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Donna K Arnett

Publications and source records attributed to Donna K Arnett.

At least 19 recordsLinked to original sources

Influence of Ancestral and Geographic Factors on Intracerebral Hemorrhage Risks Among Africans and Americans.

BACKGROUND: We investigated whether risk factors for intracerebral hemorrhage (ICH) among indigenous Africans (IA) would vary in prevalence and effect compared with self-reported African, Hispanic, and White Americans by comparing data from 2 independent population-based case-control studies conducted in West Africa and the United States. METHODS: We compared ICH risk factors common to the SIREN (Stroke Investigative Research and Educational Network: 1100 case-control pairs) and the ERICH (Ethnic/Racial Variation of Intracerebral Hemorrhage: 999 case-control pairs African American participants, 998 case-control pairs, Hispanic Americans, 1000 case-control pairs, White Americans) studies. Ethnicity/Race was self-reported. The effect measure of interest is the odds ratio (OR). To test for differences in the effects of the risk factors between the SIREN IA study population and each of the ERICH study populations, a test for heterogeneity was computed using the R program, metagen (version 4.9-6). RESULTS: ICH occurred at a younger age among IA (54.3±13.4 years), African Americans (58.0±12.7), and Hispanic Americans (58.9±14.3), compared with White Americans (69.1±13.9). The largest distinction was for hypertension, where IA exhibited a much larger risk of ICH than the American study population (OR, 67.02 [95% CI, 33.30-134.85]), African American (OR, 3.71 [95% CI, 2.53-5.44]); Hispanic (OR, 3.55 [95% CI, 2.54-4.92]), and White population (OR, 2.69 [95% CI, 1.95-3.69]). Current alcohol use exhibited increased risk in IA (OR, 2.24 [95% CI, 1.36-3.67]), but not in African Americans (OR, 0.63 [95% CI, 0.46-0.86]), Hispanic (OR, 0.87 [95% CI, 0.65-1.17]), and White Americans (OR, 0.51 [95% CI, 0.38-0.69]). CONCLUSIONS: Identical or comparable risk factors do not consistently result in the same disease risk across different cultures and regions. Therefore, to improve our understanding of the genetic determinants and biological pathways driving ICH risk, it is crucial to study multiple populations, including IA, while accounting for the influence of environmental and social factors.

Adult↗

Whole genome sequence analysis of low-density lipoprotein cholesterol across 246 K individuals.

BACKGROUND: Rare genetic variation provided by whole genome sequence datasets has been relatively less explored for its contributions to human traits. Meta-analysis of sequencing data offers advantages by integrating larger sample sizes from diverse cohorts, thereby increasing the likelihood of discovering novel insights into complex traits. Furthermore, emerging methods in genome-wide rare variant association testing further improve power and interpretability. RESULTS: Here, we conduct the largest meta-analysis of whole genome sequencing for low-density lipoprotein cholesterol (LDL-C), a therapeutic target for coronary artery disease, analyzing data from 246 K participants and integrating 1.23B variants from the UK Biobank and the Trans-Omics for Precision Medicine (TOPMed) program. We identify numerous rare coding and non-coding gene associations related to LDL-C, with replication across 86 K participants in All of Us. Our findings are based on single-variant analyses, rare coding and non-coding variant aggregation tests, and sliding window approaches. Through this comprehensive analysis, we identify 704 novel single-variant associations, 25 novel rare coding variant aggregates, 28 novel rare non-coding variant aggregates, and one novel sliding window aggregate. CONCLUSIONS: This study provides a meta-analysis framework for large-scale whole genome sequence association analyses from diverse population groups, yielding novel rare non-coding variant associations.

Humans↗

Whole genome sequence-based association analysis of African American individuals with bipolar disorder and schizophrenia.

In studies of individuals of primarily European genetic ancestry, common and low-frequency variants and rare coding variants have been found to be associated with the risk of bipolar disorder (BD) and schizophrenia (SZ). However, less is known for individuals of other genetic ancestries or the role of rare non-coding variants in BD and SZ risk. We performed whole genome sequencing of African American individuals: 1,598 with BD, 3,295 with SZ, and 2,651 unaffected controls (InPSYght study). We increased power by incorporating 14,812 jointly called psychiatrically unscreened ancestry-matched controls from the Trans-Omics for Precision Medicine (TOPMed) Program for a total of 17,463 controls. To identify variants and sets of variants associated with BD and/or SZ, we performed single-variant tests, gene-based tests for singleton protein truncating variants, and rare and low-frequency variant annotation-based tests with conservation and universal chromatin states and sliding windows. We found suggestive evidence of BD association with single-variants on chromosome 18 and of lower BD risk associated with rare and low-frequency variants on chromosome 11 in a region with multiple BD GWAS loci, using a sliding window approach. We also found that chromatin and conservation state tests can be used to detect differential calling of variants in controls sequenced at different centers and to assess the effectiveness of sequencing metric covariate adjustments. Our findings reinforce the need for continued whole genome sequencing in additional samples of African American individuals and more comprehensive functional annotation of non-coding variants.

Journal Article↗

Rare variant contribution to the heritability of coronary artery disease.

Whole genome sequences (WGS) enable discovery of rare variants which may contribute to missing heritability of coronary artery disease (CAD). To measure their contribution, we apply the GREML-LDMS-I approach to WGS of 4949 cases and 17,494 controls of European ancestry from the NHLBI TOPMed program. We estimate CAD heritability at 34.3% assuming a prevalence of 8.2%. Ultra-rare (minor allele frequency ≤ 0.1%) variants with low linkage disequilibrium (LD) score contribute ~50% of the heritability. We also investigate CAD heritability enrichment using a diverse set of functional annotations: i) constraint; ii) predicted protein-altering impact; iii) cis-regulatory elements from a cell-specific chromatin atlas of the human coronary; and iv) annotation principal components representing a wide range of functional processes. We observe marked enrichment of CAD heritability for most functional annotations. These results reveal the predominant role of ultra-rare variants in low LD on the heritability of CAD. Moreover, they highlight several functional processes including cell type-specific regulatory mechanisms as key drivers of CAD genetic risk.

Humans↗

Whole-genome sequencing in 333,100 individuals reveals rare non-coding single variant and aggregate associations with height.

The role of rare non-coding variation in complex human phenotypes is still largely unknown. To elucidate the impact of rare variants in regulatory elements, we performed a whole-genome sequencing association analysis for height using 333,100 individuals from three datasets: UK Biobank (N&#x2009;=&#x2009;200,003), TOPMed (N&#x2009;=&#x2009;87,652) and All of Us (N&#x2009;=&#x2009;45,445). We performed rare (&#x2009;<&#x2009;0.1% minor-allele-frequency) single-variant and aggregate testing of non-coding variants in regulatory regions based on proximal-regulatory, intergenic-regulatory and deep-intronic annotation. We observed 29 independent variants associated with height at P&#x2009;<&#x2009;after conditioning on previously reported variants, with effect sizes ranging from -7cm to +4.7&#x2009;cm. We also identified and replicated non-coding aggregate-based associations proximal to HMGA1 containing variants associated with a 5&#x2009;cm taller height and of highly-conserved variants in MIR497HG on chromosome 17. We have developed an approach for identifying non-coding rare variants in regulatory regions with large effects from whole-genome sequencing data associated with complex traits.

Humans↗

A methylation risk score for chronic kidney disease: a HyperGEN study.

Chronic kidney disease (CKD) impacts about 1 in 7 adults in the United States, but African Americans (AAs) carry a disproportionately higher burden of disease. Epigenetic modifications, such as DNA methylation at cytosine-phosphate-guanine (CpG) sites, have been linked to kidney function and may have clinical utility in predicting the risk of CKD. Given the dynamic relationship between the epigenome, environment, and disease, AAs may be especially sensitive to environment-driven methylation alterations. Moreover, risk models incorporating CpG methylation have been shown to predict disease across multiple racial groups. In this study, we developed a methylation risk score (MRS) for CKD in cohorts of AAs. We selected nine CpG sites that were previously reported to be associated with estimated glomerular filtration rate (eGFR) in epigenome-wide association studies to construct a MRS in the Hypertension Genetic Epidemiology Network (HyperGEN). In logistic mixed models, the MRS was significantly associated with prevalent CKD and was robust to multiple sensitivity analyses, including CKD risk factors. There was modest replication in validation cohorts. In summary, we demonstrated that an eGFR-based CpG score is an independent predictor of prevalent CKD, suggesting that MRS should be further investigated for clinical utility in evaluating CKD risk and progression.

Humans↗

Genome-wide linkage mapping for valve calcification susceptibility loci in hypertensive sibships: the Hypertension Genetic Epidemiology Network Study.

It remains unclear whether genetic factors contribute to the susceptibility to valve calcification. Accordingly, echocardiograms and genotyping were performed in 1871 hypertensive siblings who participated in the Hypertension Genetic Epidemiology Network Study. Genome-wide affected sibpair nonparametric linkage analysis was conducted using the allele-sharing method implemented in the Merlin computer program. A total of 1014 sibships from 858 families were evaluated for aortic valve sclerosis or mitral annular calcification. Of these, 78 sibships from 68 families contained > or =2 affected siblings with > or =1 type of valve calcification (142 affected siblings). All 3 of the traits showed a modest degree of familial aggregation, with sibling recurrence risk (SD) and sibling recurrence risk ratio (95% CI) being 0.25 (0.035) and 2.31 (1.72 to 3.11) for aortic valve sclerosis, 0.25 (0.035) and 1.78 (1.36 to 2.33) for mitral annular calcification, and 0.31 (0.030) and 1.52 (1.24 to 1.85) for aortic valve sclerosis and mitral annular calcification, respectively. Affected sibpair linkage analysis revealed the highest logarithm of odds score (3.14) in chromosome 16 at 105.6 cM for aortic valve sclerosis. Other chromosomal regions with logarithm of odds score > or =1.9 were found in chromosomes 19 (2.88), 16 (2.63), 1 (2.12), and 2 (2.03) for aortic valve sclerosis and chromosome 13 (2.12) for any valve calcification. There was no logarithm of odds score > or =1.9 for mitral annular calcification. Our study shows strong linkage of aortic valve sclerosis to chromosome 16q22.1-q22.3 and suggestive linkage to chromosome 19p13.11-p11 and identifies several other promising genomic regions that may contain specific susceptibility loci for valve calcification.

Adult↗

Absence of an interaction between the angiotensin-converting enzyme insertion-deletion polymorphism and pravastatin on cardiovascular disease in high-risk hypertensive patients: the Genetics of Hypertension-Associated Treatment (GenHAT) study.

BACKGROUND: The aim of this study was to determine whether the angiotensin-converting enzyme (ACE) insertion-deletion (ID) polymorphism interacts with pravastatin to modify the risk of coronary heart disease (CHD) and other cardiovascular end points in a large clinical trial. METHODS: GenHAT is an ancillary study of the ALLHAT. The ACE ID genotyped population in the lipid-lowering arm of ALLHAT included 9467 participants randomly assigned to pravastatin (n = 4741) or to usual care (n = 4726). The efficacy of pravastatin in reducing the risk of primary outcome (all-cause mortality) and secondary outcomes (fatal CHD and nonfatal myocardial infarction, cardiovascular disease [CVD] mortality, CHD, stroke, other CVD, non-CVD mortality, stroke, and heart failure) was compared between the genotype strata (dominant model ID + II vs DD, additive model II vs ID vs DD), by examining an interaction term in a Cox proportional hazards model. RESULTS: The relative risk of fatal CHD and nonfatal myocardial infarction among subjects randomized to pravastatin compared with subjects randomized to usual care was similar in subjects with the II genotype (hazard ratio [HR] 0.84, 95% CI 0.59-1.18), the ID genotype (HR 0.84, 95% CI 0.68-1.03), and the DD genotype (HR 0.99, 95% CI 0.77-1.27). CONCLUSIONS: We found no evidence that the ACE ID genotype was a major modifier of the efficacy of pravastatin in reducing the risk of cardiovascular events.

Aged↗

Genotype-by-sex interaction on fasting insulin concentration: the HyperGEN study.

Recent studies have demonstrated the importance of sex effects on the underlying genetic architecture of insulin-related traits. To explore sex-specific genetic effects on fasting insulin, we tested for genotype-by-sex interaction and conducted linkage analysis of fasting insulin in Hypertension Genetic Epidemiology Network families. Hypertensive siblings and their first-degree relatives were recruited from five field centers. We performed a genome scan for quantitative trait loci influencing fasting insulin among 1,505 European Americans and 1,616 African Americans without diabetes. Sex-stratified linear regression models, adjusted for race, center, and age, were explored. The Mammalian Genotyping Service typed 391 microsatellite markers, spaced roughly 9 cM. Variance component linkage analysis was performed in SOLAR using ethnic-specific marker allele frequencies and multipoint IBDs calculated in MERLIN. We detected a quantitative trait locus influencing fasting insulin in female subjects (logarithm of odds [LOD] = 3.4) on chromosome 2 at 95 cM (between GATA69E12 and GATA71G04) but not in male subjects (LOD = 0.0, P for interaction = 0.007). This sex-specific signal at 2p13.2 was detected in both European-American (LOD = 2.1) and African-American (LOD = 1.2) female subjects. Our findings overlap with several other linkage reports of insulin-related traits and demonstrate the importance of considering complex context-dependent interactions in the search for insulin-related genes.

Alcohol Drinking↗

Genome scan of glomerular filtration rate and albuminuria: the HyperGEN study.

BACKGROUND: Albuminuria and reduced glomerular filtration rate (GFR) are markers of renal dysfunction associated with hypertension. We performed genome-wide scans to detect loci impacting these parameters in 1251 African American (AAs) and 1129 European American (EAs) hypertensive siblings from the Hypertension Genetic Epidemiology Network study. METHODS: GFR, estimated by the Modification of Diet in Renal Disease equation, and albuminuria, measured as albumin to creatinine ratio (ACR), were adjusted for gender, age, centre, mean blood pressure, anti-hypertensive medication class and diabetes status using SOLAR. Since albuminuria and abnormal GFR often coexist, we conducted bivariate linkage analyses to investigate the presence of pleiotropy. RESULTS: The phenotypic correlation between ACR and GFR was not significant in EAs (r = 0.04) and significantly negative in AAs (r = -0.17). Univariate analyses of ACR showed suggestive evidence of linkage on chromosomes 8, 16 and 17 (LOD: 2-2.8) in AAs, on chromosomes 18 and 19 (LOD = 2) in EAs, and on chromosome 19 (LOD = 2.6) when combining AAs and EAs. For GFR, suggestive linkage was found on chromosomes 7, 14 and 19 (LOD: 2.2-2.9) in AAs and on chromosomes 14, 15 and 16 (LOD: 2.1-3.3) in the combined group. Also, bivariate analyses showed a LOD score of 3.4 at 133 cM on chromosome 7 in AAs. CONCLUSIONS: Suggestive evidence for linkage to GFR and ACR was observed at many loci. The findings are consistent with previous studies. Also, indication of a pleiotropic locus was detected in chromosome 7 in AAs.

Albumins↗

Traditional cardiovascular risk factors in relation to left ventricular mass, volume, and systolic function by cardiac magnetic resonance imaging: the Multiethnic Study of Atherosclerosis.

OBJECTIVES: The goal of this study was to examine the cross-sectional associations of cardiovascular risk factors with left ventricular (LV) geometry and systolic function measured by cardiac magnetic resonance imaging (MRI) in the Multiethnic Study of Atherosclerosis (MESA). BACKGROUND: Cardiovascular risk factors including hypertension, smoking, and obesity are known to be associated with increased LV mass, but less is known about the association of risk factors with LV systolic function, particularly in populations without clinical cardiovascular disease. METHODS: Participants were from 4 racial/ethnic groups and were free of clinical cardiovascular disease. Blood pressure, health habits, body mass index, lipid levels, and glucose abnormalities were assessed and MRI exams performed at baseline (n = 4,869). Multivariable linear regression was used to model the association of risk factors with LV mass, end-diastolic volume, stroke volume, ejection fraction, and cardiac output. RESULTS: The mean age was 62 years, and 52% of the participants were women. After adjustment for sociodemographic variables and height, higher systolic blood pressure and body mass index were associated with larger LV mass and volumes. Current smoking and diabetes were associated with greater LV mass (+7.7 g, 95% confidence interval [CI] +5.5 to +9.9 and +3.5 g, 95% CI +1.2 to +5.8, respectively), and with lower stroke volume (-1.9 ml, 95% CI -3.3 to -0.5 and -4.5 ml, 95% CI -6.0 to -3.0, respectively) and lower ejection fraction (-1.6%, 95% CI -2.1 to -1.0 and -0.8%, 95% CI -1.5 to -0.2, respectively). CONCLUSIONS: In this cohort free of clinical cardiovascular disease, modifiable risk factors were associated with subclinical alterations in LV size and systolic function as detected by cardiac MRI.

Black or African American↗

Diabetes, gender, and left ventricular structure in African-Americans: the atherosclerosis risk in communities study.

BACKGROUND: Cardiovascular risk associated with diabetes may be partially attributed to left ventricular structural abnormalities. However, the relations between left ventricular structure and diabetes have not been extensively studied in African-Americans. METHODS: We studied 514 male and 965 female African-Americans 51 to 70 years old, in whom echocardiographic left ventricular mass measurements were collected for the ARIC Study. In these, we investigated the independent association of diabetes with left ventricular structural abnormalities. RESULTS: Diabetes, hypertension and obesity prevalences were 22%, 57% and 45%, respectively. Unindexed left ventricular mass was higher with diabetes in both men (238.3 +/- 79.4 g vs. 213.7 +/- 58.6 g; p < 0.001) and women (206.4 +/- 61.5 g vs. 176.9 +/- 50.1 g; p < 0.001), respectively. Prevalence of height-indexed left ventricular hypertrophy was higher in women while increased relative wall thickness was similar in men and women. Those with diabetes had higher prevalences of height-indexed left ventricular hypertrophy (52% vs. 32%; p < 0.001), and of increased relative wall thickness (73% vs. 64%; p = 0.002). Gender-adjusted associations of diabetes with left ventricular hypertrophy (OR = 2.29 95% CI:1.79-2.94) were attenuated after multiple adjustments in logistic regression (OR = 1.50 95% CI:1.12-2.00). Diabetes was associated with higher left ventricle diameter (OR = 2.13 95% CI:1.28-3.53) only in men and with higher wall thickness (OR = 1.89 95% CI:1.34-2.66) only in women. Attenuations in diabetes associations were frequently seen after adjustment for obesity indices. CONCLUSION: In African-Americans, diabetes is associated with left ventricular hypertrophy and, with different patterns of left ventricular structural abnormalities between genders. Attenuation seen in adjusted associations suggests that the higher frequency of structural abnormalities seen in diabetes may be due to factors other than hyperglycemia.

Black or African American↗

Genome-wide linkage scans for loci affecting total cholesterol, HDL-C, and triglycerides: the Family Blood Pressure Program.

Atherosclerosis accounts for 75% of all deaths from cardiovascular disease and includes coronary heart disease (CHD), stroke, and other diseases of the arteries. More than half of all CHD is attributable to abnormalities in levels and metabolism of lipids. To locate genes that affect total cholesterol, high density lipoprotein cholesterol (HDL-C), and triglycerides, genome-wide linkage scans for quantitative trait loci were performed using variance components methods as implemented in SOLAR on a large diverse sample recruited as part of the Family Blood Pressure Program. Phenotype and genetic marker data were available for 9,299 subjects in 2,953 families for total cholesterol, 8,668 subjects in 2,736 families for HDL, and 7,760 subjects in 2,499 families for triglycerides. Mean lipid levels were adjusted for the effects of sex, age, age2, age-by-sex interaction, body mass index, smoking status, and field center. HDL-C and triglycerides were further adjusted for average total alcoholic drinks per week and estrogen use. Significant linkage was found for total cholesterol on chromosome 2 (LOD=3.1 at 43 cM) in Hispanics and for HDL-C on chromosome 3 (LOD=3.0 at 182 cM) and 12 (LOD=3.5 at 124 cM) in Asians. In addition, there were 13 regions that showed suggestive linkage (LOD >or= 2.0); 7 for total cholesterol, 4 for HDL, and 2 for triglycerides. The identification of these loci affecting lipid phenotypes and the apparent congruence with previous linkage results provides increased support that these regions contain genes influencing lipid levels.

Adult↗

Alcohol consumption and plasma atrial natriuretic peptide (from the HyperGEN study).

Although moderate alcohol consumption has been associated with a lower risk of cardiovascular disease, underlying physiologic mechanisms are not fully understood. Data relating alcohol intake to atrial natriuretic peptide (ANP) have been inconsistent. We evaluated whether alcohol consumption was associated with plasma ANP in 1,345 participants from the Hypertension Genetic Epidemiology Network (HyperGEN) study. We used random effect models to estimate the adjusted means of logarithmic transformed ANP. The mean age was 35.8 +/- 8.6 years, 91% were normotensive, 46% were men, and 40% and 60% were African-Americans and whites, respectively. In a model adjusting for age, body mass index, field center, education, gender, race, and serum albumin, alcohol consumption was positively associated with ANP in men (p < 0.0001 for trend) and women (p = 0.0014) and in African-Americans (p = 0.006) and whites (p < 0.0001). The adjusted mean of log-transformed ANP was 3.68, 3.67, 3.77, 3.76, 3.86, and 3.91 pg/ml in lifetime abstainers, former drinkers, and current drinkers of 1 to 6, 7 to 12, 13 to 24, and > 24 g/d, respectively. Controlling for additional factors, including left atrial size, ejection fraction, left ventricular mass, end-diastolic volume, systolic blood pressure, smoking, lipids, and serum creatinine did not change the results. Restriction to normotensive subjects yielded similar results. Alcohol intake was associated positively with systolic and diastolic blood pressure (p < 0.0001 each for trend). In conclusion, our data have shown a positive and linear association between alcohol consumption and ANP in men and women, irrespective of race.

Adolescent↗

Association of coronary artery calcified plaque with clinical coronary heart disease in the National Heart, Lung, and Blood Institute's Family Heart Study.

The presence of calcified coronary artery plaque has shown variable association with clinical coronary heart disease (CHD), particularly after adjustment for other risk factors. From 2002 to 2004, as part of the National Heart, Lung, and Blood Institute's Family Heart Study, coronary artery calcium (CAC) scans by 4-slice multidetector computed tomography were performed in 3,359 subjects, including 389 with clinically diagnosed CHD. Among these was a cohort of 2,254 patients who had been asymptomatic at an initial examination 7 to 9 years previously (1994 to 1996), with 111 who had developed newly diagnosed, nonfatal CHD since the initial examination. In cross-sectional analyses, we examined associations between CAC and CHD in the entire group and in the subgroup seen at the initial examination. In the 2 sets of analyses, odds ratios for CHD ranged from approximately 4 in those with CAC scores of 100 to 199 (p <0.01) to >20 in those with CAC scores >/=1,000 (p <0.0001) compared with those with no measurable CAC. This steep gradient of risk persisted after adjustment for risk factors. A quantitative CHD family history score was significantly associated with CHD even after adjusting for all standard risk factors and including CAC in the model. In conclusion, CAC was strongly associated with CHD even after adjustment for standard risk factors and family history contributed independently to CHD risk.

Adult↗

Racial differences in the association of coronary calcified plaque with left ventricular hypertrophy: the National Heart, Lung, and Blood Institute Family Heart Study and Hypertension Genetic Epidemiology Network.

Studies have reported a lower burden of calcified atherosclerotic plaque in coronary arteries in African-Americans than in whites. Findings from autopsy studies of sudden cardiac death have suggested a link between left ventricular hypertrophy and severity of coronary atherosclerosis. Echocardiograms and cardiac computed tomograms were analyzed in 334 African-American (84% hypertensive) and 196 white (66% hypertensive) adults with no history of coronary heart disease or revascularization procedures at study entry. The relation of coronary artery calcium (CAC) score to left ventricular mass and left ventricular mass indexed to body surface area was assessed by Spearman's correlations and mixed linear models. Covariates included age, gender, field center, weight, height, systolic blood pressure, number of antihypertensive medications, diabetes, total and high-density lipoprotein cholesterol levels, and current smoking and alcohol consumption. In African-Americans, a significant and independent association between CAC score and left ventricular mass or left ventricular mass indexed to body surface area was present with the 2 analytic strategies. Spearman's correlation coefficients for CAC score with left ventricular mass and left ventricular mass indexed to body surface area were 0.14 (p = 0.015) and 0.13 (p = 0.025), respectively, after multivariable adjustment. In whites, the associations of CAC score with measurements of left ventricular mass were weaker and only marginally significant in mixed linear models. In conclusion, these findings suggest that CAC reflects a different risk burden between African-Americans and whites, and future studies examining the prognostic implications of CAC in African-Americans should consider the potential association between CAC and left ventricular hypertrophy.

Aged↗

Evidence of QTL on 15q21 for high-density lipoprotein cholesterol: the National Heart, Lung, and Blood Institute Family Heart Study (NHLBI FHS).

A genome-wide linkage scan was conducted to identify regions potentially having quantitative trait loci (QTLs) influencing high-density lipoprotein (HDL) cholesterol. We found suggestive evidence of a QTL (lod score (LOD)=1.75, p=0.00224, and q=0.07649) influencing the variation of plasma levels of age- and sex-adjusted HDL-cholesterol on chromosome 15q21 at marker D15S659 in the NHLBI FHS data. Owing to the perturbations to lipid profiles associated with diabetes, the analysis was repeated excluding diabetic subjects from the sample. The lod score increased from 1.75 to 2.71 (p=0.00021, q=0.05392) at the same chromosome 15 location, despite the reduction in sample size. This finding indicates that the inclusion of diabetic subjects in the analysis may confound the presence of a QTL for HDL-cholesterol on 15q21. Because of the known effects of important covariates such as metabolic variables and lifestyle habits that may interact with a putative QTL, we also analyzed HDL-cholesterol with a progressive adjustment. When body mass index, smoking, and habitual alcohol intake were added to age- and sex-adjustment, we found strong evidence for linkage in the complete sample (LOD=4.77, p=0.0000013, and q=0.00016) as well as in the non-diabetic sub-sample (LOD=4.52, p=0.0000025, and q=0.00026) on chromosome 15q21 (between D15S659 and D15S195 markers). These results suggest that there are multiple pathways and factors involving genetic and environmental effects influencing HDL-cholesterol levels, and by taking some of these known factors into account, we obtained strong evidence of a QTL influencing HDL-cholesterol levels. While this putative QTL may also have an effect in diabetes, our data suggest a more pronounced role in non-diabetics. A prominent candidate gene residing within the linkage region on 15q21 is hepatic lipase (HL), which has a major role in lipoprotein metabolism.

Adult↗

Hypertension and smoking are associated with reduced regional left ventricular function in asymptomatic: individuals the Multi-Ethnic Study of Atherosclerosis.

OBJECTIVES: This study sought to test the hypothesis that reduced regional left ventricular (LV) function is associated with traditional risk factors including hypertension, hypercholesterolemia, and smoking in asymptomatic individuals. BACKGROUND: Coronary artery disease is the main etiology of congestive heart failure in the U.S. and Europe. However, the relationship between risk factors for coronary artery disease and decreased myocardial function has not been studied systematically in asymptomatic individuals. METHODS: The Multi-Ethnic Study of Atherosclerosis (MESA) is a cohort study designed to investigate the nature of atherosclerosis in asymptomatic individuals. A total of 1,184 participants (45 to 84 years old) underwent tagged cardiac magnetic resonance imaging. Regional LV function was quantified by analyzing peak systolic circumferential strain (Ecc) in regions corresponding to the left anterior descending (LAD), circumflex (LCX), and right coronary (RCA) territories. The association between risk factors and strains was studied using multiple linear regression. RESULTS: Higher diastolic blood pressure (DBP) was associated with lower Ecc (p < or = 0.002). The Ecc's in the LAD territory of participants with DBP <80, 80 to 84, 85 to 89, and > or =90 mm Hg were -15.6%, -14.8%, -14.2%, and -13.7%, respectively (p < 0.001). Similar results were documented in other territories and after multivariable analysis. Smokers had lower Ecc in the LAD and RCA regions compared with nonsmokers. Furthermore, dose response relationship between cigarette consumption measured in pack-years and regional LV dysfunction by Ecc was noted (p < or = 0.01 in LAD and RCA territories). Finally, combined diastolic hypertension and smoking was associated with a greater reduction of regional LV function. CONCLUSIONS: Higher diastolic blood pressure and smoking are associated with decreased regional LV function in asymptomatic individuals.

Aged↗