Overweight, fat patterning, and cardiovascular disease risk factors in black and white boys

Cross-cultural Adaptation and Validation of the Japanese Version of the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS)

Background:

The Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) is a specifically designed scoring system for children and has been translated into several languages. However, to date, no validated Japanese version of this scoring system is available.

Purpose:

To translate the HSS Pedi-FABS into Japanese and assess its reliability and validity.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

The HSS Pedi-FABS was translated into Japanese and back-translated into English to confirm the appropriateness of the translation. A total of 764 children aged 9 to 15 years participated in the validation study. The participants answered the Japanese version of the HSS Pedi-FABS along with 2 other questionnaires in Japanese (the Physical Activity Questionnaire for Older Children [PAQ-C] and the physical activity questionnaire of the World Health Organization’s Health Behavior in School-aged Children [HBSC PAQ]). At 1 month after the first assessment, the children answered the Japanese version of the HSS Pedi-FABS again. We evaluated reliability using the Cronbach alpha and the intraclass correlation coefficient. Validity was evaluated by quantifying floor and ceiling effects, correlations between the HSS Pedi-FABS and the PAQ-C, the HSS Pedi-FABS discrepancy between active and inactive groups divided by the HBSC PAQ, and correlation between the HSS Pedi-FABS and body mass index.

Results:

HSS Pedi-FABS scores were slightly but significantly higher in male participants (mean = 16.7) than in female participants (mean = 13.2). The Cronbach alpha coefficient was .90, and the intraclass correlation coefficient value was 0.90, indicating excellent internal consistency and test-retest reliability, respectively. No floor (2.6%) or ceiling effect (1.0%) was observed. The HSS Pedi-FABS was significantly correlated with the PAQ-C (r = 0.70). The active group demonstrated a significantly higher score on the HSS Pedi-FABS (mean = 18.9) than did the inactive group (mean = 11.2). In terms of discriminative validity, the HSS Pedi-FABS was not correlated with body mass index (r = –0.15).

Conclusion:

The Japanese version of the HSS Pedi-FABS demonstrated appropriate reliability and validity, indicating that it is a useful tool to assess physical activity levels in Japanese children.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

Chinese men living in urban areas of Shijiazhuang, Hebei at higher risk of overweight or obesity

Objective

The prevalence of overweight/obesity in China has increased dramatically in recent years; being overweight/obese can increase the risk of type 2 diabetes and cardiovascular disease. The purpose of this study was to determine the population in China at high risk of being overweight or obese, to explore the relationships between various relevant factors and overweight/obesity, and to identify preventive efforts for high-risk populations.

Methods

We administered a questionnaire survey among a group of 536 social workers in Shijiazhuang City in 2017. We used the Pearson chi-square test, Spearman’s rho test, multivariate linear regression, univariate and multivariate logistic regression, and receiver operating characteristic curve analysis to investigate factors that influence overweight/obesity.

Results

The prevalence of overweight/obesity was 13.7% among the study participants. Urban residence, eating speed, number of daily meals, overeating, and a high-fat diet were associated with overweight/obesity. In multivariate linear regression analysis, overweight/obesity was correlated with sex, urban residence, eating speed, number of daily meals, and a high-fat diet.

Conclusion

Among all influencing factors, dietary factors, place of residence, and sex were most closely related to being overweight/obese. Furthermore, living in an urban area and male sex were independent risk factors for being overweight/obese.

Prevalence of obesity in children enrolled in private and public primary schools

BACKGROUND

Obesity is a growing scourge in Africa. More and more children are exposed to it. This study was designed to assess obesity in children enrolled in private and public primary schools in three communes in the health district of Abidjan, in the south of Côte d'Ivoire.

METHODS

This study involved 1251 children enrolled in six schools due to two schools per municipality (Cocody, Yopougon and Treichville) including 587 boys and 664 girls aged 5-15 years. Children were recruited from private and public primary schools. Anthropometric parameters (Weight, Height, waist circumference, Body mass index) and blood pressure were measured. Data on eating habits were collected using a questionnaire.

RESULTS

Overall, 1251 children were enrolled, or 592 and 659 children in private and public primary schools, respectively. The majority of the children (54.2% [678/1251]) were of normal weight. However, 35.5%, 7.8% and 2.4% of the children were, respectively, underweight, overweight and obese. Overweight including obesity was 10.2%. Overweight and abdominal obesity were common among girls compared to boys (χ² = 0.113, P = 0.001). The low obesity rate (2.4%) observed in our study is probably due to the fact that children are very active. The prevalence of hypertension in overweight people, including obese, was 20.3%. Systolic and diastolic blood pressure was influenced by both BMI and gender with higher systolic (χ² = 0.142, P = 0.001) and diastolic (χ² = 0.135, P = 0.001) blood pressure observed in girls.

CONCLUSION

Our study points out that in addition to a sedentary lifestyle; obesity is also linked to the socio-economic status and daily diet of children. We recommend introducing and operationalizing sports activity in the education system in order to reduce the frequency of obesity and its corollary of metabolic diseases among children.

Childhood obesity and the associated rise in cardiometabolic complications

Childhood obesity is one of the most serious global public-health challenges of the twenty-first century. Over the past four decades, the number of children and adolescents with obesity has risen more than tenfold. Worldwide, an increasing number of youth are facing greater exposure to obesity throughout their lives, and this increase will contribute to the early development of type 2 diabetes, fatty liver and cardiovascular complications. Herein, we provide a brief overview of trends in the global shifts in, and environmental and genetic determinants of, childhood obesity. We then discuss recent progress in the elucidation of the central role of insulin resistance, the key element linking obesity and cardiovascular-risk-factor clustering, and the potential mechanisms through which ectopic lipid accumulation leads to insulin resistance and its associated cardiometabolic complications in obese adolescents. In the absence of effective prevention and intervention programs, childhood obesity will have severe public-health consequences for decades to come.

Systematic estimation of BMI: A novel insight into predicting overweight/obesity in undergraduates

The prevalence of overweight-obesity has increased sharply among undergraduates worldwide. In 2016, approximately 52% of adults were overweight-obese. This cross-sectional study aimed to investigate the prevalence of overweight-obesity and explore in depth the connection between eating habits and overweight-obesity among Chinese undergraduates.The study population included 536 undergraduates recruited in Shijiazhuang, China, in 2017. They were administered questionnaires for assessing demographic and daily lifestyle characteristics, including sex, region, eating speed, number of meals per day, and sweetmeat habit. Anthropometric status was assessed by calculating the body mass index (BMI). The determinants of overweight-obesity were investigated by the Pearson χ test, Spearman rho test, multivariable linear regression, univariate/multivariate logistic regression, and receiver operating characteristic curve analysis.The prevalence of undergraduate overweight-obesity was 13.6%. Sex [male vs female, odds ratio (OR): 1.903; 95% confidence interval (95% CI): 1.147-3.156], region (urban vs rural, OR: 1.953; 95% CI: 1.178-3.240), number of meals per day (3 vs 2, OR: 0.290; 95% CI: 0.137-0.612), and sweetmeat habit (every day vs never, OR: 4.167; 95% CI: 1.090-15.933) were significantly associated with overweight-obesity. Eating very fast was positively associated with overweight-obesity and showed the highest OR (vs very slow/slow, OR: 5.486; 95% CI: 1.622-18.553). However, the results of multivariate logistic regression analysis indicated that only higher eating speed is a significant independent risk factor for overweight/obesity (OR: 17.392; 95% CI, 1.614-187.363; P = .019).Scoremeng = 1.402 × scoresex + 1.269 × scoreregion + 19.004 × scoreeatin speed + 2.546 × scorenumber of meals per day + 1.626 × scoresweetmeat habit and BMI = 0.253 × Scoremeng + 18.592. These 2 formulas can help estimate the weight status of undergraduates and predict whether they will be overweight or obese.

Reliability and Validity of the Japanese Version of the Physical Activity Questionnaire for Older Children

Objectives

This study aimed to examine the reliability and validity of the Japanese version of the Physical Activity Questionnaire for Older Children (PAQ-C) in Japanese children aged 9 to 12 years.

Methods

A total of 210 children aged between 9 and 12 years participated. Internal consistency and test-retest reliability were evaluated using Cronbach alpha coefficient and intraclass correlation coefficient (ICC), respectively. Validity was evaluated using athletic competence (AC), self-efficacy (SE), body mass index (BMI), body fat percentage (%BF), cardiovascular fitness (CVF), and World Health Organization Health Behavior in School-aged Children (WHO HBSC) physical activity questionnaire.

Results

Internal consistency was acceptable (alpha = 0.80) and test-retest reliability showed excellent agreement (ICC = 0.83). The PAQ-C score was significantly correlated with AC (r = 0.41), SE (r = 0.65), %BF (r = 0.19), and CVF (r = -0.32). The PAQ-C score of the active group classified by the WHO HBSC physical activity questionnaire (mean score ± standard deviation [SD] = 3.03 ± 0.57) was significantly higher than that of the inactive group (mean score ± SD = 2.27 ± 0.63, P < .01).

Conclusions

The PAQ-C had acceptable reliability and validity. The PAQ-C is a useful instrument to evaluate physical activity for Japanese children aged 9 to 12 years.

Obesity among Black Adolescent Girls: Genetic, Psychosocial, and Cultural Influences

This article focuses on the causes, consequences, and prevention of obesity among a subgroup of the American population, Black adolescent girls. Using an ecological perspective on obesity among Black adolescent girls, including feminist-womanist perspectives and historical and medical sociological perspectives, the authors discuss genetic, psychosocial, and cultural factors that may influence the propensity of Black adolescent girls’ susceptibility to obesity and to diabetes, one of the major complications of obesity. Prevention strategies, including individual and structural interventions, are illuminated.

Development of an aerobic capacity prediction model from one-mile run/walk performance in adolescents aged 13-16 years

A popular algorithm to predict VO2Peak from the one-mile run/walk test (1MRW) includes body mass index (BMI), which manifests practical issues in school settings. The purpose of this study was to develop an aerobic capacity model from 1MRW in adolescents independent of BMI. Cardiorespiratory endurance data were collected on 90 adolescents aged 13-16 years. The 1MRW was administered on an outside track and a laboratory VO2Peak test was conducted using a maximal treadmill protocol. Multiple linear regression was employed to develop the prediction model. Results yielded the following algorithm: VO2Peak = 7.34 × (1MRW speed in m s(-1)) + 0.23 × (age × sex) + 17.75. The New Model displayed a multiple correlation and prediction error of R = 0.81, standard error of the estimate = 4.78 ml kg(-1) · min(-1), with measured VO2Peak and good criterion-referenced (CR) agreement into FITNESSGRAM's Healthy Fitness Zone (Kappa = 0.62; percentage agreement = 84.4%; Φ = 0.62). The New Model was validated using k-fold cross-validation and showed homoscedastic residuals across the range of predicted scores. The omission of BMI did not compromise accuracy of the model. In conclusion, the New Model displayed good predictive accuracy and good CR agreement with measured VO2Peak in adolescents aged 13-16 years.

Non-high-density lipoprotein cholesterol: distribution and prevalence of high serum levels in children and adolescents: United States National Health and Nutrition Examination Surveys, 2005-2010

OBJECTIVES

To estimate age-related changes for serum concentration of non-high-density lipoprotein cholesterol (HDL-C), describe non-HDL-C distribution, and examine the prevalence of high non-HDL-C levels in children and adolescents by demographic characteristics and weight status.

STUDY DESIGN

Data from 7058 participants ages 6-19 years in the 2005-2010 National Health and Nutrition Examination Surveys were analyzed. A high level of non-HDL-C was defined as a non-HDL-C value ≥ 145 mg/dL.

RESULTS

Locally weighted scatterplot smoothing-smoothed curves showed that non-HDL-C levels increased from 101 mg/dL at age 6 to 111 mg/dL at age 10, decreased to 101 mg/dL at age 14, and then increased to 122 mg/dL at age 19 in non-Hispanic white males. Non-HDL-C levels generally were greater in female than male subjects, lower in non-Hispanic black subjects, and similar in male and slightly lower in female Mexican American subjects, compared with non-Hispanic white subjects. The overall mean was 108 (SE 0.5), and the percentiles were 67 (5th), 74 (10th), 87 (25th), 104 (50th), 123 (75th), 145 (90th), and 158 (95th) mg/dL. Mean and percentiles were greater among age groups 9-11 and 17-19 years than others and greater among non-Hispanic white than non-Hispanic black subjects. The prevalence of high non-HDL-C was 11.8% (95% CI 9.9%-14.0%) and 15.0% (95% CI 12.9%-17.3%) for the age groups 9-11 and 17-19, respectively. It varied significantly by race/ethnicity and overweight/obesity status.

CONCLUSION

Non-HDL-C levels vary by age, sex, race/ethnicity, and weight classification status. Evaluation of non-HDL-C in youth should account for its normal physiologic patterns and variations in demographic characteristics and weight classification.

Hypertension in the teenager

Over the last two decades, essential hypertension has become common in adolescents, yet remains under-diagnosed in absence of symptoms. Diagnosis is based on normative percentiles that factor in age, sex and height. Evaluation is more similar to adult essential hypertension than childhood secondary hypertension. Modifiable risk factors such as obesity, sodium consumption and low exercise should be addressed first. Many anti-hypertensive medications now have specific regulatory approval for children. Sports participation need not be limited in mild or well-controlled cases. Primary care physicians play an important role in reduction of cardiovascular mortality by early detection and referral when needed.

Severe obesity in children and adolescents: identification, associated health risks, and treatment approaches: a scientific statement from the American Heart Association

Severe obesity afflicts between 4% and 6% of all youth in the United States, and the prevalence is increasing. Despite the serious immediate and long-term cardiovascular, metabolic, and other health consequences of severe pediatric obesity, current treatments are limited in effectiveness and lack widespread availability. Lifestyle modification/behavior-based treatment interventions in youth with severe obesity have demonstrated modest improvement in body mass index status, but participants have generally remained severely obese and often regained weight after the conclusion of the treatment programs. The role of medical management is minimal, because only 1 medication is currently approved for the treatment of obesity in adolescents. Bariatric surgery has generally been effective in reducing body mass index and improving cardiovascular and metabolic risk factors; however, reports of long-term outcomes are few, many youth with severe obesity do not qualify for surgery, and access is limited by lack of insurance coverage. To begin to address these challenges, the purposes of this scientific statement are to (1) provide justification for and recommend a standardized definition of severe obesity in children and adolescents; (2) raise awareness of this serious and growing problem by summarizing the current literature in this area in terms of the epidemiology and trends, associated health risks (immediate and long-term), and challenges and shortcomings of currently available treatment options; and (3) highlight areas in need of future research. Innovative behavior-based treatment, minimally invasive procedures, and medications currently under development all need to be evaluated for their efficacy and safety in this group of patients with high medical and psychosocial risks.

Indices of abdominal adiposity and cardiorespiratory fitness test performance in middle-school students

BACKGROUND

Previous research suggests that use of BMI as a screening tool to assess health in youth has limitations. Valid alternative measures to assess body composition are needed to accurately identify children who are aerobically fit, which is an indicator of health status. The purpose of this study was to examine the associations between select anthropometric measures and cardiorespiratory fitness test performance in middle-school students.

METHODS

Participants included 134 students (65 boys and 69 girls) recruited from the 6th, 7th, and 8th grades. Anthropometric measures consisted of BMI, waist circumference (WC), waist-to-height ratio (WHtR), and percent body fat estimated from two-site skinfolds (%BF-SKF), as well as the hand-held OMRON BIA device (%BF-BIA). Cardiorespiratory fitness tests included the one-mile run and PACER test. Data were collected on four separate testing days during the students' physical education classes.

RESULTS

There were statistically significant moderate correlations between the %BF estimations, WHtR, and cardiorespiratory fitness test scores in both genders (P < .001). BMI at best only displayed weak correlations with the cardiorespiratory fitness test scores.

CONCLUSIONS

The results suggest that alternative measures such as %BF-SKF, %BF-BIA, and WHtR may be more valid indicators of youth aerobic fitness lending to their preferred use over BMI.

Utility of Childhood BMI in the Prediction of Adulthood Disease: Comparison of National and International References

OBJECTIVE

To determine whether the U.S. Centers for Disease Control and Prevention (CDC; CDC Reference) or International Obesity Task Force (IOTF; IOTF Reference) BMI cut-off points for classifying adiposity status in children are more effective at predicting future health risk.

RESEARCH METHODS AND PROCEDURES

The sample (N=1709) included 4- to 15-year-old (at baseline) boys and girls from the Bogalusa Heart Study. Overweight and obesity status were determined using both the CDC Reference and IOTF Reference BMI cut-off points at baseline. The ability of childhood overweight and obesity, determined from the two BMI classification systems, to predict obesity and metabolic disorders in young adulthood (after a 13- to 24-year follow-up) was then compared.

RESULTS

Independently of the classification system employed to determine adiposity based on childhood BMI, the odds of being obese and having all of the metabolic disorders in young adulthood were significantly (p<0.05) higher in the overweight and obese groups by comparison with the nonoverweight groups. Childhood overweight and obesity, determined by both the CDC Reference and IOTF Reference, had a low sensitivity and a high specificity for predicting obesity and metabolic disorders in young adulthood. Overweight and obesity as determined by the CDC Reference were slightly more sensitive and slightly less specific than the corresponding values based on the IOTF Reference.

DISCUSSION

Overweight and obesity during childhood, as determined by both the CDC and IOTF BMI cut-off points, are strong predictors of obesity and coronary heart disease risk factors in young adulthood. The differences in the predictive capacity of the CDC Reference and IOTF Reference are, however, minimal.

[Prevalence of obesity in school children in Ivory Coast]

BACKGROUND

According to the World Health Organization, an increased prevalence of hypertension in children is observed since several years due to an epidemic of childhood obesity. What is the extent of this epidemic in our African context?

METHOD

We conducted a prospective descriptive study of pupils encountered in primary and secondary schools of the district of Abidjan from May 3 to June 1st 2010. A sample of 2038 pupils aged 6 to 18 years was randomly selected. Overweight in pupils was assessed by body mass index (BMI).

RESULTS

There were 1182 girls (58%) and 856 boys (42%) whose average age was 12.7±3.6 years. The average weight was 42.6kg±16 (range 14.6 to 106.2kg), the average size was 1.48m±0.19 (range 1 to 1.95m). BMI was 17.2kg/m(2)±3.7 (range 14.6-35.7). The prevalence of obesity was of 5%. In addition, 4% of the students were overweight, 39% extremely thin, 25% thin and 27% normal. Obesity was more common in girls (6.8%) than boys (1.8%). The prevalence of obesity in hypertensives was 16%. BMI influenced the systolic and diastolic blood pressure in both sexes (P<0.001 in both cases).

CONCLUSION

Childhood obesity exists in a country like the Ivory Coast where wealthness is far from generalized. A well-organized management of childhood obesity is necessary to avoid complications such as hypertension.

Childhood obesity and cardiovascular disease

Childhood obesity has reached epidemic proportions. Many of these children have risk factors for later disease, including cardiovascular disease. For optimal cardiovascular health, health care professionals must be able to identify children and youth at risk and provide appropriate support as needed. The present article reviews the current medical literature on obesity and cardiovascular disease risk factors in the paediatric population, the long-term cardiovascular consequences of childhood obesity and the importance of early life. Recommendations promoting optimal cardiovascular health in all children and youth are discussed.

Associations of BMI and its fat-free and fat components with blood lipids in children: Project HeartBeat!

AIM: This study aimed to distinguish between the roles of the two components of BMI, the fat mass (FM) index and the fat-free mass (FFM) index, in BMI's association with blood lipids in children and adolescents. METHODS: A total of 678 children (49.1% female, 79.9% non-black), initially aged 8, 11 and 14 years, were followed at 4-month intervals for up to 4 years (1991-1995). Total cholesterol (TC), LDL-C, HDL-C and triglycerides were determined in fasting blood samples. FFM index and FM index were calculated as FFM (kg)/height (m)(2) and FM (kg)/height (m)(2), respectively. Using a multilevel linear model, repeated measurements of blood lipids were regressed on concurrent measures of BMI or its components, adjusting for age, sex and race and, in a subsample, also for physical activity, energy intake and sexual maturity. RESULTS: Estimated regression coefficients for the relations of TC with BMI, FFM index and FM index were 1.539, -0.606 (p > 0.05) and 3.649, respectively. When FFM index and FM index were entered into the TC model simultaneously, regression coefficients were -0.855 and 3.743, respectively. An increase in BMI was related to an increase in TC; however, an equivalent increase in FM index was related to a greater increase in TC and, when FFM index was tested alone or with FM index, an increase in FFM index was related to a decrease in TC. Similar results were observed for LDL-C. FFM index and FM index were both inversely related to HDL-C and directly to triglycerides. Compared with FFM index, the equivalent increase in FM index showed a greater decrease in HDL-C. CONCLUSION: Greater BMI was related to adverse levels of blood lipids in children and adolescents, which was mainly attributable to BMI's fat component. It is important to identify weight management strategies to halt the childhood obesity epidemic and subsequently prevent heart disease in adulthood.

[Classic and emergent cardiovascular risk factors in schoolchildren in Asturias]

INTRODUCTION

Classic cardiovascular risk factors are present in infancy. C-reactive protein, leptin and adiponectin are the most important inflammatory cardiovascular risk markers.

PATIENTS AND METHODS

A descriptive, cross-sectional study, including children aged 6-12 years old from two local primary schools in the city of Avilés. Body measurements were made to determine the prevalence of obesity and overweight. Systolic and diastolic blood pressure was measured and the presence of metabolic syndrome was determined. Family income, dietary, and life-style habits were collected using the questionnaires GRAFFAR, KIDMED and Self-report instruments for measuring physical activity, respectively. Blood analysis included lipid profile, insulin resistance profile, liver profile, C-reactive protein, leptin and adiponectin.

RESULTS

A total of 459 schoolchildren were included of whom 31% were overweight and 10.9% were obese. Obese children were heavier with higher levels of body mass index, waist circumference, blood pressure, C- reactive protein, leptin, and lower levels of HDL-cholesterol and apolipoprotein A than non-obese children. No differences were found in physical and sedentary activities, but obese children had a worse quality diet than non-obese children.

CONCLUSIONS

Prevalence of obesity and overweight is reaching worrying levels in school age children. Obesity is associated with other classic and inflammatory cardiovascular risk factors. Obese children have a worse quality diet, although they do not do any less physical activities or any more sedentary than non-obese children.

Eating behaviors of children in the context of their family environment

Both a family history of obesity and early childhood obesity have been identified as strong predictors of adult obesity risk. The finding that parental obesity, maternal obesity in particular, increases a child's risk for developing obesity suggests that either shared genes, or environment, or likely a combination of both may promote overeating and excessive weight gain in children. Parents not only create food environments for children's early experiences with food and eating, but they also influence their children's eating by modeling their own eating behaviors, taste preferences, and food choices. Thus, it is important to identify intermediary behavioral eating traits which promote overeating and obesity in children and to determine the extent to which associations between eating traits and excessive weight gain in children may be influenced by genetic factors, environmental factors, or both. Behavioral genetic methods can be used to help partition genetic and environmental sources of variability in behavioral traits. The focus of this paper is to review and discuss findings from both short-term experimental and prospective cohort studies on eating behaviors of children at various stages in their lives. Select child eating traits and parent-child resemblances in eating will be further examined in the context of children's home environment and their familial predisposition to obesity. The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009.

Socio-economic position and adiposity among children and their parents in the Republic of Belarus

BACKGROUND

Socio-economic differences in the prevalence of overweight/obesity may be one factor through which health inequalities arise and may vary by the population studied.

METHODS

Analysing a cohort of 13 889 children born in Belarus between June 1996 and December 1997, the authors investigated associations of parental educational attainment and highest household occupation with: (i) measured body mass index (BMI), waist circumference and skinfold thicknesses at age 6.5 years and (ii) the parents' reported BMI.

RESULTS

Overall, 10% of children, 37% of mothers and 53% of fathers were either overweight or obese. Children from non-manual households were 27% [95% confidence interval (CI): 10%, 47%] more likely to be overweight/obese (based on BMI) than those from manual households. They also had larger waist circumferences and higher percentage body fat (calculated from subscapular and triceps skinfolds). Similar associations for being overweight/obese were seen for fathers [odds ratio (OR), 1.10; 95% CI: 1.02, 1.18], but mothers from non-manual households were less likely to be overweight/obese: (OR, 0.84; 95% CI: 0.79, 0. 90). Associations of childhood and parental overweight/obesity with higher educational status of either parent were similar to those observed for non-manual households.

CONCLUSION

We observed socio-economic differentials in overweight/obesity prevalence among children and their parents in Belarus. More affluent children and their fathers were more likely to be overweight/obese but the reverse was found for mothers.

Adiposity is inversely related to insulin sensitivity in relatively lean Chinese adolescents: a population-based twin study

BACKGROUND

Adolescence is a critical period for rising adiposity and falling insulin sensitivity (IS), but the independent relation between adiposity and IS remains understudied.

OBJECTIVE

The objective was to examine which adiposity measures are most strongly associated with IS in nondiabetic adolescents, whether sex-difference exists, and to what degree genetic or environmental factors affect the adiposity-IS relation.

DESIGN

The study included 1613 rural Chinese adolescents (888 males) aged 13-20 y from a population-based twin cohort. We used graphic plots and linear mixed models to examine the relation of anthropometric and dual-energy X-ray absorptiometry-based measures of adiposity with IS [QUantitative Insulin-sensitivity ChecK Index (QUICKI), fasting serum insulin (FSI), homeostasis model assessment of insulin resistance (HOMA-IR)] and structural equation models to estimate genetic/environmental influences on these associations.

RESULTS

In graphic analyses, participants in the highest quintile (quintile 5) of waist circumference (WC) and percentage body fat (%BF) had the lowest QUICKI and the highest FSI and HOMA-IR values for all age-sex groups. In regression models adjusted for age, Tanner stage, zygosity, and physical activity, all adiposity measures showed inverse associations with IS in both sexes, but WC explained the largest fraction of variance in IS measures (10-14%). Of the phenotypic correlations between adiposity measures and IS (-0.28 to -0.38), 74-85% were attributed to shared genetic factors and 15-26% to common unique environmental factors in both sexes.

CONCLUSIONS

In these relatively lean Chinese adolescents, WC and %BF (quintile 5) are the adiposity measures most consistently and strongly associated with decreased IS in both sexes. To a large degree, shared genetic factors contribute to this association.

Reference curves for triceps and subscapular skinfold thicknesses in US children and adolescents

BACKGROUND

Skinfold thicknesses have long been considered important and valid measurements of subcutaneous fat. Nevertheless, there are no current skinfold reference data for US children and adolescents.

OBJECTIVE

We developed new percentile reference curves for triceps and subscapular skinfold thicknesses by using the same national samples as those included in the reference curves for body mass index (BMI) in the Centers for Disease Control and Prevention 2000 Growth Charts.

DESIGN

We included triceps and subscapular skinfold-thickness measurements for 32,783 individuals who also had complete data for BMI. The LMS method was used to derive 10 smoothed skinfold-thickness percentile reference curves and to generate the L, M, and S parameters that allow the calculation of standardized z scores.

RESULTS

The new reference curves exhibit established age- and sex-related patterns of development, including dramatic prepubescent increases in subcutaneous fatness in boys at the highest percentiles. Comparisons of smoothed medians for race-ethnicity groups confirm greater subcutaneous fatness in white children than in black age mates at the triceps site but similar median subscapular skinfold thicknesses. Median skinfold thicknesses for children considered overweight (> or =85th percentile) or obese (> or =95th percentile) on the basis of BMI cutoffs do not follow closely the skinfold percentile reference channels across age, especially in boys, which suggests a certain degree of independence between BMI and skinfold thickness at the upper extremes of the BMI distribution.

CONCLUSIONS

The age- and sex-standardized skinfold percentiles and z scores will be appropriate for a wide range of research applications that consider measures of subcutaneous fat. Because they were developed by using the same children as those used for the 2000 BMI curves of the Centers for Disease Control and Prevention, they provide an important new complementary assessment tool that should be appropriate for almost all US children and adolescents.

Prevention of overweight and obesity in children under the age of 6 years

Although obesity was rarely observed among children 30 years ago, it is now evident among Canadian children of all ages. Currently, 15.2% of 2- to 5-year-old children are overweight, whereas 6.3% are obese. Limited data suggest that poor dietary and physical activity patterns are increasing obesity risk among these young children. Body weight and lifestyle behaviours are known to track from childhood to adulthood, thereby increasing the risk for obesity and other chronic diseases later in life. Intrauterine life, infancy, and the preschool years may all include critical periods that program the long-term regulation of energy balance, and therefore obesity-prevention strategies should be initiated in utero and continue throughout childhood and adolescence. Although single-strategy obesity-prevention initiatives have had limited success, programs that target multiple behaviours may help reduce body weight and body fat among young children. Parental involvement is key to the success of obesity-prevention programs at a young age, as parents have primary control over their children's food and activity environments. Accordingly, parental obesity is the best predictor of childhood obesity. Parents should be encouraged to teach and role model healthy lifestyle behaviours for their young children. Health professionals can also be involved in obesity prevention, as they are ideally placed to identify young children at risk for obesity. By calculating and plotting the body mass index for all children, and initiating obesity-prevention strategies in utero, health professionals can help curb the rise in overweight and obesity among young children.

Blood lipids in children: age-related patterns and association with body-fat indices: Project HeartBeat!

BACKGROUND

Longitudinal data on the normal development of blood lipids and its relationships with body fatness in children and adolescents are limited. Objectives of the current analysis were to estimate trajectories related to age for four blood lipid components and to examine the impact of change in body fatness on blood lipid levels, comparing estimated effects among adiposity indices, in children and adolescents.

METHODS

Three cohorts, with a total of 678 children (49.1% female, 79.9% nonblack) initially aged 8, 11, and 14 years, were followed at 4-month intervals (1991-1995). Total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels were determined in blood samples taken following fasting. Body fatness was measured by five adiposity indices-BMI; percent body fat (PBF); abdominal circumference; and the sums of six and of two skinfold thicknesses. Trajectories of change in blood lipid levels from ages 8 to 18 years were estimated by gender and race. The impact of change in body fatness on lipid levels was evaluated for each index, adjusting for gender, race, and age.

RESULTS

All lipid components varied significantly with age. Total cholesterol decreased by approximately 19 mg/dL from ages 9 to 16 years in girls and more steeply from ages 10 to 17 years in boys. LDL-C decreased monotonically, more steeply in boys than in girls. It was higher among nonblacks than among blacks. HDL-C increased monotonically in girls, mainly from ages 14 to 18 years, but fluctuated sharply among boys. Levels of HDL-C were higher among blacks than among nonblacks. The levels of triglycerides increased from ages 8 to 12 years among girls and, almost linearly, from ages 8 to 18 years among boys. The levels of triglycerides were higher among nonblacks than among blacks. Increase in body fatness was significantly associated with increases in total cholesterol, LDL-C, and triglyceride levels. Significant interactions between the adiposity indices (except for BMI) and gender indicated smaller impacts of change in body fatness on total cholesterol and LDL-C in girls than in boys. The estimated impact on triglycerides was weaker among blacks than among nonblacks, except for PBF. Change in body fatness was negatively associated with HDL-C. The results remained essentially unchanged after adjustments for energy intake, physical activity, and sexual maturation.

CONCLUSIONS

Patterns of change with age in blood lipid components vary significantly among gender and racial groups. Increase in body fatness among children is consistently associated with adverse change in blood lipids. Evaluation of blood lipid level should take into account variation by age, gender, and race. Intervention through body-fat control should help prevent adverse lipid levels in children and adolescents.

[Hypertension in obese children and adolescents]

Obesity, especially upper body fat distribution, has become an increasingly important medical problem in children and adolescents. Outcomes related to childhood obesity include, as in adult population, hypertension, type 2 diabetes mellitus, dyslipidemia, left ventricular hypertrophy, obstructive sleep apnea, orthopedic and socio-psychological problems. Obese children are at approximately 3-fold higher risk for hypertension from non-obese ones. Obesity-hypertension appears to be characterized by a preponderance of isolated systolic hypertension, increased heart rate and blood pressure variability, increased levels of plasma catecholamine and aldosterone, and salt-sensitivity. Lifestyle changes of weight loss, healthier diet and regular physical exercise are effective in obesity-hypertension control, though pharmacological treatment is frequently necessary. Screening for dyslipidemia and impaired glucose tolerance should be performed in paediatric patients with obese hypertension on regular basis, at least once annually or semiannually to discover metabolic syndrome and to prevent its increased cardiovascular risk. Of course, prevention of obesity is the primary goal.

Cardiovascular Risks Associated With Obesity in Children and Adolescents

Introduction: The aim of this paper is to review the cardiovascular (CVS) risks associated with obesity in children and adolescents. Both short-term and long-term CVS consequences, the mechanisms of how these develop and the measures that can alter or reverse these CVS events are reviewed. Materials and Methods:Selected publications include original articles and review papers that report on studies of CVS risks and consequences related to childhood obesity. Some papers that contain data from adults studies are also included if the contents help to explain some underlying mechanisms or illustrate the continuation of related CVS changes into adulthood. Results: Obese children and adolescents have an increased risk for CVS complications that include elevation of blood pressure, clustering of CVS risk factors (Metabolic Syndrome), changes to arterial wall thickness, elasticity and endothelium, as well as changes in left ventricular structure and function. Some of these cardiovascular problems may be initiated or potentiated by obstructive sleep apnoea that can accompany obesity in children. Many of such changes have been noted to reverse or improve with weight reduction. Conclusions:Early development of CVS risks in obese children and the possible continuation of CVS complications into adulthood have been observed. Obstructive sleep apnoea in obese children can further contribute to such CVS risks. These findings underscore the importance of prevention of childhood obesity as a priority over management of obesity in children. The prevalence of obesity has risen by three-folds or more in many countries since 1980. In 2005, it was estimated that globally there are about 1.6 billion overweight adults and at least 400 million of them are obese. This increase in the prevalence of adults being overweight and obese comes with a heavy price. The cost of healthcare has significantly increased and is expected to increase even more because of the close association between obesity and various chronic diseases. Key words: Endothelial function, Hypertension, Metabolic syndrome, Obstructive sleep apnoea

A Prospective Study of Weight and Metabolic Syndrome in Young Hispanic Children

OBJECTIVE: Examine weight in young Hispanic children over a two-year period; investigate the relationships among overweight, physical activity, caloric intake, and family history in the development of the metabolic syndrome (MS). METHODS: Forty-seven children (ages 5-8) from diverse Hispanic backgrounds recruited from elementary schools were evaluated. Laboratory analyses, anthropometric data, and measures of physical activity and caloric intake were included. RESULTS: The majority of the children were overweight at baseline (66%) and at follow-up (72%). Children who were overweight at baseline were more likely to exhibit MS at follow-up than were those who were not overweight at baseline. CONCLUSIONS: Overweight appears to be an independent predictor of MS among Hispanic children.

Obesity, hypertension, and mental health evaluation in adolescents: a comprehensive approach

The global epidemic of childhood and adolescent obesity in developing and developed countries has become a major public health concern. Given the relation between obesity and hypertension as documented in several landmark studies, it is no surprise that as the prevalence of obesity has increased in the pediatric population, the rates of hypertension have also increased substantially. Hypertension is one of the most important risk factors for cardiovascular diseases and stroke; therefore, evaluation and initiation of appropriate treatment are extremely important in the pediatric population. Evaluation for secondary causes of hypertension, including renovascular, renoparenchymal, and endocrine disease is the approach most commonly used in healthcare settings, with the goal to detect abnormalities that already have or might, if left unrecognized, affect the physical health of the child in the future. Children and adolescents are commonly evaluated for organic disease even in situations in which secondary hypertension is unlikely and overweight or obesity is most likely the primary factor contributing to hypertension. Psychological and psychosocial factors, which may play an important role in the etiology of obesity and related blood pressure elevation, are often addressed inadequately or completely ignored, potentially reducing long-term therapy success and increasing the incidence of avoidable complications. It is proposed that a comprehensive evaluation by a behavioral health provider will improve outcomes and potentially reduce long-term morbidity and hypertension-related end organ disease. A framework for mental health evaluation is provided.

Association of age and sex with cardiovascular risk factors and insulin sensitivity in overweight children and adolescents

To determine the effect of age and sex on cardiovascular risk factor expression in overweight children, data from clinical records of 497 overweight children (2-18 years of age) were examined. Data included average blood pressure (BP), fasting lipids, glucose, and insulin. The sample was stratified by age (younger than 11 and 11 years and older) and analyzed by sex. Subjects with an average BP > or = 90th percentile were classified as having high BP. Insulin and glucose were used in equations to estimate insulin sensitivity. Among subjects 11 years and older (n = 268), 52.6% of males had high BP compared with 32.6% of females (P < .001). Mean high-density lipoprotein cholesterol was lowest in the males 11 years and older compared with the females and younger males (P < .01). Triglyceride levels trended higher in males independent of age. In multivariate analyses, high BP was most strongly associated with age and severity of overweight while triglyceride level was most associated with sex and insulin resistance. The prevalence of high BP and dyslipidemia in overweight children is high. Overweight males 11 years and older have a higher prevalence of high BP and low high-density lipoprotein cholesterol than females and younger males. Greater cardiovascular risk factor expression in overweight males 11 years and older may explain the earlier appearance of cardiovascular disease end points in overweight men.

Weight loss in obese African American and Caucasian adolescents: secondary analysis of a randomized clinical trial of behavioral therapy plus sibutramine

BACKGROUND

Obesity, a major risk factor for cardiovascular disease, is more prevalent in African American adolescents than in their Caucasian counterparts. Effective weight loss treatment options are required to aid in the reduction of this health disparity. The purpose of this study, a secondary analysis of data collected as part of a double-blind, randomized clinical trial of behavioral and pharmacologic weight loss, was to examine and compare changes in weight loss and cardiometabolic risk factors in African American and Caucasian adolescents.

METHODS

Analysis included 34 African American and 45 Caucasian obese boys and postmenarcheal girls. The participants were randomized to family-based behavioral therapy plus placebo or family-based behavioral therapy plus sibutramine. Changes in weight, body mass index, % body mass index, fasting glucose, insulin, homeostatically assessed insulin resistance, and lipid levels were measured at baseline and month 6.

RESULTS

Mean age was 14.1 years (range 13-17 years). Average body mass index was 37.8 kg/m (32-44). Retention was 88.2% for African American adolescents and 91% for Caucasian adolescents. At baseline, African American adolescents had lower waist circumferences, triglycerides, serum glucose, and higher high-density lipoprotein cholesterol levels. At month 6, percent change in body mass index and weight loss was significantly greater in the Caucasian drug group than in placebo, whereas the weight loss for African Americans in the drug group versus those in the placebo group was not significant but had a medium effect size (Cohen d = 0.64). Irrespective of treatment group, those losing >5% of initial BMI had significant reductions in waist circumference. Caucasians had significant reductions in triglycerides, high-density lipoprotein cholesterol, glucose, insulin, and homeostatically assessed insulin resistance levels; African American responders had significant reductions in triglycerides, insulin, and homeostatically assessed insulin resistance.

CONCLUSION

Sibutramine impacted reductions in weight loss in both African American and Caucasian teens. Weight loss, whether by behavioral therapy alone or in combination with pharmacotherapy, produced beneficial changes in cardiometabolic risk factors in adolescents from both racial groups. Limitations included a small sample size. Longer-term obesity intervention studies addressing retention, acceptability, safety, and treatment effect on cardiometabolic risk are critical to reducing health disparities.

Dietary patterns are associated with sexual maturation in Korean children

The purpose of this study was to investigate the association between dietary patterns and sexual maturation among Korean children. A cross-sectional study was conducted in 422 boys and 365 girls aged 9–12 years living in Seoul, Korea. Three-day food records were obtained, and pubertal stages were determined with a questionnaire using Tanner stages. Body fat was measured by bioelectrical impedance analysis, and bone mass content at the right calcaneus was measured by portable dual-emission X-ray absorptiometry. Exploratory factor analysis with a Varimax rotation was applied to identify dietary patterns using twenty-four food groups. Four distinct dietary patterns – ‘rice and Kimchi’, ‘shellfish and processed meat’, ‘pizza and drinks’ and ‘milk and cereal’ – were obtained. Twenty-six per cent (24% stage 2, 2% stage 3) of boys had genital development, and 79% (63% stage 2, 16% stage 3) of girls showed breast development. In boys, genital development was weakly positively associated with ‘shellfish and processed meat’ dietary factor scores (odds ratio 1·65, CI 0·95, 2·89,pfor trend 0·07) after adjusting for confounders. In girls, breast development was significantly positively associated with the factor score of ‘shellfish and processed meat’ (odds ratio 1·88, CI 1·08, 3·26,pfor trend 0·05). These results suggest that dietary patterns were related to body composition and sexual maturation among the Korean children. Further investigations are needed to identify components of the foods consumed in high amounts in these patterns and how they are related to sexual maturation.

Childhood Obesity

The prevalence of child and adolescent obesity has increased dramatically in the last 20 years and has led to a rise in cardiovascular-related comorbidities, including type 2 diabetes, in children and youth. The American Heart Association (AHA) issued a scientific statement with available evidence and guidance for health professionals involved in the prevention and management of childhood obesity. The scientific statement was ranked as 1 of the Top 10 Research Advances of 2005 by the AHA. This article builds on the scientific statement, presents multilevel determinants, and emphasizes individual and population-based approaches to prevention. Treatment of child and youth obesity, along with the implications for nurses and other health professionals, is also included.

Promoting Cardiovascular Health in Children and Adolescents

Data accumulated over the past 3 decades indicate that cardiovascular disease processes are accelerated over the life course by potentially modifiable risk factors and environmental exposures. Based on available evidence, the American Heart Association and other pediatric agencies issued scientific statements and guidelines with recommendations for promoting the cardiovascular health of children and adolescents and for identifying and managing children at risk for cardiovascular disease. This article presents an overview of the evidence and emphasizes current recommendations for population-based and individually oriented approaches to cardiovascular disease prevention in childhood and adolescence.

Modifiable environmental and behavioral determinants of overweight among children and adolescents: report of a workshop

The number of children at risk for overweight and the number of overweight children are increasing and have become a serious public health concern. Interventions that could be applied at the population level have not been proven effective. The development of effective strategies is thought to be hampered by the lack of understanding of which behavioral and environmental factors need to be modified. On June 14 and 15, 2004, the NIH held a meeting of experts to discuss the issue of modifiable determinants of obesity in children and adolescents. Included were presentations on interventions among children that have been proven effective, dietary and physical activity behavioral determinants, physical, social, and family environmental determinants, and the quality of measures of determinants and correlates of overweight.

Aerobic fitness, body mass index, and CVD risk factors among adolescents: the Québec family study

PURPOSE

The purpose of this study was to examine the association of body mass index (BMI) and aerobic fitness on cardiovascular disease (CVD) risk factors in adolescents.

METHODS

The sample included 416 boys and 345 girls 9-18 y of age from the Québec Family Study. Participants were cross-tabulated into four groups using a median split of age-adjusted physical working capacity (PWC) and body mass index (BMI). Group differences in age-adjusted CVD risk factors (blood pressures, fasting total cholesterol (CHOL), LDL -C, HDL-C, HDL/CHOL, triglycerides, glucose, and a composite risk factor score) were examined by two-way ANOVA.

RESULTS

Several CVD risk factors showed significant main effects for PWC, BMI and/or the PWC by BMI interaction. In general, low fit males and females had higher blood lipids and glucose compared to their high fit counterparts within BMI categories although none of the differences reached statistical significance. The high fit/low BMI group showed the best CVD risk factor profile while the low fit/high BMI showed a poorer profile as evidenced by several significant differences between these two groups. Other significant differences occurred for various risk factors between groups.

CONCLUSION

Both aerobic fitness and BMI show an independent association with CVD risk factors in adolescents.

Overweight in children and adolescents: pathophysiology, consequences, prevention, and treatment

The prevalence of overweight among children and adolescents has dramatically increased. There may be vulnerable periods for weight gain during childhood and adolescence that also offer opportunities for prevention of overweight. Overweight in children and adolescents can result in a variety of adverse health outcomes, including type 2 diabetes, obstructive sleep apnea, hypertension, dyslipidemia, and the metabolic syndrome. The best approach to this problem is prevention of abnormal weight gain. Several strategies for prevention are presented. In addition, treatment approaches are presented, including behavioral, pharmacological, and surgical treatment. Childhood and adolescent overweight is one of the most important current public health concerns.

Agrupamiento de factores de riesgo cardiovascular en hijos obesos de padres con hipertensión esencial

INTRODUCTION

The prevalence of obesity in industrialized countries is increasing and is closely related to essential hypertension (EHT) in adolescents.

OBJECTIVE

To analyze the prevalence of obesity and its association with other known cardiovascular risk factors in a sample of children and young adults with at least one parent with EHT.

METHODS

The EHT group consisted 51 children and young adults (28 males [aged 5.4-25.6 years]) with at least one parent with EHT. The control group comprised 73 healthy normotensive children and young adults (43 males [aged 7.2-25.2 years]) who completed the follow-up visits of the RICARDIN study. Blood pressure (BP) was measured with a standardized technique using a mercury sphygmomanometer. A 12-hour fasting blood sample was taken for lipid profile and high sensitivity C-reactive protein (CRP) determinations. Financial support: FIS 03/0350, ESV Foundation Grant, 2003.

RESULTS

The prevalence of obesity was five times higher in the EHT group than in controls (19.6% vs. 4.1%, p = 0.007). In this group, obese subjects showed higher systolic BP (122.0 vs. 110.4 mmHg p = 0.004) and lower high-density lipoprotein cholesterol (HDL-C) levels (47.6 vs. 58.0 mg/dl, p < 0.05). After adjustment for age and systolic BP, obese subjects in the EHT group showed significantly higher CRP values than non-obese subjects in this group (p = 0.024).

CONCLUSIONS

The prevalence of obesity is higher in the offspring of parents with EHT than in non HT-prone subjects. Clustering of other additional risk factors indicates the need for high-risk preventive interventions in this group of children and young adults.

Cardiovascular disorders in the college student

This article provides an overview of diagnosis and treatment of college students with possible congenital or acquired heart problem issues. Preventive cardiac concerns and issues regarding risk factors for atherosclerotic heart disease are discussed. College students with corrected or palliated heart conditions are included because they are an expanding segment of the adult cardiac population. Selected major syndromes with associated cardiac anomalies and complications are included. Finally, reinforcement and review of cardiac diagnosis or management issues occurring in college students (six case scenarios) are included in the appendix.

Prevalence of the insulin resistance syndrome in obesity

AIMS

To assess prevalence of the insulin resistance syndrome (IRS: obesity, abnormal glucose homoeostasis, dyslipidaemia, and hypertension) in obese UK children and adolescents of different ethnicities and to assess whether fasting data is sufficient to identify IRS in childhood obesity.

METHODS

A total of 103 obese (BMI >95th centile) children and adolescents 2-18 years of age referred for assessment underwent an oral glucose tolerance test, measurement of fasting lipids, and blood pressure determination. Main outcome measures were prevalence of components of IRS by modified WHO criteria, with IRS defined as > or =3 components (including obesity).

RESULTS

There were 67 girls (65%). BMI z-score ranged from 1.65 to 6.15, with 72% having a z-score > or =3.0. Abnormal glucose homoeostasis was identified in 46% (hyperinsulinism in 40%, impaired fasting glucose in 0.8%, impaired glucose tolerance in 11%). No subjects had silent type 2 diabetes. Dyslipidaemia was identified in 30% and hypertension in 32%. Thirty one per cent had obesity alone, 36% had two components, 28% had three, and 5% had all four components. Birth weight, BMI, and family history of IRS were not associated with risk of IRS. Higher age increased the risk of IRS; however the syndrome was seen in 30% of children under 12 years. The use of fasting glucose and insulin data for identifying IRS had a sensitivity of 88% and specificity of 100%.

CONCLUSIONS

One third of obese children and adolescents have the IRS; however type 2 diabetes is rare. Obese children with the IRS may form a high risk group to whom scarce intervention resources should be targeted. Further work is needed to develop appropriate screening programmes for IRS components in significantly obese children.

Ponderal gain, waist-to-hip ratio, and pubertal development in girls with type-1 diabetes mellitus

OBJECTIVES

We assessed pubertal development, height, weight, and waist-to-hip ratio (WHR), an index of central adiposity during puberty, in girls with type-1 diabetes mellitus (T1DM), compared to a contemporary control group.

METHODS

Pubertal development, weight, height and WHR were studied in 100 pubertal girls with T1DM, and were compared to a control group of 576 normal girls (C), recruited from schools with a similar socioeconomic level and ethnicity. The age of onset of various pubertal stages was estimated by using probit analysis.

RESULTS

Breast Tanner stage 2 (BT2) began at 8.89 +/- 0.11 and 9.10 +/- 0.28 yr in C and T1DM, respectively. A delay of 6 months was observed in T1DM for BT3 and BT4 (p < 0.05). Menarche occurred 6 months later in girls with T1DM (p = 0.03). WHR decreased during puberty in C (p < 0.001), but not in T1DM. In girls with T1DM, the body mass index standard deviation score (BMI-SDS) increased throughout puberty (p < 0.001), but it was stable in C. In T1DM girls, BMI-SDS, but not hemoglobin A1c levels (HbA1c), was a significant determinant of pubertal development. Final height was similar in T1DM and C.

CONCLUSIONS

Pubertal development in girls with T1DM occurred earlier than described in historical cohorts, but a later onset of menarche and final stages of breast development were observed. The increase in BMI-SDS and the stability of WHR in girls with T1DM during puberty suggest that this period may be critical for determining later weight gain and body composition in adult women with this condition.

The current epidemic of childhood obesity and its implications for future coronary heart disease

This article acquaints readers with the data sources documenting the dramatic increases of overweight and obesity in the United States in the past 40 years, explains the reference standards for ascertaining measures of overweight in adults and children, and cites evidence that establishes obesity as a risk factor for premature death. Also reviewed are reports documenting recent increases in the frequency of type 2 diabetes mellitus and glucose intolerance and selected reports emanating from four longitudinal studies performed in large populations of adults, children, and adolescents linking excessive adiposity to coronary heart disease risk factors. A brief discussion of the challenges that pediatricians and other primary care health providers face in helping to diminish the prevalence of obesity and its attendant health problems is presented.

Ethnic differences in the prevalence of overweight among young children in Hawaii

OBJECTIVES

To compare the prevalence of overweight among young children of different ethnic backgrounds and describe the age pattern of overweight in early childhood.

METHODS

Cross-sectional study of 21,911 children, 12 to 59 months old, participating in the Hawaii Special Supplemental Nutrition Program for Women, Infants, and Children in 1997-1998. They were grouped in eight ethnic categories. For 1-year-olds we defined overweight as weight-for-age at the 95th percentile or more and underweight as weight-for-age at less than the 10th percentile. For 2- to 4-year-olds overweight was defined as body mass index (BMI) at the 95th percentile or more, underweight as BMI less than 10th percentile, tall stature as height-for-age at the 95th percentile or more, and short stature as height-for-age at less than the 10th percentile. The National Center for Health Statistics 2000 growth charts were the reference values. The analysis included bivariate and multivariate methods.

RESULTS

Large differences were found among ethnic groups. Among 1-year-olds, Samoans were the heaviest (17.5% overweight) and Filipinos the lightest (30.2% underweight). Among 2- to 4-year-olds, Samoans were the heaviest (27.0% overweight) and the tallest (16.9% tall), whereas Asians were the lightest (12.2% underweight), and Filipinos the shortest (19.0% short). Hawaiians and Asians also had a high percentage of short children (13.6% and 12.2%, respectively). Prevalence of overweight in all 2- to 4-year-olds was more than the expected 5%, especially for Samoans, Filipinos, Hawaiians, and Asians. At age 2 to 4 years, overweight was almost twice as prevalent as at age 1. Multivariate analysis showed that ethnicity (Samoan) had the strongest independent association with weight-for-age percentile, BMI, and overweight in the two age groups, followed by birth weight.

CONCLUSIONS

This is the first study of overweight among children of Asian and Pacific Island backgrounds in Hawaii. It identified important characteristics of growth and will be helpful in the design of appropriate activities to prevent overweight.

Sensitivity and specificity of classification systems for fatness in adolescents

BACKGROUND

Various body mass index (BMI) standards have been proposed for defining overweight in adolescence, but few studies have evaluated their diagnostic accuracy.

OBJECTIVE

We compared the sensitivity and specificity of BMI-based classification systems for detecting excess fatness in adolescents.

DESIGN

A cross-sectional analysis of 474 adolescents aged 17 y was used. Body composition was measured by using densitometry. The international BMI-based systems recommended by the International Obesity Task Force and the World Health Organization were evaluated on the basis of their sensitivity and specificity for detecting excess body fat. Receiver operating characteristic analysis was performed to derive cutoffs to maximize the sum of sensitivity and specificity. True positives were defined by using the percentage body fat cutoffs proposed by Williams et al (Am J Public Health 1992;82:358-63).

RESULTS

For both classification systems, the specificity for overweight was high for both sexes (0.95-1.00). The sensitivity was fairly high for the males (0.72-0.84) but was very low for the females (0.22-0.25). For the males, a BMI cutoff equal to the 85th percentile on a Swedish BMI reference chart maximized the sum of sensitivity and specificity while having both high sensitivity (0.92) and high specificity (0.92). For the females, larger tradeoffs in specificity were needed to improve sensitivity. The mean (+/-SE) areas under the receiver operating characteristic curves for the males and the females were 0.97 +/- 0.02 and 0.85 +/- 0.02, respectively.

CONCLUSIONS

Recommended international classification systems have very high specificity, which results in few cases of non-overweight adolescents being mislabeled as overweight. However, the sensitivity is very low in female adolescents. Thus, many overweight female adolescents could be missed in intervention programs that use the proposed international BMI cutoffs as selection criteria.

Body mass index, waist circumference, and clustering of cardiovascular disease risk factors in a biracial sample of children and adolescents

OBJECTIVE

To derive optimal body mass index (BMI) and waist circumference thresholds for children and adolescents, to predict risk factor clustering.

DESIGN

Cross-sectional receiver operating characteristic curve analysis.

SETTING

The Bogalusa Heart Study, a community-based study of cardiovascular disease risk factors in early life.

PARTICIPANTS

A total of 2597 black and white children and adolescents, 5 to 18 years of age, who were examined between 1992 and 1994.

MAIN OUTCOME MEASURES

The presence or absence of > or =3 age-adjusted risk factors (low high-density lipoprotein cholesterol level, high low-density lipoprotein cholesterol level, high triglyceride level, high glucose level, high insulin level, and high blood pressure) was predicted from age-adjusted BMI and waist circumference values.

RESULTS

The areas under the receiver operating characteristic curves were significantly different from 0.5 for both BMI and waist circumference for all gender/race groups, ranging from 0.73 to 0.82. The optimal BMI thresholds were at the 53rd and 50th percentiles for white and black male subjects, respectively, and at the 57th and 51st percentiles for white and black female subjects, respectively. Similarly, the optimal waist circumference thresholds were at the 56th and 50th percentiles for white and black male subjects, respectively, and at the 57th and 52nd percentiles for white and black female subjects, respectively. The sensitivity and specificity at the thresholds were similar for all gender/race groups, ranging from 67% to 75%.

CONCLUSIONS

The use of BMI and waist circumference for the prediction of risk factor clustering among children and adolescents has significant clinical utility. In this sample, race and gender differences in the optimal thresholds were minimal.

Discrepancies between classification systems of childhood obesity

Despite growing concern about weight-related problems among children, no universally accepted classification system for childhood obesity exists. There is a number of proposed international body mass index (BMI)-based systems in use and national variants also exist in many countries. The absence of a universally accepted standard and confusion concerning which classification system to use on national levels complicate monitoring of the development of the obesity epidemic, stratification for selective interventions in public health, screening in clinical practice and comparisons between studies. Some proposed international classification systems have not only been recommended for global monitoring and comparisons between studies, but also for clinical and national epidemiological use in some countries. Possible discrepancies may thereby lead to inefficiencies in health care delivery and prevention programmes. The problems associated with misclassification of individuals at risk may lead to overconsumption of health care resources by lower-risk individuals and underconsumption by higher-risk individuals, which is costly both in terms of foregone health improvements and in terms of wasteful monetary usage. The aim of this paper was to review the specific problems associated with BMI as a measure of adiposity in childhood, the most commonly used classification systems for childhood obesity based on BMI, and how their performance can be evaluated.

Population-specific alleles: the polymorphism (K121Q) of the human glycoprotein PC-1 gene is strongly associated with race but not with insulin resistance in black and white children

The K121Q polymorphism of the glycoprotein PC-1 gene was recently reported to associate with insulin resistance (IR) in an all-Caucasian, Sicilian population. Given black-white differences in plasma insulin and IR, we compared the prevalence of the KK, KQ, and QQ genotypes and their associations with insulin and IR in 2 large, biracial pediatric samples: 1 hospital-based (n = 301, 137 blacks and 164 whites) and 1 school-based (n = 639, 344 blacks and 295 whites). The Q allele frequencies in the hospital-based and school-based cohorts in black children were 0.80 and 0.77 and in the white children, 0.15 and 0.13. The K allele frequencies in the hospital-based and school-based cohorts in black children were 0.20 and 0.23 and in the white children, 0.85 and 0.87. Differences in allelic frequencies were highly significant (chi square test, P <.0001) for both the hospital-based cohort and the school-based cohort. Both cohorts were in Hardy-Weinberg equilibrium. Within race, after covariance adjusting for age and body mass index (BMI), there were no significant differences (P >/=.10) among the 3 PC-1 genotypes for insulin, glucose, or homeostasis model assessment (HOMA) IR. After covariance adjusting for age and BMI, black girls had higher insulin (P =.0007) and higher HOMA IR (P =.0002) than white girls. The K121Q polymorphism was not associated with insulin, glucose, or HOMA IR measures in black or white children. However, the QQ genotype was population-specific, encompassing most black children versus 1% to 3% of white children. As such, K121Q genotyping should be useful in epidemiology, population genetics, and forensic anthropology.