Search

Background: Excess adipose tissue has been implicated in the pathogenesis of insulin resistance and atherosclerosis and is a key risk factor for blood pressure (BP) elevation. However, circulating levels of adiponectin, a protein produced by adipose tissue and widely implicated in the pathogenesis of insulin resistance and atherosclerosis, are inversely proportional to adiposity. The relationship between adiponectin and incident hypertension has not been determined in the general US population.Methods: Normotensive participants (n = 1233) enrolled in the Dallas Heart Study, a multiethnic, probability-based population sample of Dallas County adults were followed for median of 7 years. Retroperitoneal, intraperitoneal, visceral, and subcutaneous adipose tissue were measured at baseline by magnetic resonance imaging. Liver fat content was measured by 1 H-magnetic resonance spectroscopy. Relative risk regression was used to determine the association of adiponectin with incident hypertension after adjustment for age, race, sex, BMI, smoking, diabetes, baseline systolic BP, total cholesterol, and regional fat depot.Results: Of the 1233 study participants (median age 40 years, 40% black, and 56% women), 391 (32%) had developed hypertension over a median follow-up of 7 years. Adiponectin levels were associated with reduced risk of incident hypertension (RR 0.81, 95% CI [0.68-0.96]) in the fully adjusted model, which included liver fat. Similar results were observed after adjustment for subcutaneous or visceral fat depots when tested individually or simultaneously in the model.Conclusion: Our study suggested a protective role of adiponectin against incident hypertension independent of body fat distribution. [ABSTRACT FROM AUTHOR]

Prior reports have associated increased circulating levels of matrix metalloproteinase-9 (MMP-9), an endopeptidase active in the extracellular matrix, with the formation and rupture of aortic aneurysms, raising the possibility that MMP-9 may be a useful diagnostic or therapeutic target for aortic pathology. However, associations between MMP-9 and pathological abdominal aortic phenotypes in the general population have not been reported. In the Dallas Heart Study, a population-based sample of Dallas County residents (n = 2304), we measured MMP-9 and performed magnetic resonance imaging (MRI) of the abdominal aorta, measuring aortic compliance, plaque, wall thickness and luminal diameter. After adjustment for traditional cardiac risk factors and body size, higher MMP-9 quartiles were independently associated with higher aortic wall thickness and larger luminal diameter (p < 0.0001 for each), but not abdominal aortic plaque (p = 0.08), coronary artery calcium (p = 0.20) or the aortic luminal diameter/aortic wall thickness ratio (p = 0.37), supporting the hypothesis that therapies targeting MMP-9 may affect the abdominal aortic wall and modify aortic pathology. [ABSTRACT FROM AUTHOR]

Background: Multiple epidemiological studies from Europe and Asia have demonstrated increased cardiovascular risks associated with isolated elevation of home blood pressure (BP) or masked hypertension (MH). Previous studies have not addressed cardiovascular outcomes associated with MH and white-coat hypertension (WCH) in the general population in the United States.Objectives: The goal of this study was to determine hypertensive target organ damage and adverse cardiovascular outcomes associated with WCH (high clinic BP, ≥140/90 mm Hg; normal home BP, <135/85 mm Hg), MH (high home BP, ≥135/85 mm Hg; normal clinic BP, <140/90 mm Hg), and sustained hypertension (high home and clinic BP) in the DHS (Dallas Heart Study), a large, multiethnic, probability-based population cohort.Methods: Associations among WCH, MH, sustained hypertension, and aortic pulsed wave velocity by magnetic resonance imaging; urinary albumin-to-creatinine ratio; and cystatin C were evaluated at study baseline. Then, associations between WCH and MH with incident cardiovascular outcomes (coronary heart disease, stroke, atrial fibrillation, heart failure, and cardiovascular death) over a median follow-up period of 9 years were assessed.Results: The study cohort comprised 3,027 subjects (50% African Americans). The sample-weighted prevalence rates of WCH and MH were 3.3% and 17.8%, respectively. Both WCH and MH were independently associated with increased aortic pulsed wave velocity, cystatin C, and urinary albumin-to-creatinine ratio. Both WCH (adjusted hazard ratio: 2.09; 95% confidence interval: 1.05 to 4.15) and MH (adjusted hazard ratio: 2.03; 95% confidence interval: 1.36 to 3.03) were independently associated with higher cardiovascular events compared with the normotensive group, even after adjustment for traditional cardiovascular risk factors.Conclusions: In a multiethnic U.S. population, both WCH and MH were independently associated with increased aortic stiffness, renal injury, and incident cardiovascular events. Because MH is common and associated with an adverse cardiovascular profile, home BP monitoring should be routinely performed among U.S. adults. [ABSTRACT FROM AUTHOR]

Background: Cardiovascular disease is a leading economic and medical burden in the United States (US). As an important risk factor for cardiovascular disease, hypertension represents a critical point of intervention. Less is known about longitudinal effects of neighborhood deprivation on blood pressure outcomes, especially in light of new hypertension guidelines., Methods: Longitudinal data from the Dallas Heart Study facilitated multilevel regression analysis of the relationship between neighborhood deprivation, blood pressure change, and incident hypertension over a 9-year period. Factor analysis explored neighborhood perception, which was controlled for in all analyses. Neighborhood deprivation was derived from US Census data and divided into tertiles for analysis. Hypertension status was compared using pre-2017 and 2017 hypertension guidelines., Results: After adjusting for covariates, including moving status and residential self-selection, we observed significant associations between residing in the more deprived neighborhoods and 1) increasing blood pressure over time and 2) incident hypertension. In the fully adjusted model of continuous blood pressure change, significant relationships were seen for both medium (SBP: β = 4.81, SE = 1.39, P = .0005; DBP: β = 2.61, SE = 0.71, P = .0003) and high deprivation (SBP: β = 7.64, SE = 1.55, P < .0001; DBP: β = 4.64, SE = 0.78, P < .0001). In the fully adjusted model of incident hypertension, participants in areas of high deprivation had 1.69 higher odds of developing HTN (OR 1.69; 95% CI 1.02, 2.82), as defined by 2017 hypertension guidelines. Results varied based on definition of hypertension used (pre-2017 vs. 2017 guidelines)., Conclusion: These findings highlight the potential impact of adverse neighborhood conditions on cardiometabolic outcomes, such as hypertension., (Published by Elsevier Inc.)

Large randomized trials have provided inconsistent evidence regarding the benefit of intensive blood pressure (BP) lowering in hypertensive patients. Identifying which patients derive a higher net benefit is essential in informing clinical decision-making. We used patient-level data from 2 trials that tested intensive versus standard BP lowering, Systolic Blood Pressure Intervention Trial (SPRINT) and Action to Control Cardiovascular Risk in Diabetes (ACCORD), to assess whether stratification by cardiovascular disease (CVD) risk will identify patients with a more favorable risk-benefit profile for intensive BP lowering. Within SPRINT, we selected a subset of patients at the extremes of major adverse cardiovascular event rates to develop a decision tree using recursive partitioning modeling. We then validated its predictive effects in the remaining 'intermediate' SPRINT subset (n = 8,357) and externally in ACCORD (n = 2,258). Recursive partitioning produced a 3-variable decision tree model consisting of age ≥74 years, urinary albumin-creatinine ratio ≥34, and history of clinical CVD. It classified 48.6% of SPRINT and 55.3% of ACCORD patients as "high-risk." Compared with standard treatment, intensive BP lowering was associated with lower rates of major adverse cardiovascular event in this high-risk population in both SPRINT cross-validation data (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.52 to 0.85) and ACCORD (HR 0.67, 95% CI 0.50 to 0.90), but not in the remaining low-risk patients (SPRINT: HR 0.83, 95% CI 0.56 to 1.25; ACCORD: HR 1.09, 95% CI 0.64 to 1.83). Additionally, intensive BP lowering did not confer an excess risk of serious adverse events in the high-risk group. In conclusion, this simple risk prediction model consisting of age, urinary albumin-creatinine ratio, and clinical CVD history successfully identified a subset of hypertensive patients who derived a more favorable risk-benefit profile for intensive BP lowering., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Introduction: Despite a proposed connection between neighborhood environment and obesity, few longitudinal studies have examined the relationship between change in neighborhood socioeconomic deprivation, as defined by moving between neighborhoods, and change in body weight. The purpose of this study is to examine the longitudinal relationship between moving to more socioeconomically deprived neighborhoods and weight gain as a cardiovascular risk factor., Methods: Weight (kilograms) was measured in the Dallas Heart Study (DHS), a multiethnic cohort aged 18-65 years, at baseline (2000-2002) and 7-year follow-up (2007-2009, N=1,835). Data were analyzed in 2013-2014. Geocoded addresses were linked to Dallas County, TX, census block groups. A block group-level neighborhood deprivation index (NDI) was created. Multilevel difference-in-difference models with random effects and a Heckman correction factor (HCF) determined weight change relative to NDI change., Results: Forty-nine percent of the DHS population moved (263 to higher NDI, 586 to lower NDI, 47 within same NDI), with blacks more likely to move than whites or Hispanics (p<0.01), but similar baseline BMI and waist circumference were observed in movers versus non-movers (p>0.05). Adjusting for HCF, sex, race, and time-varying covariates, those who moved to areas of higher NDI gained more weight compared to those remaining in the same or moving to a lower NDI (0.64 kg per 1-unit NDI increase, 95% CI=0.09, 1.19). Impact of NDI change on weight gain increased with time (p=0.03)., Conclusions: Moving to more-socioeconomically deprived neighborhoods was associated with weight gain among DHS participants., (Published by Elsevier Inc.)

Therapies targeting high-density lipoprotein cholesterol content (HDL-C) have not improved coronary heart disease (CHD) outcomes. High-density lipoprotein particle concentration (HDL-P) may better predict CHD. However, the impact of race/ethnicity on the relations between HDL-P and subclinical atherosclerosis and incident CHD events has not been described. Participants from the Dallas Heart Study (DHS), a multiethnic, probability-based, population cohort of Dallas County adults, underwent the following baseline measurements: HDL-C, HDL-P by nuclear magnetic resonance imaging, and coronary artery calcium by electron-beam computed tomography. Participants were followed for a median of 9.3 years for incident CHD events (composite of first myocardial infarction, stroke, coronary revascularization, or cardiovascular death). The study comprised 1,977 participants free of CHD (51% women, 46% black). In adjusted models, HDL-C was not associated with prevalent coronary artery calcium (p = 0.13) or incident CHD overall (hazard ratio [HR] per 1 SD 0.89, 95% confidence interval [CI] 0.76 to 1.05). However, HDL-C was inversely associated with incident CHD among nonblack (adjusted HR per 1 SD 0.67, 95% CI 0.46 to 0.97) but not black participants (HR 0.94, 95% CI 0.78 to 1.13, pinteraction = 0.05). Conversely, HDL-P, adjusted for risk factors and HDL-C, was inversely associated with prevalent coronary artery calcium (p = 0.009) and with incident CHD overall (adjusted HR per 1 SD 0.73, 95% CI 0.62 to 0.86), with no interaction by black race/ethnicity (pinteraction = 0.57). In conclusion, in contrast to HDL-C, the inverse relation between HDL-P and incident CHD events is consistent across ethnicities. These findings suggest that HDL-P is superior to HDL-C in predicting prevalent atherosclerosis as well as incident CHD events across a diverse population and should be considered as a therapeutic target., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: The absence of coronary artery calcium (CAC) in middle age is associated with very low short-term risk for coronary events. However, the long-term implications of a CAC score of 0 are uncertain, particularly among individuals with high cardiovascular lifetime risk. We sought to characterize the association between predicted lifetime risk and incident CAC among individuals with low short-term risk., Methods and Results: We included 754 Dallas Heart Study participants with serial CAC scans (6.9 years apart) and both low short-term risk and baseline CAC=0. Lifetime risk for cardiovascular disease was estimated according to risk factor burden. Among this group, 365 individuals (48.4%) were at low lifetime risk and 389 (51.6%) at high lifetime risk. High lifetime risk was associated with higher annualized CAC incidence (4.2% versus 2.7%; P < 0.001). Similarly, mean follow-up CAC scores were higher among participants with high lifetime risk (7.8 versus 2.4 Agatston units). After adjustment for age, sex, and race, high lifetime risk remained independently associated with incident CAC (OR 1.60; 95% CI 1.12 to 2.27; P=0.01). When assessing risk factor burden at the follow-up visit, 66.7% of CAC incidence observed in the low lifetime risk group occurred among individuals reclassified to a higher short- or long-term risk category., Conclusion: Among individuals with low short-term risk and CAC scores of 0, high lifetime risk is associated with a higher incidence of CAC. These findings highlight the importance of lifetime risk even among individuals with very low short-term risk., (© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Background: Obesity has been linked to the development of hypertension, but whether total adiposity or site-specific fat accumulation underpins this relationship is unclear., Objectives: This study sought to determine the relationship between adipose tissue distribution and incident hypertension., Methods: Normotensive participants enrolled in the Dallas Heart Study were followed for a median of 7 years for the development of hypertension (systolic blood pressure [SBP] ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or initiation of blood pressure medications). Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) was quantified by magnetic resonance imaging and proton-spectroscopic imaging, and lower body fat (LBF) was imaged by dual-energy x-ray absorptiometry. Multivariable relative risk regression was performed to test the association between individual fat depots and incident hypertension, adjusting for age, sex, race/ethnicity, diabetes, smoking, SBP, and body mass index (BMI)., Results: Among 903 participants (median age, 40 years; 57% women; 60% nonwhite; median BMI 27.5 kg/m(2)), 230 (25%) developed incident hypertension. In multivariable analyses, higher BMI was significantly associated with incident hypertension (relative risk: 1.24; 95% confidence interval: 1.12 to 1.36, per 1-SD increase). However, when VAT, SAT, and LBF were added to the model, only VAT remained independently associated with incident hypertension (relative risk: 1.22; 95% confidence interval: 1.06 to 1.39, per 1-SD increase)., Conclusions: Increased visceral adiposity, but not total or subcutaneous adiposity, was robustly associated with incident hypertension. Additional studies will be needed to elucidate the mechanisms behind this association., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study is to examine a relationship between neighborhood-level socioeconomic deprivation and weight change in a multi-ethnic cohort from Dallas County, Texas and whether behavioral/psychosocial factors attenuate the relationship., Methods: Non-movers (those in the same neighborhood throughout the study period) aged 18-65 (N=939) in Dallas Heart Study (DHS) underwent weight measurements between 2000 and 2009 (median 7-year follow-up). Geocoded home addresses defined block groups; a neighborhood deprivation index (NDI) was created (higher NDI=greater deprivation). Multi-level modeling determined weight change relative to NDI. Model fit improvement was examined with adding physical activity and neighborhood environment perceptions (higher score=more unfavorable perceptions) as covariates. A significant interaction between residence length and NDI was found (p-interaction=0.04); results were stratified by median residence length (11 years)., Results: Adjusting for age, sex, race/ethnicity, smoking, and education/income, those who lived in neighborhood >11 years gained 1.0 kg per one-unit increment of NDI (p=0.03), or 6 kg for those in highest NDI tertile compared with those in the lowest tertile. Physical activity improved model fit; NDI remained associated with weight gain after adjustment for physical activity and neighborhood environment perceptions. There was no significant relationship between NDI and weight change for those in their neighborhood ≤11 years., Conclusions: Living in more socioeconomically deprived neighborhoods over a longer time period was associated with weight gain in DHS., (Published by Elsevier Inc.)

Objectives: Although psychosocial stress can result in adverse health outcomes, little is known about how perceptions of neighborhood conditions, a measure of environment-derived stress, may impact obesity. The association between perceptions of neighborhood environment and obesity (defined as body mass index [BMI] ≥ 30 kg/m(2) ) among 5,907 participants in the Dallas Heart Study, a multi-ethnic, probability-based sample of Dallas County residents was examined., Design and Methods: Participants were asked to respond to 18 questions about perceptions of their neighborhood. Factor analysis was used to identify three factors associated with neighborhood perceptions: neighborhood violence, physical environment, and social cohesion. Logistic regression analyses were performed to determine the relationship between each factor (higher quintile = more unfavorable perceptions) and the odds of obesity., Results: Decreasing age, income, and education associated with unfavorable overall neighborhood perceptions and unfavorable perceptions about specific neighborhood factors (P trend <0.05 for all). Increasing BMI was associated with unfavorable perceptions about physical environment (P trend <0.05) but not violence or social cohesion. After adjustment for race, age, sex, income, education, and length of residence, physical environment perception score in the highest quintile remained associated with a 25% greater odds of obesity (OR 1.25, [95% CI 1.03-1.50]). Predictors of obesity related to environmental perceptions included heavy traffic (OR 1.39, [1.17-1.64]), trash/litter in neighborhood (OR 1.27, [1.01-1.46]), lack of recreational areas (OR 1.21, [1.01-1.46]), and lack of sidewalks (OR 1.25, [95% CI 1.04-1.51])., Conclusions: Thus, unfavorable perceptions of environmental physical conditions are related to increased obesity. Efforts to improve the physical characteristics of neighborhoods, or the perceptions of those characteristics, may assist in the prevention of obesity in this community., (Copyright © 2012 The Obesity Society.)

Context: Previous small case-control studies have suggested an inverse relationship between adiponectin and hepatic steatosis, but whether this finding is independent of insulin sensitivity and other intraabdominal fat depots is unclear. OBJECTIVES AND MAIN OUTCOME MEASURES: The objective of this study was to establish whether an independent relationship exists between serum adiponectin concentrations and liver fat., Design, Setting, and Patients: Adiponectin levels were compared with hepatic triglyceride content (HTGC) as assessed by proton magnetic resonance spectroscopy in 2215 participants from the Dallas Heart Study. Multivariate modeling was performed to control for the effects of intraabdominal fat, insulin sensitivity, and other baseline factors., Results: In unadjusted analysis, adiponectin levels displayed inverse correlations with the amount of intraabdominal fat and HTGC. After multivariate adjustment, including individual intraabdominal fat depots and homeostasis model assessment of insulin resistance, HTGC remained significantly associated with adiponectin levels (β = -1.46, P < 0.0001 for women; β = -1.81, P < 0.0001 for men). Race- and gender-specific models demonstrated that this association was consistent across groups, except for Hispanic men. The adjusted odds ratio for hepatic steatosis (HTGC > 5.5%) per 1-sd increase in adiponectin concentrations was 0.64 (95% confidence interval = 0.52-0.78) for women and 0.61 (95% confidence interval = 0.51-0.74) for men., Conclusion: Data from a large, multiethnic population-based cohort show adiponectin levels are inversely associated with hepatic steatosis even after controlling for measures of insulin sensitivity, extrahepatic abdominal adiposity, and ethnicity. The mechanistic underpinnings of this association warrant further exploration.

Background: Growth differentiation factor 15 (GDF-15) is produced by cardiomyocytes and atherosclerotic lesions under stress conditions. Although higher circulating GDF-15 concentrations are associated with mortality across a spectrum of cardiovascular conditions, the relationship of GDF-15 with atherosclerosis and mortality in the general population remains undefined., Methods: We measured plasma GDF-15 in 3219 participants of the Dallas Heart Study, a population sample of adults ages 30-65 years (55% women, 49% black). GDF-15 was analyzed in prespecified categories (<1200; 1200-1799; and ≥1800 ng/L) and continuously. End points included prevalent coronary artery calcium (CAC>10 Agatston units), increased CAC (CAC≥100 Agatston units) by electron beam computed tomography, and mortality through a median 7.3 years of follow-up (120 deaths, 48 cardiovascular deaths)., Results: Increasing GDF-15 associated with older age, black race, hypertension, diabetes, smoking, left ventricular (LV) mass/body surface area, and worse renal function (P<0.0001 for each). In multivariable models adjusted for traditional risk factors, renal function, and LV mass/body surface area, GDF-15≥1800 ng/L was associated with CAC>10 (odds ratio 2.1; 95% CI 1.2-3.7; P=0.01), CAC≥100 (odds ratio 2.6; 95% CI 1.4-4.9; P=0.002), all-cause mortality (hazard ratio 3.5; 95% CI 2.1-5.9, P<0.0001), and cardiovascular mortality (hazard ratio 2.5; 95% CI 1.1-5.8, P=0.03). Adding log GDF-15 to fully adjusted models modestly improved the c statistic (P=0.025), the integrated discrimination index (0.028; P<0.0001) and the category-less net reclassification index (0.42; P=0.002). These findings remained significant with further adjustment for high-sensitivity C-reactive protein, N-terminal pro-B-type natriuretic peptide, and cardiac troponin T., Conclusions: GDF-15 is independently associated with subclinical coronary atherosclerosis and mortality, and its potential role for risk stratification in the general population merits further evaluation.

Objective: Myeloperoxidase (MPO) is a leukocyte-derived enzyme that appears to be directly involved in atherosclerosis development. We evaluated the association of circulating MPO with coronary and aortic atherosclerosis in a large, multiethnic population., Methods and Results: Plasma levels of MPO were measured in 3294 subjects participating in the Dallas Heart Study, a probability-based population sample. Coronary artery calcification (CAC) was measured by EBCT, and abdominal aorta plaque prevalence (AP) and burden (APB), as well as abdominal aorta wall thickness (AWT) were determined by MRI. Associations between MPO and atherosclerosis phenotypes were assessed in multivariable analyses adjusting for traditional atherosclerosis risk factors. MPO levels in the 4th compared with 1st quartile independently associated with prevalent AP (OR 1.41, 95% CI 1.08-1.84), APB (beta coefficient 0.23, p = 0.02), and AWT (beta coefficient 0.04, p = 0.03), but not with prevalent CAC (OR 0.84, 95% CI 0.61-1.17). MPO remained associated with aortic atherosclerosis phenotypes but not coronary calcification after adjustment for other inflammatory biomarkers. A significant interaction was observed between race/ethnicity, MPO and AP (p(interaction) = 0.038), such that MPO levels in the 4th vs 1st quartile associated with prevalent AP in African Americans, (OR 1.81, 95% CI 1.23-2.65) but not in White or Hispanic participants (OR 0.99, 95% CI 0.68-1.44)., Conclusion: Higher levels of MPO associated with aortic but not coronary atherosclerosis, with significant associations limited to African American participants. These findings suggest that MPO might be a novel risk factor contributing to racial disparities in peripheral vascular disease., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Context: Detectable levels of cardiac troponin T (cTnT) are strongly associated with structural heart disease and increased risk of death and adverse cardiovascular events; however, cTnT is rarely detectable in the general population using standard assays., Objectives: To determine the prevalence and determinants of detectable cTnT in the population using a new highly sensitive assay and to assess whether cTnT levels measured with the new assay associate with pathological cardiac phenotypes and subsequent mortality., Design, Setting, and Participants: Cardiac troponin T levels were measured using both the standard and the highly sensitive assays in 3546 individuals aged 30 to 65 years enrolled between 2000 and 2002 in the Dallas Heart Study, a multiethnic, population-based cohort study. Mortality follow-up was complete through 2007. Participants were placed into 5 categories based on cTnT levels., Main Outcome Measures: Magnetic resonance imaging measurements of cardiac structure and function and mortality through a median of 6.4 (interquartile range, 6.0-6.8) years of follow-up., Results: In Dallas County, the prevalence of detectable cTnT (≥0.003 ng/mL) was 25.0% (95% confidence interval [CI], 22.7%-27.4%) with the highly sensitive assay vs 0.7% (95% CI, 0.3%-1.1%) with the standard assay. Prevalence was 37.1% (95% CI, 33.3%-41.0%) in men vs 12.9% (95% CI, 10.6%-15.2%) in women and 14.0% (95% CI, 11.2%-16.9%) in participants younger than 40 years vs 57.6% (95% CI, 47.0%-68.2%) in those 60 years and older. Prevalence of left ventricular hypertrophy increased from 7.5% (95% CI, 6.4%-8.8%) in the lowest cTnT category (<0.003 ng/mL) to 48.1% (95% CI, 36.7%-59.6%) in the highest (≥0.014 ng/mL) (P < .001); prevalence of left ventricular systolic dysfunction and chronic kidney disease also increased across categories (P < .001 for each). During a median follow-up of 6.4 years, there were 151 total deaths, including 62 cardiovascular disease deaths. All-cause mortality increased from 1.9% (95% CI, 1.5%-2.6%) to 28.4% (95% CI, 21.0%-37.8%) across higher cTnT categories (P < .001). After adjustment for traditional risk factors, C-reactive protein level, chronic kidney disease, and N-terminal pro-brain-type natriuretic peptide level, cTnT category remained independently associated with all-cause mortality (adjusted hazard ratio, 2.8 [95% CI, 1.4-5.2] in the highest category). Adding cTnT categories to the fully adjusted mortality model modestly improved model fit (P = .02) and the integrated discrimination index (0.010 [95% CI, 0.002-0.018]; P = .01)., Conclusion: In this population-based cohort, cTnT detected with a highly sensitive assay was associated with structural heart disease and subsequent risk for all-cause mortality.

Background: Identification of individuals in the community with left ventricular systolic dysfunction (LVSD) or left ventricular hypertrophy (LVH) may allow earlier initiation of disease-modifying treatment. We performed a comprehensive evaluation of the screening performance of B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) for LVSD or LVH., Methods: In 2,429 subjects without a history of heart failure, myocardial infarction, valvular abnormalities, or a serum creatinine >2.0 mg/dL enrolled in the Dallas Heart Study, measurement of BNP and NT-proBNP and cardiovascular magnetic resonance imaging were performed., Results: B-type natriuretic peptide and NT-proBNP were robustly associated with magnetic resonance imaging-defined LVH and LVSD (ejection fraction <55%) among men and women (P < .0001 for each). In the overall population, neither test discriminated well for LVH or LVSD (area under the receiver operating characteristic curve [AUROC] <0.7). Among women, no differences in AUROC were observed between BNP and NT-proBNP. Among men, AUROCs were similar between BNP and NT-proBNP in the overall population, but among subgroups age 50 or older, or with hypertension, the AUROCs for NT-proBNP (0.73-0.79) were higher than for BNP (0.63-0.69, P < .05 for each comparison). Compared with subjects with isolated BNP elevation (>97.5th percentile), those with isolated NT-proBNP elevation had worse renal function and more LVH and coronary calcium (P < .05 for each)., Conclusions: Overall, neither BNP nor NT-proBNP accurately discriminated subjects with LVH or LVSD in this predominately young and healthy population-based cohort. However, among high-risk men, NT-proBNP performed slightly better than BNP and comparably with other routinely used screening tests such as prostate-specific antigen measurement for prostate cancer.

Background: Timely reperfusion in ST-segment elevation myocardial infarction (STEMI) patients improves clinical outcomes. Implementing strategies to target institutional-specific delays are crucial for improved patient care., Methods and Results: Using a novel strategy to analyze specific components of door-to-balloon time (DBT) at our institution, we previously identified several specific interval delays in our prior STEMI protocol. We then implemented 4 strategies to reduce DBT: (1) emergency department physician activation of the STEMI protocol; (2) "single call" broadcast paging of the STEMI team by the page operator; (3) immediate feedback to the emergency and cardiology departments with joint monthly quality improvement meetings; and (4) transfer of the off-hours STEMI patient directly to the laboratory on activation by an in-hospital team. After implementation of the new protocol, we examined each component time interval from the first 59 consecutive STEMI patients treated with the new protocol between March 2007 and June 2008 and compared time intervals with the previous 184 STEMI patients. Compared with the previous 184 STEMI patients, the median DBT of the subsequent 59 STEMI patients significantly improved from 125 to 86 minutes (P<0.0001). This improvement was largely driven by a decrease in the interval from the initial 12-lead ECG to activation of the on-call catheterization team (from 40 to 11 minutes, P<0.0001)., Conclusions: After examining specific component delays in our institution's DBT, we were able to successfully use quality improvement strategies to focus on specific sources of delay in our institution. This dramatically improved our median DBT toward the goal of achieving a guideline-recommended <90 minutes for all patients.

Background: Caspase-3, an apoptosis protease, is expressed in atherosclerotic plaques. We examined the relationship between plasma caspase-3 levels, aortic compliance, and atherosclerosis., Methods: Caspase-3 was measured in 3,221 subjects from the Dallas Heart Study. Electron beam computed tomography measures of coronary calcium (CAC) (n = 2,404) and magnetic resonance imaging (MRI) measures of abdominal aortic wall thickness (AWT) (n = 2,208) and aortic compliance (AC) (n = 2,328) were obtained. Multivariate analyses were performed, adjusting for age, sex, ethnicity, body mass index (BMI), traditional cardiovascular risk factors, and cardiac medications., Results: In univariable analysis, caspase-3 associated with CAC (P < 0.0001), AWT (P = 0.002), and AC (P < 0.0001). After multivariable adjustment, 4th quartile caspase-3 (compared to 1st quartile) was significantly associated with CAC (P = 0.004), AWT (P = 0.02), and AC (P < 0.0001) with similar findings for caspase-3 as a continuous variable., Conclusions: Caspase-3 independently associates with CAC, AWT, and AC, suggesting a link between apoptosis and atherosclerosis.

Background: Diabetes mellitus is a major public health problem in the United States. We assess the prevalence of diabetes in Dallas County, quantify the association between diabetes and subclinical cardiovascular disease, and assess the use of evidence-based cardiovascular disease risk-modifying therapies., Methods: This study uses data from 3392 participants aged 30 to 65 years from the Dallas Heart Study, a probability-based, multiethnic sample of residents living in Dallas County, Texas. Three primary outcomes were examined: (1) diabetes prevalence, (2) adjusted odds ratios for detectable coronary calcium stratified by diabetes diagnosis status, and (3) rates of use of evidence-based cardiovascular disease risk-modifying therapies among subjects with diabetes stratified by diabetes diagnosis status., Results: The estimated prevalence of diabetes in Dallas County was 7.8%, with >40% of diabetic patients undiagnosed before participation in the Dallas Heart Study. Both previously diagnosed and previously undiagnosed diabetes were independently associated with the presence of coronary artery calcium (diagnosed: OR 3.55, 95% CI 1.56-8.05) (undiagnosed: OR 2.98, 95% CI 1.39-6.39). The rates of use of aspirin, angiotensin-converting enzyme inhibitors, and statins were suboptimal, and blood pressure and low-density lipoprotein cholesterol targets were rarely met, especially among subjects with previously undiagnosed diabetes., Conclusions: Diabetes is prevalent and is associated with subclinical cardiovascular disease; this association is present even at the time of diagnosis. Despite the cardiovascular risk associated with diabetes, evidence-based risk-modifying therapies continue to be underused, and therapeutic targets remain unmet, especially among people unaware of their diabetes diagnosis.

Background: Although gender-specific criteria are common for defining cardiac traits such as left ventricular hypertrophy, left ventricular ejection fraction (LVEF) thresholds widely used in clinical practice have traditionally been the same for women and men, perhaps because it remains uncertain whether there is a systematic difference in LVEF between genders., Methods and Results: Using cardiac magnetic resonance imaging in a probability-based sample of Dallas County residents aged 30 to 65 years (1435 women and 1183 men), we compared LVEF in women and men. The association of gender with stroke volume independent of end-diastolic volume (EDV) or other potential confounders was assessed by multivariable analysis. Gender-specific thresholds for a low LVEF were defined at the 2.5th percentile in women and men from a healthy reference subpopulation. The median (25th, 75th percentile) LVEF was higher in women than in men (75% [70%, 79%] in women versus 70% [65%, 75%] in men, P<0.001). Left ventricular EDV and end-systolic volume indexed to body surface area were smaller in women than in men (P<0.001 for both). Gender remained significantly associated with stroke volume, independent of EDV and other potential confounders in multivariable analysis. A low LVEF was defined as below 61% in women and below 55% in men., Conclusions: Women have a higher LVEF than men in the general population, secondary to a higher stroke volume for a given EDV independent of known potential confounders.

Background: The association between higher body mass index (BMI) and lower B-type natriuretic peptide (BNP) level is thought to be mediated by expression of the natriuretic peptide clearance receptor (NPR-C) in adipose tissue. To explore this association, we tested 2 hypotheses: (1) that N-terminal (NT)-proBNP, which is not believed to bind NPR-C, would not be associated with BMI and (2) that lower BNP would be more closely associated with fat mass than with lean mass., Methods and Results: Measurements of BNP, NT-proBNP, and body composition by direct dual energy x-ray absorptiometry (DEXA) were performed in 2707 subjects from the Dallas Heart Study. The associations between obesity and low BNP (<4 ng/L) or low NT-proBNP (lowest sex-specific quartile) were evaluated with multivariable logistic regression models stratified by sex and adjusted for age, race/ethnicity, hypertension, left ventricular mass, and end-diastolic volume. Higher BMI was independently associated with lower BNP and NT-proBNP (all P<0.001). When BMI was replaced with both DEXA-derived lean and fat mass, greater lean mass, but not fat mass, was associated with low BNP and NT-proBNP levels., Conclusions: In a large, population-based cohort, we confirm the previously described association between higher BMI and lower BNP and demonstrate a similar inverse association between BMI and NT-proBNP. Interestingly, both BNP and NT-proBNP are more closely associated with lean mass than with fat mass. These findings do not support the hypothesis that the lower BNP levels seen in obesity are driven by enhanced BNP clearance mediated via NPR-C.