingham Risk Score (FHS) refitted to the JHS data and evaluated in the Atherosclerosis Risk in Communities (ARIC) and Multi-Ethnic Study of Atherosclerosis cohorts., Results: The study cohort comprised 3689 participants with mean (SD) age at baseline was 53 (11) years, and 64.8% (n = 2390) were female. Over a median of 9.1 years, 270 participants (166 women) experienced a first CVD event. A simple combination of standard CVD risk factors, B-type natriuretic peptide, and ankle-brachial index (model 6) yielded modest improvement over a model without B-type natriuretic peptide and ankle-brachial index (C statistic, 0.79; 95% CI, 0.75-0.83 [relative integrated discrimination improvement, 0.22; 95% CI, 0.15-0.30]). However, the reclassification improvement was not substantially different between model 6 and the ACC/AHA CVD Pooled Cohort risk equations or between model 6 and the FHS. The models discriminated reasonably well in the ARIC and Multi-Ethnic Study of Atherosclerosis data (C statistic range, 0.70-0.77)., Conclusions and Relevance: Our findings using the JHS data in the present study are valuable because they confirm that current FHS and ACC/AHA risk algorithms work well in black individuals and are not easily improved on. A unique risk calculator for black adults may not be necessary., Competing Interests: Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Pencina reported receiving grants from Regeneron/Sanofi outside of the present work. Dr Butler reported receiving grant support from the National Heart, Lung, and Blood Institute–Atherosclerosis Risk in Communities study and the Jackson Heart Study during the conduct of the study. Dr Herrington reported receiving grants from the National Institutes of Health during the conduct of the study. Dr Taylor reported receiving grants from the National Institutes of Health, during the conduct of the study, and reported receiving personal fees from Alnylam Pharmaceuticals outside of the present work. No other disclosures were reported.

Background: Numerous experimental studies suggest that B-type natriuretic peptide (BNP) is cardioprotective; however, in clinical studies, higher plasma BNP concentrations have been associated with incident cardiovascular disease and higher left ventricular mass. Genetic association studies may allow us to determine the true causal directions without confounding by compensatory mechanisms., Methods and Results: We performed a meta-analysis of 2 genome-wide association results from a total of 2790 blacks. We assumed an additive genetic model in an association analysis of imputed 2.5 million single-nucleotide polymorphism dosages with residuals generated from multivariable-adjusted logarithmically transformed BNP controlling for relevant covariates and population stratification. Two loci were genome-wide significant, a candidate gene locus NPPB (rs198389, P=1.18×10(-09)) and a novel missense variant in the KLKB1 locus (rs3733402, P=1.75×10(-11)) that explained 0.4% and 1.9% of variation in log BNP concentration, respectively. The observed increase in BNP concentration was proportional to the number of effect allele copies, and an average of 8.1 pg/mL increase was associated with 2 allele copies. In a companion study, single-nucleotide polymorphisms in this loci were cross-checked with genome-wide association results for the aldosterone/renin ratio in individuals of European ancestry, and rs3733402 was genome-wide significant (P<5.0×10(-8)), suggesting possible shared genetic architecture for these 2 pathways. Other statistically significant relations for these single-nucleotide polymorphisms included the following: rs198389 with systolic blood pressure in blacks (COGENT consortium) and rs198389 and rs3733402 with left ventricular mass in whites (EchoGEN consortium)., Conclusions: These findings improve our knowledge of the genetic basis of BNP variation in blacks, demonstrate a possible shared allelic architecture for BNP with aldosterone-renin ratio, and motivate further studies of underlying mechanisms., (© 2015 American Heart Association, Inc.)