Biomarkers and degree of atherosclerosis are independently associated with incident atherosclerotic cardiovascular disease in a primary prevention cohort: The ARIC study

Biomarkers and atherosclerosis imaging have been studied individually for association with incident cardiovascular disease (CVD); however, limited data exist on whether the biomarkers are associated with events with a similar magnitude in the presence of atherosclerosis. In this study, we assessed whether the presence of atherosclerosis as measured by carotid intima media thickness (cIMT) affects the association between biomarkers known to be associated with coronary heart disease (CHD) and incident cardiovascular disease (CVD) in a primary prevention cohort

Reduced Neutrophil Count in People of African Descent Is Due To a Regulatory Variant in the Duffy Antigen Receptor for Chemokines Gene

Persistently low white blood cell count (WBC) and neutrophil count is a well-described phenomenon in persons of African ancestry, whose etiology remains unknown. We recently used admixture mapping to identify an approximately 1-megabase region on chromosome 1, where ancestry status (African or European) almost entirely accounted for the difference in WBC between African Americans and European Americans. To identify the specific genetic change responsible for this association, we analyzed genotype and phenotype data from 6,005 African Americans from the Jackson Heart Study (JHS), the Health, Aging and Body Composition (Health ABC) Study, and the Atherosclerosis Risk in Communities (ARIC) Study. We demonstrate that the causal variant must be at least 91% different in frequency between West Africans and European Americans. An excellent candidate is the Duffy Null polymorphism (SNP rs2814778 at chromosome 1q23.2), which is the only polymorphism in the region known to be so differentiated in frequency and is already known to protect against Plasmodium vivax malaria. We confirm that rs2814778 is predictive of WBC and neutrophil count in African Americans above beyond the previously described admixture association (P = 3.8×10^−5), establishing a novel phenotype for this genetic variant

Pre-Morbid Body Mass Index and Mortality After Incident Heart Failure

Although obesity is an independent risk factor for heart failure (HF), once HF is established, obesity is associated with lower mortality. It is unclear if the weight loss due to advanced HF leads to this paradoxical finding

Reduced Neutrophil Count in People of African Descent Is Due To a Regulatory Variant in the Duffy Antigen Receptor for Chemokines Gene

Persistently low white blood cell count (WBC) and neutrophil count is a well-described phenomenon in persons of African ancestry, whose etiology remains unknown. We recently used admixture mapping to identify an approximately 1-megabase region on chromosome 1, where ancestry status (African or European) almost entirely accounted for the difference in WBC between African Americans and European Americans. To identify the specific genetic change responsible for this association, we analyzed genotype and phenotype data from 6,005 African Americans from the Jackson Heart Study (JHS), the Health, Aging and Body Composition (Health ABC) Study, and the Atherosclerosis Risk in Communities (ARIC) Study. We demonstrate that the causal variant must be at least 91% different in frequency between West Africans and European Americans. An excellent candidate is the Duffy Null polymorphism (SNP rs2814778 at chromosome 1q23.2), which is the only polymorphism in the region known to be so differentiated in frequency and is already known to protect against Plasmodium vivax malaria. We confirm that rs2814778 is predictive of WBC and neutrophil count in African Americans above beyond the previously described admixture association (P = 3.8×10−5), establishing a novel phenotype for this genetic variant

Genetic associations at 53 loci highlight cell types and biological pathways relevant for kidney function.

Reduced glomerular filtration rate defines chronic kidney disease and is associated with cardiovascular and all-cause mortality. We conducted a meta-analysis of genome-wide association studies for estimated glomerular filtration rate (eGFR), combining data across 133,413 individuals with replication in up to 42,166 individuals. We identify 24 new and confirm 29 previously identified loci. Of these 53 loci, 19 associate with eGFR among individuals with diabetes. Using bioinformatics, we show that identified genes at eGFR loci are enriched for expression in kidney tissues and in pathways relevant for kidney development and transmembrane transporter activity, kidney structure, and regulation of glucose metabolism. Chromatin state mapping and DNase I hypersensitivity analyses across adult tissues demonstrate preferential mapping of associated variants to regulatory regions in kidney but not extra-renal tissues. These findings suggest that genetic determinants of eGFR are mediated largely through direct effects within the kidney and highlight important cell types and biological pathways

Pre-morbid body mass index and mortality after incident heart failure: the ARIC Study

Background: Although obesity is an independent risk factor for heart failure (HF), once HF is established, obesity is associated with lower mortality. It is unclear if the weight loss due to advanced HF leads to this paradoxical finding.Objectives: This study sought to evaluate the prognostic impact of pre-morbid obesity in patients with HF.Methods: In the ARIC (Atherosclerosis Risk In Communities) study, we used body mass index (BMI) measured ≥6 months before incident HF (pre-morbid BMI) to evaluate the association of overweight (BMI 25 to /m(2)) and obesity (BMI ≥30 kg/m(2)) compared with normal BMI (18.5 to /m(2)) with mortality after incident HF.Results: Among 1,487 patients with incident HF, 35% were overweight and 47% were obese by pre-morbid BMI measured 4.3 ± 3.1 years before HF diagnosis. Over 10-year follow-up after incident HF, 43% of patients died. After adjustment for demographics and comorbidities, being pre-morbidly overweight (hazard ratio [HR]: 0.72; 95% confidence interval [CI]: 0.58 to 0.90; p = 0.004) or obese (HR: 0.70; 95% CI: 0.56 to 0.87; p = 0.001) had a protective association with survival compared with normal BMI. The protective effect of overweight and obesity was consistent across subgroups on the basis of a history of cancer, smoking, and diabetes.Conclusions: Our results, for the first time, demonstrate that patients who were overweight or obese before HF development have lower mortality after HF diagnosis compared with normal BMI patients. Thus, weight loss due to advanced HF may not completely explain the protective effect of higher BMI in HF patients

Biomarkers and degree of atherosclerosis are independently associated with incident atherosclerotic cardiovascular disease in a primary prevention cohort: The ARIC study

Background and aims: Biomarkers and atherosclerosis imaging have been studied individually for association with incident cardiovascular disease (CVD); however, limited data exist on whether the biomarkers are associated with events with a similar magnitude in the presence of atherosclerosis. In this study, we assessed whether the presence of atherosclerosis as measured by carotid intima media thickness (cIMT) affects the association between biomarkers known to be associated with coronary heart disease (CHD) and incident cardiovascular disease (CVD) in a primary prevention cohort.Methods: 8127 participants from the ARIC study (4th visit, 1996-1998) were stratified as having minimal, mild, or substantial atherosclerosis by cIMT. Levels of C-reactive protein, lipoprotein-associated phospholipase A2, cardiac troponin T, N-terminal pro-brain natriuretic peptide, lipoprotein(a), cystatin C, and urine albumin to creatinine ratio were measured in each participant. Hazard ratios were used to determine the relationship between the biomarkers and incident CHD, stroke, and CVD in each category of atherosclerosis.Results: While each of the biomarkers was significantly associated with risk of events overall, we found no significant differences noted in the strength of association of biomarkers with CHD, stroke, and CVD when analyzed by degree of atherosclerosis.Conclusions: These findings suggest that the level of atherosclerosis does not significantly influence the association between biomarkers and CVD

Effects of rare and common blood pressure gene variants on essential hypertension: results from the Family Blood Pressure Program, CLUE, and Atherosclerosis Risk in Communities studies

Hypertension affects ≈30% of adults in industrialized countries and is the major risk factor for cardiovascular disease