Racial divergence in adiposity during adolescence: The NHLBI Growth and Health Study

Childhood adversity and accelerated reproductive events: a systematic review and meta-analysis

OBJECTIVE

Accelerated female reproductive events represent the early onset of reproductive events involving puberty, menarche, pregnancy loss, first sexual intercourse, first birth, parity, and menopause. This study aimed to explore the association between childhood adversity and accelerated female reproductive events.

DATA SOURCES

PubMed, Web of Science, and Embase were systematically searched from September 22, 2022 to September 23, 2022.

STUDY ELIGIBILITY CRITERIA

Observational cohort, cross-sectional, and case-control studies in human populations were included if they reported the time of reproductive events for female individuals with experience of childhood adversity and were published in English.

METHODS

Two reviewers independently screened studies, obtained data, and assessed study quality, and conflicts were resolved by a third reviewer. Dichotomous outcomes were evaluated using meta-analysis, and pooled odds ratios and 95% confidence intervals were generated using random-effects models. Moderation analysis and meta-regression were used to investigate heterogeneity.

RESULTS

In total, 21 cohort studies, 9 cross-sectional studies, and 3 case-control studies were identified. Overall, female individuals with childhood adversity were nearly 2 times more likely to report accelerated reproductive events than those with no adversity exposure (odds ratio, 1.91; 95% confidence interval, 1.33-2.76; I2=99.6%; P<.001). Moderation analysis indicated that effect sizes for the types of childhood adversity ranged from an odds ratio of 1.61 (95% confidence interval, 1.23-2.09) for low socioeconomic status to 2.13 (95% confidence interval, 1.14-3.99) for dysfunctional family dynamics. Among the 7 groups based on different reproductive events, including early onset of puberty, early menarche, early sexual initiation, teenage childbirth, preterm birth, pregnancy loss, and early menopause, early sexual initiation had a nonsignificant correlation with childhood adversity (odds ratio, 2.70; 95% confidence interval, 0.88-8.30; I2=99.9%; P<.001). Considerable heterogeneity (I2>75%) between estimates was observed for over half of the outcomes. Age, study type, and method of data collection could explain 35.9% of the variance.

CONCLUSION

The literature tentatively corroborates that female individuals who reported adverse events in childhood are more likely to experience accelerated reproductive events. This association is especially strong for exposure to abuse and dysfunctional family dynamics. However, the heterogeneity among studies was high, requiring caution in interpreting the findings and highlighting the need for further evaluation of the types and timing of childhood events that influence accelerated female reproductive events.

Cohort profile: the longitudinal National Growth and Health Study (NGHS) of black and white girls from Northern California tracking how behavioural and psychosocial risk factors predict cardiovascular risk and biological ageing in midlife and in offspring

PURPOSE

The National Heart, Lung and Blood Institute Growth and Health Study (NGHS) prospectively collected anthropometric, biospecimens, clinical, health behaviour and psychosocial measures associated with cardiovascular disease from childhood to young adulthood. The aim of the current study was to assess the impact of stress, dysregulated eating and social genomic biomarkers on cardiometabolic risk factors among the original participants now in midlife and their children.

PARTICIPANTS

Beginning in 1987-1988, NGHS recruited black and white girls (age 9-10 years) from socioeconomically diverse backgrounds from from three sites: Cincinnati, Ohio; Washington, DC; and Western Contra Costa County, California (N=2379) and followed them for 10 years. The study maintained an 89% retention rate. The current study is 30 years after the start of the original study and focused on the participants of California (n=887) and their children aged 2-17 years. We re-enrolled 624 of 852 eligible participants (73%): 49.2% black and 50.8% white. The mean age was 39.5 years. Among the 645 eligible biological children, 553 were enrolled; 49% black and 51% white, with 51.5% girls and 48.5% boys. The mean age was 9.3 years.

FINDINGS TO DATE

Longitudinal analysis of adolescent drive for thinness predicted higher scores for drive for thinness during midlife, which was indirectly associated with greater adult body mass index through adult drive for thinness. Latent trajectory modelling of adolescent growth over 10 years found that women with persistently high weight trajectory had twice the odds of having children who met the definition for obesity compared with the persistently normal group, adjusting for adult weight.

FUTURE PLANS

New studies on neighbourhood socioeconomic status, food insecurity and additional biomarkers of chronic stress, microbiome and accelerated ageing (ie, telomere length and epigenetic clock) are underway. We are developing a 10-year follow-up to understand changes in ageing biomarkers of the participants and their children.

TRIAL REGISTRATION NUMBER

NCT00005132.

LAPAROSCOPIC BARIATRIC SURGERY IN ADOLESCENTS: EARLY AND FIVE- YEAR CLINICAL AND LABORATORY ASSESSMENT

BACKGROUND

Obesity has reached epidemic proportions among adolescents. Methods, such as bariatric surgery, have become the most effective treatment for patients with classes III and IV obesity.

AIM

To evaluate weight loss, comorbidity remission, and long-term results of bariatric surgery in adolescents.

METHODS

Study with adolescent patients undergoing bariatric surgery, evaluating laboratory tests, comorbidities, and the percentage of excess weight loss in the preoperative period and at one, two, and five years postoperatively.

RESULTS

A total of 65 patients who met the inclusion criteria, with a mean age of 18.6 years, were included in the analysis. In the preoperative period, 30.8% of hypercholesterolemia, 23.1% of systemic arterial hypertension, and 18.4% of type 2 diabetes were recorded, with remission of these percentages occurring in 60, 66.7 and 83.4%, respectively. The mean percentage of excess weight loss was 63.48% after one year of surgery, 64.75% after two years, and 57.28% after five years. The mean preoperative total cholesterol level was 180.26 mg/dL, and after one, two, and five years, it was 156.89 mg/dL, 161.39 mg/dL, and 150.97 mg/dL, respectively. The initial mean of low-density lipoprotein was 102.19mg/dL and after five years the mean value reduced to 81.81 mg/dL. The mean preoperative glycemia was 85.08 mg/dL and reduced to 79.13 mg/dL after one year, and to 76.19 mg/dL after five years.

CONCLUSIONS

Bariatric surgery is safe and effective in adolescents, with low morbidity, resulting in a loss of excess weight and long-term stability, improving laboratory tests, and leading to remission of comorbidities, such as diabetes mellitus, hypercholesterolemia, and systemic arterial hypertension.

Association of body composition with pubertal timing in children and adolescents from Guangzhou, China

Objective

An ongoing debate surrounds the relationship between body composition and pubertal timing, in particular for boys. This cross-sectional study aimed to investigate the association of body composition with pubertal timing among children and adolescents.

Methods

A total of 1,493 boys and 1,261 girls who entered puberty were enrolled in Guangzhou, China. Tanner stages were evaluated by examination of breast development for girls and testicular volume for boys. Fat mass (FM) and fat-free mass (FFM) were determined by bioelectrical impedance analysis. Parameters for body composition were transformed into age-and gender-specific Z-scores. The association of body composition with pubertal timing was examined using multinomial logistic regression with inverse probability weighting (IPW) based on the propensity score.

Results

For boys, IPW analysis showed Z-scores of body fat percentage (BF%) and FM index (FMI) were negatively associated with early puberty (OR = 0.75, 95% CI = 0.64-0.87; OR = 0.74, 95% CI = 0.63-0.88). As for girls, in contrast to boys, positive associations were seen between BF% and FMI with early puberty (OR = 1.39, 95% CI = 1.19-1.64; OR = 1.59, 95% CI = 1.33-1.90). With respect to appendicular skeletal muscle mass index (ASMI), there was a positive association with early puberty and a negative one with late puberty in boys (OR = 1.26, 95% CI = 1.07-1.49; OR = 0.82, 95% CI = 0.69-0.99).

Conclusion

There is a positive association of FM with early puberty for girls while negative for boys. FFM yields a positive association with early puberty and a negative one with late puberty in boys, but not in girls. Our findings highlight the gender differences in the connection between body composition and pubertal onset.

Visceral, subcutaneous, and total fat mass accumulation in a prospective cohort of adolescents

BACKGROUND

Race and sex differences in adolescents' body fat are demonstrated in cross-sectional cohorts, yet a longitudinal design would better identify patterns of fat distribution over time.

OBJECTIVES

The aim was to examine race and sex differences in adiposity between black and white adolescents over 2 y.

METHODS

A cohort of adolescents aged 10-16 y (38% black; 52% girls; 15% overweight, 34% with obesity) underwent body composition measurements at baseline (n = 309) and 2 y later (n = 236), using DXA to quantify whole-body fat mass (FM) and MRI for abdominal subcutaneous (SAT) and visceral adipose tissue (VAT) volumes. General linear models were used to examine race and sex differences in log-transformed FM, SAT, and VAT, adjusting for age, sexual maturation, extended BMI percentile, and race-by-sex interaction. SAT and VAT models in addition controlled for baseline FM and change in FM (for change models).

RESULTS

Mean (95% CI) baseline FM (kg) was higher among white [18.5 (17.9, 19.2) than among black adolescents [17.4 (16.6, 18.2), P = 0.03] and girls [19.5 (18.8, 20.3) than boys [16.5 (15.8, 17.2), P < 0.0001]. Mean (95% CI) baseline SAT (L) was higher among girls [4.4 (4.2, 4.6)] than among boys [3.9 (3.7, 4.1), P < 0.0001]. Mean (95% CI) baseline VAT (L) was higher among white [0.5 (0.5, 0.6)] than among black [0.3 (0.3, 0.4)] adolescents (P < 0.0001) and boys [0.5 (0.4, 0.5)] than girls [0.4 (0.4, 0.4), P = 0.04]. Over 2 y mean (95% CI) FM change (kg) was higher among white [3.7 (2.9, 4.5)] than among black adolescents [2.3 (1.3, 3.3), P = 0.04] and girls [4.0 (3.0, 4.9)] than boys [2.0 (1.1, 3.0), P = 0.007], but SAT change (L) did not differ by race or sex. VAT change (L) was higher among white [0.1 (0.1, 0.1)] than among black adolescents [0.0 (0.0, 0.1), P = 0.003] and boys [0.1 (0.1, 0.1)] than girls [0.0 (0.0, 0.1), P = 0.034].

CONCLUSIONS

Sex and race differences in the deposition and accumulation of excess fat are important considerations for understanding obesity prevalence and obesity-related disease risk among adolescents.This trial was registered at clinicaltrials.gov as NCT02784509.

Effects of Early Life Adversity on Pubertal Timing and Tempo in Black and White Girls: The National Growth and Health Study

OBJECTIVE

Although exposure to abuse in early life predicts earlier pubertal timing, especially for girls, it is unclear if this association generalizes to nonabuse stressors. In addition, the impact of race on the stress-maturation association remains unknown. To address these issues, we examined whether race moderates the effects of early adversity on pubertal timing and tempo using a longitudinal study design.

METHODS

In a cohort of 9- and 10-year-old Black and White girls, pubertal (areolar and pubic hair) maturation was assessed annually for 7 years. In adulthood, 368 participants (186 Black, 182 White) reported on abuse and nonabuse stressors they experienced from ages 0 to 12 years.

RESULTS

Early life abuse was associated with earlier pubertal timing, as indexed by younger age at menarche (b = -0.22, p = .005, 95% confidence interval [CI] = -0.39 to -0.06) and greater pubic hair development (b = 0.11, p = .003, 95% CI = 0.04 to 0.18), in addition to slower pubertal tempo, as indexed by slower rate of pubic hair (b = -0.03, p < .001, 95% CI = -0.05 to -0.01) and areolar (b = -0.02, p = .02, 95% CI = -0.03 to -0.003) development. These associations were not found for nonabuse adversity. Black girls with early life abuse had greater pubic hair development (b = 0.23, p < .001, 95% CI = 0.12 to 0.35) and were slower in pubic hair tempo (b = -0.07, p < .001, 95% CI = -0.09 to -0.04) than their White counterparts.

CONCLUSIONS

Screening for early life abuse may help address health disparities related to earlier pubertal timing.

Salt Sensitivity of Blood Pressure in Blacks and Women: A Role of Inflammation, Oxidative Stress, and Epithelial Na+ Channel

Significance: Salt sensitivity of blood pressure (SSBP) is an independent risk factor for mortality and morbidity due to cardiovascular disease, and disproportionately affects blacks and women. Several mechanisms have been proposed, including exaggerated activation of sodium transporters in the kidney leading to salt retention and water. Recent Advances: Recent studies have found that in addition to the renal epithelium, myeloid immune cells can sense sodium via the epithelial Na⁺ channel (ENaC), which leads to activation of the nicotinamide adenine dinucleotide phosphate oxidase enzyme complex, increased fatty acid oxidation, and production of isolevuglandins (IsoLGs). IsoLGs are immunogenic and contribute to salt-induced hypertension. In addition, aldosterone-mediated activation of ENaC has been attributed to the increased SSBP in women. The goal of this review is to highlight mechanisms contributing to SSBP in blacks and women, including, but not limited to increased activation of ENaC, fatty acid oxidation, and inflammation. Critical Issues: A critical barrier to progress in management of SSBP is that its diagnosis is not feasible in the clinic and is limited to expensive and laborious research protocols, which makes it difficult to investigate. Yet without understanding the underlying mechanisms, this important risk factor remains without treatment. Future Directions: Further studies are needed to understand the mechanisms that contribute to differential blood pressure responses to dietary salt and find feasible diagnostic tools. This is extremely important and may go a long way in mitigating the racial and sex disparities in cardiovascular outcomes. Antioxid. Redox Signal. 35, 1477-1493.

Cardiovascular health decline in adolescent girls in the NGHS cohort, 1987-1997

Adolescence is a critical time for the preservation or loss of cardiovascular health. We aimed to describe trajectories of cardiovascular health in adolescent girls and identify early adolescent factors associated with cardiovascular health in young adulthood. We used data from the National Growth and Health Study, a longitudinal cohort of 2,379 girls followed annually from ages 9-19 years. We classified participants as having ideal, intermediate, or poor levels of the seven cardiovascular health metrics at four developmental stages: early (ages 9-11), middle (ages 12-14), and late (ages 15-17) adolescence, and early young adulthood (ages ≥ 18). We calculated total cardiovascular health scores (range 0-14) at each stage and empirically identified patterns of cardiovascular health trajectories. We examined associations between trajectory group membership and various demographic, behavioral, and physiological factors. Mean cardiovascular health scores declined with age from 10.8 to 9.4 in white girls and 10.3 to 8.9 in black girls; 17% of white girls and 23% of black girls had low cardiovascular health (score < 8) by early young adulthood. We identified five cardiovascular health trajectories: high-stable (14% of participants), high-to-moderate (48%), high-to-low (20%), moderate-stable (10%), and moderate-to-low (8%). Exceeding 14 h per week of television in early adolescence and teen pregnancy were associated with higher odds of being in several less healthy trajectory groups. In conclusion, cardiovascular health declines during adolescence and black-white disparities begin before early adolescence. Key targets for improving cardiovascular health in adolescent girls may include reductions in sedentary behavior and prevention of teen pregnancy.

Novel ranking of protective and risk factors for adolescent adiposity in US females

OBJECTIVE

Rank the importance of potentially modifiable psychosocial, dietary and environmental risk and protective factors for female adolescent obesity in order to target and inform public health prevention efforts. Utilizing the largest dataset available that captures the onset of the adolescent obesity surge in the USA, the study provides a more robust understanding of paediatric obesity risk factors.

METHODS

Data were obtained from an observational, longitudinal study conducted between 1989 and 2001, the NHLBI Growth and Health Study. This study includes girls aged 9-19 years from three urban US locations, with Black and White girls generally represented equally. Data were analysed using multiple regression, random forest and propensity score matching to determine the strongest adiposity risk and protective factors during ages 9-12 predicting adiposity at age 19 with multiple methods to maximize the ability to identify possible public health interventions. Multiple linear regression and random forest analysis identified the strongest associations among 288 risk and protective factors selected from the study's literature review. For the 190 factors associated with follow-up adiposity from the data, propensity score matching was used to control for confounding of these factors.

RESULTS

Findings suggest that highest priority interventional targets across the domains surveyed are lowering specific nutrients; eating meals with others or during activities without skipping; parents fixing evening snacks; improving perceptions of non-extremes as the healthy weight; improving self-worth, physical activity and social competence; and limiting any negative impact of dieting relatives. Similar associations were observed for Black and White girls.

CONCLUSION

The clinical implications of these findings allow health practitioners to target behavioural change efforts and address social and environmental factors that have demonstrated higher prioritization value for early obesity interventional efforts for adolescents.

Fitness adjusted racial disparities in central adiposity among women in the USA using quantile regression

OBJECTIVE

This study comprehensively explores racial/ethnic disparities in waist circumference (WC) after adjusting for cardiorespiratory fitness (CRF), among both adult and adolescent women, across WC percentiles.

METHODS

Analysis was conducted using data from the 1999 to 2004 National Health and Nutrition Examination Survey. Female participants (n = 3,977) aged 12-49 years with complete data on CRF, height, weight and WC were included. Quantile regression models, stratified by age groups (12-15, 16-19 and 20-49 years), were used to assess the association between WC and race/ethnicity adjusting for CRF, height and age across WC percentiles (10th, 25th, 50th, 75th, 90th and 95th).

RESULTS

For non-Hispanic (NH) Black, in both the 16-19 and 20-49 years age groups, estimated WC was significantly greater than for NH White across percentiles above the median with estimates ranging from 5.2 to 11.5 cm. For Mexican Americans, in all age groups, estimated WC tended to be significantly greater than for NH White particularly for middle percentiles (50th and 75th) with point estimates ranging from 1.9 to 8.4 cm.

CONCLUSIONS

Significant disparities in WC between NH Black and Mexican women, as compared to NH White, remain even after adjustment for CRF. The magnitude of the disparities associated with race/ethnicity differs across WC percentiles and age groups.

Factors related to obesity and overweight among Black adolescent girls in the United States

In the United States, Black adolescents have the highest prevalence of pediatric obesity and overweight among girls. While Black girls are disproportionately affected, the reasons for this health disparity remain unclear. The authors conducted a systematic review to investigate the factors related to obesity and overweight among Black adolescent girls. The authors searched four databases for relevant English-language publications using all publication years through 2015. Fifty-one studies met the inclusion criteria and were used for this review. Using a configuration approach to synthesis, three categories were identified, paralleling the bioecological theory of human development: (1) individual, (2) interpersonal, and (3) community and societal factors. A description of each factor's association with obesity among Black adolescent girls is presented. From this review, the authors identified a diverse and vast set of individual, interpersonal, and community and societal factors explored for their relationship with obesity and overweight. Given the insufficient repetition and limited significant findings among most factors, the authors believe that multiple gaps in knowledge exist across all categories regarding the factors related to obesity and overweight among Black adolescent girls. To improve the quality of research in this area, suggested research directions and methodological recommendations are provided.

Disparities in the Context of Opportunities for Cancer Prevention in Early Life

Persistent health disparities are a major contributor to disproportionate burden of cancer for some populations. Health disparities in cancer incidence and mortality may reflect differences in exposures to risk factors early in life. Understanding the distribution of exposures to early life risk and protective factors for cancer across different populations can shed light on opportunities to promote health equity at earlier developmental stages. Disparities may differentially influence risk for cancer during early life and create opportunities to promote health equity. Potential risk and protective factors for cancer in early life reveal patterns of disparities in their exposure. These disparities in exposures can manifest in downstream disparities in risk for cancer. These risk and protective factors include adverse childhood experiences; maternal alcohol consumption in pregnancy; childhood obesity; high or low birth weight; benzene exposure; use of assisted reproductive technologies; pesticide and insecticide exposure; isolated cryptorchidism; early pubertal timing; exposure to radiation; exposure to tobacco in utero and in early life; allergies, asthma, and atopy; and early exposure to infection. Disparities on the basis of racial and ethnic minority status, economic disadvantage, disability status, sex, geography, and nation of origin can occur in these risk and protective factors. Vulnerable populations experience disproportionally greater exposure to risk factors in early life. Addressing disparities in risk factors in early life can advance opportunities for prevention, promote health equity, and possibly reduce risk for subsequent development of cancer.

Trends in Early Childhood Obesity in a Large Urban School District in the Southwestern United States, 2007-2014

INTRODUCTION

Although recent studies indicate that rates of childhood obesity and severe obesity may be declining, few studies have reported prevalence trends in early childhood or differences in trends across sociodemographic groups. The primary aim of this study was to report trends in prevalence of early childhood obesity and severe obesity 2007 through 2014 in a diverse, metropolitan school district in the southwestern United States and determine whether these trends vary by race/ethnicity, socioeconomic status, and disability status.

METHODS

We analyzed height, weight and demographic data from 43,113 kindergarteners enrolled in a large, urban school district in the southwestern United States for 7 school years. Adjusted odds of obesity and severe obesity were calculated to assess changes in prevalence for non-Hispanic white, Hispanic, and American Indian students; free or reduced-price lunch participants and nonparticipants; and students with and without disabilities. To test for differences in obesity trends, interaction terms were added to the logistic regressions between school year and sex, race/ethnicity, free or reduced-price lunch participation, and disability status.

RESULTS

The adjusted prevalence of both obesity (from 13.1% in 2007-2008 to 12.0% in 2013-20014) and severe obesity (from 2.4% in 2007-2008 to 1.2% in 2013-2014) declined overall. We found no significant interactions between the adjusted prevalence of obesity over time and any of the sociodemographic subgroups. Obesity prevalence declined more among American Indian students than among Hispanic or non-Hispanic white students.

CONCLUSION

In this district, from 2007 through 2014, severe obesity decreased and obesity did not increase, overall and across all sociodemographic subpopulations for kindergarten students.

Cardiorespiratory fitness in urban adolescent girls: associations with race and pubertal status

Cardiorespiratory fitness affords health benefits to youth. Among females, weight-relative fitness declines during puberty and is lower among African American (AA) than Caucasian girls. Data indicate racial differences in pubertal timing and tempo, yet the interactive influence of puberty and race on fitness, and the role of physical activity (PA) in these associations have not been examined. Thus, independent and interactive associations of race and pubertal development with fitness in adolescent girls, controlling for PA were examined. Girls in grades 5-8 (n = 1011; Caucasian = 25.2%, AA = 52.3%, Other Race group = 22.5%) completed the Pubertal Development Scale (pubertal stage assessment) and Fitnessgram® Progressive Aerobic Cardiovascular Endurance Run (PACER) test (cardiorespiratory fitness assessment). PA was assessed by accelerometry. Bivariate and multivariate analyses were used to examine associations among race, pubertal stage and fitness, controlling for vigorous PA, AA, and pubertally advanced girls demonstrated lower fitness than Caucasian and less mature counterparts. Puberty and race remained significantly associated with fitness after controlling for vigorous PA. The interaction effect of race and puberty on fitness was non-significant. The pubertal influence on fitness is observed among AA adolescents. Associations between fitness and race/puberty appear to be independent of each other and vigorous PA. Pubertally advanced AA girls represent a priority group for fitness interventions.

The obesity epidemic in children: Latino children are disproportionately affected at younger ages

Background and objectives

National surveillance clearly illustrates that U.S. children are becoming increasingly overweight. However, the timing of the onset of childhood overweight has not been well-described.

Patients and methods

An accelerated failure time (AFT) model was used to describe the emergence of overweight based on a 12-year collection of height and weight data of over 40,000 children. Race, sex, insurance status and their interactions were specifically examined as predictors of earlier onset of overweight. The outcome of interest was an estimate of the age at which the model predicted that a subgroup would attain a 20% prevalence of overweight.

Results

The three-way interaction of race, sex, and insurance status was a significant predictor of onset of overweight. The model estimated that the publicly insured Latino male subgroup had the earliest onset of overweight, attaining a prevalence of 20% overweight by 4.3 years of age. The emergence of overweight in Latino subjects was significantly earlier than that for black or white subjects, irrespective of sex or insurance status.

Conclusion

Regardless of sex or insurance status, overweight emerges at significantly younger ages in Latino children when compared to black and white children. Substantial numbers of Latino male children are predicted to develop overweight at preschool ages. Obesity prevention may need to be directed toward parents or children well before children enter grade-school.

Adolescent oligomenorrhea (age 14-19) tracks into the third decade of life (age 20-28) and predicts increased cardiovascular risk factors and metabolic syndrome

OBJECTIVE

Assess whether adolescent oligomenorrhea (age 14-19) tracks into young adulthood (age 20-28) and predicts increased cardiometabolic risk factors, metabolic syndrome (MetS), and impaired fasting glucose-type II diabetes mellitus (IFG+T2DM).

MATERIALS AND METHODS

Prospective study of menstrual cyclicity and its metabolic effects in 865 black and white schoolgirls from age 9 to 19, and 605 of these 865 girls from age 20 to 28.

MAIN FINDINGS

Patterns of menstrual delays (oligomenorrhea) during ages 14-19 and ages 20-28 were closely related (p<.0001). Adolescent menses delay (ages 14-19, p<.0001), mean insulin (ages 20-28, p=.0003), and self-identified polycystic ovary syndrome (PCOS, p=.049) predicted ages 20-28 menses delay. Menses delays during ages 14-19 and 20-28, and, their interaction product were correlated with IFG+T2DM and MetS at ages 20-28. Waist circumference (ages 20-28, p<.0001), mean triglyceride (ages 20-28, p=.005), and the number of average menstrual cycles≥42 days (ages 20-28, p=.04) predicted IFG+T2DM (ages 20-28). MetS (ages 9-19, p<.0001), mean insulin (ages 20-28, p=.0002), the number of ≥42 day gaps between menstrual periods (ages 20-28, p=.02), and cigarette smoking at age 18-19 (p=.04) were significant explanatory variables for MetS at ages 27-28. As MetS status category changed from age 14-19 to 27-28 from best to worst: (no → no), (yes → no), (yes → yes), (no → yes), the number of women with ≥2 menses delays during ages 20-28 rose from 3% to 4% to 15% to 17%, p=.0001. MetS status change from age 9-19 to 27-28 was positively associated with mean insulin (age 20-28, p<.0001), cigarette smoking (age 24-25, p=.01) and the number of menses delays during ages 20-28 (p=.04).

PRINCIPAL CONCLUSIONS

Menstrual patterns track from adolescence to young adulthood, and oligomenorrhea predicts MetS and IFG+T2DM. Patterns of menses delays in adolescence should be considered as a significant risk factor for future development of young adult IFG+T2DM, MetS, oligomenorrhea, and polycystic ovary syndrome.

Adolescent and young adult female determinants of visceral adipose tissue at ages 26-28 years

OBJECTIVE

To assess adolescent and young adult determinants of visceral adipose tissue (VAT) at ages 26-28 years.

STUDY DESIGN

Prospective study (ages 9-28 years) of cardiometabolic measures, menarche age, menses irregularities, metabolic syndrome, impaired fasting glucose-type 2 diabetes mellitus, and VAT in 400 girls (248 black, 152 white).

RESULTS

Adolescent (age 14-19) independent variables for greater VAT at ages 26-28 included larger mean waist circumference (partial R(2) = 30.8%), earlier age at menarche (0.9%), and white race (1.8%). Young adult (ages 20-28 years) independent variables for greater VAT included larger mean waist circumference (partial R(2) = 61.7%), greater triglyceride levels (3.3%), lower high-density lipoprotein cholesterol (1.0%), and greater insulin resistance (homeostasis model assessment-estimated insulin resistance; 0.4%). Independent variables for greater VAT when both adolescent and young adult variables were used included waist (tertile rank change from adolescence to young adulthood, partial R(2) = 58.3%), greater young adult triglyceride levels (4.4%), white race (1.8%), greater young adult homeostasis model assessment-estimated insulin resistance (age 20-28, 2.4%), and earlier menarche age (0.7%). Menses irregularities were not independently associated with young adult VAT.

CONCLUSIONS

Adolescent girls with early menarche and larger waist circumference should be targets for primary prevention of accretion of VAT. In young adulthood, VAT is associated with dysregulated cardiometabolic profiles, which is greater for those with waist circumference increases from adolescence to adulthood. Waist circumference during young adulthood, and to a lesser degree during adolescence, is an inexpensive surrogate for VAT at ages 26-28 years.

Risk Factors Associated with Overweight among Adolescents in Serbia

INTRODUCTION

The pandemic of obesity in adolescents is one of the challenges of public health.

AIM

The aim of this study was to examine the association of overweight with demographic, socioeconomic and lifestyle factors among Serbian adolescents.

METHOD

A cross-sectional study of 2139 adolescents aged 10 to 19 years was carried out. Data used in this study were from the 2006 Health Survey. In accordance with the international sex- and age-specific Body Mass Index cut-off points, all participants were classified as being normal weight or overweight, including obese. The association between the risk factors and overweight were examined using a multivariate logistic regression model.

RESULTS

The study showed that 28.9% of boys and 17.0% of girls were overweight, while 14.5% of boys and 8.1% of girls were obese. Boys were more likely to be overweight/obese, compared with girls. Being younger (p< 0.01 for 14 to 15 years) and (p< 0.01, for 16 to 19 years), engaging in physical activities that last less than 7 hours a week, in such a manner that they breathe quickly and become sweaty, (p< 0.01) and skipping breakfast (p< 0.05) were risk factors significantly associated with overweight among adolescents. No significant association was found with wealth index.

CONCLUSION

These findings should be an integral part of further preventive interventions, especially oriented towards younger adolescents, who are physically inactive, have a habit of skipping breakfast and are boys.

Younger pubertal age is associated with allergy and other atopic conditions in girls

BACKGROUND

Early menarche is linked to higher incidence of adult asthma, suggesting that earlier puberty may influence type 2 immune response characteristics of allergic diseases. We examined the hypothesis that timing of breast and pubic hair development, which precede menarche, is associated with increased childhood atopic conditions.

METHODS

Girls were enrolled at 6-8 yr of age (2004-2007) in the Breast Cancer and the Environment Research Program Puberty Study and were followed through 2011. Pubertal stages were assessed and atopic conditions were queried annually. Associations of age at pubertal stage 2 for breast or pubic hair development with atopic conditions were assessed using prevalence ratios (PR) or odds ratios (OR) and 95% confidence intervals (CI) from log-binomial regression and generalized estimating equation models, controlling for body mass index and other covariates. A total of 1055 girls with medical and pubertal stage data were included.

RESULTS

Asthma (ever vs. never) was associated with younger pubarche (≤10 vs. >10 yr, PR = 1.15, CI: 1.04-1.28 adjusted for race/ethnicity and site; PR = 1.13, CI: 1.01-1.25 further adjusted for BMI), but not thelarche. In longitudinal models, risk of developing allergies increased with younger age at pubarche (adjusted OR = 1.60, CI: 1.10-2.34; ≤10 vs. >10 yr). Risks were highest among black girls with earlier pubarche (n = 248/326); for allergies, their fully adjusted OR was 2.35, CI: 1.06-5.19 for pubarche ≤10 vs. >10 yr.

CONCLUSIONS

Atopic conditions during childhood are associated with younger age at pubarche, independent of obesity, and these relationships may vary by racial/ethnic groups.

What can providers learn from childhood body mass index trajectories: a study of a large, safety-net clinical population

OBJECTIVE

To describe childhood weight gain using body mass index (BMI) z-score trajectories in a low-income urban safety-net population and identify among gender- and race/ethnicity-specific groups any trends for increased risk.

METHODS

A retrospective cohort study was conducted among 2- to 12-year-old patients (2006-2013) visiting a safety-net provider. BMI z-score trajectories were calculated overall, for gender- and race/ethnicity-specific groups, and for peak BMI percentile subgroups to describe weight gain longitudinally.

RESULTS

From 2006 to 2013, a total of 26,234 eligible children were followed for an average of 3.7 years. At baseline (mean age, 4.2 years), 74% of patients were at a normal weight compared to 65% at most recent observation (mean age, 7.8 years). All gender and race/ethnicity subgroups showed increasing average BMI z-scores during childhood. Children consistently under the 50th percentile and those of white race had the most stable BMI z-score trajectories. BMI z-score increased with increasing age in all subgroups. Hispanic boys and black girls had the most significant increase in BMI z-score during this observation period. Children observed in early childhood and whose BMI exceeded the 95th percentile at any time were often already overweight (20%) or obese (36%) by 3 years of age.

CONCLUSIONS

The entire population demonstrated an upward trend in BMI z-score trajectory. This trend was most notable among black girls and Hispanic boys. Many obese children were already overweight by age 3, and persistence of obesity after 3 years of age was high, suggesting that intervention before age 3 may be essential to curbing unhealthy weight trajectories.

The relationship between bioactive components in breast milk and bone mass in infants

Human breast milk (HBM) contains numerous bioactive components, recently shown to be associated with growth and body composition in breastfed offspring. Reciprocity in adipogenic and osteogenic pathways suggests bone mass may also be influenced by these components. The association between bioactive components found in HBM and bone mineral content (BMC), to our knowledge, is unknown. The purpose of this proof-of-principle study was to evaluate the association between specific bioactive components in HBM in exclusively breastfed infants and skeletal health in the first 6 months of life and examine potential gender differences in these associations. Thirty-five mother-infant dyads were followed from 1 to 6 months. The contents of a single breast expression were used for analyses of bioactive components (insulin, glucose, leptin, interleukin-6 and tumor necrosis factor-α (TNFα), whereas BMC was evaluated by dual-energy X-ray absorptiometry. In the total sample, there was a positive association between TNFα and BMC at 1 (P=0.004) and 6 months (P=0.007). When stratified by sex, females exhibited a positive association between BMC and glucose and an inverse relationship between BMC and TNF-α at 1 month with TNF-α strengthening (P=0.006) at 6 months. In males, at 6 months a positive relationship between BMC and HBM glucose and an inverse relationship with HBM leptin were observed with no associations observed at 1 month. Although preliminary, the associations between bioactive components in HBM highlight the importance HBM has on bone accretion. It is critically important to identify factors in HBM that contribute to optimal bone health.

20 years of leptin: leptin and reproduction: past milestones, present undertakings, and future endeavors

The association between leptin and reproduction originated with the leptin-mediated correction of sterility in ob/ob mice and initiation of reproductive function in normal female mice. The uncovering of a central leptin pathway regulating food intake prompted the dissection of neuroendocrine mechanisms involving leptin in the metabolic control of reproduction. The absence of leptin receptors on GnRH neurons incited a search for intermediary neurons situated between leptin-responsive and GnRH neurons. This review addresses the most significant findings that have furthered our understanding of recent progress in this new field. The role of leptin in puberty was impacted by the discovery of neurons that co-express kisspeptin, neurokinin B, and dynorphin and these could act as leptin intermediates. Furthermore, the identification of first-order leptin-responsive neurons in the premammilary ventral nucleus and other brain regions opens new avenues to explore their relationship to GnRH neurons. Central to these advances is the unveiling that agouti-related protein/neuropeptide Y neurons project onto GnRH and kisspeptin neurons, allowing for a crosstalk between food intake and reproduction. Finally, while puberty is a state of leptin sensitivity, mid-gestation represents a state of leptin resistance aimed at building energy stores to sustain pregnancy and lactation. The mechanisms underlying leptin resistance in pregnancy have lagged; however, the establishment of this natural state is significant. Reproduction and energy balance are tightly controlled and backed up by redundant mechanisms that are critical for the survival of our species. It will be the goal of the following decade to shed new light on these complex and essential pathways.

Sex and race (black-white) differences in the relationship of childhood risk factors to adulthood arterial stiffness: the Bogalusa Heart Study

BACKGROUND

Cardiovascular risk factors in childhood are predictive of adulthood arterial stiffness. However, it is unknown whether this relationship varies by race or sex.

METHODS

Six hundred and eighty adults aged 24 to 43 had been followed for an average of 26.3 years, from the Bogalusa Heart Study. Brachial to ankle pulse wave velocity (baPWV) measured by an automatic oscillometric technique was used as the outcome variable for arterial stiffness during adulthood. Body mass index (BMI), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), glucose, and systolic blood pressure (SBP), all measured in childhood, were used as predictors. The average values of childhood measurements at multiple time points were used, standardized to age, race, and sex-specific z-scores.

RESULTS

In the total sample, childhood SBP was the only significant predictor (P < 0.001) for adult baPWV. Significant interactions between sex and BMI (P = 0.001), between sex and LDL-C (P = 0.035), and between race and HDL-C (P = 0.002) on adult baPWV were identified. Childhood predictors of adult baPWV were BMI (30.9 cm/s reduction in baPWV per standard deviation increase, 95% confidence interval [CI]: -55.0, -6.9 cm/s), LDL-C (30.8 cm/s increase, 95% CI: 2.9, 59.5 cm/s), and HDL-C (46.8 cm/s reduction, 95% CI: -76.2, -17.4 cm/s) in white males; SBP (38.2 cm/s increase, 95% CI: 11.0, 65.4 cm/s) in white females; BMI (71.3 cm/s reduction, 95% CI: -119.9, -22.7 cm/s) in black males; and none in black females.

CONCLUSIONS

The associations of childhood cardiovascular risk factors with adult arterial stiffness varied by race and sex.

Measurement and Interpretation of Body Mass Index During Childhood and Adolescence

The landscape of childhood health and disease has changed over the past century, and school nurses are now in a unique position to address the conditions that lead to chronic disease, such as obesity. Measuring body mass index (BMI) during childhood and adolescence is the recommended method for screening and/or monitoring obesity in school communities. Yet changes in the size, proportion, and distribution of fat mass and fat-free mass during growth and development introduce challenges to interpreting BMI measurements. Understanding these challenges and ensuring accurate measurement techniques are the foundation for implementing school-based BMI measurement programs. This article will provide an overview of body composition during childhood and adolescence, introduce strategies to improve the accuracy of BMI measurements, and explore the school nurse's role in BMI surveillance and/or screening activities.

Early and late menarche are associated with oligomenorrhea and predict metabolic syndrome 26 years later

OBJECTIVE

We determined whether simple, clinical information on late and early menarche could help identify adult women with metabolic syndrome (MetS) and oligomenorrhea.

MATERIALS/METHODS

We carried out a 26-year prospective follow-up of 272 suburban schoolgirls from ages 5-22 to 30-46.

RESULTS

Early menarche (≤10 years, 5.2% of girls) and late menarche (≥16 years, 6.7% of girls) were both associated with oligomenorrhea (≥42 days) in adulthood, 29% and 11%, vs. 5% for normal menarche (11-15 years), p=.004. Early menarche was characterized by high childhood BMI (LS mean±SE: 21.2 ±1.0 kg/m2) and by high childhood and adult MetS (15%, 36%). Girls with late menarche had the lowest childhood BMI (18.1±1.0), no childhood MetS, and the highest adult MetS (47%). Increasing age at menarche was associated with uniformly decreasing childhood BMI and MetS, but with a U-shaped pattern of BMI (p = .05), MetS (p=.008), and oligomenorrhea (p=.02) in adulthood. Change to MetS from median ages 13 to 38 was associated with early-late menarche (OR=3.11, 95% CI 1.37-7.07, p=.007). MetS in adulthood was associated with childhood MetS (OR=8.03, 95% CI 2.57-25.08, p=.0003) and with early-late menarche (OR =3.43, 95% CI 1.44-8.15, p=.005).

CONCLUSIONS

Menarche age had a curvilinear ('U' shaped) relationship with MetS and oligomenorrhea in adulthood. Late menarche and early menarche are risk factors for adult oligomenorrhea, MetS, and cardiometabolic abnormalities. Girls with early (≤ age 10) and with late menarche (≥ 16) represent a group at high risk for adult cardiometabolic abnormalities and oligomenorrhea that is easily identifiable by physicians.

Relative fat distribution in relation to menarcheal status among Bengalee Hindu girls of West Bengal, India

Background:

Menarche seems be related to the relative distribution rather than the total amount of body fat. Previous studies showed that the ratio between lower-body vs. upper-body fat was associated with the timing of menarche.

Aim:

To compare the relative distribution of subcutaneous fat among Bengali Hindu pre- and post-menarcheal girls.

Materials and Methods:

The participants were 234 Bengali Hindu girls aged 11-14 years: 111 pre-menarcheal and 123 post-menarcheal girls, randomly selected from a secondary school from a suburb of Kolkata, West Bengal, India. Triceps, abdominal, sub-scapular, and calf skinfolds were measured. For each skinfold site, ratio was calculated as follows: Log (one skinfold/sum of skinfolds). Principal components (PC) analysis was performed to derive components which express the maximum contrast among the log of ratios. T-test was employed to assess differences between individual scores of components between pre- and post-menarcheal girls.

Results:

The three identified PC suggested extremities-trunk, lower trunk-upper trunk, and an upper extremity-lower extremity contrasts, respectively. Scores for second and third components showed significant differences between pre- and post-menarcheal groups of girls.

Conclusion:

The attainment of menarche by Bengali girls aged 11-14 years was associated with characteristically more relative subcutaneous fat distribution in the upper trunk and in the lower limbs, in contrast to lower trunk and upper limbs, respectively.

Childhood Obesity Prevention and Treatment Research (COPTR): interventions addressing multiple influences in childhood and adolescent obesity

This paper is the first of five papers in this issue that describes a new research consortium funded by the National Institutes of Health. It describes the design characteristics of the Childhood Obesity Prevention and Treatment Research (COPTR) trials and common measurements across the trials. The COPTR Consortium is conducting interventions to prevent obesity in pre-schoolers and treat overweight or obese 7-13 year olds. Four randomized controlled trials will enroll a total of 1700 children and adolescents (~50% female, 70% minorities), and will test innovative multi-level and multi-component interventions in multiple settings involving primary care physicians, parks and recreational centers, family advocates, and schools. For all the studies, the primary outcome measure is body mass index; secondary outcomes, moderators and mediators of intervention include diet, physical activity, home and neighborhood influences, and psychosocial factors. COPTR is being conducted collaboratively among four participating field centers, a coordinating center, and NIH project offices. Outcomes from COPTR have the potential to enhance our knowledge of interventions to prevent and treat childhood obesity.

The secret struggle of the active girl: a qualitative synthesis of interpersonal factors that influence physical activity in adolescent girls

The author conducted a systematic review of 19 international, multidisciplinary, qualitative studies of interpersonal factors that influence physical activity in adolescent girls. Themes were deductively generated based on reported findings, and were organized according to frequency of occurrence. Themes were further organized according to a theoretical model to illustrate how interpersonal, perceptual, and situational influences affect physical activity in adolescent girls. The three most frequently discovered themes follow: (a) ability comparison and competition; (b) family, peer, and teacher influence; and (c) appearance concerns. It is important to consider the influence of gender role conflict on physical activity.

Genome-wide association study of age at menarche in African-American women

African-American (AA) women have earlier menarche on average than women of European ancestry (EA), and earlier menarche is a risk factor for obesity and type 2 diabetes among other chronic diseases. Identification of common genetic variants associated with age at menarche has a potential value in pointing to the genetic pathways underlying chronic disease risk, yet comprehensive genome-wide studies of age at menarche are lacking for AA women. In this study, we tested the genome-wide association of self-reported age at menarche with common single-nucleotide polymorphisms (SNPs) in a total of 18 089 AA women in 15 studies using an additive genetic linear regression model, adjusting for year of birth and population stratification, followed by inverse-variance weighted meta-analysis (Stage 1). Top meta-analysis results were then tested in an independent sample of 2850 women (Stage 2). First, while no SNP passed the pre-specified P < 5 × 10(-8) threshold for significance in Stage 1, suggestive associations were found for variants near FLRT2 and PIK3R1, and conditional analysis identified two independent SNPs (rs339978 and rs980000) in or near RORA, strengthening the support for this suggestive locus identified in EA women. Secondly, an investigation of SNPs in 42 previously identified menarche loci in EA women demonstrated that 25 (60%) of them contained variants significantly associated with menarche in AA women. The findings provide the first evidence of cross-ethnic generalization of menarche loci identified to date, and suggest a number of novel biological links to menarche timing in AA women.

Insulin resistance and truncal obesity as important determinants of the greater incidence of diabetes in Indian Asians and African Caribbeans compared with Europeans: the Southall And Brent REvisited (SABRE) cohort

OBJECTIVE

To determine the extent of, and reasons for, ethnic differences in type 2 diabetes incidence in the U.K.

RESEARCH DESIGN AND METHODS

Population-based triethnic cohort. Participants were without diabetes, aged 40-69 at baseline (1989-1991), and followed-up for 20 years. Baseline measurements included fasting and postglucose bloods, anthropometry, and lifestyle questionnaire. Incident diabetes was identified from medical records and participant recall. Ethnic differences in diabetes incidence were examined using competing risks regression.

RESULTS

Incident diabetes was identified in 196 of 1,354 (14%) Europeans, 282 of 839 (34%) Indian Asians, and 100 of 335 (30%) African Caribbeans. All Indian Asians and African Caribbeans were first-generation migrants. Compared with Europeans, age-adjusted subhazard ratios (SHRs [95% CI]) for men and women, respectively, were 2.88 (95%, 2.36-3.53; P < 0.001) and 1.91 (1.18-3.10; P = 0.008) in Indian Asians, and 2.23 (1.64-3.03; P < 0.001) and 2.51 (1.63-3.87; P < 0.001) in African Caribbeans. Differences in baseline insulin resistance and truncal obesity largely attenuated the ethnic minority excess in women (adjusted SHRs: Indian Asians 0.77 [0.49-1.42]; P = 0.3; African Caribbeans 1.48 [0.89-2.45]; P = 0.13), but not in men (adjusted SHRs: Indian Asians 1.98 [1.52-2.58]; P < 0.001 and African Caribbeans, 2.05 [1.46-2.89; P < 0.001]).

CONCLUSIONS

Insulin resistance and truncal obesity account for the twofold excess incidence of diabetes in Indian Asian and African Caribbean women, but not men. Explanations for the excess diabetes risk in ethnic minority men remains unclear. Further study requires more precise measures of conventional risk factors and identification of novel risk factors.

Childhood obesity and risk of pediatric multiple sclerosis and clinically isolated syndrome

OBJECTIVE

To determine whether childhood obesity is a risk factor for developing pediatric multiple sclerosis (MS) or clinically isolated syndrome (CIS).

METHODS

Cases were identified through the Kaiser Permanente Southern California (KPSC) pediatric acquired demyelinating diseases cohort between 2004 and 2010. For cases, body mass index (BMI) was obtained prior to symptom onset, for the underlying cohort BMI was obtained through the KPSC Children's health study (n = 913,097). Weight classes of normal weight, overweight, moderate obesity, and extreme obesity were assigned based on BMI specific for age and sex.

RESULTS

We identified 75 newly diagnosed pediatric cases of MS or CIS, the majority of which were in girls (n = 41, 55%), age 11-18 (n = 54, 72%). Obesity was associated with a significantly increased risk of MS/CIS in girls (p = 0.005 for trend) but not in boys (p = 0.93). The adjusted odds ratio and 95% confidence intervals for CIS/MS among girls was 1.58 (0.71-3.50) for overweight compared to normal weight (reference category), 1.78 (0.70-4.49) for moderately obese, and 3.76 (1.54-9.16) for extremely obese. Moderately and extremely obese cases were more likely to present with transverse myelitis compared with normal/overweight children (p = 0.003).

CONCLUSION

Our findings suggest the childhood obesity epidemic is likely to lead to increased morbidity from MS/CIS, particularly in adolescent girls.

Longitudinal analysis of growth and body composition of Japanese 21-OHD patients in childhood

Substitution therapy of glucocorticoid is a major part of the treatment for 21-OHD (21-hydroxylase deficiency). However, the therapy causes two major adverse effects, impairment of linear growth and obesity, so that collecting precise growth data is essential for optimizing the therapy. We longitudinally evaluated the linear growth and the body composition of Japanese 21-OHD patients during childhood. For the present study, we chose 16 patients (eight of each sex) who were diagnosed during the newborn period, and continuously observed them in our institute until they were at least 15 years old. All patients were treated according to the guidelines from The Japanese Society for Pediatric Endocrinology. The final height standard deviation score (Ht-SDS) of all the patients was -1.18 ± 0.85 SD, and no significant differences were observed between males and females or between the simple virilizing form and the salt wasting form. As previously reported, in spite of nearly normal height at the onset of puberty, the pubertal height gains were severely impaired, resulting in reduced final heights. Body composition of the patients was evaluated with BMI-SDS. Our longitudinal data showed that BMI was increased up to +1.23 SD in males and up to +1.75 SD in females, and that adiposity rebound was precipitated. Our study should alert physicians to the risk of metabolic syndrome and provide a framework for further studies of metabolic syndrome in 21-OHD patients.

Determinants of ApoB, ApoA1, and the ApoB/ApoA1 ratio in healthy schoolgirls, prospectively studied from mean ages 10 to 19 years: the Cincinnati National Growth and Health Study

The objectives were to prospectively assess determinants of apolipoproteins B (ApoB), A1 (ApoA1), and the ApoB/ApoA1 ratio in 797 healthy black and white schoolgirls from mean ages 10 to 19. There was prospective 9-year follow-up, with measures of ApoB at mean ages 10, 12, 14, 16 and 19, ApoA1 at mean ages 12, 14, 16, and 19, and assessment of annual reports of delayed menstrual cyclicity (≥42 days) from ages 14 to 19. Studies of 402 black and 395 white healthy schoolgirls were done in public and private schools, in urban and suburban Cincinnati. Black girls had lower ApoB, higher ApoA1, and lower ApoB/ApoA1. SHBG at age 14 in white and black girls was inversely correlated with the ApoB/ApoA1. At age 19, ≥3 annual reports of menstrual delay ≥42 days and metabolic syndrome were associated with higher ApoB and a higher ApoB/ApoA1 ratio. From ages 14 to 19, BMI and TG were independently positively associated with ApoB. Menstrual cyclicity ≥42 days, metabolic syndrome, BMI, and TG were independently positively associated with ApoB/ApoA1 ratios, while black race was negatively associated. The atherogenic ApoB/ApoA1 ratio from ages 14 to 19 is lower in black girls, and positively associated with hyperandrogenism, menstrual cyclicity ≥42 days, BMI, TG, and the metabolic syndrome, facilitating an adolescent approach to primary prevention of cardiovascular disease.

Estimating Body Fat from Anthropometry and Isotopic Dilution: A Four-Country Comparison

OBJECTIVE

The goal was to assess the ability of BMI to predict body fat (BF) among youths in four countries and identify the degree to which additional anthropometric measures improve this prediction. BMI is widely recommended as an indicator of overweight. However, whether BMI adequately estimates BF and has the same meaning in different ethnic groups and youths has been questioned.

RESEARCH METHODS AND PROCEDURES

Data come from 456 Filipino, Chinese, Russian, and black South African youths, 6 to 16 years old. Percentage BF and fat mass index (FMI) were estimated by the deuterium dilution method. Skinfold thicknesses (triceps, subscapular, and suprailiac) and weight and height measures were collected. Percentage BF was regressed first on BMI and age and then with the addition of the skinfold measures. Linear models were run separately by country and sex. The models were repeated with FMI as the outcome.

RESULTS

The R2 values from the percentage BF models ranged from 0.13 to 0.69 in the first models to 0.38 to 0.81 in the full models. The values were lowest among Russian males > or = 13 years and Russian females > or = 13 years of age in the reduced and full models, respectively, and were highest among Chinese females. Using FMI as the outcome did not meaningfully change the results.

DISCUSSION

The ability of BMI to adequately predict BF and the additional predictivity of anthropometric measures varied widely across the samples, making its uniform use as a proxy for BF in youths from different countries questionable.

A shift from underweight to overweight and obesity in Asian children and adolescents with congenital heart disease

BACKGROUND

In Western countries, obesity is a common problem in children with congenital heart disease (CHD). However, this problem may have racial difference, and little is known about the shift of this trend as patients grow up. The present study sought to investigate the prevalence and trends of being underweight, overweight and obesity in an Asian CHD cohort using a 5-year citywide school survey database.

METHODS

Patient group consisted of 705 first grade elementary school students (children) and 219 first grade senior high school students (adolescents), while 18753 healthy children and 15014 healthy adolescents served as controls. Body mass index (BMI) percentile was calculated to define underweight (BMI < 15(th) percentile) and overweight (BMI 85(th) -95(th) percentile)/obesity (BMI ≥ 95(th) percentile).

RESULTS

In CHD children, the prevalence of underweight and overweight/obesity was 21.0% (control 16%, P < 0.001) and 14.5% (control 19.8%, P < 0.001), respectively. Children with moderate to severe CHD, especially cyanotic CHD, were more underweight and less overweight/obese than children with non-cyanotic CHD. The prevalence of underweight (23.3%) and overweight/obesity (26.5%) in CHD adolescents became close to that in controls. From childhood to adolescence, different shifts in BMI distribution were noted; controls became more underweight and overweight/obese for males and more underweight and less overweight/obese for females, while CHD patients became more overweight/obese for both genders, including cyanotic CHD.

CONCLUSIONS

In this Asian CHD cohort, we demonstrates a shift of BMI distribution from more underweight and less overweight/obese compared with healthy children, to a pattern similar to that in healthy adolescents.

Reduced carbohydrate diet to improve metabolic outcomes and decrease adiposity in obese peripubertal African American girls

OBJECTIVE

Obesity prevalence among African American (AA) girls is higher than that in other groups. Because typical energy-restriction obesity treatment strategies have had limited success, alterations in macronutrient composition may effectively improve metabolic outcomes in this population and affect future body composition trajectories. The objective was to evaluate the efficacy of a moderately restricted carbohydrate (CHO) versus a standard CHO diet on weight/fat loss and metabolic parameters in overweight/obese AA girls ages 9 to 14 years.

METHODS

A total of 26 AA girls (ranging from 92nd body mass index percentile and above) were assigned to either a reduced- (SPEC: 42% energy from CHO, n = 12) or a standard- (STAN: 55% of energy from CHO, n = 14) CHO diet (protein held constant) for 16 weeks. All of the meals were provided and clinically tailored to meet the estimated energy requirements (resting energy expenditure × 1.2 in eucaloric phase and resting energy expenditure × 1.2 - 1000 kcal in energy deficit phase). The first 5 weeks encompassed a eucaloric phase evaluating metabolic changes in the absence of weight change. The subsequent 11 weeks were hypocaloric (1000 kcal/day deficit) to promote weight/fat loss. Meal tests were performed during the eucaloric phase for metabolic analyses. Dual-energy x-ray absorptiometry was used to evaluate body composition.

RESULTS

Both groups experienced reductions in weight/adiposity, but the difference did not reach significance. The solid meal test indicated improved glucose/insulin homeostasis on the SPEC diet up to 3 hours postingestion. In addition, significantly lower triglycerides (P < 0.001) were observed on the SPEC diet.

CONCLUSIONS

Dietary CHO reduction favorably influences metabolic parameters but did not result in greater weight/fat loss relative to a standard diet in obese AA girls. Future research is needed to determine long-term effectiveness of a reduced CHO diet on glucose and insulin homeostasis and how it may apply to weight maintenance/fat loss during development alone and/or in combination with additional weight loss/metabolic improvement strategies.

Heritabilities of Lipids in Young European American and African American Twins

Twin studies of lipids have almost exclusively involved Caucasians. People of African descent are known to show a healthier lipid profile, but relatively little is known about ethnic differences in genetic and environmental influences on lipids. One hundred and six African American (AA) and 106 European American (EA) twins (30 singletons and 91 complete pairs: 49 monozygotic, 21 dizygotic and 21 opposite-sex) from the south-eastern United States were studied (mean age 17.9 ± 3.2 years; 79% fasting). Lipids were assayed with the Cholestech LDX system. Analyses were adjusted for fasting status. Generalized estimating equations were used to test for the effects of sex and ethnicity on means, controlling for the dependence within twin pairs. Structural equation modeling was used to estimate genetic and environmental effects on each lipid variable. Females showed higher high-density lipoprotein (HDL) values than males (p< .001) and AAs showed higher HDL values than EAs (p< .001). EA males had higher triglyceride values than other groups (p= .02). All parameter estimates could be set equal across sex. Parameter estimates for total cholesterol, triglycerides and HDL could be set equal across ethnicity. The best fitting model for low- density lipoprotein (LDL) showed higher heritability in AAs (.92) than EAs (.69). Heritabilities ranged from 69% to 92%, with remaining variation explained by nonshared environmental effects. Adjustment for body mass index had virtually no effect on the heritability estimates. In this first twin study on lipids to include AAs, no ethnic differences in heritability were found except for LDL, where AAs exhibited higher estimates.

Divergent body mass index trajectories between Aboriginal and non-Aboriginal Canadians 1994-2009--an exploration of age, period, and cohort effects

OBJECTIVES

Aboriginal Canadians have a high burden of obesity and obesity-related chronic conditions. Body mass index (BMI) trajectories from 1994 to 2009 were estimated for Aboriginal and non-Aboriginal Canadians using self-reported height and weight data from the National Population Health Survey to explore age, period, and cohort effects of BMI change.

METHODS

Linear growth curve models were estimated for 311 Aboriginal and 10,967 non-Aboriginal respondents divided into five birth cohorts born in the 1940s, 50s, 60s, 70s, and 80s.

RESULTS

Overall, Aboriginal Canadians experienced higher rates of BMI increase over the 14-year period. Rate of BMI increase was specifically higher for Aboriginal adults born in the 1960s and 1970s when compared with non-Aboriginal adults. At ages 25, 35, and 45, recent-born cohorts had consistently higher BMIs compared with earlier-born cohorts with magnitudes of differences typically larger in the Aboriginal population. Recent-born cohorts also exhibited steeper BMI trajectories.

CONCLUSIONS

Cohort effects may be responsible for the divergent BMI trajectories between Aboriginal and non-Aboriginal Canadians born in the 1960s and 1970s. Aboriginal Canadians, particularly of more recent-born cohorts, experienced faster increases in BMI from 1994 to 2009 than non-Aboriginal Canadians, suggesting that prevalence of obesity will continue to rise in this population without intervention.

Physical activity and the achievement gap among urban minority youth

OBJECTIVES

To outline the prevalence and disparities of physical activity among school-aged urban minority youth, causal pathways through which low levels of physical activity and fitness adversely affects academic achievement, and proven or promising approaches for schools to increase physical activity and physical fitness among youth.

METHODS

Literature review.

RESULTS

A large proportion of youth is insufficiently physically active. Estimates of population-wide levels of physical activity indicate that Black and Hispanic youth are less physically active than White youth, with disparities particularly evident for females. The population segments of youth with lowest levels of physical activity and fitness also have least access to school-based physical activity opportunities and resources. Physical activity affects metabolism and all major body systems, exerting powerful positive influences on the brain and spinal cord and, consequently, on emotional stability, physical health, and motivation and ability to learn. The cornerstone of school-based physical activity programs should be a high-quality physical education program based on national standards. Such programs are strongly recommended by the Task Force on Community Preventive Services as a way to increase physical activity and physical fitness among youth.

CONCLUSIONS

Physical inactivity is highly and disproportionately prevalent among school-aged urban minority youth, has a negative impact on academic achievement through its effects on cognition, and effective practices are available for schools to address this problem. Increasing students' physical activity and physical fitness can best be achieved through a comprehensive approach that includes physical education, wise use of recess and after-school times, co-curricular physical activity opportunities, and bicycling or walking to and from school.

Sex hormone-binding globulin, oligomenorrhea, polycystic ovary syndrome, and childhood insulin at age 14 years predict metabolic syndrome and class III obesity at age 24 years

OBJECTIVE

We hypothesized that oligomenorrhea (menstrual cyclicity ≥42 days), hyperandrogenism, low levels of sex hormone-binding globulin (SHBG), childhood insulin, and metabolic syndrome (MetS) at age 14 years would predict MetS and class III obesity (body mass index ≥40 kg/m(2)) at age 24 years.

STUDY DESIGN

In this prospective study of schoolgirls, at age 14 years, the girls were categorized as regularly cycling (n = 375), oligomenorrheic (n = 18), or oligomenorrhea plus biochemical hyperandrogenism (polycystic ovary syndrome [PCOS]; n = 12), together designated PCOS.

RESULTS

Significant explanatory variables for MetS at age 24 years included childhood insulin, MetS, and PCOS category (all positive) and SHBG (negative) at age 14 years. Using categorical data, top decile of childhood insulin, MetS at age 14, bottom decile of SHBG, and PCOS category were significant positive predictors for MetS at age 24. SHBG (negative), black race (positive), and oligomenorrhea (positive) were significant explanatory variables for class III obesity at age 24. Using categorical data, black race, MetS at age 14, bottom decile of SHBG, PCOS category, and top decile of childhood insulin were positive explanatory variables for class III obesity at age 24 years.

CONCLUSIONS

Oligomenorrhea, PCOS (a subcohort of oligomenorrhea), hyperandrogenism, low SHBG, MetS, and childhood insulin at age 14 years may represent a critical, reversible pathway for the development of MetS and class III obesity in young adulthood.

Trajectories of overweight among US school children: a focus on social and economic characteristics

Much of the research examining the patterns, timing, and socioeconomic characteristics of child overweight has been limited by the lack of longitudinal nationally representative data with sufficiently large or diverse samples. We used the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K), a nationally representative sample of US kindergartners, to identify three distinct patterns of weight gain from kindergarten through eighth grade. The largest group (boys: 59%, girls: 55%) was characterized as having consistently normal weight whereby BMI percentile remained below the 85th percentile. The remaining children (boys: 41%, girls: 45%) fell either into a class characterized as always overweight/at risk of overweight (boys: 27%, girls: 25%) or gradually becoming overweight/at risk for overweight (boys: 15%, girls 20%). We found some evidence that the relationship between socioeconomic status and children's health may operate differently across gender. Among girls, low parental income and education were both significant risk factors for the gradual onset of overweight after beginning Kindergarten. Parental income or changes in parental income were not related to boys' risk of developing overweight after entering Kindergarten; only parents' education. We found that while children of immigrants display higher levels of overweight/at risk for overweight at each grade level, the children of immigrant parents who have had less exposure to the US were more likely to experience early and sustained overweight throughout elementary and middle school, particularly among boys. High rates of overweight as early as kindergarten, combined with race/ethnic differences suggest that interventions should focus on pre-school children's environments.

Ethnic differences in body fat distribution among Asian pre-pubertal children: a cross-sectional multicenter study

Background

Ethnic differences in body fat distribution contribute to ethnic differences in cardiovascular morbidities and diabetes. However few data are available on differences in fat distribution in Asian children from various backgrounds. Therefore, the current study aimed to explore ethnic differences in body fat distribution among Asian children from four countries.

Methods

A total of 758 children aged 8-10 y from China, Lebanon, Malaysia and Thailand were recruited using a non-random purposive sampling approach to enrol children encompassing a wide BMI range. Height, weight, waist circumference (WC), fat mass (FM, derived from total body water [TBW] estimation using the deuterium dilution technique) and skinfold thickness (SFT) at biceps, triceps, subscapular, supraspinale and medial calf were collected.

Results

After controlling for height and weight, Chinese and Thai children had a significantly higher WC than their Lebanese and Malay counterparts. Chinese and Thais tended to have higher trunk fat deposits than Lebanese and Malays reflected in trunk SFT, trunk/upper extremity ratio or supraspinale/upper extremity ratio after adjustment for age and total body fat. The subscapular/supraspinale skinfold ratio was lower in Chinese and Thais compared with Lebanese and Malays after correcting for trunk SFT.

Conclusions

Asian pre-pubertal children from different origins vary in body fat distribution. These results indicate the importance of population-specific WC cut-off points or other fat distribution indices to identify the population at risk of obesity-related health problems.

Ramifications of adolescent menstrual cycles ≥42 days in young adults

OBJECTIVE

To determine to what degree annual reports from ages 14 to 19 years of menstrual cycles ≥42 days would be associated with increased body mass index (BMI), waist circumference, glucose, insulin, and homeostasis model assessment insulin resistance (HOMA-IR) at ages 14-25 years.

DESIGN

Prospective 11-year follow-up from ages 14 to 25 years.

SETTING

Urban-suburban schools, post-high school.

PATIENT(S)

A total of 370 schoolgirls.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

BMI, waist, insulin, glucose, HOMA-IR.

RESULT(S)

From ages 14 to 19 years, 269 girls had 0/6 annual reports of menstrual cycles ≥42 days, 74 had 1, 19 had 2, and 8 had ≥3. Among these four categories, girls with ≥3 annual reports had highest free T and DHEAS at age 14, highest BMI and waist at ages 14, 19, and 25, highest insulin at age 25, and highest glucose and HOMA-IR at age 24 years. The number of annual reports of menstrual cycles ≥42 days was positively related to change in BMI and waist and inversely with change in high-density lipoprotein cholesterol from ages 14 to 25 years.

CONCLUSION(S)

Three or more annual reports of menstrual cycles ≥42 days during ages 14-19 are associated with high BMI, waist circumference, insulin, glucose, and HOMA-IR at ages 14-25 years.

Female overweight and obesity in adolescence: developmental trends and ethnic differences in prevalence, incidence, and remission

Despite substantial increases in the prevalence of adolescent overweight and obesity documented in recent decades, few studies have prospectively tracked their development during the entire adolescent period. The aims of this study were to characterize developmental trends in prevalence, incidence, and remission of overweight and obesity using annual data collected from ages 12 to 19 for 496 adolescent females. Ethnic differences between African American (n = 37), Latina (n = 96), and European American (n = 348) adolescents were also compared. The prevalence of overweight decreased slightly across adolescence and remission rates exceeded incidence (onset). Obesity was more chronic, with increasing incidence accompanied by decreasing remission rates. Middle through late adolescence was the period of greatest risk for the transition from overweight to obesity. African American and Latina females had higher overweight and obesity prevalence than European American females throughout adolescence. Differences in prevalence were driven by higher onset rates for African American and Latina females, whereas remission rates were comparable across ethnic groups. Results suggest that adolescence is not a high-risk period for onset of obesity for European American adolescent females, but is for African American and Latina adolescent females.

Ethnicity, obesity and the metabolic syndrome: implications on assessing risk and targeting intervention

Pediatric obesity threatens the future health of a growing number of children worldwide. An added challenge in identifying the patients at greatest need for intervention due to their elevated risk for future disease is that pediatric obesity and the associated metabolic syndrome manifest differently among different ethnic groups. African-Americans and Hispanics are more likely to exhibit obesity and insulin resistance and are at a higher risk for developing Type 2 diabetes. Nevertheless, using current criteria, African-American adolescents are much less likely to be diagnosed with metabolic syndrome, largely owing to lower rates of dyslipidemia. Further development is needed in ethnicity-inclusive means of risk identification among adolescents to accurately target treatment toward children at highest risk for future disease and to motivate adolescent patients and their families towards lifestyle improvement. Effective targeting and intensive treatment efforts may help in avoiding future sequelae of obesity among all ethnicities.