Candy consumption in childhood is not predictive of weight, adiposity measures or cardiovascular risk factors in young adults: the Bogalusa Heart Study.

BACKGROUND: There are limited data available on the longitudinal relationship between candy consumption by children on weight and other cardiovascular risk factors (CVRF) in young adults. The present study investigated whether candy consumption in children was predictive of weight and CVRF in young adults. METHODS: A longitudinal sample of children 10 years (n = 355; 61% females; 71% European-Americans, 29% African-Americans) who participated in cross-sectional surveys from 1973 to 1984 (baseline) and in one of two surveys (follow-ups) as young adults [19-38 years; mean (SD) = 23.6 (2.6) years] in Bogalusa, LA, were studied. Dietary data were collected using 24-h dietary recalls at baseline and at one follow-up survey; a food frequency questionnaire was used in the other follow-up survey. Candy consumers were those consuming any amount of candy. Candy consumption was calculated (g day(-1) ) from baseline 24-h dietary recalls, and was used as a covariate in the adjusted linear mixed models. Dependent variables included body mass index (BMI) and CVRF measured in young adults. RESULTS: At baseline, 92% of children reported consuming candy [46 (45) g day(-1)]; the percentage decreased to 67% [20 (30) g day(-1)] at follow-up. No longitudinal relationship was shown between baseline candy consumption and BMI or CVRF in young adults, suggesting that candy consumption was not predictive of health risks later in life. CONCLUSIONS: The consumption of nutrient rich foods consistent with dietary recommendations is important, although modest amounts of candy can be added to the diet without potential adverse long-term consequences to weight or CVRF. Additional studies are needed to confirm these results.

The association of c-reactive protein with arterial compliance in asymptomatic young adults: the Bogalusa heart study.

Atherogeneis is a chronic progressive syndrome caused by endothelial dysfunction, vascular inflammation, vessel wall remodeling and eventual vascular flow compromise. Emerging data suggest that arterial compliance inversely correlates with atherogenesis and cardiovascular (CV) events. However, information is scant on the association of chronic systemic inflammation with arterial elasticity in young asymptomatic adults. The association of hsC-reactive protein (CRP) and central-vascular compliance was studied in 641 individuals (45.2% males; 71.8% whites), aged 31-43 years enrolled in the Bogalusa Heart Study. The measured variables included large-artery compliance (capacitive, C1), representative of the aorta and its major branches; and small-artery compliance (oscillatory, C2), representative of the distal part of the circulation; hsCRP, as a measure of systemic inflammation; along with traditional CV risk factor variables. Significant race and sex differences were noted for C1 (white males>black males P-value <0.0001; males>females P-value 0.04), C2 (whites>blacks P-value 0.0004; males>females P-value<0.0001) and hsCRP (blacks>whites P-value 0.03; females>males P-value 0.002). Mean values of C1 in subjects with high hsCRP levels (>3 mg l(-1)) were significantly lower than those with average (1-3 mg l(-1)) and low levels (<1 mg l(-1)) (14.2 ml per mmHg × 10 versus 15.2 ml per mm Hg × 10 versus 15.7 ml per mmHg × 10, P for trend=0.02), after adjusting for age, race, sex and body surface area (BSA). hsCRP showed a trend toward inverse correlation with C1 (-0.07, P=0.07) but no such trend for C2, after adjusting for race and sex. In the multivariate linear regression model, adding age, race, sex, BSA, mean arterial pressure, insulin resistance, lipoprotein variables and smoking status, the effect persisted between C1 and hsCRP (ß=-0.35, P=0.01). In an asymptomatic population of young adults, hsCRP predicts reduced large-artery compliance (C1). These findings support the role of systemic inflammation in early pathological changes in artery wall in atherogenesis. Small-artery compliance (C2) however did not correlate with hsCRP.

Common genetic variation near the connexin-43 gene is associated with resting heart rate in African Americans: a genome-wide association study of 13,372 participants.

BACKGROUND: Genome-wide association studies have identified several genetic loci associated with variation in resting heart rate in European and Asian populations. No study has evaluated genetic variants associated with heart rate in African Americans. OBJECTIVE: To identify novel genetic variants associated with resting heart rate in African Americans. METHODS: Ten cohort studies participating in the Candidate-gene Association Resource and Continental Origins and Genetic Epidemiology Network consortia performed genome-wide genotyping of single nucleotide polymorphisms (SNPs) and imputed 2,954,965 SNPs using HapMap YRI and CEU panels in 13,372 participants of African ancestry. Each study measured the RR interval (ms) from 10-second resting 12-lead electrocardiograms and estimated RR-SNP associations using covariate-adjusted linear regression. Random-effects meta-analysis was used to combine cohort-specific measures of association and identify genome-wide significant loci (P≤2.5×10(-8)). RESULTS: Fourteen SNPs on chromosome 6q22 exceeded the genome-wide significance threshold. The most significant association was for rs9320841 (+13 ms per minor allele; P = 4.98×10(-15)). This SNP was approximately 350 kb downstream of GJA1, a locus previously identified as harboring SNPs associated with heart rate in Europeans. Adjustment for rs9320841 also attenuated the association between the remaining 13 SNPs in this region and heart rate. In addition, SNPs in MYH6, which have been identified in European genome-wide association study, were associated with similar changes in the resting heart rate as this population of African Americans. CONCLUSIONS: An intergenic region downstream of GJA1 (the gene encoding connexin 43, the major protein of the human myocardial gap junction) and an intragenic region within MYH6 are associated with variation in resting heart rate in African Americans as well as in populations of European and Asian origin.

The association of variants in the FTO gene with longitudinal body mass index profiles in non-Hispanic white children and adolescents.

OBJECTIVE: To investigate possible age-related changes in associations between polymorphisms in the fat mass and obesity-associated (FTO) gene and higher body mass index (BMI). DESIGN AND SUBJECTS: Multilevel mixed regression models were used to examine associations between four FTO variants and longitudinal BMI profiles in non-Hispanic white and African American children and adolescents 8-17 years of age from two different longitudinal cohort studies, the Bogalusa Heart Study (BHS) and Project HeartBeat! (PHB). In the BHS, there were 1551 examinations of 478 African Americans and 3210 examinations of 1081 non-Hispanic whites; in PHB, there were 971 examinations of 131 African Americans and 4458 examinations of 505 non-Hispanic whites. RESULTS: In African Americans, no significant FTO associations with BMI were found. In non-Hispanic whites, linkage disequilibrium among all four variants made haplotype analysis superfluous, so we focused on the single-nucleotide polymorphism, rs9939609. In longitudinal multilevel models, the A/A genotype of rs9939609 was associated with higher BMI in non-Hispanic whites in both cohorts at all ages. A significant age-by-genotype interaction found only in the BHS cohort predicted that in those with the A/A genotype, BMI would be ∼0.7 kg m(-2) higher at age 8 and ∼1.6 kg m(-2) higher at age 17 than in those with A/T or T/T genotypes. The design of PHB limited follow-up of any single individual to 4 years, and may have reduced the ability to detect any age-by-genotype interaction in this cohort. CONCLUSIONS: The A/A genotype of rs9939609 in the FTO gene is associated with higher longitudinal BMI profiles in non-Hispanic whites from two different cohorts. The association may change with age, with the A/A genotype being associated with a larger BMI difference in late adolescence than in childhood, though this was observed only in the BHS cohort and requires verification.

Longitudinal versus cross-sectional evaluations of leukocyte telomere length dynamics: age-dependent telomere shortening is the rule.

BACKGROUND: Leukocyte telomere length (LTL) is considered a biomarker of human aging and based on cross-sectional studies it shortens with age. However, longitudinal studies reported that many adults display LTL lengthening. METHODS: Using Southern blots, we compared cross-sectional rates of age-related LTL change across a ∼20 year age range with those based on longitudinal evaluations in three surveys (S1, S2, and S3) with three time intervals: S1-S2 (5.8 years), S2-S3 (6.6 years), and S1-S3 (12.4 years). Hierarchical linear modeling was used to explore LTL dynamics using LTL data from S1, S2, and S3. RESULTS: Cross-sectionally, mean LTL shortenings were 24.6, 25.4, and 23.6 bp/y at S1, S2, and S3, respectively. Longitudinally, more variation was observed in the rate of LTL change during the shorter than longer follow-up periods. Furthermore, using simple differences in LTL, 14.4% and 10.7% of individuals displayed LTL lengthening during S1-S2 and S2-S3, respectively, but only 1.5% during S1-S3 (p < 0.001). The estimated mean rate of LTL shortening based on averaging empirical Bayes' estimates of LTL from a parsimonious hierarchical linear modeling model was 31 bp/y with a range from 23 to 47 bp/y with none of the participants showing LTL lengthening over the average 12.4 years of follow-up. CONCLUSIONS: As aging displays a unidirectional progression, it is unlikely that LTL elongates with age. LTL elongation in longitudinal studies primarily reflects measurement errors of LTL in relation to the duration of follow-up periods.

The association of birth weight with arterial stiffness at mid-adulthood: the Bogalusa Heart Study.

BACKGROUND: Birth weight has been found to predict cardiovascular morbidity and mortality. Pulse wave velocity (PWV), a marker of arterial stiffness, has been associated with cardiovascular risk factors. An association between birth weight and blood pressure (BP) has previously been reported. In this study, the association of birth weight with PWV, and the relationship between birth weight, pulse wave velocity and BP in mid-adulthood were investigated. METHODS: The Bogalusa Heart Study (BHS) is a population-based longitudinal study to investigate the natural development of cardiovascular risk factors. In the 2001 survey, brachial-ankle PWV (baPWV) was measured as an indicator of arterial stiffness. Of the 1203 participants in that survey, 707 had complete data on birth weight and PWV, which were utilised for this study. RESULTS: In this study, birth weight was inversely correlated with baPWV, pulse pressure, and systolic and diastolic BP (r = -0.10; r = -0.10; r = -0.13 and r = -0.09, respectively; p< or =0.01 for all). After adjustment, birth weight was inversely associated with baPWV. On average, baPWV decreased by 0.23 m/s (95% CI -0.44 to -0.03 m/s) for each 1 kg increase in birth weight. Birth weight (inversely) and baPWV were independently associated with systolic BP (B = -2.05; 95% CI -3.27 to -0.84 and B = 2.99; 95% CI 2.58 to 3.40 respectively). CONCLUSIONS: Lower birth weight is associated with higher baPWV. The link between birth weight and systolic BP may be partially explained by the association of birth weight with PWV.

The contribution of childhood obesity to adult carotid intima-media thickness: the Bogalusa Heart Study.

OBJECTIVE: Although obese children are at increased risk for coronary heart disease in later life, it is not clear if the association results from the persistence of childhood obesity into adulthood. We examined the relation of both childhood and adult levels of body mass index (BMI, kg m(-2)) to carotid intima-media thickness (IMT) measured at the (mean) age of 36 years. DESIGN AND SUBJECTS: Prior to the determination of adult IMT, the 1142 participants had been examined 7 (mean) times in the Bogalusa Heart Study. MEASUREMENTS: In addition to BMI, levels of lipids, lipoproteins and blood pressure were measured at each examination. Cumulative levels of each risk factor were based on the areas under the individual growth curves calculated using multilevel models for repeated (BMI) measurements. We then examined the relation of these cumulative levels to adult IMT. RESULTS: Carotid IMT was associated with cumulative levels of BMI in both childhood and adulthood (P<0.001 for each association). Furthermore, the association between childhood BMI and adult IMT persisted, but was reduced, after controlling for adult BMI. Although childhood levels of lipids, lipoproteins and blood pressure were also associated with adult IMT, these associations were not independent of adult levels of these risk factors. CONCLUSIONS: These results emphasize the adverse effects of elevated childhood BMI levels. In addition to the strong tracking of BMI levels from childhood to adulthood, there appears to be a modest, independent effect of childhood BMI on adult IMT. The prevention of childhood obesity should be emphasized.

Influence of lipoprotein lipase gene Ser447Stop and beta1-adrenergic receptor gene Arg389Gly polymorphisms and their interaction on obesity from childhood to adulthood: the Bogalusa Heart Study.

OBJECTIVE: To investigate the influence of lipoprotein lipase (LPL) Ser447Stop and beta1-adrenergic receptor (ADRB1) Arg389Gly gene polymorphisms, individually and in combination, on obesity from childhood to adulthood. DESIGN AND SUBJECTS: A community-based cohort of 1331 subjects (30% black and 70% white subjects) was followed over an average period of 23 years from childhood (age range: 4-17 years) to adulthood (age range:18-44 years). MEASUREMENT: Body mass index (BMI, kg/m2) and LPL Ser447Stop and the ADRB1 Arg389Gly genotypes. RESULTS: The frequency of the ADRB1 Gly389 allele was 0.25 in white subjects vs 0.39 in black subjects (P < 0.001); 0.08 vs 0.05 (P = 0.280) for the LPL Stop447 allele. There was no association between the LPL Stop447 allele and BMI among white and black subjects either in childhood and adulthood levels or annual change from childhood to adulthood. The ADRB1 Gly389 allele was associated with lower BMI only in black adults (P = 0.017). Further, the interaction effect of the LPL Stop447 allele and ADRB1 Gly389 allele on adult BMI or its annual change was significant in white subjects and in the total sample (P = 0.03-0.006). Childhood values tended to show a similar trend. Having both ADRB1 Gly389 allele and LPL Stop447 allele was associated with 71% (95% confidence interval: 26-89%) less odds for developing obesity from childhood to adulthood after adjusting for age, race, sex, and childhood BMI. CONCLUSION: While Gly389 allele of the ADRB1 gene lowers obesity in black subjects, this allele in conjunction with Stop447 allele of the LPL gene lowers obesity in adults and attenuates the development of obesity from childhood to adulthood. These findings underscore the importance of gene-gene interaction in the assessment of genetic influences on complex traits such as obesity.

Tracking of overweight status from childhood to young adulthood: the Bogalusa Heart Study.

OBJECTIVE: To understand tracking of overweight status from childhood to young adulthood in a biracial sample. DESIGN: A longitudinal sample was created from cross-sectional surveys at two time points, childhood (baseline) and young adulthood (follow-up). SETTING: Bogalusa Heart Study, Louisiana, United States of America. SUBJECTS: A total of 841 young adults, 19-35 years (68% Euro-Americans (EA), 32% African-Americans (AA)) were studied. The same subjects had also participated in one of the five cross-sectional surveys at childhood (9-11 years). METHODS: Body mass index (BMI) was used to determine overweight status as per the Centers for Disease Control and Prevention standards. Change in the BMI status from childhood to young adulthood was used to group the participants into the following categories: normal weight to normal weight (NW-NW); normal weight to overweight (NW-OW); overweight to normal weight (OW-NW); and overweight to overweight (OW-OW). Tracking of overweight was defined by (1) correlations between baseline and follow-up BMI, (2) Cohen's kappa concordance test to determine the strength of tracking in BMI quartiles and (3) the percentage of individuals who remained in the same overweight status group from baseline to follow-up. RESULTS: From baseline to follow-up, the percentage of participants who were overweight increased from 24.7 to 57.7%. A total of 35.2% of the children shifted from normal weight in childhood to overweight in young adulthood (P < 0.0005). Baseline BMI was positively correlated with follow-up BMI (r = 0.66, P < 0.0005). A total of 61.9% of the participants in the highest BMI quartile in childhood remained in the highest BMI quartile in young adulthood. The strength of tracking in BMI quartiles was 27% for EA men (P < 0.0005), 23% for EA women (P < 0.0005), 27% for AA men (P<0.0005) and 35% for AA women (P < 0.0005). A total of 53.7% of the EA women remained in the NW-NW category and 31.2% of the AA women remained in the OW-OW category. The percentage tracking (NW-NW and OW-OW) was 72.8% in EA women, 59.6% in AA men, 59.5% in AA women and 48.8% in EA men (P < 0.0001). CONCLUSION: Childhood overweight tracked into young adulthood in this sample and the tracking of NW-NW and OW-OW was the most prominent among the EA women.

Origins of the "black/white" difference in blood pressure: roles of birth weight, postnatal growth, early blood pressure, and adolescent body size: the Bogalusa heart study.

BACKGROUND: The determinants of differences in blood pressure that emerge in adolescence between black Americans of predominantly African descent and white Americans of predominantly European descent are unknown. One hypothesis is related to intrauterine and early childhood growth. The role of early blood pressure itself is also unclear. We tested whether differences in birth weight and in carefully standardized subsequent measures of weight, height, and blood pressure from 0 to 4 or 5 years were related to black/white differences in blood pressure in adolescence. METHODS AND RESULTS: Two Bogalusa cohorts who had complete follow-up data on birth weights and early childhood and adolescent anthropometric and blood pressure measures were pooled. One hundred eighty-five children (48 black and 47 white boys and 41 black and 49 white girls) were followed up and studied after 15 to 17 years. Birth weights were a mean 443 and 282 g lower in black boys and girls, respectively, than in whites (P<0.001). Blood pressures in adolescence were 3.4/1.9 and 1.7/0.6 mm Hg higher, respectively, and tracked from early childhood. In regression analyses, birth weight accounted for the ethnic difference in adolescent blood pressure, which was also independently predicted, in decreasing impact order, by adolescent height, adolescent body mass index, and systolic blood pressure at 4 to 5 years and inversely by growth from 0 to 4 to 5 years. CONCLUSIONS: If these results can be replicated in larger and independent samples, they suggest that efforts to improve intrauterine growth in black infants as well as lessen weight gain in adolescence might substantially reduce excess high blood pressure/hypertension in this ethnic group.

Cardiovascular risk factors in youth with implications for aging: the Bogalusa Heart Study.

Evidence that cardiovascular (C-V) risk factors are identifiable in childhood and are predictive of future C-V risk is now irrefutable. That levels of C-V risk factors track or persist over time is important, since such phenomenon confers a life-long burden of C-V risk and indicates subtle and progressive changes in the C-V system. C-V risk factors occur often in constellation and central obesity and the attendant insulin resistance/hyperinsulinemia underlie the comorbid conditions of dyslipidemia, hypertension, thrombosis, and inflammation, among others. Autopsy studies and non-invasive subclinical C-V imaging studies in youth clearly link the multiple risk factor burdens to adverse C-V system changes. The application of multiple risk factors profiling in young individuals in conjunction with non-invasive measurements of vascular changes can promote successful aging and encourage preventive cardiology beginning in early life.

Correlates of carotid artery stiffness in young adults: The Bogalusa Heart Study.

Decreased arterial elasticity, an independent risk factor for cardiovascular (C-V) disease, is associated with C-V risk factors in middle-aged and older individuals. However, information is limited in this regard in young adults. This aspect was examined in a community-based sample of 516 black and white subjects aged 25-38 years (71% white, 39% male). The common carotid artery elasticity was measured from M-mode ultrasonography as Peterson's elastic modulus (Ep) and relative wall thickness-adjusted Young's elastic modulus (YEM). Blacks and males had higher Ep (P < 0.05); males had higher YEM (P < 0.0001); and blacks had higher wall thickness (P < 0.01). For the entire sample adjusted for race and gender both Ep and YEM correlated significantly (P < 0.05-0.0001) with age, BMI, waist, systolic and diastolic blood pressures, heart rate, product of heart rate and pulse pressure, triglycerides, total cholesterol to HDL cholesterol ratio, insulin and glucose. In a multivariate regression model that included hemodynamic variables, systolic blood pressure, product of heart rate and pulse pressure, age, triglycerides, BMI, and male gender (for YEM only) were independent correlates of Ep (R2 = 0.38) and YEM (R2 = 0.25). When the hemodynamic variables were excluded from the model, age, triglycerides, BMI, black race (Ep only), male gender, parental history of hypertension, HDL cholesterol (inverse association), and insulin (marginal significance) remained independent correlates of Ep (R2 = 0.20) and YEM (R2 = 16). Both Ep and YEM increased (P for trend P < 0.0001) with increasing number of independent continuous risk factors (defined as values above or below the age, race, and gender-specific extreme quintiles) that were retained in the regression models. The observed increasing arterial stiffness (or decreased elasticity) with increasing number of risk factors related to insulin resistance syndrome in free-living, asymptomatic young adults has important implications for prevention.

An autosomal genome scan for loci influencing longitudinal burden of body mass index from childhood to young adulthood in white sibships: The Bogalusa Heart Study.

OBJECTIVE: To examine genetic loci linked to a long-term burden and trend of obesity traits, such as body mass index (BMI), from childhood to adulthood. DESIGN: : Longitudinal study using serial measurements of BMI from childhood. SUBJECTS: A total of 782 unselected white siblings (representing 521 full and 39 half sib-pairs) from 342 families enrolled in the Bogalusa Heart Study. MEASUREMENTS: A total of 357 microsatellite markers with an average spacing of 9.0 cM spanning the 22 autosomal chromosomes were typed. A quadratic growth curve was developed using a random effects model based on serial measurements of BMI from childhood to adulthood. The serial changes in BMI were measured in terms of long-term burden (area under the curve (AUC) divided by follow-up years) and the long-term trend (incremental AUC, calculated as total AUC-baseline AUC). RESULTS: Heritability estimates of long-term measures were 0.78 for total AUC and 0.43 for incremental AUC. In a variance-component-based multipoint linkage analysis with SOLAR, linkage to the long-term measures of BMI was observed on chromosomes 1, 5, 7, 12, 13 and 18. For total AUC, LOD scores were 3.0 at 110 cM on chromosome 12, 2.9 at 26 cM and 2.4 at 52 cM on chromosome 7, and 2.2 at 126 cM on chromosome 5. For incremental AUC, LOD scores were 2.9 at 26 cM, 2.1 at 97 cM and 2.3 at 110 cM on chromosome 12, 2.2 at 69 cM on chromosome 7, 2.2 at 91 cM and 2.5 at 150 cM on chromosome 1, 2.0 at 119 cM on chromosome 5, 2.0 at 54 cM on chromosome 13 and 2.0 at 7 cM on chromosome 18. Several important obesity-related candidate genes are located in the regions or near the markers showing positive linkage. CONCLUSION: Linkage evidence found in this study indicates that regions on these chromosomes might harbor genetic loci that affect the propensity to develop obesity from childhood.

The relation of obesity throughout life to carotid intima-media thickness in adulthood: the Bogalusa Heart Study.

OBJECTIVE: Although obese children are at increased risk for coronary heart disease in later life, it is not clear if this association results from the persistence of childhood obesity into adulthood. We examined the relation of adiposity at various ages to the carotid intima-media thickness (IMT) at age 35 y. DESIGN: Prior to the determination of IMT by B-mode ultrasound, subjects (203 men, 310 women) had, on average, six measurements of body mass index (BMI) and triceps skinfold thickness (TSF) between the ages of 4 and 35 y. Mixed regression models for longitudinal data were used to assess the relation of these characteristics to adult IMT. RESULTS: Overall, adult IMT was associated with levels of both BMI and TSF (P<0.001), with the magnitudes of the associations with childhood adiposity comparable to those with adult levels of BMI and TSF. Furthermore, adult obesity modified the association between childhood adiposity and IMT: high IMT levels were seen only among overweight (BMI > or =95th percentile) children who became obese (BMI > or =30 kg/m2) adults (P<0.01 for linear trend). In contrast, IMT levels were not elevated among (1) overweight children who were not obese in adulthood, or among (2) thinner children who became obese adults. CONCLUSIONS: These results emphasize the adverse, cumulative effects of childhood-onset obesity that persists into adulthood. Since many overweight children become obese adults, the prevention of childhood obesity should be emphasized.

Inter-relationships among childhood BMI, childhood height, and adult obesity: the Bogalusa Heart Study.

OBJECTIVE: Although the body mass index (BMI, mass index, kg/m2) is widely used as a surrogate measure of adiposity, it is moderately associated (r approximately 0.3) with height among children. We examined whether the resulting preferential classification of taller children as overweight is appropriate. DESIGN: Cross-sectional analyses of children (ages, 3-17 y) examined the relation of height to adiposity (as assessed by BMI and skinfold thicknesses) and fasting levels of insulin. Longitudinal analyses examined the relation of childhood height and weight-height indices to adult (mean age, 25 y) levels of adiposity and fasting insulin. SUBJECTS: Children (n=11,406) and adults (n=2911) who had participated in the Bogalusa Heart Study. MEASUREMENTS: We constructed three weight-height indices: BMI, W/H3, and W/Hp. The triceps and subscapular skinfolds, as well as fasting levels of insulin, were also measured. RESULTS: The classification of children as overweight (BMI-for-age > or =95th percentile) varied markedly by height, with a 10-fold difference in the prevalence of overweight across quintiles of height between the ages of 3 and 10 y. Childhood height, however, was also related to skinfold thicknesses and insulin levels, and all associations were modified in a similar manner by age. Furthermore, childhood height was related to adult adiposity, and of the three childhood weight-height indices, BMI showed the strongest associations with adult adiposity. CONCLUSIONS: Because BMI reflects the positive association between height and adiposity among children, it is a better weight-height index than is either W/H3 or W/Hp.

Longitudinal changes in risk variables underlying metabolic Syndrome X from childhood to young adulthood in female subjects with a history of early menarche: the Bogalusa Heart Study.

OBJECTIVES: To examine the longitudinal changes in adiposity and related risk variables of Syndrome X from childhood to young adulthood with respect to early onset of menarche. DESIGN: Community-based longitudinal cohort of female subject (65% white, 35% blacks subjects) who participated in two or more surveys from childhood to young adulthood and had reported their menarcheal age (<12 y, n=437 vs > or =12 y, n=1042). RESULTS: In childhood (5-11 y), adolescence (12-18 y), and young adulthood (19-37 y), females with early menarche displayed significantly higher body mass index (BMI) and triceps skinfold thickness; higher stature in childhood and adolescence; higher fasting insulin and homeostasis model assessment index of insulin resistance (HOMA-IR) in childhood and adulthood; and higher fasting glucose in adulthood. Blood pressure and lipoprotein variables showed no early menarche-related differences. Longitudinal rates of change in BMI (P=0.002), triceps skinfold thickness (P=0.05), insulin (P=0.09), and HOMA-IR (P=0.05) were positive and faster among female subjects with early menarche; fasting glucose decreased slowly in this group (P=0.006). In a multivariate analysis, body fatness and insulin related independently to early menarche (P<0.001). This association was stronger in white subjects (P=0.0008). In adulthood, the prevalence of clustering of three to four risk factors of syndrome X (highest quartile of: (1) BMI, (2) fasting insulin, (3) systolic or mean arterial pressure, and (4) total cholesterol to HDL cholesterol or triglycerides to HDL cholesterol ratio specific for age, race, and study year) was higher among those with early menarche (10.7 vs 6.2%, P=0.002). The odds for developing such clustering in adulthood among those with early menarche was 1.54 (95% CI=1.14-2.07), regardless of race. CONCLUSION: Early menarche is characterized by excess body fatness and insulin beginning in early childhood and higher prevalence of clustering of adverse levels of risk variables of metabolic Syndrome X in young adulthood.

Differences in body shape representations among young adults from a biracial (Black-White), semirural community: the Bogalusa Heart Study.

In this study, the authors examined body image perception and body mass index (weight (kg)/height (m)(2)) among race-gender groups in a biracial (Black-White) population of young adults in Bogalusa, Louisiana. A mail-out survey was completed in 1994 by 3,698 (65%) participants aged 18.5-35 years in the Bogalusa Heart Study (mean age = 27.6 years). As part of the survey, body image perception was determined in terms of body shape representations from a figure rating scale. A body image discrepancy score was calculated from the difference between z-standardized values of body image perception and body mass index. A stepwise proportional odds model including the covariates income, employment, education, and physical activity was used to identify factors influencing lower perception of body shape. Mean body mass index was highest among Black females (p < 0.001). The odds of having a lower perception of body shape (vs. body mass index) were 1.72 times higher in Blacks (p < 0.001), 0.80 times lower in persons who were currently employed (p < 0.001), and 0.86 times lower in persons with a higher education (p = 0.032). Gender, income, and physical activity were not found to be significant predictors of body image perception (p > 0.05). The authors conclude that significant differences exist within racial groups concerning body image perception in relation to overweight status among young adults. This has implications for prevention and education programs.

Influence of the beta2-adrenergic receptor Arg16Gly polymorphism on longitudinal changes in obesity from childhood through young adulthood in a biracial cohort: the Bogalusa Heart Study.

BACKGROUND: The beta2-adrenergic receptor (ADRB2) plays a major role in regulating energy expenditure by stimulating lipid metabolism in human adipose tissue. Polymorphisms in the ADRB2 gene have been associated with obesity and various weight-related traits in cross-sectional studies of adults, but little is known about the effects of the ADRB2 gene on childhood obesity or the propensity to gain weight over time. OBJECTIVE: To assess the effects of a polymorphism in codon 16 (Arg16-->Gly) of the ADRB2 gene, which has been associated with a decrease in beta2-receptor density and efficiency, on longitudinal changes in obesity from childhood to young adulthood in a biracial cohort. DESIGN: Seven cross-sectional screenings of children and five cross-sectional screenings of young adults who were previously examined as children produced longitudinal data from childhood to young adulthood. METHODS: Height, weight and subscapular and triceps skinfolds were measured by trained examiners following identical protocols over the course of the study. Gender- and age-stratified analyses using random coefficients models were used to examine longitudinal genetic effects on obesity in 1151 African-American and Caucasian males and females who attended an average of six examinations over a 24 y period from childhood to young adulthood. RESULTS: Age-stratified analyses showed no clear genetic relationships with changes in obesity measures over time in females, but an age-dependent association was observed in males, where the relationship between the Arg16Gly polymorphism and obesity became stronger with age. In males who were 4-9 y of age at the beginning of the study in 1973, body mass index (BMI) was 4% higher in Gly/Gly and Arg/Gly males compared to those with Arg/Arg by 26 y of age. Subscapular skinfold measurements in Gly/Gly males became significantly different from Arg/Arg males (20% higher) by age 20. In the oldest male cohort (10-14 y of age in 1973), BMI increased at a significantly greater rate (0.4%/y) in males carrying the Gly16 form of the receptor relative to Arg/Arg males. BMI was significantly different between homozygous genotypes by approximately 26 y of age, and reached 8% higher in Gly/Gly males by age 32. Subscapular skinfolds also increased at a significantly greater rate (2%/y) in Gly/Gly males compared to Arg/Arg males, becoming significantly different (27%) by approximately 22 y of age and reaching a maximum difference of 50% by age 32. CONCLUSIONS: Our data suggest that the beta2-adrenergic receptor is associated with the propensity to gain weight from childhood to young adulthood in males. An increased understanding of genetic influences on the development of obesity may improve the effectiveness of interventions designed to reduce excess body weight and help define the role of genetic factors in diabetes and cardiovascular disease.

Tracking of serum lipids and lipoproteins from childhood to dyslipidemia in adults: the Bogalusa Heart Study.

Our data demonstrate that serum lipid and lipoprotein levels continue to track from childhood into young adulthood. The persistence and clustering of multiple CVD risk factors from childhood to adulthood and the impact of obesity in this regard point to the need for preventive measures aimed at developing healthy lifestyles early in life. Adverse levels of LDL-C in childhood persist over time, progress to adult dyslipidemias, and relate to obesity and hypertension as well. NCEP guidelines which classify CVD risk on the basis of LDL-C level, are helpful in targeting individuals at risk early in life.

Trends of lipoprotein variables from childhood to adulthood in offspring of parents with coronary heart disease: the Bogalusa Heart Study.

Although dyslipidemia among offspring of parents with coronary heart disease (CHD) has been known, the development of this adverse relationship with respect to specific lipoprotein variables from childhood to young adulthood has not been elucidated. This aspect was examined in a young adult cohort with (n = 271) and without (n = 805) a parental history of CHD followed longitudinally since childhood by repeated surveys from 1973 to 1991. Trends in fasting lipoprotein variables by parental CHD status were assessed by Lowess smoothing curve and Generalized Estimating Equations (GEE). In multivariate analyses adjusted for race and sex, parental CHD associated positively with low-density lipoprotein cholesterol (LDL-C, P <.01) and triglycerides (P <.05) mainly at the young adulthood age, whereas a positive association was noted with very-low-density lipoprotein cholesterol (VLDL-C) during both childhood and young adulthood (P <.05). The positive association between parental CHD and LDL-C in young adulthood persisted independently of body mass index (BMI) and fasting insulin, but disappeared when fasting glucose was added to the model. With respect to triglycerides and VLDL-C, inclusion of BMI, insulin, and/or glucose eliminated the adverse association with parental CHD. These observations suggest that parental CHD is just one more explanatory variable that loses its partial contribution to lipoprotein profiles in their offspring when other strongly interrelated contributory variables such as age, body fatness, and measures of glucose homeostasis are taken into account. Information on these risk variables in conjunction with parental or family history of CHD may enhance the potential of CHD risk assessment in youth.