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Background: Diabetes is associated with abnormalities in cardiac remodeling and high risk of heart failure (HF).Objectives: The purpose of this study was to evaluate the prevalence and prognostic implications of diabetes with cardiomyopathy (DbCM) among community-dwelling individuals.Methods: Adults without prevalent cardiovascular disease or HF were pooled from 3 cohort studies (ARIC [Atherosclerosis Risk In Communities], CHS [Cardiovascular Health Study], CRIC [Chronic Renal Insufficiency Cohort]). Among participants with diabetes, DbCM was defined using different definitions: 1) least restrictive: ≥1 echocardiographic abnormality (left atrial enlargement, left ventricle hypertrophy, diastolic dysfunction); 2) intermediate restrictive: ≥2 echocardiographic abnormalities; and 3) most restrictive: elevated N-terminal pro-B-type natriuretic peptide levels (>125 in normal/overweight or >100 pg/mL in obese) plus ≥2 echocardiographic abnormalities. Adjusted Fine-Gray models were used to evaluate the risk of HF.Results: Among individuals with diabetes (2,900 of 10,208 included), the prevalence of DbCM ranged from 67.0% to 11.7% in the least and most restrictive criteria, respectively. Higher fasting glucose, body mass index, and age as well as worse kidney function were associated with higher risk of DbCM. The 5-year incidence of HF among participants with DbCM ranged from 8.4%-12.8% in the least and most restrictive definitions, respectively. Compared with euglycemia, DbCM was significantly associated with higher risk of incident HF with the highest risk observed for the most restrictive definition of DbCM (HR: 2.55 [95% CI: 1.69-3.86]; least restrictive criteria HR: 1.99 [95% CI: 1.50-2.65]). A similar pattern of results was observed across cohort studies, across sex and race subgroups, and among participants without hypertension or obesity.Conclusions: Regardless of the criteria used to define cardiomyopathy, DbCM identifies a high-risk subgroup for developing HF. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objectives: The goal of this study was to investigate the association between natriuretic peptides and body fat distribution in a multiethnic cohort. Background: Natriuretic peptides stimulate lipolysis, reduce weight gain, and promote adipocyte browning in animal models, but data are lacking in humans. Methods: A total of 2,619 participants without heart failure in the Dallas Heart Study underwent measurements of 1) B-type natriuretic peptide (BNP) and N-terminal pro–B-type natriuretic peptide (NT-proBNP); and 2) body fat distribution by dual energy x-ray absorptiometry and magnetic resonance imaging. Cross-sectional associations of natriuretic peptides with adiposity phenotypes were examined after adjustment for age, sex, race, comorbidities, and body mass index. Results: Median BNP and NT-proBNP levels in the study cohort (mean age 44 years; 56% women, 48% African Americans, 32% obese) were 3.0 and 28.1 pg/ml, respectively. Natriuretic peptide levels above the median were associated with a more favorable body fat profile and less insulin resistance, including lower visceral fat, liver fat, and homeostasis model assessment of insulin resistance index, and increased lower body fat and higher adiponectin (p < 0.05 for each). In multivariable analyses, NT-proBNP remained inversely associated with visceral fat (beta coefficient = −0.08; p < 0.0001) and liver fat (beta coefficient = −0.14; p < 0.0001) and positively associated with lower body fat (beta coefficient = 0.07; p < 0.0001) independent of age, sex, race, and obesity status; findings were similar with BNP. Adjustment for body composition, homeostasis model assessment of insulin resistance index, circulating androgens, and adipocytokines did not attenuate the associations. Conclusions: Higher natriuretic peptide levels were independently associated with a favorable adiposity profile, characterized by decreased visceral and liver fat and increased lower body fat, suggesting a link between the heart and adipose tissue distribution mediated through natriuretic peptides. [Copyright &y& Elsevier]

Women with angina pectoris and abnormal stress test findings commonly have no epicardial coronary artery disease (CAD) at catheterization. The aim of the present study was to develop a risk score to predict obstructive CAD in such patients. Data were analyzed from 337 consecutive women with angina pectoris and abnormal stress test findings who underwent cardiac catheterization at our center from 2003 to 2007. Forward selection multivariate logistic regression analysis was used to identify the independent predictors of CAD, defined by ‡50% diameter stenosis in ‡1 epicardial coronary artery. The independent predictors included age ‡55 years (odds ratio 2.3, 95% confidence interval 1.3 to 4.0), body mass index <30 kg/m2 (odds ratio 1.9, 95% confidence interval 1.1 to 3.1), smoking (odds ratio 2.6, 95% confidence interval 1.4 to 4.8), low high-density lipoprotein cholesterol (odds ratio 2.9, 95% confidence interval 1.5 to 5.5), family history of premature CAD (odds ratio 2.4, 95% confidence interval 1.0 to 5.7), lateral abnormality on stress imaging (odds ratio 2.8, 95% confidence interval 1.5 to 5.5), and exercise capacity <5 metabolic equivalents (odds ratio 2.4, 95% confidence interval 1.1 to 5.6). Assigning each variable 1 point summed to constitute a risk score, a graded association between the score and prevalent CAD (ptrend <0.001). The risk score demonstrated good discrimination with a cross-validated c-statistic of 0.745 (95% confidence interval 0.70 to 0.79), and an optimized cutpoint of a score of £2 included 62% of the subjects and had a negative predictive value of 80%. In conclusion, a simple clinical risk score of 7 characteristics can help differentiate those more or less likely to have CAD among women with angina pectoris and abnormal stress test findings. This tool, if validated, could help to guide testing strategies in women with angina pectoris. [ABSTRACT FROM AUTHOR]

Objectives: This study sought to evaluate whether the relationship between C-reactive protein (CRP) and atherosclerosis is modified by body mass index (BMI). Background: CRP levels are affected by obesity, and it is unknown whether the associations between CRP and cardiovascular (CV) disease differ between obese and nonobese individuals. Methods: We measured CRP and multiple atherosclerosis phenotypes, including coronary artery calcification (CAC) (n = 2,685), aortic wall thickness (AWT) (n = 2,238), and aortic plaque burden (APB) (n = 2,224), in subjects ages 30 to 65 years from the Dallas Heart Study. The associations of CRP with CAC, AWT, and APB were compared across categories of BMI (normal, 18.5 to <25 kg/m2; overweight, 25 to <30 kg/m2; obese, ≥30 kg/m2) in sex-stratified analyses. Results: The overall prevalence of obesity was 38% in men and 53% in women. Increasing CRP levels (<1 mg/l, 1 to 3 mg/l, >3 mg/l) were associated with increased CAC prevalence in normal and overweight men and in normal weight women (p < 0.01), but not in obese subjects of either sex. Likewise, the correlations between CRP and AWT and APB diminished with increasing BMI and were nonsignificant in obese individuals (p < 0.05 in nonobese, p > 0.1 in obese). Interaction tests between CRP and obesity were significant for all atherosclerosis measures in men and for AWT and ABP in women (p interaction <0.05 each). In both sexes, the c-statistics of CRP for all 3 atherosclerosis measures were greater for normal weight than obese individuals. Conclusions: In a large, population-based study, the association between CRP and multiple measures of atherosclerosis is diminished in obese individuals. The role of CRP for predicting CV outcomes in obese subjects requires further evaluation. [ABSTRACT FROM AUTHOR]

The Fick principle (cardiac output [Qc] = oxygen uptake [Vo 2]/arteriovenous oxygen difference) can be used to calculate Qc, with VO2 frequently estimated by derived equations. To compare the accuracy of measured versus estimated VO2, data were analyzed from 2 studies in which VO2 at rest was measured using the Douglas bag technique. One study comprised adults with diabetes, and the other was an exercise study of healthy adults. VO2 at rest was estimated as VO2 (ml/min) = 125 ml/min/m2 × body surface area (m2), with sensitivity analyses evaluating 2 other commonly used equations. Mean absolute difference (milliliters per minute) and ordinary least products regression were used to assess agreement between measured and estimated VO2. Overall, mean measured versus estimated VO2 differed significantly (307.2 ± 75.2 vs 259.9 ± 36.7 ml/min, p <0.0001), with a mean absolute difference of 52.9 ± 43.2 ml/min (p <0.0001); 20% of the estimates differed by >25% from the measured VO2. Mean absolute difference increased from 36.7 ml/min in the lowest body mass index group (<25 kg/m2) to 91.7 ml/min in the highest group (≥40 kg/m2) (p for trend = 0.001) and was significantly higher in men than in women (65.6 vs 33.9 ml/min, p = 0.001); error was similar by median-split age (p = 0.65) and race (p = 0.34). Similar results were obtained when evaluating each of the other 2 estimating equations. Estimation of VO2 at rest is inaccurate, especially in men and with increasing adiposity. In conclusion, when clinical hemodynamic assessment is performed, VO2 should be measured, not estimated. [ABSTRACT FROM AUTHOR]