Background and Purpose The association between left atrial (LA) size, ischemic stroke, and death has not been well established in African Americans despite their disproportionately higher rates of stroke and cardiovascular mortality compared to non-Hispanic whites. Methods For the analysis, participants in the Jackson cohort of the Atherosclerosis Risk in Communities Study were followed from the date of the echocardiogram in cycle three to the date of the first ischemic stroke event (or death) or to December 31, 2004 if no ischemic stroke event (or death) was detected. Results There were 1886 participants in the study population (mean age 58.9 years, 65% women). Participants in the top quintile of LA diameter indexed to height (LA diameter/height; 2.57 to 3.55 cm/m) were more likely women, hypertensive, diabetic, and obese compared to those not in the top quintile. Over a median follow-up of 9.8 years for ischemic stroke and 9.9 years for all-cause mortality, there were 106 strokes and 242 deaths. In a multivariable model adjusting for traditional clinical risk factors, the top quintile of LA diameter/height was significantly related to ischemic stroke (HR 1.7; 95% CI: 1.1, 2.7) and all-cause mortality (HR 2.0; 95% CI: 1.5, 2.7). After further adjustment for left ventricular (LV) hypertrophy and low LV ejection fraction, the top quintile remained significantly related to all-cause mortality (HR 1.8; 95% CI: 1.3, 2.5). Conclusions In this population-based cohort of African Americans, LA size was a predictor of all-cause mortality after adjusting for traditional cardiovascular risk factors, LV hypertrophy, and low LV ejection fraction.

BackgroundAfrican Americans have an increased incidence and worse prognosis with chronic kidney disease (CKD - estimated glomerular filtration rate [eGFR] <60 ml/min/1.73 m2) than their counterparts of European-descent. Inflammation has been related to renal disease in non-Hispanic whites, but there are limited data on the role of inflammation in renal dysfunction in African Americans in the community.MethodsWe examined the cross-sectional relation of log transformed C-reactive protein (CRP) to renal function (eGFR by Modification of Diet and Renal Disease equation) in African American participants of the community-based Jackson Heart Study's first examination (2000 to 2004). We conducted multivariable linear regression relating CRP to eGFR adjusting for age, sex, body mass index, systolic and diastolic blood pressure, diabetes, total/HDL cholesterol, triglycerides, smoking, antihypertensive therapy, lipid lowering therapy, hormone replacement therapy, and prevalent cardiovascular disease events. In a secondary analysis we assessed the association of CRP with albuminuria (defined as albumin-to-creatinine ratio > 30 mg/g).ResultsParticipants (n = 4320, 63.2% women) had a mean age ± SD of 54.0 ± 12.8 years. The prevalence of CKD was 5.2% (n = 228 cases). In multivariable regression, CRP concentrations were higher in those with CKD compared to those without CKD (mean CRP 3.2 ± 1.1 mg/L vs. 2.4 ± 1.0 mg/L, respectively p < 0.0001). CRP was significantly associated with albuminuria in sex and age adjusted model however not in the multivariable adjusted model (p > 0.05).ConclusionCRP was associated with CKD however not albuminuria in multivariable-adjusted analyses. The study of inflammation in the progression of renal disease in African Americans merits further investigation.

Background Lower plasma B-type natriuretic peptide (BNP) concentrations in obese individuals (‘natriuretic handicap’) may play a role in the pathogenesis of obesity-related hypertension. Whether this phenomenon may contribute to hypertension in African Americans is unknown. We tested the hypothesis that body mass index (BMI) is inversely related to BNP concentrations in African Americans. Methods and Results We examined the relation of plasma BNP to BMI in 3,742 Jackson Heart Study participants (mean age: 55±13, 62% women) without heart failure using multivariable linear and logistic regression, adjusting for clinical and echocardiographic covariates. The multivariable adjusted mean BNP was higher for lean participants compared to obese participants in both normotensive (p<0.0001) and hypertensive (p<0.0012) groups. In sex-specific analyses, the adjusted mean BNP was higher in lean-hypertensive individuals compared to obese-hypertensive individuals for both men (20.5 pg/mL vs. 10.9 pg/mL; p=0.0009) and women (20.0 pg/mL vs. 13.8 pg/mL; p=0.011) respectively. The differences between lean and obese participants were more pronounced in normotensive participants (men, 9.0 pg/mL vs. 4.4 pg/mL; p<0.0001 and women, 12.8 pg/mL vs. 8.4 pg/mL; p=0.0005). For both hypertensive and normotensive individuals in the pooled sample, multivariable adjusted BNP was significantly related to both continuous BMI (p<0.05 and p<0.0001 respectively) and categorical BMI (p for trend <0.006 and <0.0001 respectively). Conclusion Our cross-sectional study of a large community-based sample of African-Americans demonstrates that higher BMI is associated with lower circulating BNP concentrations, thereby extending the concept of a ‘natriuretic handicap’ in obese individuals observed in non-Hispanic whites to this high-risk population.