Sex and race differences in cardiovascular disease risk factor changes in schoolchildren, 1975-1990: the Princeton School Study

A Community-Based Physical Education and Activity Intervention for African American Preadolescent Girls: A Strategy to Reduce Racial Disparities in Health

Physical activity habits fostered and developed early in life tend to persist into adulthood, reducing the incidence of chronic diseases associated with a sedentary lifestyle in later life. This is of particular importance for racial and ethnic minority populations who experience significant disparities in rates of chronic disease. Thus, promoting physical activity in minority children is an effective strategy for reducing these health disparities. Unfortunately, however, recommendations for effective implementation of such programs are sorely lacking. This article describes the development and implementation of Lively Ladies, a physical education and activity intervention targeted to low-income, preadolescent, African American girls in a community-based youth services organization. Low-income, minority girls face the catch-22 situation of being at higher risk for physical inactivity while having limited or no access to physical fitness programs. This article demonstrates that community-based youth organizations can play an important role in changing this situation. The authors’ experience with Lively Ladies indicates the effectiveness of a theory-based program addressing modifiable psychosocial and environmental determinants of behavior. They provide recommendations to guide future design and implementation of community-based physical education and activity interventions for a population group that tends to have increased risk for physical inactivity and limited access to fitness programs and facilities.

Comparative Effectiveness Research Through a Collaborative Electronic Reporting Consortium

The United States lacks a system to use routinely collected electronic health record (EHR) clinical data to conduct comparative effectiveness research (CER) on pediatric drug therapeutics and other child health topics. This Special Article describes the creation and details of a network of EHR networks devised to use clinical data in EHRs for conducting CER, led by the American Academy of Pediatrics Pediatric Research in Office Settings (PROS). To achieve this goal, PROS has linked data from its own EHR-based "ePROS" network with data from independent practices and health systems across the United States. Beginning with 4 of proof-of-concept retrospective CER studies on psychotropic and asthma medication use and side effects with a planned full-scale prospective CER study on treatment of pediatric hypertension, the Comparative Effectiveness Research Through Collaborative Electronic Reporting (CER(2)) collaborators are developing a platform to advance the methodology of pediatric pharmacoepidemiology. CER(2) will provide a resource for future CER studies in pediatric drug therapeutics and other child health topics. This article outlines the vision for and present composition of this network, governance, and challenges and opportunities for using the network to advance child health and health care. The goal of this network is to engage child health researchers from around the United States in participating in collaborative research using the CER(2) database.

Obesity and arterial hypertension in schoolchildren from Santa Cruz do Sul--RS, Brazil

OBJECTIVE

To verify the prevalence of obesity and hypertension in schoolchildren from Santa Cruz do Sul - RS, Brazil, in 2005 and 2008.

METHOD

The study was performed with two consecutive cross-sectional measurements, consisting of a stratified cluster sample, totaling 414 students, aged between 7 and 17 years, of which 215 (51.9%) were males and 199 (48.1%) were females. Obesity was assessed by body mass index (BMI) and percentage of body fat (%BF). Hypertension was measured by blood pressure values, both systolic (SBP) and diastolic (DBP).

RESULTS

BMI assessment showed 18.6% and 22.3% of excess weight in males and 22.6% and 14.6% in females (in 2005 and 2008, respectively). Regarding obesity, the prevalence was 4.7% in both years for males and a reduction from 12.6% to 9.0% was observed in females. When analyzing the difference between assessments, there was significance in the BMI classification (p = 0.022) and %BF (p = 0.017) only in females. Statistically significant changes in SBP were found only in males (p < 0.001).

CONCLUSION

The levels of excess weight, obesity, and %BF in females, as well as the increased levels of systolic blood pressure in males, demonstrate the need for early intervention through more effective public health campaigns.

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.

Secular trends in BMI and blood pressure among children and adolescents: the Bogalusa Heart Study

OBJECTIVE

The prevalence of obesity among children and adolescents increased by almost threefold from the 1970s to 2000. We examined whether these secular changes in BMI were accompanied by increases in blood pressure levels.

METHODS

A total of 24,092 examinations were conducted among 11,478 children and adolescents (aged 5-17 years) from 1974 to 1993 in the Bogalusa Heart Study (Louisiana).

RESULTS

The prevalence of obesity increased from 6% to 17% during this period. In contrast, only small changes were observed in levels of systolic blood pressure (SBP) and diastolic blood pressure (DBP), and neither mean nor high (based on the 90th percentile from the Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents) levels increased over the 20-year period. Within each race-gender group, mean levels of SBP did not change, whereas mean levels of DBP decreased by 2 mm Hg (P < .001 for trend). Levels of BMI were positively associated with levels of SBP and DBP within each of the 7 examinations, and controlling for BMI (along with other covariates) indicated that only ~60% as many children as expected had high levels of blood pressure in 1993.

CONCLUSIONS

Our finding that levels of DBP and SBP among children in this large sample did not increase despite the increases that were seen in obesity indicates that changes in blood pressure levels in a population do not necessarily parallel changes in obesity. Additional study of the potential characteristics that have ameliorated the expected increase in high blood pressure could lead to further reductions in risk.

Valsartan: in children and adolescents with hypertension

Valsartan is an oral angiotensin II subtype 1 receptor antagonist with well established antihypertensive efficacy in adults. It is now approved in the EU and the US for the treatment of hypertension in children and adolescents. In two, randomized, double-blind trials, a once-daily regimen of valsartan reduced the blood pressure (BP) of children and adolescents with hypertension. In one trial in hypertensive children and adolescents aged 6-16 years, significant dose-dependent reductions from baseline in mean sitting systolic BP (msSBP) were observed for recipients of valsartan following 2 weeks' treatment (primary endpoint). There were corresponding dose-dependent and significant reductions in mean sitting diastolic BP. Following 2 further weeks of treatment, the reduction in msSBP was maintained in patients who were re-randomized to continue receiving the same dosage of valsartan but not in those re-randomized to placebo. In the other trial in hypertensive children and adolescents aged 6-17 years, valsartan was no less effective than enalapril in reducing BP. Following 12 weeks' treatment, the least square mean reduction from baseline in msSBP (primary endpoint) in recipients of valsartan was noninferior to that in recipients of enalapril. In addition, the proportion of patients achieving an msSBP <95th percentile for age, sex, and height at week 12 was not significantly different between recipients of valsartan and enalapril (67% vs 70%). Treatment with valsartan for up to 52 weeks was well tolerated in children and adolescents with hypertension.

Race, childhood insulin, childhood caloric intake, and class 3 obesity at age 24: 14-year prospective study of schoolgirls

The prevalence of Class 3 obesity (BMI ≥40 kg/m(2)) has more than doubled in the past 25 years. In a 14-year prospective study from age 10 to 24 of a biracial schoolgirl cohort (293 black, 256 white), we assessed childhood correlates of Class 3 BMI at age 24. Of 42 girls with Class 3 BMI at age 24, 36 (86%) were black. By logistic regression, significant explanatory variables of Class 3 BMI at age 24 included top decile waist circumference at age 11 (odds ratio (OR) 5.7, 95% confidence interval (CI) 2.3-13.9, P = 0.0002), age 10 BMI ≥ the Center for Disease Control (CDC) 2000 top 15% (OR 7.0, 95% CI 2.5-19.3, P = 0.0002), and a three-way interaction between race, childhood insulin, and average caloric intake from age 10 to age 19 (for each unit increase, OR 1.7 95% CI 1.3-2.2, P = 0.0003). Age 10 BMI, age 11 waist circumference, and interaction of race, childhood insulin, and childhood caloric intake predict Class 3 obesity in young adulthood, facilitating childhood identification of girls at high risk for developing Class 3 obesity.

Atuação dos pais na prevenção da hipertensão arterial : uma tecnologia educativa em saúde

Pesquisa participante com o objetivo de avaliar as mudanças comportamentais em quinze pais de alunos do pré-escolar na prevenção dos fatores de risco da hipertensão arterial, a partir da aplicação de uma tecnologia educativa em saúde com base no Modelo de Crenças em Saúde, em uma escola privada de Fortaleza-CE. A pesquisa de campo foi realizada por meio de oficinas educativas e a coleta de dados via questionários e entrevistas. Após se organizar os dados em categorias, fundamentou-se a análise nos pressupostos da educação em saúde. Com a aplicação da tecnologia educativa em saúde, constataram-se mudanças significativas nos hábitos dos pais, além dos papéis assumidos agente de mudança e de multiplicador das ações educativas na família. Contudo houve dificuldades no processo de mudança, mas os pais estavam motivados para a prevenção dos fatores de risco da hipertensão arterial em si e nos filhos. Então, essa tecnologia educativa embasada no Modelo de Crenças em Saúde, mostrou-se eficiente, pois ocorreram mudanças comportamentais significativas, bem como motivação dos pais para a prevenção da hipertensão arterial mediante um estilo de vida saudável.

The trend of hypertension and its relationship to the weight status among Taiwanese young adolescents

This study evaluates prevalence of hypertension in 1996 and 2006, and examines the relationship between hypertension and weight of Taiwanese young adolescents. Two cross-sectional surveys, administered in 1996 and 2006, to junior-high school in Taipei were included. Anthropometric and blood pressure were measured using standard methods, and structured questionnaire was used to collect personal history and lifestyle characteristics. Overweight and obesity are defined based on Taiwan's Department of Health criteria and bases pre-hypertension and hypertension on the 90th and 95th percentile distribution of blood pressure of the population of both surveys. The prevalence of pre-hypertension in Taiwan between 1996 and 2006 increased from 12.0 to 14.4% for boys and decreased from 9.5 to 9.4% for girls. Hypertension increased from 22.8-29.7% and 12.5-20.7% for both boys and girls, respectively. In 1996, compared with normal young adolescents, the risk of hypertension for overweight was 1.8 times higher for boys and 3.4 times for girls. However, the risk of hypertension for overweight in 2006 was 1.7 times higher for boys and 1.5 times higher for girls compared with normal. Every unit increment of body mass index and waist circumference was associated with 17-27% and 6-11% risk of hypertension in both genders in 1996, and was associated with 9-13% and 4% risk of hypertension among young adolescents in 2006, respectively. The prevalence of hypertension has increased significantly in young adolescents, especially for overweight. It is necessary to enrol young adolescents in weight management programs to prevent hypertension-related co-morbidities.

Addressing childhood overweight and obesity in the dental office: rationale and practical guidelines

The prevalence of childhood obesity has increased dramatically in the past 3 decades. The purposes of this paper were to: review health and dental implications; present guidelines for tracking body mass index (BMI) percentiles in children; and discuss reasonable "next steps" to take in communicating with parents and other health professionals. The health implications of childhood obesity warrant early monitoring, diagnosis, and treatment. Trends in visitation patterns of children offer dentists an unusual opportunity and an important role in addressing childhood obesity through regular monitoring of height, weight, and BMI percentiles. Dentists' collaborations with pediatricians, registered dietitians, and parents have the potential to address the detrimental physical and psychosocial effects of childhood obesity. We encourage dentists to determine height, weight, and BMI percentiles for their patients at least annually. They should refer patients with unhealthy weight trajectories to pediatricians or family physicians and consider ancillary referrals to registered dietitians.

Evidence of shared genetic effects between pre- and postobesity epidemic BMI levels

United States has experienced a widespread obesity epidemic. However, it is unclear whether the obesogenic environment has uncovered genes previously unimportant in adiposity or whether genes influencing obesity are the same before and after the obesity epidemic. The objective of this study was to test whether BMI pre- and postobesity epidemic would be controlled by shared genetic effects. A 25-30-year follow-up of parents and children who participated in the National Institutes of Health-National Heart, Lung, and Blood Institute Lipid Research Clinics (LRC) Princeton School Study, 1973-1976, were followed up in 1999-2004 in the Princeton Follow-up Study (PFS). Heritability of BMI and genetic correlations between pre-epidemic BMI and BMI z-scores in adolescents and postobesity epidemic BMI were calculated. Even though they had similar ages, offspring had higher BMI in PFS than their parents in LRC (28.5 +/- 6.6 vs. 26.1 +/- 4.4, P < 0.0001). BMI measurements in offspring were strongly heritable (BMI(LRC): h(2) = 0.78 +/- 0.17; BMI z-score(LRC): h(2) = 0.61 +/- 0.16; BMI(PFS): h(2) = 0.64 +/- 0.16, all P < or = 0.0001). Further, the change of BMI exhibited a high heritability (h(2) = 0.51 +/- 0.18, P = 0.003). Bivariate analysis of BMI in LRC and PFS showed significant genetic correlation (0.70 +/- 0.16, P = 0.005), whereas the environmental correlation was not significant (0.36 +/- 0.17). Although the obesogenic environment may have changed between the 1970s and 2000s, many of the same genes are likely to be involved in establishing genetic susceptibility to obesity. Furthermore, shared genetic effects survive the period of the transition from adolescence to adulthood.

Preteen insulin levels interact with caloric intake to predict increases in obesity at ages 18 to 19 years: a 10-year prospective study of black and white girls

We evaluated the associations of teenage insulin and adolescent diet with 10-year weight gain in an analysis sample of black and white girls matched for pubertal stage, body mass index (BMI) (or fat mass), and insulin at ages 9 to 10 years. We hypothesized that preteen insulin and insulin resistance would interact with dietary factors to positively predict increases in BMI. Furthermore, we hypothesized that increased insulin and insulin resistance, interacting with higher caloric intake during adolescence, would lead to greater increments in BMI in black girls than in white girls. Prospective 10-year follow-up was performed on 215 pairs of black and white schoolgirls matched at baseline by BMI (or fat mass), insulin, and pubertal stage, with repeated measures of body habitus, insulin, and dietary intake. When matched for BMI, black girls had higher fat-free mass and white girls had higher fat mass at ages 9 to 10 years. Black-white differences in caloric intake were not significant at ages 9 to 10 years, but black girls consumed more calories at age 19 years. Black girls consumed a greater percentage of calories from fat throughout. At age 19 years, black girls had higher BMI, fat mass index, and insulin. When matched at ages 9 to 10 years for fat mass, black girls were heavier, had higher BMI, and had greater fat-free mass. By ages 18 to 19 years, black girls continued to have higher BMI, but had accrued higher fat mass and a higher percentage of body fat. By stepwise multiple regression, 10-year increases in BMI were predicted by ages 9 to 10 years BMI, 10-year change in insulin, and a 3-way interaction between ages 9 to 10 years insulin, adolescent caloric intake, and race (higher in black girls) (all Ps < .0001). Insulin at ages 9 to 10 years interacts with caloric intake to increase BMI by age 19 years. There appear to be intrinsic black-white metabolic differences that lead to greater gains in fat during adolescence in black girls. Evaluating BMI and insulin at ages 9 to 10 years could identify girls (particularly black) who would optimally benefit from dietary and exercise interventions to avoid obesity.

Gestational diabetes: the forerunner for the development of maternal and childhood obesity and metabolic syndrome?

OBJECTIVE

To examine the risk of obesity and metabolic syndrome in women with a history of gestational diabetes mellitus and in offspring born to mothers with gestational diabetes mellitus.

METHODS

A review of studies examining the development of obesity, hypertension, metabolic abnormalities, metabolic syndrome, and type II diabetes in mothers with a history of gestational diabetes mellitus and control mothers, and offspring of mothers with a history of gestational diabetes and control mothers.

RESULTS

Longitudinal studies demonstrate that women with a prior history of gestational diabetes mellitus and obesity are at significantly greater risk of developing metabolic syndrome than mothers with no history of gestational diabetes or obesity. The development of metabolic syndrome in children with increasing age is related to maternal gestational diabetes mellitus, maternal glycemia in the 3rd trimester, maternal obesity, neonatal macrosomia, and childhood obesity.

CONCLUSIONS

The current prevalence of obesity in both adults and children and associated disorders of blood pressure and lipid metabolism, suggest a perpetuating cycle of increasing obesity, insulin resistance, and abnormal lipid metabolism, which has ominous consequences for future generations.

Stability of adolescent body mass index during three years of follow-up

OBJECTIVE

A 4-year longitudinal study was conducted to determine the prevalence of overweight, detect shifts in body mass index (BMI) distribution, and determine which adolescents were at risk for pathologic weight gain.

STUDY DESIGN

BMI was analyzed in 1746 adolescents in years 1 (2001-2002) through 4 (2004-2005) of a school-based study. Changes in BMI-Z according to baseline BMI category were examined with general linear modeling.

RESULTS

In year 1, the prevalence of at risk for overweight (BMI = 85th-95th percentile) and overweight (BMI > or = 95th percentile) was 19.1% and 18.1%, respectively. Between years 1 and 4, the cohort exhibited no increase in the prevalence of at risk for overweight (19.1% versus 17.2%) or overweight (18.2% versus 18.8%; P > .5). The mean BMI Z-score (BMI-Z) for the cohort was identical in years 1 and 4 (0.66 +/- 1.0 Z-score units). Although the overall cohort exhibited stability in BMI-Z, individuals at the lowest categories of BMI-Z (year 1 BMI Z-score < 0) exhibited significant increases in BMI Z-score by year 4 (P < .01), with lean girls gaining more than lean boys (P for difference < .007).

CONCLUSION

The study cohort exhibited stability in adiposity during 3 years of follow-up. However, lean adolescents, particularly girls, experienced significant increases in BMI-Z, beyond that expected for age- and sex-related growth.

Instability in the diagnosis of metabolic syndrome in adolescents

BACKGROUND

Factor analyses suggest that the structure underlying metabolic syndrome is similar in adolescents and adults. However, adolescence is a period of intense physiological change, and therefore stability of the underlying metabolic structure and clinical categorization based on metabolic risk is uncertain.

METHODS AND RESULTS

We analyzed data from 1098 participants in the Princeton School District Study, a school-based study begun in 2001-2002, who were followed up for 3 years. We performed factor analyses of 8 metabolic risks at baseline and follow-up to assess stability of factor patterns and clinical categorization of metabolic syndrome. Metabolic syndrome was defined using the current American Heart Association/National Heart, Lung, and Blood Institute definition for adults (AHA), a modified AHA definition used in prior pediatric metabolic syndrome studies (pediatric AHA), and the International Diabetes Federation (IDF) guidelines. We found that factor structures were essentially identical at both time points. However, clinical categorization was not stable. Approximately half of adolescents with baseline metabolic syndrome lost the diagnosis at follow-up regardless of the definitions used: pediatric AHA=56% (95% confidence interval [CI], 42% to 69%), AHA=49% (95% CI, 32% to 66%), IDF=53% (95% CI, 38% to 68%). In addition to loss of the diagnosis, new cases were identified. Cumulative incidence rates were as follows: pediatric AHA=3.8% (95% CI, 2.8% to 5.2%); AHA=4.4% (95% CI, 3.3% to 5.9%); IDF=5.2% (95% CI, 4.0% to 6.8%).

CONCLUSIONS

During adolescence, metabolic risk factor clustering is consistent. However, marked instability exists in the categorical diagnosis of metabolic syndrome. This instability, which includes both gain and loss of the diagnosis, suggests that the syndrome has reduced clinical utility in adolescence and that metabolic syndrome-specific pharmacotherapy for youth may be premature.

Has blood pressure increased in children in response to the obesity epidemic?

The associations between elevated blood pressure and overweight, on one hand, and the increasing prevalence over time of pediatric overweight, on the other hand, suggest that the prevalence of elevated blood pressure could have increased in children over the last few decades. In this article we review the epidemiologic evidence available on the prevalence of elevated blood pressure in children and trends over time. On the basis of the few large population-based surveys available, the prevalence of elevated blood pressure is fairly high in several populations, whereas there is little direct evidence that blood pressure has increased during the past few decades despite the concomitant epidemic of pediatric overweight. However, a definite conclusion cannot be drawn yet because of the paucity of epidemiologic studies that have assessed blood pressure trends in the same populations and the lack of standardized methods used for the measurement of blood pressure and the definition of elevated blood pressure in children. Additional studies should examine if favorable secular trends in other determinants of blood pressure (eg, dietary factors, birth weight, etc) may have attenuated the apparently limited impact of the epidemic of overweight on blood pressure in children.

Increasing body mass index z-score is continuously associated with complications of overweight in children, even in the healthy weight range

CONTEXT

Overweight/obesity in children is increasing. Incidence data for medical complications use arbitrary cutoff values for categories of overweight and obesity. Continuous relationships are seldom reported.

OBJECTIVES

The objective of this study is to report relationships of child body mass index (BMI) z-score as a continuous variable with the medical complications of overweight.

DESIGN

This study is a part of the larger, prospective cohort Growth and Development Study.

SETTING

Children were recruited from the community through randomly selected primary schools. Overweight children seeking treatment were recruited through tertiary centers.

PARTICIPANTS

Children aged 6-13 yr were community-recruited normal weight (n = 73), community-recruited overweight (n = 53), and overweight treatment-seeking (n = 51). Medical history, family history, and symptoms of complications of overweight were collected by interview, and physical examination was performed. Investigations included oral glucose tolerance tests, fasting lipids, and liver function tests.

MAIN OUTCOME MEASURE

Adjusted regression was used to model each complication of obesity with age- and sex-specific child BMI z-scores entered as a continuous dependent variable.

RESULTS

Adjusted logistic regression showed the proportion of children with musculoskeletal pain, obstructive sleep apnea symptoms, headaches, depression, anxiety, bullying, and acanthosis nigricans increased with child BMI z-score. Adjusted linear regression showed BMI z-score was significantly related to systolic and diastolic blood pressure, insulin during oral glucose tolerance test, total cholesterol, high-density lipoprotein, triglycerides, and alanine aminotransferase.

CONCLUSION

Child's BMI z-score is independently related to complications of overweight and obesity in a linear or curvilinear fashion. Children's risks of most complications increase across the entire range of BMI values and are not defined by thresholds.

Emergence of sex differences in prevalence of high systolic blood pressure: analysis of a longitudinal adolescent cohort

BACKGROUND

High systolic blood pressure (SBP) occurs more frequently both among men and boys than among women and girls. No longitudinal study has investigated whether the impact of SBP determinants differ according to sex in youth.

METHODS AND RESULTS

Between 1999 and 2005, an adolescent cohort (n=1267) completed a questionnaire survey and underwent biannual blood pressure and anthropometric assessment (grades 7, 9, and 11). Boys accounted for approximately 50% of those with high SBP at grade 7 and 9 assessments but 67% of those with high SBP at the grade 11 assessment. As computed through a generalized estimating equations logistic regression model (sex, age, sex and age interaction term, overweight, physical activity, sedentary behavior, heart rate, household income, tobacco use, and 4 language categories), the likelihood of high SBP values among boys compared with girls was 1.29 (95% CI, 0.77 to 2.16) in grade 7, 1.98 (95% CI, 1.35 to 2.93) in grade 9, and 2.74 (95% CI, 1.52 to 4.94) in grade 11. Although there was a significant interaction between sex and age, interaction terms of sex with overweight, sedentary behavior, and physical activity were not statistically significant. Overweight (odds ratio [OR], 2.63; 95% CI, 1.76 to 3.92) and sedentary behavior (OR, 1.17 for increment of 5 hours weekly; 95% CI 1.04 to 1.33) demonstrated positive associations with high SBP values. Physical activity was inversely associated with the presence of high SBP (OR, 0.92 for increment of 5 activities in 7 days; 95% CI, 0.84 to 1.00).

CONCLUSIONS

Boys are more likely than girls to develop high SBP as they approach adulthood. Even among overweight adolescents, reducing sedentary behavior and increasing physical activity may lower the risk of high SBP.

Age-dependent changes in body size of Greek boys from 1982 to 2002

OBJECTIVE

The prevalence of childhood obesity has been rising during the past decades in many parts of the world, including Greece. The dispersion of these trends across age, however, is less clear. The aim of this study was to examine the relationship between age and 20-year changes in anthropometric characteristics of Greek boys.

RESEARCH METHODS AND PROCEDURES

A total of 204 and 106 boys 9 years old, 163 and 274 boys 12 years old, and 161 and 240 boys 15 years old were randomly recruited in 1982 and 2002, respectively, throughout the county of Iraklio, Crete, Greece. Height, weight, and BMI were measured.

RESULTS

Contemporary 9 and 12 year olds were taller than their peers in 1982 (+2.9% and +1.2%, respectively; p < 0.005), but this was not the case for 15 year olds (-0.8%; p = 0.083). Body weight and BMI were higher now than in the 1980s, and this held true for all age groups (p < 0.001). Increases in weight also showed a decline with advancing age (+17.4%, +13.9%, and +4.0% for 9, 12, and 15 year olds, respectively), whereas BMI changes were similar for those 9 and 12 years of age (approximately 10.5%), but were almost 2-fold higher than in 15 year olds (+5.5%).

DISCUSSION

Contemporary boys are taller, heavier, and have higher BMI values than their peers in 1982, but the magnitude of these increases gradually declines with advancing age. Rates of increase in BMI, however, seem to have greatly accelerated compared with previous decades.

Changing relationships of obesity and dyslipidemia in Greek children: 1982-2002

BACKGROUND

The prevalence of childhood overweight and obesity has been increasing rapidly during the past decades in many parts of the world. Less is known with respect to the effects of increasing adiposity on blood lipid profile. The present study was designed to examine the influence of adiposity on secular trends in anthropometric characteristics and plasma lipids of Greek children.

METHODS

A total of 419 and 374 boys with normal body weight and 109 and 246 boys with abnormal body weight (overweight and obese) were randomly recruited in 1982 and 2002, respectively (aged 12.1 +/- 0.1 years). Height, weight, body mass index (BMI, kg/m(2)), Rohrer index (kg/m(3)), plasma total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglyceride (TG), TC/HDL-C ratio, and LDL-C/HDL-C ratio were determined.

RESULTS

Temporal changes in weight (positive), BMI (positive), HDL-C (negative), and cholesterol ratios (positive) were greater among overweight and obese vs. normal-weight boys (P < 0.05), while those for height (positive), LDL-C (positive), TG (positive), and TC (no change) were of similar magnitude. The increase in Rohrer index since 1982 failed to reach significance for children with normal body weight (P = 0.077) but did so for overweight and obese subjects (P = 0.027).

CONCLUSIONS

These results indicate that secular increases in measures of fatness and adverse changes in plasma lipids were more pronounced among overweight and obese children than among normal-weight individuals, although qualitatively similar shifts were observed across the entire population.

Trajectory of systolic blood pressure in children and adolescents

PURPOSE

Rapid height and weight changes during childhood contribute markedly to blood-pressure change during children's physical growth. This article evaluates the differences in systolic blood pressure (SBP) growth or changes between four gender-ethnic groups: African American males (AM), Caucasian males (CM), African American females (AF), and Caucasian females (CF).

METHODS

Subjects 6-9 years old at entry (n = 1302) were followed for 12 years. The repeated-measure data of SBP were analyzed using the Gompertz growth model with random coefficients.

RESULTS

Mean SBP (mmHg) at age 6 years was lowest in African American girls (82.23 +/- 0.76) and highest in Caucasian boys (102.83 +/- 0.5). And for both ethnic groups, girls had lower levels at which SBP growth stopped. The peak growth ages (years) also differed by group: 9.30 +/- 0.73, 9.91 +/- 0.28, 10.00 +/- 0.82, and 10.60 +/- 0.22 for African American girls, African American boys, Caucasian girls and Caucasian boys, respectively.

CONCLUSION

SBP growth differed among gender-ethnic groups with respect to mean SBP level at age 6, the level at which SBP growth stops and the mean age at which SBP growth rate was at its peak.

Twenty-year dynamics in adiposity and blood lipids of Greek children: regional differences in Crete persist

AIM

To examine whether secular trends in adiposity and blood lipid profile of Greek children manifested equally among individuals from urban and rural provinces.

METHODS

Cretan boys (aged 12.1+/-2.3 y) from urban and rural areas of Crete were recruited in 1982 (n=277 and 251, respectively) and 2002 (n=440 and 180, respectively). Height, weight, and body mass index (BMI), as well as plasma lipid concentrations were measured and compared across cohorts (1982 vs 2002) and regions (urban vs rural) by two-way analysis of covariance (adjusted for age) with interaction.

RESULTS

Temporal changes in height (positive), weight (positive), and BMI (positive) manifested equally in children from urban and rural provinces, as no interaction was detected. Similar results were obtained for triacylglycerol (positive), low-density lipoprotein cholesterol (LDL-C, positive) and high-density lipoprotein cholesterol (negative) concentrations. A significant interaction was observed only for total cholesterol (TC), which increased from 1982 among rural (by 6.2%, p < 0.05) but not among urban boys. In all other instances, regional differences in 1982 persisted in 2002. More specifically, children from urban provinces were taller, heavier, and had higher BMI values than those from rural areas, while they also had higher LDL-C concentrations, whether nowadays or 20 y ago. Regional differences in TC in 1982 were not apparent in 2002.

CONCLUSION

These findings suggest that changes in anthropometric characteristics and plasma lipids during the past 20 y have occurred largely in parallel among urban and rural Cretan children, and they emphasize the importance of developing a common national strategy for the prevention and treatment of childhood obesity in Greece.

Regulation of body mass and management of childhood overweight

Obesity has become an increasingly important public health problem. Recent evidence suggests that obesity has become a close second to tobacco use as a preventable cause of death in the United States. During the past decade an increase in the prevalence of type 2 diabetes in adolescents has been observed. The association of type 2 diabetes and obesity is well established and most adolescents with type 2 diabetes have body mass index (BMI) in a range that would already be considered obese in an adult. Childhood overweight is also associated with the atherosclerotic process. In the Bogalusa autopsy study, Berenson et al. found that the extent of fatty streaks and fibrous plaques in the aorta and coronary arteries was associated with BMI. There are three modalities currently available for the treatment of overweight in children and adolescents, including behavioral approaches, pharmacologic approaches, and surgical approaches. Surgical intervention may be considered if the BMI > or = 40 kg/m2 and a severe medical comorbidity including type 2 diabetes, obstructive sleep apnea or pseudotumor cerebri, or if the BMI is > or = 50 kg/m2 and comorbid conditions such as hypertension, dyslipidemia, or the metabolic syndrome are present. Behavioral intervention is usually made by a psychologist, behavioral therapist, dietician, or exercise physiologist. There is evidence that the effect of behavioral therapy for weight loss in childhood will be longer lasting than that seen in adults.

Secular trends in cardiovascular risk factors among school-aged boys from Crete, Greece, 1982-2002

OBJECTIVE

The aim of the present study was to examine secular trends in major cardiovascular disease (CVD) risk factors, that is, obesity and dyslipidaemia, among Cretan children during 1982-2002.

DESIGN

Epidemiological survey.

SETTING AND SUBJECTS

A total of 528 boys in 1982 and 620 boys in 2002, aged 12.1+/-0.1 y, were randomly selected from urban and rural regions throughout the county of Iraklio, Crete, Greece. Care was taken so that all procedures in 2002 closely matched those in 1982.

RESULTS

Mean height, weight, and body mass index (BMI) were 1.1, 9.6, and 8.4% higher, respectively, in 2002 vs 1982 (P<0.001). The prevalence of overweight and obesity has risen by 63 and 202%, respectively (P<0.001). Contemporary children were found to have 3.6% higher total cholesterol (TC), 24.9% lower high-density lipoprotein-cholesterol (HDL-C), 25.3% higher low-density lipoprotein-cholesterol (LDL-C), 19.4% higher triacylglycerol, 36.6% higher TC/HDL-C ratio, and 60.3% higher LDL-C/HDL-C ratio compared with their peers in 1982 (P<0.003). These differences persisted even when adjusting for BMI (P<0.02). The proportion of children having abnormal lipid values was much greater nowadays than in the 1980s, yielding odds ratios of 1.4-8.8 (P<0.005).

CONCLUSIONS

Results are indicative of a largely deteriorated CVD risk profile in Cretan children since 1982, and predict an unfavourable CVD morbidity and mortality for this population in the foreseeable future.

[Evaluation of insulin resistance and lipid profile in turner syndrome]

OBJECTIVE

To evaluate the presence of insulin resistance (IR) and changes in lipid profile in Turner Syndrome (TS), and to check the influence of age, karyotype, systemic arterial hypertension (SAH), height, weight, body mass index (BMI), and pubertal development.

PATIENTS AND METHODS

A transversal study of 35 TS patients, confirmed with karyotype (5 to 43 years), without previous use of anabolic steroid or hGH, with evaluation of blood pressure, pubertal development, anthropometric data, measurement of waist (W), hip (H), W to H ratio, total cholesterol, HDL, triglycerides (TGC), LDL, insulin and glucose. HOMA and QUICKI indexes were calculated, as well as glucose to insulin ratio (G/I). Data were examined by the Mann-Whitney and Spearman tests.

RESULTS

Ten patients were >20 years. Seventeen had a 45,X karyotype and 6 structural aberrations; differences of the variables in relation to the karyotypes were not observed; 15 were nonpubertal and 20 pubertal; TGC and HOMA were significantly higher in puberty, while G/I was lower. Seven had normal height, 8 had BMI >25 Kg/m2 (6 between 25 and 30, and 2 >30), and 19 W/H >0.85. Cholesterol levels were 180 +/- 42mg% (4 >240); HDL 57 +/- 16mg%; LDL 99 +/- 34 mg%; TGC 108 +/- 96 mg% (2 >200); HOMA 1.01 +/- 0.71; QUICKI 0.4 +/- 0.04 and G/I 23.5 +/- 12.1 (2 <7.0).

CONCLUSIONS

Changes were observed in lipid profile independent of age, karyotype, SAH and obesity, but associated with IR. The frequency of IR was lower than described in literature, and seems to be directly linked to chronological age, obesity and estrogen therapy.

Social inequalities in biomarkers of cardiovascular risk in adolescence

OBJECTIVE

Cardiovascular disease, which begins early in life but often is not manifest until adulthood, is the nation's leading cause of mortality. Social inequalities in cardiovascular disease are pervasive, yet the process by which they accrue is poorly understood. The objective of this study was to explore the associations between socioeconomic status, a range of biomarkers reflective of cardiovascular risks, and a cumulative physiological risk score among adolescents.

METHODS

Non-Hispanic black and white high school students (N = 758) in a suburban Midwestern public school district had a physical examination to measure height, weight, and waist circumference and a fasting morning blood sample drawn to assess cortisol, insulin, glucose, glycosylated hemoglobin, fibrinogen, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, and triglycerides. A cumulative risk score was created from these physiological measures and waist circumference. Information on parent education and household income was obtained from a parent in a separate survey. Generalized estimating equation models were used to assess the association of parent education to the risks and the cumulative risk score adjusting for age, gender, and race.

RESULTS

Lower parent education was associated with higher insulin, higher glucose, greater insulin resistance, higher LDL cholesterol, lower HDL cholesterol, higher waist circumference, and higher body mass index (p <.05 for all), but not cortisol, fibrinogen, glycosylated hemoglobin, or triglycerides in adjusted analyses. Cumulative risk scores ranged from 0 to 7 and were highly skewed; the median risk score was 1. A total of 7.4% had risk scores of 4 or more. Lower parent education was also associated with higher cumulative risk score (p <.001) and this association was maintained after adjustment for body mass index. Risk scores were highest, on average, among those with insulin levels greater than 1 standard deviation above the mean (mean risk score = 3.2, standard error = 0.18, median = 3).

CONCLUSION

Lower parent education is associated with multiple metabolic risks and cumulative risk in adolescents, suggesting that there is a strong intergenerational transfer of education's influence on cardiovascular health. Our data imply that regulation of insulin may be a key factor underlying the influence of lower parent education on cardiovascular health early in the life course.

Trends in risk factors for cardiovascular disease among children and adolescents in the United States

BACKGROUND

The increasing prevalence of obesity among children and adolescents in recent decades might have affected trends in obesity-associated risk factors for cardiovascular disease.

PARTICIPANTS AND METHODS

We used data for 12,665 children and adolescents, 2 to 17 years of age, from the Third National Health and Nutrition Examination Survey (1988-1994) and for 3611 children and adolescents from National Health and Nutrition Examination Survey 1999-2000.

RESULTS

For participants 2 to 17 years of age, waist circumference increased 1.6 cm among male subjects and 2.4 cm among female subjects. Mean systolic blood pressure increased by 2.2 mm Hg among children and adolescents 8 to 17 years of age. There were significant decreases in concentrations of triglycerides (8.8 mg/dL) and glucose (2.5 mg/dL) among children and adolescents 12 to 17 years of age. Mean concentrations of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and glycosylated hemoglobin were relatively unchanged. Some changes in means of risk factors varied according to age.

CONCLUSIONS

The temporal trends for risk factors among children and adolescents during the 1990s exhibited different patterns. The effects of the increasing prevalence of obesity on the cardiovascular health of children and adolescents remain unclear.

Contrasting prevalence of and demographic disparities in the World Health Organization and National Cholesterol Education Program Adult Treatment Panel III definitions of metabolic syndrome among adolescents

OBJECTIVE

To determine prevalence of metabolic syndrome (MS) among adolescents by using definitions from the National Cholesterol Education Program Adult Treatment Panel III (NCEP) and World Health Organization (WHO) guidelines and to compare the populations identified by these definitions.

STUDY DESIGN

School-based, cross-sectional study of 1513 black, white, and Hispanic teens who had a fasting morning blood sample drawn and a physical examination.

RESULTS

Overall, the prevalence of NCEP-defined MS was 4.2% and of WHO-defined MS was 8.4%. MS was found almost exclusively among obese teens, for whom prevalence of NCEP-defined MS was 19.5% and prevalence of WHO-defined MS was 38.9%. Agreement between definitions was poor (kappa statistic=0.41). No race or sex differences were present for NCEP-defined MS. However, nonwhite teens were more likely to have MS by WHO criteria (RR, 1.40; 95% CI, 1.04, 1.87), and MS was more common among girls if the WHO-based definition was used (RR, 1.26; 95% CI, 1.08, 1.88).

CONCLUSIONS

Among adolescents, obesity is a powerful risk for MS. Important demographic and clinical differences exist in the typology of MS, depending on the definition. Such discrepancies suggest that the concept of a common pathologic syndrome or etiologic mechanism underlying MS as defined by these guidelines may be flawed.

Measuring the prevalence of overweight in Texas schoolchildren

OBJECTIVES

We describe results from year 1 of a surveillance system to monitor body mass index in children at the state level.

METHODS

A sample of 6630 children attending Texas public schools, weighted to represent 4th, 8th, and 11th grades within race/ethnic subpopulations, was assessed. Body mass index was calculated from measured height and weight; demographic information was obtained from a questionnaire.

RESULTS

Prevalence of overweight was 22.4%, 19.2%, and 15.5% for 4th-, 8th-, and 11th-grade students, respectively. Overweight prevalence was highest among Hispanic boys (29.5%-32.6%), fourth-grade Hispanic girls (26.7%), and fourth- and eighth-grade African American girls (30.8% and 23.1%, respectively). Eleventh-grade White/other girls had the lowest prevalence of overweight (5.5%).

CONCLUSIONS

These data confirm the increasing prevalence of overweight among US children, especially among Hispanic and African American students compared to White/other students and fourth-grade students relative to 8th- and 11th-grade students.

Resting energy expenditure in obese children aged 4 to 15 years: measured versus predicted data

AIM

To measure the relationship of resting energy expenditure (REE) and body composition, and to compare REE data calculated from anthropometric parameters using published equations with measurements obtained by indirect calorimetry (IC) in a population of obese paediatric patients.

METHODS

The study included 82 healthy obese paediatric subjects (49 boys, 33 girls; body mass index 29.6 +/- 5.0 kg/m , age 1 1.4 +/- 2.6 y, weight 72.4 +/- 20.9 kg, height 155 +/- 14 cm). REE was measured by IC, body composition was determined by dual energy X-ray absorptiometry (DXA). Bootstrap analysis was performed to validate the step-down linear regression analysis results.

RESULTS

Lean body mass (LBM) and weight were identified as the most significant determinants of REE. LBM was the best single predictor (r = 0.78; p < 0.001) for REE. Regression equations are given in the text. Prediction of REE on the basis of published anthropometric formulas was strongly dependent from the equation used. Some equations tend to underestimate REE in the population studied with a considerable systematic error.

CONCLUSION

In the present paper we show that (1) the published equations to predict REE in obese subjects yield scattered data and some are even biased by a systematic error, and that (2) the inclusion of DXA-derived LBM improves accuracy and precision of predicted REE in boys and girls aged from 4 to 10 y and in boys from 11 to 15 y.

Secular trends in variables associated with the metabolic syndrome of North American children and adolescents: A review and synthesis

The aim of this article is to summarize and critique reports from selected large-scale population health surveys (U.S. and Canada national health surveys (e.g., National Health and Nutrition Examination Survey, Youth Risk Behavior Survey, and Canada Fitness Survey), and active research programs in preventive pediatric cardiology (i.e., Bogalusa Heart Study, Princeton Lipids Study, and Minneapolis Blood Pressure Study)) pertaining to the secular trend in variables associated with the metabolic syndrome of North American youth. These surveys were chosen since they have published peer-reviewed articles on the topic and consist of relatively large samples. The increased body mass index and prevalence of overweight and obesity are clear, particularly over the past two decades. The secular increase in overweight and obesity cannot be linked to available self-report data on physical activity or diet, although measurement issues need to be considered. The emergence of Type II diabetes in adolescents parallels the increase in obesity; however, subsequent changes in blood lipids and blood pressure are less clear. There is some evidence to suggest adverse changes in the blood lipid profile. Aerobic fitness, as determined by maximal oxygen consumption (VO(2max)), has not appeared to change in youth except perhaps for adolescent females. The results suggesting the emergence of metabolic syndrome X during childhood and adolescence are discussed in the context of perturbation and dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. It can be suggested that a subsistent lifestyle consisting of increased lifestyle activity (not exercise per se), a prudent diet, adequate sleep and rest, and stress reduction be advocated to combat diseases of Western Civilization/metabolic syndrome that have affected North American children (and adults) in recent years. The results also highlight the importance of population surveillance of obesity, physical activity, and dietary intake and cardiovascular health of children into the 21st century.

Platelet aggregation, blood viscosity and serum lipids in hypertensive and obese children

A group of 35 patients (median age 15.5 years, range 8-17 years) with juvenile essential hypertension, 15 with body mass index (BMI kg/m(2)) <25 and 20 with BMI >25, as well as 35 age and sex matched controls (BMI <25 n=20; BMI >25 n=15) were investigated to study the role of hypertension and obesity, separately and in combination, on in vitro platelet aggregation, blood and plasma viscosity, plasma lipid concentrations and lipid peroxidation as well as nitric oxide (NO) production. Obese children (hypertensive and controls) had significantly higher concentrations of total cholesterol and triglycerides. The levels of high density lipoprotein (HDL)-cholesterol were lower in obese hypertensive children than their non-obese counterparts. There was a significant increase in platelet aggregation and a decrease in NO levels in hypertensive patients (obese and non-obese) reflecting a significant negative correlation (r=-0.553 and -0.530, n=35; P<0.01, respectively). However, an increased tendency to aggregation was also evident in obese normotensive patients. A significant positive correlation was observed between the platelet aggregation and BMI (r=0.501, n=35; P<0.01). Plasma free thiols were decreased in hypertensive children independent of their BMI. An increased lipid peroxidation and higher blood and plasma viscosity were found only in obese patients with hypertension. Multivariate analysis revealed significant interactions in the effects of obesity and hypertension on platelet aggregation and thiol oxidation.

CONCLUSION

in obese children an increased platelet aggregation and oxidative insult contribute to the development of hypertension and to the promotion of vascular damage.

[Hypercholesterolemia and its risk factors among schoolchildren]

OBJECTIVE

To identify the risk factors of hypercholesterolemia among schoolchildren aged 7 to 10 years, Brazil.

METHODS

A case-control study was conducted among 172 children matched by sex and age +/-3 months in Campinas, Brazil. Cases were defined as hypercholesterolemia when cholesterol (3)200 mg/dL and controls when cholesterol 140 and 170 mg/dL. Besides drawing a blood sample for cholesterol, blood pressure, body mass index and family history of cardiovascular diseases were documented. Data were analyzed through bivariate correlation using t-test for quantitative variables and Chi-square for family history of cardiovascular diseases. Odds ratio was used to estimate the risk of hypercholesterolemia.

RESULTS

On average, a cholesterol of 215 mg/dL for cases and 154 mg/dL for controls was found. The mean systolic blood pressure was 107 mmHg for cases and 106 mmHg for controls. The mean of diastolic blood pressure was 67 mmHg for cases and 68 mmHg for controls. The mean body mass index was 18.2 kg/m(2) in the case-group and 17.1 kg/m(2) in the control group. Bivariate analysis showed an association between hypercholesterolemia and body mass index (p=0.048). The odds ratio revealed obesity as a risk factor in this study population (OR=2.17; CI=1.05 to 4.45).

CONCLUSIONS

The results showed obesity as a risk factor for hypercholesterolemia.

Oxidative stress in juvenile essential hypertension

OBJECTIVE

Oxidative stress, an antioxidant/pro-oxidant imbalance, in patients with juvenile essential hypertension was measured via several biochemical parameters. As the blood pressure is associated with the body mass index (BMI), results were compared with those on BMI-matched controls.

DESIGN AND SETTING

A prospective observational study at a university teaching hospital.

PATIENTS

Children and adolescents with essential hypertension (mean standard deviation: age 14.4 +/- 3.1 years, BMI 25.0 +/- 6.9 kg/m(2), n = 52) before any treatment, and controls with a similar BMI distribution (age 14.3 +/- 4.3 years, BMI 24.4 +/- 6.6 kg/m(2), n = 48).

METHODS

Measurements were made of the plasma levels of (1) nitrites + nitrates, an indirect measure of available nitric oxide; (2) lipid peroxidation end-products, as malondialdehydes and free thiols; and (3) the redox status of the red blood cell glutathione, as a new oxidative stress parameter.

RESULTS

There were decreased plasma levels of nitrates and increased levels of lipid peroxidation end-products in the hypertensive patients, resulting in a consistent increase in the plasma lipid peroxidation/nitric oxide ratio as compared with the controls with the same BMI (P <0.01). This ratio additionally correlated directly with both the systolic and diastolic blood pressures for the overall patient population (P <0.001). A significant glutathione depletion in the red blood cells resulted in an elevated ratio of oxidized/reduced forms with a reduced antioxidant protective capacity in the hypertensive patients versus the BMI-matched controls (P <0.001).

CONCLUSIONS

The presence of systemic oxidative stress was proven in hypertensive children and adolescents, irrespective of their BMI.

Obesity and cardiovascular disease

Obesity is a major contributor to the prevalence of cardiovascular disease in the developed world, and yet has only recently been afforded the same level of attention as other risk factors of coronary artery disease. Obesity is a chronic metabolic disorder associated with cardiovascular disease and increased morbidity and mortality. It is apparent that a variety of adaptations/alterations in cardiac structure and function occur as excessive adipose tissue accumulates, even in the absence of comorbidities. Shifts toward a less physically demanding lifestyle are observed today throughout different populations, and this scourge associated with obesity implicates a corresponding increase in the number of individuals afflicted with the metabolic syndrome, which defines the obese patient as being "at risk." Adipose tissue is not simply a passive storehouse for fat, but an endocrine organ that is capable of synthesizing and releasing into the bloodstream a variety of molecules that may impact unfavorably the risk factor profile of a patient. Indeed, obesity may affect atherosclerosis through unrecognized variables and risk factors for coronary artery disease such as dyslipidemia, hypertension, glucose intolerance, inflammatory markers, and the prothrombotic state. By favorably modifying lipids, decreasing blood pressure, and decreasing levels of glycemia, proinflammatory cytokines, and adhesion molecules, weight loss may prevent the progression of atherosclerosis or the occurrence of acute coronary syndrome events in the obese high-risk population.

Obesity hypertension in children: a problem of epidemic proportions

Obesity has become an increasingly important medical problem in children and adolescents. In national surveys from the 1960s to the 1990s, the prevalence of overweight in children grew from 5% to 11%. Outcomes related to childhood obesity include hypertension, type 2 diabetes mellitus, dyslipidemia, left ventricular hypertrophy, nonalcoholic steatohepatitis, obstructive sleep apnea, orthopedic problems, and psychosocial problems. Once considered rare, primary hypertension in children has become increasingly common in association with obesity and other risk factors, including a family history of hypertension and an ethnic predisposition to hypertensive disease. Obese children are at approximately a 3-fold higher risk for hypertension than nonobese children. In addition, the risk of hypertension in children increases across the entire range of body mass index (BMI) values and is not defined by a simple threshold effect. As in adults, a combination of factors including overactivity of the sympathetic nervous system (SNS), insulin resistance, and abnormalities in vascular structure and function may contribute to obesity-related hypertension in children. The benefits of weight loss for blood pressure reduction in children have been demonstrated in both observational and interventional studies. Obesity in childhood should be considered a chronic medical condition that is likely to require long-term management. Ultimately, prevention of obesity and its complications, including hypertension, is the goal.

Dyslipidemia in pediatric renal disease: epidemiology, pathophysiology, and management

Dyslipidemia increases the risk of cardiovascular events among individuals with renal disease, and there is a growing body of evidence that it hastens the progression of renal disease itself. Children with nephrotic syndrome or renal transplants have easily recognized hyperlipidemia. Among those with chronic renal insufficiency or end-stage renal disease, detection of dyslipidemia requires more careful analysis and knowledge of normal pediatric ranges. Disordered lipoprotein metabolism results from complex interactions among many factors, including the primary disease process, use of medications such as corticosteroids, the presence of malnutrition or obesity, and diet. The systematic treatment of dyslipidemia in children with chronic renal disease is controversial because conclusive data regarding the risks and benefits are lacking. Hepatic 3-methylglutaryl coenzyme A reductase inhibitors (statins), fibrates, plant stanols, bile acid-binding resins, and dietary manipulation are options for individualized treatment. Prospective investigations are required to guide clinical management.

Pharmacological treatment of obesity in paediatric patients

The prevalence and severity of obesity appear to be increasing in the paediatric population. This has resulted in an increasing trend in outcomes related to obesity, such as type 2 diabetes mellitus. The current clinical approach to management of obesity in paediatric patients is behavioural therapy directed at changing diet and physical activity. While there are no pharmacological agents currently approved for the treatment of paediatric obesity, there is hope that agents approved for use in adults will prove useful in adolescents and children. Therapeutic trials are currently under way to evaluate some agents, e.g. orlistat and sibutramine. Controlled clinical trials are necessary to evaluate drugs for weight management in children and adolescents. It should not be assumed that the risks and benefits associated with these drugs are the same for children as for adults. It is also possible that as the understanding of the science of obesity advances, new agents will be developed which will have appropriate benefits and risks for use in children.

Cardiovascular disease risk factors and atherosclerosis in children and adolescents

As more is learned about the natural history of the development of atherosclerosis, it is clear that the process that results in morbidity and mortality in adults has its origins in childhood and adolescence. It is also clear that the traditional risk factors, such as hypertension and dyslipidemia, are important in the early stages of the process. It appears that the prevalence and severity of obesity are increasing in children and adolescents in the United States. This trend is associated with increasing blood pressure and the occurrence of type 2 diabetes mellitus in young individuals. These trends may result in increased cardiovascular morbidity and mortality as these overweight pediatric patients become obese adults. Intervention and prevention strategies should be directed at the pediatric population as a whole, as well as at higher-risk individuals. For the latter, it will be necessary to identify those at highest risk. Both nonpharmacologic and pharmacologic approaches may be necessary for treatment of pediatric patients with hyperlipidemia and hypertension. Studies are needed that evaluate the longer-term impact of intervention on cardiovascular risk factors in young patients.

Adolescents' perceptions of social status: development and evaluation of a new indicator

OBJECTIVE

Eliminating health disparities, including those that are a result of socioeconomic status (SES), is one of the overarching goals of Healthy People 2010. This article reports on the development of a new, adolescent-specific measure of subjective social status (SSS) and on initial exploratory analyses of the relationship of SSS to adolescents' physical and psychological health.

METHODS

A cross-sectional study of 10 843 adolescents and a subsample of 166 paired adolescent/mother dyads who participated in the Growing Up Today Study was conducted. The newly developed MacArthur Scale of Subjective Social Status (10-point scale) was used to measure SSS. Paternal education was the measure of SES. Indicators of psychological and physical health included depressive symptoms and obesity, respectively. Linear regression analyses determined the association of SSS to depressive symptoms, and logistic regression determined the association of SSS to overweight and obesity, controlling for sociodemographic factors and SES.

RESULTS

Mean society ladder ranking, a subjective measure of SES, was 7.2 +/- 1.3. Mean community ladder ranking, a measure of perceived placement in the school community, was 7.6 +/- 1.7. Reliability of the instrument was excellent: the intraclass correlation coefficient was 0.73 for the society ladder and 0.79 for the community ladder. Adolescents had higher society ladder rankings than their mothers (micro(teen) = 7.2 +/- 1.3 vs micro(mom) = 6.8 +/- 1.2; P =.002). Older adolescents' perceptions of familial placement in society were more closely correlated with maternal subjective perceptions of placement than those of younger adolescents (Spearman's rho(teens <15 years) = 0.31 vs Spearman's rho(teens 15 years) = 0.45; P <.001 for both). SSS explained 9.9% of the variance in depressive symptoms and was independently associated with obesity (odds ratio(society) = 0.89, 95% confidence interval = 0.83, 0.95; odds ratio(community) = 0.91, 95% confidence interval = 0.87, 0.97). For both depressive symptoms and obesity, community ladder rankings were more strongly associated with health than were society ladder rankings in models that controlled for both domains of SSS.

CONCLUSIONS

This new instrument can reliably measure SSS among adolescents. Social stratification as reflected by SSS is associated with adolescents' health. The findings suggest that as adolescents mature, SSS may undergo a developmental shift. Determining how these changes in SSS relate to health and how SSS functions prospectively with regard to health outcomes requires additional research.