Measurement error and reliability in four pediatric cross-sectional surveys of cardiovascular disease risk factor variables--the Bogalusa Heart Study

Associations of Epigenetic Age Acceleration With CVD Risks Across the Lifespan: The Bogalusa Heart Study

Although epigenetic age acceleration (EAA) might serve as a molecular signature of childhood cardiovascular disease (CVD) risk factors and further promote midlife subclinical CVD, few studies have comprehensively examined these life course associations. This study sought to test whether childhood CVD risk factors predict EAA in adulthood and whether EAA mediates the association between childhood CVD risks and midlife subclinical disease. Among 1,580 Bogalusa Heart Study participants, we estimated extrinsic EAA, intrinsic EAA, PhenoAge acceleration (PhenoAgeAccel), and GrimAge acceleration (GrimAgeAccel) during adulthood. We tested prospective associations of longitudinal childhood body mass index (BMI), blood pressure, lipids, and glucose with EAAs using linear mixed effects models. After confirming EAAs with midlife carotid intima-media thickness and carotid plaque, structural equation models examined mediating effects of EAAs on associations of childhood CVD risk factors with subclinical CVD measures. After stringent multiple testing corrections, each SD increase in childhood BMI was significantly associated with 0.6-, 0.9-, and 0.5-year increases in extrinsic EAA, PhenoAgeAccel, and GrimAgeAccel, respectively (P < 0.001 for all 3 associations). Likewise, each SD increase in childhood log-triglycerides was associated with 0.5- and 0.4-year increases in PhenoAgeAccel and GrimAgeAccel (P < 0.001 for both), respectively, whereas each SD increase in childhood high-density lipoprotein cholesterol was associated with a 0.3-year decrease in GrimAgeAccel (P = 0.002). Our findings indicate that PhenoAgeAccel mediates an estimated 27.4% of the association between childhood log-triglycerides and midlife carotid intima-media thickness (P = 0.022). Our data demonstrate that early life CVD risk factors may accelerate biological aging and promote subclinical atherosclerosis.

Brain effective connectivity and functional connectivity as markers of lifespan vascular exposures in middle-aged adults: The Bogalusa Heart Study

Introduction

Effective connectivity (EC), the causal influence that functional activity in a source brain location exerts over functional activity in a target brain location, has the potential to provide different information about brain network dynamics than functional connectivity (FC), which quantifies activity synchrony between locations. However, head-to-head comparisons between EC and FC from either task-based or resting-state functional MRI (fMRI) data are rare, especially in terms of how they associate with salient aspects of brain health.

Methods

In this study, 100 cognitively-healthy participants in the Bogalusa Heart Study aged 54.2 ± 4.3years completed Stroop task-based fMRI, resting-state fMRI. EC and FC among 24 regions of interest (ROIs) previously identified as involved in Stroop task execution (EC-task and FC-task) and among 33 default mode network ROIs (EC-rest and FC-rest) were calculated from task-based and resting-state fMRI using deep stacking networks and Pearson correlation. The EC and FC measures were thresholded to generate directed and undirected graphs, from which standard graph metrics were calculated. Linear regression models related graph metrics to demographic, cardiometabolic risk factors, and cognitive function measures.

Results

Women and whites (compared to men and African Americans) had better EC-task metrics, and better EC-task metrics associated with lower blood pressure, white matter hyperintensity volume, and higher vocabulary score (maximum value of p = 0.043). Women had better FC-task metrics, and better FC-task metrics associated with APOE-ε4 3–3 genotype and better hemoglobin-A1c, white matter hyperintensity volume and digit span backwards score (maximum value of p = 0.047). Better EC rest metrics associated with lower age, non-drinker status, and better BMI, white matter hyperintensity volume, logical memory II total score, and word reading score (maximum value of p = 0.044). Women and non-drinkers had better FC-rest metrics (value of p = 0.004).

Discussion

In a diverse, cognitively healthy, middle-aged community sample, EC and FC based graph metrics from task-based fMRI data, and EC based graph metrics from resting-state fMRI data, were associated with recognized indicators of brain health in differing ways. Future studies of brain health should consider taking both task-based and resting-state fMRI scans and measuring both EC and FC analyses to get a more complete picture of functional networks relevant to brain health.

Life-Course Associations between Blood Pressure-Related Polygenic Risk Scores and Hypertension in the Bogalusa Heart Study

Genetic information may help to identify individuals at increased risk for hypertension in early life, prior to the manifestation of elevated blood pressure (BP) values. We examined 369 Black and 832 White Bogalusa Heart Study (BHS) participants recruited in childhood and followed for approximately 37 years. The multi-ancestry genome-wide polygenic risk scores (PRSs) for systolic BP (SBP), diastolic BP (DBP), and hypertension were tested for an association with incident hypertension and stage 2 hypertension using Cox proportional hazards models. Race-stratified analyses were adjusted for baseline age, age2, sex, body mass index, genetic principal components, and BP. In Black participants, each standard deviation increase in SBP and DBP PRS conferred a 38% (p = 0.009) and 22% (p = 0.02) increased risk of hypertension and a 74% (p < 0.001) and 50% (p < 0.001) increased risk of stage 2 hypertension, respectively, while no association was observed with the hypertension PRSs. In Whites, each standard deviation increase in SBP, DBP, and hypertension PRS conferred a 24% (p < 0.05), 29% (p = 0.01), and 25% (p < 0.001) increased risk of hypertension, and a 27% (p = 0.08), 29% (0.01), and 42% (p < 0.001) increased risk of stage 2 hypertension, respectively. The addition of BP PRSs to the covariable-only models generally improved the C-statistics (p < 0.05). Multi-ancestry BP PRSs demonstrate the utility of genomic information in the early life prediction of hypertension.

Association of Genome-Wide Polygenic Risk Score for Body Mass Index With Cardiometabolic Health From Childhood Through Midlife

BACKGROUND

Genetic information may help to identify individuals in childhood who are at increased risk for cardiometabolic disease.

METHODS

We included 1201 BHS (Bogalusa Heart Study) participants (832 White participants and 369 Black participants) who were followed up to 42.3 years, starting at a mean age of 9.8 years. A validated genome-wide polygenic risk score (PRS) was tested for association with midlife body mass index (BMI), fasting plasma glucose, and systolic blood pressure using multiple linear regression models. Cox proportional hazards models tested associations of the PRS with incident obesity, diabetes, and hypertension. All analyses were conducted according to race and adjusted for baseline age, sex, ancestry, and BMI.

RESULTS

The constructed PRS was significantly and modestly correlated with midlife BMI in both White and Black participants, with correlation coefficients of 0.27 (P=1.94×10-8) and 0.16 (P=5.50×10-3), respectively. In White participants, per SD increase of PRS was associated with an average 1.29 kg/m2 higher BMI (P=4.44×10-9), 2.82 mg/dL higher fasting plasma glucose (P=1.17×10-3), and 1.09 mm Hg higher systolic blood pressure (P=3.57×10-2) at midlife. The PRS also conferred a 26% higher increased risk of obesity (P=3.50×10-6) in White participants. In addition, the variance in midlife BMI explained increased from 0.1973 to 0.2293 when PRS was added to the model including age, sex, principal components, and baseline BMI (P<0.0001). No associations were observed in Black participants.

CONCLUSIONS

Adiposity-related genetic information independently predicted cardiometabolic health in White BHS participants. Null associations observed in Black BHS participants highlight the urgent need for PRS development in multi-ancestry populations.

Metabolomics study of blood pressure salt-sensitivity and hypertension

BACKGROUND AND AIMS

Identify novel metabolite associations with blood pressure (BP) salt-sensitivity and hypertension.

METHODS AND RESULTS

The Genetic Epidemiology Network of Salt Sensitivity (GenSalt) Replication study includes 698 Chinese participants who underwent a 3-day baseline examination followed by a 7-day low-sodium feeding and 7-day high-sodium feeding. Latent mixture models identified three trajectories of blood pressure (BP) responses to the sodium interventions. We selected 50 most highly salt-sensitive and 50 most salt-resistant participants for untargeted metabolomics profiling. Multivariable adjusted mixed logistic regression models tested the associations of baseline metabolites with BP salt-sensitivity. Multivariable adjusted mixed linear regression models tested the associations of BP salt-sensitivity with metabolite changes during the sodium interventions. Identified metabolites were tested for associations with hypertension among 1249 Bogalusa Heart Study (BHS) participants using multiple logistic regression. Fifteen salt-sensitivity metabolites were associated with hypertension in the BHS. Baseline values of serine, 2-methylbutyrylcarnitine and isoleucine directly associated with high salt-sensitivity. Among them, serine indirectly associated with hypertension while 2-methylbutyrylcarnitine and isoleucine directly associated with hypertension. Baseline salt-sensitivity status predicted changes in 14 metabolites when switching to low-sodium or high-sodium interventions. Among them, glutamate, 1-carboxyethylvaline, 2-methylbutyrylcarnitine, 3-methoxytyramine sulfate, glucose, alpha-ketoglutarate, hexanoylcarnitine, gamma-glutamylisoleucine, gamma-glutamylleucine, and gamma-glutamylphenylalanine directly associated with hypertension. Conversely, serine, histidine, threonate and 5-methyluridine indirectly associated with hypertension. Together, these metabolites explained an additional 7% of hypertension susceptibility when added to a model including traditional risk factors.

CONCLUSIONS

Our findings contribute to the molecular characterization of BP response to sodium and provide novel biological insights into salt-sensitive hypertension.

Discordantly normal ApoB relative to elevated LDL-C in persons with metabolic disorders: A marker of atherogenic heterogeneity

Objective

A significant proportion of persons with metabolic syndrome (MetS), prediabetes, or type 2 diabetes (T2D) do not develop atherosclerotic cardiovascular disease (ASCVD).We sought to determine whether discordantly normal apolipoprotein B (ApoB) relative to elevated LDL-C may help to explain heterogeneity in ASCVD risk among persons with metabolic disorders.

Methods

There were 278 Bogalusa Heart Study participants with MetS (n=95), prediabetes (n=233), or T2D (n=31) and LDL-C ≥100 mg/dL who were free of carotid plaque at baseline (2001-02) and underwent carotid ultrasound at follow-up (2013-16). Multivariable modified Poisson regression estimated the long-term absence of carotid plaque for lower ApoB, continuously and categorically.

Results

Participants were on average 36.1 years old at baseline, 61.5% were women, and 31.7% were black. A total of 50.7% had discordantly normal ApoB (<90 mg/dL) and the mean ApoB and LDL-C concentrations were 91.6 mg/dL and 137.7 mg/dL, respectively. In addition to having higher HDL-C and lower triglyceride values, individuals with ApoB <90 were more likely to maintain persistent absence of plaque compared to those with ApoB ≥90 (73.1% versus 58.4%, p=0.01). Contrastingly, there was no significant difference in the proportion of individuals who remained free of plaque with increasing LDL-C (p=0.45). Independent of traditional risk factors including LDL-C, each 10 mg/dL lower ApoB (RR=1.11, 95% CI: 1.03-1.19) and ApoB <90 (RR=1.22, 95% CI: 1.00-1.43) were significantly associated with the persistent absence of carotid plaque.

Conclusions

One-half of young persons with metabolic disorders and elevated LDL-C had discordantly normal ApoB and a low burden of carotid atherosclerosis over 13 years, suggesting that ApoB better represents the atherogenic lipid burden compared to LDL-C in this patient population. These results suggest a utility for assessing whether routine ApoB measurement can improve ASCVD risk stratification in young persons with metabolic disorders who have high triglycerides and low HDL-cholesterol.

Early Contributors to Healthy Arterial Aging Versus Premature Atherosclerosis in Young Adults: The Bogalusa Heart Study

Background

Early identification of healthy arterial aging versus premature atherosclerosis is important for optimal atherosclerotic cardiovascular disease risk stratification and prevention. We sought to identify predictors for the long‐term absence of carotid plaque among young adults.

Methods and Results

We included 508 participants from the Bogalusa Heart Study without clinical atherosclerotic cardiovascular disease who were free of carotid plaque at baseline (2001–2002) and underwent ultrasound imaging at follow‐up (2013–2016). Modified Poisson regression estimated the persistent absence of plaque over 12.8 years. Participants were on average age 36.2 years at baseline, 64% were women, and 29% were Black. Although nearly all participants (97%) had a 10‐year atherosclerotic cardiovascular disease risk <7.5%, there were 162 people (32%) who developed premature atherosclerosis. Aside from younger age (risk ratio [RR], 1.21; 95% CI, 1.07–1.36, per 10 years) and a total cholesterol/high‐density lipoprotein cholesterol ratio <3.5 (RR, 1.15; 95% CI, 1.01–1.30), normal values of traditional risk factors did not predict long‐term absence of plaque. Independent from traditional markers including glomerular filtration rate, serum calcium‐phosphate product (RR, 1.07; 95% CI, 1.01–1.14, per 1‐SD lower), phosphate (RR, 1.15; 95% CI, 1.03–1.29, per 1 mg/dL lower), and dietary sodium <2300 mg/day (RR, 1.20; 95% CI, 1.02–1.41) were significantly associated with the non‐development of plaque.

Conclusions

Nearly one third of young adults with a low burden of traditional risk factors developed premature atherosclerosis. Beyond younger age and an ideal lipoprotein profile, lower calcium‐phosphate homeostasis and low sodium intake were associated with long‐term absence of carotid plaque. These results suggest that dietary and intrinsic minerals are early contributors to the development of arterial aging phenotypes.

Consumption of animal and plant foods and risk of left ventricular diastolic dysfunction: the Bogalusa Heart Study

AIMS

Left ventricular diastolic dysfunction (LVDD) is an early heart failure with preserved ejection fraction (HFpEF) phenotype that is reversible. Identifying dietary predictors associated with LVDD in diverse populations may help broadly improve HFpEF primary prevention.

METHODS AND RESULTS

This longitudinal analysis included 456 individuals of the Bogalusa Heart Study (27% Black, 63% women, baseline age = 36.1 ± 4.4 years). Diet was measured at baseline through food frequency questionnaires. LVDD was defined at follow-up (median = 12.9 years) through echocardiographic measurement of the E/A ratio, E/e' ratio, isovolumic relaxation time, and deceleration time. Multivariable-adjusted logistic regression estimated the risk of LVDD according to dietary predictor, adjusting for traditional cardiovascular disease risk factors. Compared with the lowest tertile, participants in the middle tertile of total protein (OR = 3.30, 95% CI: 1.46, 7.45) and animal protein (OR = 2.91, 95% CI: 1.34, 6.34) consumption experienced the highest risk of LVDD. There was a 77% and 56% lower risk of LVDD for persons in the middle vs. lowest tertile of vegetable (OR = 0.23, 95% CI: 0.11, 0.49) and legume consumption (OR = 0.44, 95% CI: 0.22, 0.85), respectively. Total protein, animal protein, processed meat, and egg consumption indicated a quadratic trend towards increased risk of LVDD, while legume and vegetable intake conferred a quadratic trend towards decreased risk of LVDD (all quadratic P < 0.05).

CONCLUSIONS

Diets higher in animal foods and lower in plant foods are associated with an increased risk for LVDD. These findings suggest threshold effects of diet on LVDD, past which more traditional cardiometabolic determinants occupy a larger role in HFpEF risk.

Precision of Measurements Performed by a Cadre of Anthropometrists Trained for a Large Household Nutrition Survey in Ethiopia

BACKGROUND

Well-trained anthropometrists are essential for the delivery of high-quality anthropometric data used to evaluate public health nutrition interventions. Scant data are currently available on the precision of data collected by large teams of anthropometrists employed for nutrition surveys in low-income country settings.

OBJECTIVES

The purpose of this study was to assess the precision of child midupper arm circumference (MUAC) and length/height measurements taken by fieldworkers training for nutrition survey deployment.

METHODS

Following 3 d of training, an anthropometry standardization exercise was conducted in small teams of trainees at 7 sites in the Amhara region of Ethiopia. In groups of 2-4, trainee anthropometrists (n = 79) each measured 16 children aged 6-47 mo (n = 336) twice for MUAC and length/height. Both intraobserver and interobserver precision were analyzed using technical error of measurement (TEM), relative TEM, coefficient of reliability (R), and repeatability metrics. Bland-Altman limits of agreement were calculated for intraobserver measurements.

RESULTS

Intraobserver TEM was between 0.00 and 0.57 cm for MUAC (Bland-Altman 95% limits of agreement: -0.50 to 0.54 cm) and between 0.04 and 2.58 cm for length/height measurements (Bland-Altman 95% limits of agreement: -1.43 to 1.41 cm). Interobserver TEM was between 0.09 and 0.43 cm for MUAC and between 0.06 and 2.98 cm for length/height measurements. A high proportion of trainees achieved intraobserver R >0.95 (MUAC: 95%; length/height: 97%). Most teams also achieved interobserver R >0.95 (MUAC: 90%; length/height: 95%).

CONCLUSIONS

Large numbers of anthropometrists (>75) in low-income settings can attain satisfactory precision in anthropometry following training and standardization. These protocols permit researchers to assess trainees, identify individuals who have not achieved the desired level of precision, and retrain or adjust roles prior to survey deployment.

An untargeted metabolomics study of blood pressure: findings from the Bogalusa Heart Study

OBJECTIVE

To identify novel and confirm previously reported metabolites associated with SBP, DBP, and hypertension in a biracial sample of Bogalusa Heart Study (BHS) participants.

METHODS

We employed untargeted, ultra-high performance liquid chromatography tandem mass spectroscopy metabolomics profiling among 1249 BHS participants (427 African-Americans and 822 whites) with BP and covariable data collected during the 2013 to 2016 visit cycle. A total of 1202 metabolites were tested for associations with continuous and binary BP phenotypes using multiple linear and logistic regression models, respectively, in overall and race-stratified analyses.

RESULTS

A total of 24 novel metabolites robustly associated with BP, achieving Bonferroni-corrected P less than 4.16 × 10 in the overall analysis and consistent effect sizes across race groups. The identified metabolites included three amino acid and nucleotide metabolites from histidine, pyrimidine, or tryptophan metabolism sub-pathways, seven cofactor and vitamin or xenobiotic metabolites from the ascorbate and aldarate metabolism, bacterial/fungal, chemical, and food component sub-pathways, 10 lipid metabolites from the eicosanoid, phosphatidylcholine, phosphatidylethanolamine, and sphingolipid metabolism sub-pathways, and four still unnamed metabolites. Six previously described metabolites were robustly confirmed by our study (Bonferroni-corrected P < 4.95 × 10 and consistent effect directions across studies). Furthermore, previously reported metabolites for SBP, DBP, and hypertension demonstrated 5.92-fold, 4.77-fold, and 4.54-fold enrichment for nominally significant signals in the BHS (P = 3.08 × 10, 5.93 × 10, and 2.30 × 10, respectively).

CONCLUSION

In aggregate, our study provides new information about potential molecular mechanisms underlying BP regulation. We also demonstrate reproducibility of findings across studies despite differences in study populations and metabolite profiling methods.

Serum metabolites associate with physical performance among middle-aged adults: Evidence from the Bogalusa Heart Study

Age-related declines in physical performance predict cognitive impairment, disability, chronic disease exacerbation, and mortality. We conducted a metabolome-wide association study of physical performance among Bogalusa Heart Study participants. Bonferroni corrected multivariate-adjusted linear regression was employed to examine cross-sectional associations between single metabolites and baseline gait speed (N=1,227) and grip strength (N=1,164). In a sub-sample of participants with repeated assessments of gait speed (N=282) and grip strength (N=201), significant metabolites from the cross-sectional analyses were tested for association with change in physical performance over 2.9 years of follow-up. Thirty-five and seven metabolites associated with baseline gait speed and grip strength respectively, including six metabolites that associated with both phenotypes. Three metabolites associated with preservation or improvement in gait speed over follow-up, including: sphingomyelin (40:2) (P=2.6×10^-4) and behenoyl sphingomyelin (d18:1/22:0) and ergothioneine (both P<0.05). Seven metabolites associated with declines in gait speed, including: 1-carboxyethylphenylalanine (P=8.8×10^-5), and N-acetylaspartate, N-formylmethionine, S-adenosylhomocysteine, N-acetylneuraminate, N2,N2-dimethylguanosine, and gamma-glutamylphenylalanine (all P<0.05). Two metabolite modules reflecting sphingolipid and bile acid metabolism associated with physical performance (minimum P=7.6×10^-4). These results add to the accumulating evidence suggesting an important role of the human metabolome in physical performance and specifically implicate lipid, nucleotide, and amino acid metabolism in early physical performance decline.

Serum metabolites associate with lipid phenotypes among Bogalusa Heart Study participants

BACKGROUND AND AIMS

Dyslipidemia has been identified as a major risk factor for cardiovascular disease. We aimed to identify metabolites and metabolite modules showing novel association with lipids among Bogalusa Heart Study (BHS) participants using untargeted metabolomics.

METHODS AND RESULTS

Untargeted ultrahigh performance liquid chromatography-tandem mass spectroscopy was used to quantify serum metabolites of 1 243 BHS participants (816 whites and 427 African-Americans). The association of single metabolites with lipids was assessed using multiple linear regression models to adjust for covariables. Weighted correlation network analysis was utilized to identify modules of co-abundant metabolites and examine their covariable adjusted correlations with lipids. All analyses were conducted according to race and using Bonferroni-corrected α-thresholds to determine statistical significance. Thirteen metabolites with known biochemical identities showing novel association achieved Bonferroni-significance, p < 1.04 × 10^-5, and showed consistent effect directions in both whites and African-Americans. Twelve were from lipid sub-pathways including fatty acid metabolism (arachidonoylcholine, dihomo-linolenoyl-choline, docosahexaenoylcholine, linoleoylcholine, oleoylcholine, palmitoylcholine, and stearoylcholine), monohydroxy fatty acids (2-hydroxybehenate, 2-hydroxypalmitate, and 2-hydroxystearate), and lysoplasmalogens [1-(1-enyl-oleoyl)-GPE (P-18:1) and 1-(1-enyl-stearoyl)-GPE (P-18:0)]. The gamma-glutamylglutamine, peptide from the gamma-glutamyl amino acid sub-pathway, were also identified. In addition, four metabolite modules achieved Bonferroni-significance, p < 1.39 × 10^-3, in both whites and African-Americans. These four modules were largely comprised of metabolites from lipid sub-pathways, with one module comprised of metabolites which were not identified in the single metabolite analyses.

CONCLUSION

The current study identified 13 metabolites and 4 metabolite modules showing novel association with lipids, providing new insights into the physiological mechanisms regulating lipid levels.

Pseudouridine and N-formylmethionine associate with left ventricular mass index: Metabolome-wide association analysis of cardiac remodeling

BACKGROUND

Heart failure (HF) is the fastest growing form of cardiovascular disease both nationally and globally, underlining a need to phenotype subclinical HF intermediaries to improve primary prevention.

OBJECTIVES

We aimed to identify novel metabolite associations with left ventricular (LV) remodeling, one upstream HF intermediary, among a community-based cohort of individuals.

METHODS

We examined 1052 Bogalusa Heart Study participants (34.98% African American, 57.41% female, aged 33.6-57.5 years). Measures of LV mass and relative wall thickness (RWT) were obtained using two-dimensional-guided echocardiographic measurements via validated eqs. LV mass was indexed to height^2.7 to calculate left ventricular mass index (LVMI). Untargeted metabolomic analysis of fasting serum samples was conducted. In combined and ethnicity-stratified analyses, multivariable linear and multinomial logistic regression models tested the associations of metabolites with the continuous LVMI and RWT and categorical LV geometry phenotypes, respectively, after adjusting for demographic and traditional cardiovascular disease risk factors.

RESULTS

Pseudouridine (B = 1.38; p = 3.20 × 10^-5) and N-formylmethionine (B = 1.65; 3.30 × 10^-6) were significantly associated with LVMI in the overall sample as well significant in Caucasians, with consistent effect direction and nominal significance (p < .05) in African Americans. Upon exclusion of individuals with self-report myocardial infarction or congestive HF, we similarly observed a 1.33 g/m^2.7 and 1.52 g/m^2.7 higher LVMI for each standard deviation increase in pseudouridine and N-formylmethionine, respectively. No significant associations were observed for metabolites with RWT or categorical LV remodeling outcomes.

CONCLUSIONS

The current analysis identified novel associations of pseudouridine and N-formylmethionine with LVMI, suggesting that mitochondrial-derived metabolites may serve as early biomarkers for LV remodeling and subclinical HF.

Novel Findings From a Metabolomics Study of Left Ventricular Diastolic Function: The Bogalusa Heart Study

Background

Diastolic dysfunction is one important causal factor for heart failure with preserved ejection fraction, yet the metabolic signature associated with this subclinical phenotype remains unknown.

Methods and Results

Ultra‐high‐performance liquid chromatography–tandem mass spectroscopy was used to conduct untargeted metabolomic analysis of fasting serum samples in 1050 white and black participants of the BHS (Bogalusa Heart Study). After quality control, 1202 metabolites were individually tested for association with 5 echocardiographic measures of left ventricular diastolic function using multivariable‐adjusted linear regression. Measures of left ventricular diastolic function included the ratio of peak early filling velocity to peak late filling velocity, ratio of peak early filling velocity to mitral annular velocity, deceleration time, isovolumic relaxation time, and left atrial maximum volume index (LAVI). Analyses adjusted for multiple cardiovascular disease risk factors and used Bonferroni‐corrected alpha thresholds. Eight metabolites robustly associated with left ventricular diastolic function in the overall population and demonstrated consistent associations in white and black study participants. N‐formylmethionine (B=0.05; P=1.50×10⁻⁷); 1‐methylhistidine (B=0.05; P=1.60×10⁻⁷); formiminoglutamate (B=0.07; P=5.60×10⁻⁷); N2, N5‐diacetylornithine (B=0.05; P=1.30×10⁻⁷); N‐trimethyl 5‐aminovalerate (B=0.04; P=5.10×10⁻⁶); 5‐methylthioadenosine (B=0.04; P=1.40×10⁻⁵); and methionine sulfoxide (B=0.04; P=3.80×10⁻⁶) were significantly associated with the natural log of the ratio of peak early filling velocity to mitral annular velocity. Butyrylcarnitine (B=3.18; P=2.10×10⁻⁶) was significantly associated with isovolumic relaxation time.

Conclusions

The current study identified novel findings of metabolite associations with left ventricular diastolic function, suggesting that the serum metabolome, and its underlying biological pathways, may be implicated in heart failure with preserved ejection fraction pathogenesis.

Novel associations between blood metabolites and kidney function among Bogalusa Heart Study and Multi-Ethnic Study of Atherosclerosis participants

INTRODUCTION

Chronic kidney disease (CKD) is a major public health challenge given its high global prevalence and associated risks of cardiovascular disease and progression to end stage renal disease. Although it is known that numerous metabolic changes occur in CKD patients, identifying novel metabolite associations with kidney function may enhance our understanding of the physiologic pathways relating to CKD.

OBJECTIVES

The objective of this study was to elucidate novel metabolite associations with kidney function among participants of two community-based cohorts with carefully ascertained metabolomics, kidney function, and covariate data.

METHODS

Untargeted ultrahigh-performance liquid chromatography-tandem mass spectrometry was used to detect and quantify blood metabolites. We used multivariate adjusted linear regression to examine associations between single metabolites and creatinine-based estimated glomerular filtration rate (eGFRcr) among 1243 Bogalusa Heart Study (BHS) participants (median eGFRcr: 94.4, 5th-95th percentile: 66.0-119.6 mL/min/1.73 m²). Replication, determined by statistical significance and consistent effect direction, was tested using gold standard measured glomerular filtration rate (mGFR) among 260 Multi-Ethnic Study of Atherosclerosis (MESA) participants (median mGFR: 72.0, 5th-95th percentile: 43.5-105.0 mL/min/1.73 m²). All analyses used Bonferroni-corrected alpha thresholds.

RESULTS

Fifty-one novel metabolite associations with kidney function were identified, including 12 from previously unrelated sub-pathways: N6-carboxymethyllysine, gulonate, quinolinate, gamma-CEHC-glucuronide, retinol, methylmalonate, 3-hydroxy-3-methylglutarate, 3-aminoisobutyrate, N-methylpipecolate, hydroquinone sulfate, and glycine conjugates of C₁₀H₁₂O₂ and C₁₀H₁₄O₂(1). Significant metabolites were generally inversely associated with kidney function and smaller in mass-to-charge ratio than non-significant metabolites.

CONCLUSION

The 51 novel metabolites identified may serve as early, clinically relevant, kidney function biomarkers.

Novel serum metabolites associate with cognition phenotypes among Bogalusa Heart Study participants

BACKGROUND

Metabolomics study provides an opportunity to identify novel molecular determinants of altered cognitive function.

METHODS

During 2013 to 2016 Bogalusa Heart Study (BHS) visit, 1,177 participants underwent untargeted, ultrahigh performance liquid chromatography-tandem mass spectroscopy metabolomics profiling. Global cognition and five cognition domains were also assessed. The cross-sectional associations of single metabolites with cognition were tested using multiple linear regression models. Weighted correlation network analysis was used to examine the covariable-adjusted correlations of modules of co-abundant metabolites with cognition. Analyses were conducted in the overall sample and according to both ethnicity and sex.

RESULTS

Five known metabolites and two metabolite modules robustly associated with cognition across overall and stratified analyses. Two metabolites were from lipid sub-pathways including fatty acid metabolism [9-hydroxystearate; minimum P-value (min-P)=1.11×10-5], and primary bile acid metabolism (glyco-alpha-muricholate; min-P=4.10×10-5). One metabolite from the glycogen metabolism sub-pathway (maltose; min-P=9.77×10-6), one from the polyamine metabolism sub-pathway (N-acetyl-isoputreanine; min-P=1.03×10-5), and one from the purine metabolism sub-pathway (7-methylguanine; min-P=1.19×10-5) were also identified. Two metabolite modules reflecting bile acid metabolism and androgenic steroids correlated with cognition (min-P=5.00×10-4 and 3.00×10-3, respectively).

CONCLUSION

The novel associations of 5 known metabolites and 2 metabolite modules with cognition provide insights into the physiological mechanisms regulating cognitive function.

Postural hand tremor and incident hypertension in young to middle-aged adults: the Bogalusa heart study

BACKGROUND

Hand tremor and blood pressure (BP) are both increased by adrenergic stimulation and reduced by β-blockade, indicating that they may share a common underlying pathophysiology.

METHODS

We prospectively examined the relationship between postural hand tremor and incident hypertension in a community-based cohort of 715 (184 blacks and 531 whites) adults without hypertension and not using medications to control tremor (e.g. β-blockers). At baseline, tremor was measured with participants holding a laser pointer aimed at a sheet of Polaroid film 8 feet away with arm outstretched for 8 s in a darkened room, and characterized by the width of the circle diameter encompassing all exposures and enumeration of exposure dots in the same area. Incident hypertension was defined as new elevation of BP (SBP ≥ 140 or DBP ≥ 90 mmHg, based on an average of six readings over two visits) or antihypertensive medication use.

RESULTS

During a median follow-up of 6.4 years, 198 (69 blacks and 129 whites) participants developed hypertension. Tremor measurements (by quartile) were positively associated with incident hypertension after adjustment for baseline demographics, lifestyle characteristics, and BP. There was significant interaction by race (P = 0.01). Among whites, tremor was positively associated with incident hypertension [hazard ratio highest vs. lowest quartile: 2.50 (95% confidence interval: 1.40-4.48) dot method and 3.24 (1.78-5.90) circular method; both P trend <0.01]. Among blacks, tremor was not associated with hypertension.

CONCLUSION

In this community-based cohort, postural hand tremor was strongly associated with the risk of incident hypertension among whites and merits further study as a potential indicator of risk for hypertension.

Gut Microbiome Associates With Lifetime Cardiovascular Disease Risk Profile Among Bogalusa Heart Study Participants

RATIONALE

Few studies have systematically assessed the influence of gut microbiota on cardiovascular disease (CVD) risk.

OBJECTIVE

To examine the association between gut microbiota and lifetime CVD risk profile among 55 Bogalusa Heart Study participants with the highest and 57 with the lowest lifetime burdens of CVD risk factors.

METHODS AND RESULTS

16S ribosomal RNA sequencing was conducted on microbial DNA extracted from stool samples of the Bogalusa Heart Study participants. α Diversity, including measures of richness and evenness, and individual genera were tested for associations with lifetime CVD risk profile. Multivariable regression techniques were used to adjust for age, sex, and race (model 1), along with body mass index (model 2) and both body mass index and diet (model 3). In model 1, odds ratios (95% confidence intervals) for each SD increase in richness, measured by the number of observed operational taxonomic units, Chao 1 index, and abundance-based coverage estimator, were 0.62 (0.39-0.99), 0.61 (0.38-0.98), and 0.63 (0.39-0.99), respectively. Associations were consistent in models 2 and 3. Four genera were enriched among those with high versus low CVD risk profile in all models. Model 1 P values were 2.12×10(-3), 7.95×10(-5), 4.39×10(-4), and 1.51×10(-4) for Prevotella 2, Prevotella 7, Tyzzerella, and Tyzzerella 4, respectively. Two genera were depleted among those with high versus low CVD risk profile in all models. Model 1 P values were 2.96×10(-6) and 1.82×10(-4) for Alloprevotella and Catenibacterium, respectively.

CONCLUSIONS

The current study identified associations of overall microbial richness and 6 microbial genera with lifetime CVD risk.

Variability and rapid increase in body mass index during childhood are associated with adult obesity

BACKGROUND

Body mass index (BMI) in childhood predicts obesity in adults, but it is unknown whether rapid increase and variability in BMI during childhood are independent predictors of adult obesity.

METHODS

The study cohort consisted of 1622 Bogalusa Heart Study participants (aged 20 to 51 years at follow-up) who had been screened at least four times during childhood (aged 4-19 years). BMI rate of change during childhood for each individual was assessed by mixed models; BMI residual standard deviation (RSD) during childhoodwas used as a measure of variability. The average follow-up period was 20.9 years.

RESULTS

One standard deviation increase in rate of change in BMI during childhood was associated with 1.39 [95% confidence interval (CI): 1.17-1.61] kg/m(2) increase in adult BMI and 2.98 (95% CI: 2.42-3.56) cm increase in adult waist circumference, independently of childhood mean BMI. Similarly, one standard deviation increase in RSD in BMI during childhood was associated with 0.46 (95% CI: 0.23-0.69) kg/m(2) increase in adult BMI and 1.42 (95% CI: 0.82-2.02) cm increase in adult waist circumference. Odds ratio for adult obesity progressively increased from the lowest to the highest quartile of BMI rate of change or RSD during childhood (P for trend < 0.05 for both).

CONCLUSIONS

Rapid increase and greater variability in BMI during childhood appear to be independent risk factors for adult obesity. Our findings have implications for understanding body weight regulation and obesity development from childhood to adulthood.

Which measures of adiposity predict subsequent left ventricular geometry? Evidence from the Bogalusa Heart Study

BACKGROUND AND AIMS

Left ventricular (LV) hypertrophy increases the risk of future cardiovascular events. The relationship between obesity in young adulthood and later LV geometry is unknown. We examined the association between long-term changes in measures of adiposity and subsequent LV geometry among 1073 young adults from the Bogalusa Heart Study.

METHODS AND RESULTS

Echocardiography-measured LV geometry was classified into normal (N = 796), concentric remodeling (N = 124), eccentric hypertrophy (N = 99), and concentric hypertrophy (N = 54) by integrating relative wall thickness and LV mass index. The mean age of our population was 38 years when the LV geometry was measured. Body mass index (BMI) increased by a mean of 4.9 kg/m(2) over a median of 20 years, waist circumference (WC) by 10.9 cm over 17 years, waist/hip ratio by 0.02 over 10 years, waist/height ratio by 0.06 over 17 years, abdominal height by 0.9 cm over 10 years, body fat (BF) percentage by 12.7% over 20 years, and Visceral Adiposity Index by 0.30 over 17 years. In polytomous logistic regression models corrected for multiple comparisons, participants with one-standard-deviation increases in BMI, WC, waist/height ratio, and BF had 2.00 (95% confidence interval (CI): 1.53-2.61), 1.33 (1.06-1.68), 1.35 (1.07-1.70), and 1.60 (1.26-2.03) times the risk of eccentric hypertrophy, respectively, after adjustment for demographic, lifestyle, metabolic risk factors, and follow-up time. Likewise, the rates of change in BMI, WC, waist/height ratio, and BF were associated with eccentric hypertrophy. There was no association with concentric remodeling or concentric hypertrophy.

CONCLUSIONS

Our findings suggest that increases in BMI, WC, waist/height ratio, and BF were strong predictors of eccentric hypertrophy in middle age.

The relation of BMI and skinfold thicknesses to risk factors among young and middle-aged adults: the Bogalusa Heart Study

OBJECTIVE

Although adverse levels of cardiovascular disease risk factors are related to skinfold thicknesses and BMI among adults, the relative strengths of these associations are unknown. We examine whether the triceps and subscapular skinfold thicknesses are more strongly related to adult levels of lipids, fasting insulin and blood pressure than BMI.

DESIGN AND SUBJECTS

Cross-sectional (n =3318) and longitudinal (n =1593) analyses of 18- to 44-year-olds examined in the Bogalusa Heart Study from 1983 to 2002. Principal components analysis was used to derive a summary index of the six examined risk factors (triglycerides, low- and high-density lipoprotein cholesterol, insulin, and systolic and diastolic blood pressures).

RESULTS

The magnitudes of the differences were generally small, but all comparisons indicated that BMI was at least as strongly related to adverse risk factor levels as was the sum of subscapular and triceps skinfold thicknesses (SF sum). For example, adjusted cross-sectional associations with the risk factor summary were r = 0.55 (BMI) and r = 0.49 (SF sum), p < 0.001 for difference between correlations. Similar differences were seen in longitudinal analyses, with changes in the risk factor summary being more strongly associated with changes in BMI (r =0.50) than with changes in the SF sum (r = 0.38).

CONCLUSION

BMI appears to be at least as accurate as skinfold thicknesses in identifying metabolic risk among adults. The advantages of BMI should be considered in the design and interpretation of clinical and epidemiologic studies.

Relation of body mass index and skinfold thicknesses to cardiovascular disease risk factors in children: the Bogalusa Heart Study

BACKGROUND

Adverse levels of cardiovascular disease (CVD) risk factors are related to skinfold thicknesses and body mass index (BMI) among children, but the relative strengths of these associations are unknown.

OBJECTIVE

The objective was to determine whether the sum of the triceps and subscapular skinfold thicknesses (SF sum) is more strongly related to levels of 6 risk factors (triglycerides, LDL and HDL cholesterol, insulin, and systolic and diastolic blood pressure) than is BMI.

DESIGN

Cross-sectional analyses of schoolchildren examined in the Bogalusa Heart Study from 1981 to 1994 (n = 6866) were conducted. A risk factor summary index was derived by using principal components analysis.

RESULTS

After race, sex, study period, and age were controlled for, almost all comparisons indicated that BMI was more strongly related to risk factor levels than was the SF sum. Although the differences were generally small, many were statistically significant. Associations with the risk factor summary, for example, were r = 0.50 for BMI and r = 0.47 for SF sum (P < 0.001 for difference). Furthermore, an adverse risk factor summary was observed among 62% of the children with the highest (upper 5%) BMI levels but among only 54% of children with the highest SF sum levels.

CONCLUSIONS

BMI is at least as accurate as SF sum in identifying children and adolescents who are at metabolic risk. Because of the training and errors associated with skinfold-thickness measurements, the advantages of BMI should be considered in the design and interpretation of clinical and epidemiologic studies.

Reliability of anthropometric measurements in the WHO Multicentre Growth Reference Study

AIM

To describe how reliability assessment data in the WHO Multicentre Growth Reference Study (MGRS) were collected and analysed, and to present the results thereof.

METHODS

There were two sources of anthropometric data (length, head and arm circumferences, triceps and subscapular skinfolds, and height) for these analyses. Data for constructing the WHO Child Growth Standards, collected in duplicate by observer pairs, were used to calculate inter-observer technical error of measurement (TEM) and the coefficient of reliability. The second source was the anthropometry standardization sessions conducted throughout the data collection period with the aim of identifying and correcting measurement problems. An anthropometry expert visited each site annually to participate in standardization sessions and provide remedial training as required. Inter- and intra-observer TEM, and average bias relative to the expert, were calculated for the standardization data.

RESULTS

TEM estimates for teams compared well with the anthropometry expert. Overall, average bias was within acceptable limits of deviation from the expert, with head circumference having both lowest bias and lowest TEM. Teams tended to underestimate length, height and arm circumference, and to overestimate skinfold measurements. This was likely due to difficulties associated with keeping children fully stretched out and still for length/height measurements and in manipulating soft tissues for the other measurements. Intra- and inter-observer TEMs were comparable, and newborns, infants and older children were measured with equal reliability. The coefficient of reliability was above 95% for all measurements except skinfolds whose R coefficient was 75-93%.

CONCLUSION

Reliability of the MGRS teams compared well with the study's anthropometry expert and published reliability statistics.

Accuracy of blood pressure measurement and anthropometry among volunteer observers in a large community survey

The Busselton Survey is a population survey that is held about every three years. In 1994-1995 a re-survey was held of all past participants and 8,502 attended. Financial constraints precluded employing staff for data collection for blood pressure and anthropometry, these therefore were collected by unpaid lay volunteers. Quality control by a health professional was critical to the assessment and maintenance of accuracy in these measurements. For blood pressure three readings were taken simultaneously by a quality control person and the volunteer using a dual stethoscope. Duplicate anthropometric measurements were taken by a criterion anthropometrist and the volunteer. Inter and intra-observer technical errors of measurement (TEM) were calculated. Sixty-two volunteers were trained to take BP measurements; of these, 38 collected data, and 63 were trained in anthropometry; of these, 30 were suitable as measurers. Training was conducted on a group and individual basis by the quality assurance person for the study both in the Perth metropolitan area and rural Busselton. The TEM for SBP was 1.6 mm Hg (SD 1.0 mm Hg) and 1.5 mm Hg (SD 0.8) for DBP. For skin-folds intra-observer TEM ranged from 0.6 mm to 1.0 mm. Between-observer TEM ranged from 2.1 mm to 5.4 mm. For limb and waist circumferences, intra-observer TEM ranged from 0.3 cm to 1.6 cm. Between-observer TEM for circumferences ranged from 0.5 cm to 1.9 cm. Unpaid volunteer measurers can, if carefully trained and supervised, provide acceptable blood pressure data and anthropometry in large population surveys.

Ambulatory blood pressure measurements in children and young adults selected by high and low casual blood pressure levels and parental history of hypertension: the Bogalusa Heart Study

Ambulatory blood pressure measurements were obtained in 57 children and young adults selected by prior high or low casual blood pressure levels and parental history of hypertension. Considerable variation in blood pressure levels occurred over 24 hours, with generally higher levels occurring in those so selected. Parental history had a small influence on higher levels, although statistical significance was not shown. Persons with higher blood pressure levels did not reach levels as low during sleep, especially with regard to the systolic measurement, and a greater variability was noted in those selected for higher levels. Although differentiation of persons with high and low blood pressure levels can be obtained by noting average levels persisting above a cut point, for example, 140/85, in growing children an arbitrary 90th percentile based on age, height, and weight may be more appropriate. Ambulatory monitoring showed that young persons, selected by casual measurements as having high blood pressure, have a greater percentage of high levels persisting over a 24-hour period, comprising a greater blood pressure load. These observations also showed that even two series of casual measurements may misclassify a person as having hypertension. Ambulatory blood pressure monitoring will enhance understanding of the early natural history of hypertension and allow improved prevention of the disease.

Relation of serum lipoprotein lipids and apolipoproteins to obesity in children: the Bogalusa Heart Study

BACKGROUND

The relationship of serum lipoprotein lipids and apolipoproteins to obesity was studied in a biracial sample of 2,816 children of ages 5-17 in Bogalusa, Louisiana.

METHODS

Two measures of obesity were used: fatness (subscapular skinfold thickness) and fat centrality (the ratio of subscapular to triceps skinfold thickness). Plasma insulin and glucose were included as metabolic markers related to obesity.

RESULTS

The obesity associations were relatively strong with insulin (rs = 0.29, P less than 0.001, skinfold; rs = 0.15, P less than 0.001, skinfold ratio) and triglycerides (rs = 0.25, P less than 0.001, skinfold; rs = 0.19, P less than 0.001, skinfold ratio). The relationships of serum low-density lipoprotein cholesterol (LDL-C) (rs = 0.17, P less than 0.001, skinfold; rs = 0.13, P less than 0.001, skinfold ratio) and apolipoprotein (apo) B (rs = 0.16, P less than 0.001, skinfold; rs = 0.13, P less than 0.001, skinfold ratio) with the obesity measures were of lesser magnitude, but persisted after adjustment for insulin and triglycerides. The inverse association of obesity to serum high-density lipoprotein cholesterol (HDL-C) (rs = -0.13, P less than 0.001, both skinfold and skinfold ratio) and apo A-I (rs = -0.04, P = 0.03, skinfold; rs = -0.05, P = 0.004, skinfold ratio) was significant only before adjustment for insulin and serum triglycerides. Multiple linear regression of obesity measures showed that, like insulin, serum triglycerides had consistently higher standardized coefficients than LDL-C, HDL-C, apo B, and apo A-I. Apo A-I and apo B added only a small amount (less than 2%) of information to the relationship of serum lipoproteins with obesity measures.

CONCLUSION

These results indicate that serum very-low-density lipoprotein (VLDL) levels are directly and independently related to obesity. The well-known inverse association between obesity and serum HDL-C is not independent, but secondary to the elevated VLDL or triglyceride levels associated with obesity. While associations of obesity and lipoprotein cholesterol are found, far fewer occur with apolipoproteins, especially Apo A-I. Interesting race and sex differences in the relationship of obesity to serum lipoproteins and apoproteins are noted, being greater among white children and more consistent in white males.

Body fatness and risk for elevated blood pressure, total cholesterol, and serum lipoprotein ratios in children and adolescents

BACKGROUND

Recent studies have shown considerable variation in body fatness among children and adolescents defined as obese by a percentile rank for skinfold thickness.

METHODS

We examined the relationship between percent body fat and risk for elevated blood pressure, serum total cholesterol, and serum lipoprotein ratios in a biracial sample of 3320 children and adolescents aged 5 to 18 years. Equations developed specifically for children using the sum of subscapular (S) and triceps (T) skinfolds were used to estimate percent fat. The S/T ratio provided an index of trunkal fat patterning.

RESULTS

Significant overrepresentation (greater than 20%) of the uppermost quintile (UQ) for cardiovascular disease (CVD) risk factors was evident at or above 25% fat in males (32.2% to 37.3% in UQ) and at or above 30% fat in females (26.6% to 45.4% in UQ), even after adjusting for age, race, fasting status, and trunkal fat patterning.

CONCLUSIONS

These data support the concept of body fatness standards in White and Black children and adolescents as significant predictors of CVD risk factors. Potential applications of these obesity standards include epidemiologic surveys, pediatric health screenings, and youth fitness tests.

Children's cardiovascular reactivity: stability of racial differences and relation to subsequent blood pressure over a one-year period

After measuring blood pressure and heart rate at rest and during a video game procedure in 477 children enrolled in 3rd grade, 434 (91%) children had these measurements repeated a year later in 4th grade. Black children demonstrated greater blood pressure and heart rate reactivity than White children in both years, and an increase in heart rate reactivity from 3rd to 4th grade. Gender effects were inconsistent. Systolic and diastolic blood pressures during the video game were more highly correlated from year-to-year than were the resting measures. Regression analysis indicated that systolic reactivity was significantly related to subsequent systolic pressure at rest, particularly among Black girls. Diastolic reactivity was associated with subsequent resting diastolic pressure only among White children. Associations between reactivity and future blood pressure were independent of initial resting blood pressure. This study suggests that cardiovascular reactivity to psychological stress may be one important factor in future level of blood pressure and that the increased heart rate reactivity of Black children may be associated with the prevalence of hypertension among Black adults.