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The associations of pulmonary function with cardiovascular disease (CVD) independent of diabetes mellitus (DM) and metabolic syndrome have not been examined in a populationbased setting. We examined prevalence and incidence CVD in relation to lower pulmonary function in the Strong Heart Study second examination (1993 to 1995) in 352 CVD and 2,873 non-CVD adults free of overt lung disease (mean age 60 years). Lung function was assessed by standard spirometry. Participants with metabolic syndrome or DM with or without CVD had lower pulmonary function than participants without these conditions after adjustment for hypertension, age, gender, abdominal obesity, smoking, physical activity index, and study field center. CVD participants with DM had significantly lower forced vital capacity than participants with CVD alone. Significant associations were observed between reduced pulmonary function, preclinical CVD, and prevalent CVD after adjustment for multiple CVD risk factors. During follow-up (median 13.3 years), pulmonary function did not predict CVD incidence, it predicted CVD mortality. Among 3,225 participants, 412 (298 without baseline CVD) died from CVD by the end of 2008. In models adjusted for multiple CVD risk factors, DM, metabolic syndrome, and baseline CVD, compared with highest quartile of lung function, lower lung function predicted CVD mortality (relative risk up to 1.5, 95% confidence interval 1.1 to 2.0, p <0.05). In conclusion, a population with a high prevalence of DM and metabolic syndrome and lower lung function was independently associated with prevalent clinical and preclinical CVD, and its impairment predicted CVD mortality. Additional research is needed to identify mechanisms linking metabolic abnormalities, low lung function, and CVD. [ABSTRACT FROM AUTHOR]

Nomograms to predict normal aortic root diameter for body surface area (BSA) in broad ranges of age have been widely used but are limited by lack of consideration of gender effects, jumps in upper limits of aortic diameter among age strata, and data from older teenagers. Sinus of Valsalva diameter was measured by American Society of Echocardiography convention in normal-weight, nonhypertensive, nondiabetic subjects ≥15 years old without aortic valve disease from clinical or population-based samples. Analyses of covariance and linear regression with assessment of residuals identified determinants and developed predictive models for normal aortic root diameter. In 1,207 apparently normal subjects ≥15 years old (54% women), aortic root diameter was 2.1 to 4.3 cm. Aortic root diameter was strongly related to BSA and height (r = 0.48 for the 2 comparisons), age (r = 0.36), and male gender (+2.7 mm adjusted for BSA and age, p <0.001 for all comparisons). Multivariable equations using age, gender, and BSA or height predicted aortic diameter strongly (R = 0.674 for the 2 comparisons, p <0.001) with minimal relation of residuals to age or body size: for BSA 2.423 + (age [years] × 0.009) + (BSA [square meters] × 0.461) - (gender [1 = man, 2 = woman] × 0.267), SEE 0.261 cm; for height 1.519 + (age [years] × 0.010) + (height [centimeters] × 0.010) - (gender [1 = man, 2 = woman] × 0.247), SEE 0.215 cm. In conclusion, aortic root diameter is larger in men and increases with body size and age. Regression models incorporating body size, age, and gender are applicable to adolescents and adults without limitations of previous nomograms. [ABSTRACT FROM AUTHOR]

Several biomarkers have been documented, singly or jointly, to improve risk prediction, but the extent to which they improve prediction-model performance in populations with high prevalences of obesity and diabetes has not been specifically examined. The aim of this study was to evaluate the ability of various biomarkers to improve prediction-model performance for death and major cardiovascular disease (CVD) events in a high-risk population. The relations of 6 biomarkers with outcomes were examined in 823 American Indians free of prevalent CVD or renal insufficiency, as were their contributions to risk prediction. In single-marker models adjusting for standard clinical and laboratory risk factors, 4 of 6 biomarkers significantly predicted mortality and major CVD events. In multimarker models, these 4 biomarkers—urinary albumin/creatinine ratio (UACR), glycosylated hemoglobin, B-type natriuretic peptide, and fibrinogen—significantly predicted mortality, while 2—UACR and fibrinogen—significantly predicted CVD. On the basis of its robust association in participants with diabetes, UACR was the strongest predictor of mortality and CVD, individually improving model discrimination or classification in the entire cohort. Singly, all remaining biomarkers also improved risk classification for mortality and enhanced average sensitivity for mortality and CVD. The addition of ≥1 biomarker to the single marker UACR further improved discrimination or average sensitivity for these outcomes. In conclusion, biomarkers derived from diabetic cohorts, and novel biomarkers evaluated primarily in lower risk populations, improve risk prediction in cohorts with prevalent obesity and diabetes. Risk stratification of these populations with multimarker models could enhance selection for aggressive medical or surgical approaches to prevention. [Copyright &y& Elsevier]

The qualitative electrocardiographic strain pattern of ST depression (STD) and T-wave inversion is strongly associated with coronary heart disease and left ventricular hypertrophy and is an independent predictor of new-onset heart failure in hypertensive participants. However, whether quantitative measures of STD in the lateral precordial leads predict new heart failure is unclear. Digital electrocardiograms were examined in 2,059 American-Indian participants in the second Strong Heart Study examination with no history of heart failure. The absolute magnitude of ST segment deviation was measured using computer to the nearest 5 μV in leads V5 and V6. During 5.7 ±̣1.4 years of follow-up, heart failure developed in 77 participants (3.7%). Participants who developed heart failure had greater STD in leads V5 or V6 (−11 ± 35 vs 12 ± 27 μV; p <0.001) than those who did not. In univariate Cox analyses, STD was a significant predictor of new heart failure, with each 10-μV greater STD associated with a 31% greater risk of heart failure (hazard ratio [HR] 1.31, 95% confidence interval [CI] 1.24 to 1.39). Increasing STD grouped according to quartiles was strongly associated with the development of heart failure, with stepwise increasing risk of heart failure compared with the lowest quartile of STD for the second (HR 2.39, 95% CI 0.77 to 7.40), third (HR 3.01, 95% CI 1.00 to 9.08), and fourth quartiles of STD (HR 9.06, 95% CI 3.26 to 25.16). In Cox multivariate analyses controlling for age, gender, diabetes, coronary heart disease, albuminuria, and other baseline risk factors, STD remained a significant predictor of incident heart failure (HR 1.22, 95% CI 1.13 to 1.32 per 10-μV increment in STD; p <0.001). In conclusion, increasing STD in lateral precordial leads is strongly associated with increased risk of developing heart failure independent of other risk factors for new heart failure. [Copyright &y& Elsevier]

Recognition of the frequency with which hypertrophic cardiomyopathy (HC) occurs in the general population is critical to understanding its demographics and public health implications. However, few data are available for estimating HC prevalence in large populations of different age strata and ethnic or racial groups. The Strong Heart Study is a prospective, population-based epidemiologic survey of cardiovascular disease in residents of 13 geographically diverse American Indian communities. The study population was comprised of 3,501 subjects with echocardiograms performed in 1993 and 1995 to determine the prevalence of HC in middle-aged and older adult populations. Evidence of the HC phenotype was present in 8 previously undiagnosed patients (0.23%; 2 of 1,000) based on a left ventricular (LV) wall thickness ≥15 mm and a nondilated cavity that was not associated with another cardiac disease and was sufficient to produce the magnitude of hypertrophy evident. Ages were 51 to 77 years (mean 64 ± 9). Four subjects were men and 4 were women, with prevalences by gender of 0.3% (3 of 1,000) and 0.18% (1.8 of 1,000), respectively. Maximum LV thicknesses were 19 to 29 mm (mean 21 ± 3). Two subjects had mitral valve systolic anterior motion, which was sufficient to produce LV outflow obstruction at rest in 1 patient. Different electrocardiographic abnormalities were present in 5 subjects. In conclusion, clinically unrecognized HC was present in 1:500 of an aging American Indian cohort. This prevalence was similar to that reported in other general populations comprised of younger subjects of other races, offering evidence that HC is a relatively common genetic disease with widespread occurrence within the United States. [Copyright &y& Elsevier]

The metabolic syndrome (MS) is linked to cardiovascular risk. Recently, the Adult Treatment Panel (ATP) III provided new criteria for the definition of the MS. We analyzed the impact of the MS on cardiac structure and function and the independent association of the 5 different components of the ATP III-defined MS with cardiac markers of preclinical disease. Echocardiographic examination was performed in 612 nondiabetic participants with ATP III-defined MS and in 824 participants without the MS. Participants with the MS were more often women (p <0.001) and had similar ages compared with those without the MS. After controlling for confounders, participants with the MS had greater left ventricular (LV) dimension, mass, and relative wall thickness, and left atrial diameter (all p ≤0.01), and a higher prevalence of LV hypertrophy (p <0.001), with lower ejection fraction (p <0.05), midwall shortening (p <0.001), and mitral E/A ratio (p <0.05) than participants who did not have the MS. In multiple regression modeling, high blood pressure (BP) and abdominal obesity were the only components of the MS associated with increased LV diameter; only high BP was associated with increased LV mass and prevalence of LV hypertrophy (both p <0.001). When high to normal BP was present in the absence of hypertension, the MS exhibited LV geometry similar to hypertensive participants without the MS. Therefore, abnormal LV geometry and function are related to the MS. Increased BP is the component of the MS most strongly associated with cardiac markers of preclinical disease, even in the absence of traditionally defined hypertension. [Copyright &y& Elsevier]

Electrocardiographic QRS duration at rest is associated with sudden cardiac death and death from coronary heart disease in the general population. However, its relation to cardiovascular events in American Indians, a population with persistently high cardiovascular disease mortality, is unknown. The relation of QRS duration to incident cardiovascular disease during 17.2 years of follow-up was assessed in 1,851 male and female Strong Heart Study participants aged 45 to 74 years without known cardiovascular disease at baseline. Cox regression with robust standard error estimates was used to determine the association between quintiles of QRS duration and incident cardiovascular disease in gender-stratified analyses, adjusted for age, systolic blood pressure, hypertension, antihypertensive medication use, body mass index, current smoking, diabetes, total cholesterol, high-density lipoprotein cholesterol, and albuminuria. In women only, QRS duration in the highest quintile (≥105 ms) conferred significantly higher risk of cardiovascular disease than QRS duration in the lowest quintile (64 to 84 ms) (hazard ratio 1.6, 95% CI 1.1 to 2.4) likely because of higher risks of coronary heart disease (hazard ratio 1.8, 95% CI 1.1 to 3.1) and myocardial infarction (hazard ratio 2.1, 95% CI 1.0 to 4.7). Furthermore, when added to the Strong Heart Study Coronary Heart Disease Risk Calculator, QRS duration significantly improved prediction of future coronary heart disease events in women (Net Reclassification Index 0.17, 95% CI 0.06 to 0.47). In conclusion, QRS duration is an independent predictor of cardiovascular disease in women in the Strong Heart Study cohort and may have value in estimating risk in populations with similar risk profiles and a high lifetime incidence of cardiovascular disease., (Copyright © 2017 Elsevier Inc. All rights reserved.)