Growth and overweight of Navajo youth: secular changes from 1955 to 1997

Physical Growth and Body Adiposity Curves in Students of the Maule Region (Chile)

Objectives: Physical growth and body adiposity patterns provide relevant information to infer the nutritional and health status of students. Our objectives were (a) to compare the variables of body adiposity and physical growth of Chilean children and adolescents with data from the CDC-2012 and international studies, and (b) to develop regional reference curves to evaluate growth and body adiposity. Methods: 8,261 children and adolescents were studied. We evaluated the weight, height, and waist circumference (WC). The Body Mass Index (BMI) was calculated. Their physical growth and body adiposity were compared with the CDC-2012 references as well as with other international references. Percentile curves for weight, height, BMI, and WC were constructed with the LMS method. Results: The Chilean students showed reduced weight and height during adolescence when compared with the CDC-2012 reference. During early ages, the BMI for the Chilean sample was lower while at advanced ages, the WC values were greater in comparison to the CDC-2012 reference. Graphic comparisons with international studies indicated that Chilean students weighed more at all ages. However, height was slightly greater until age 14 for males and age 11 for females. Body adiposity (BMI and WC) for the Chilean students was slightly higher at early ages while at later ages, adiposity values were relatively similar for both sexes. Conclusions: Discrepancies were observed between the physical growth and body adiposity trajectories and the American CDC-2012 references and the international studies. The proposed percentiles for weight, height, BMI, and WC for each age and sex may be useful for health sciences professionals and researchers.

Secular changes in physical growth and obesity among southwestern American Indian children over four decades

BACKGROUND AND OBJECTIVES

Most studies describing childhood obesity in the United States are based on cross-sectional surveys and do not include substantial numbers of American Indians (AI). Secular trends in height and weight reflect general health status. This study describes weight trends and transitions among AI children over a 43-year period.

METHODS

Anthropometric data were obtained from a prospective study conducted in a southwestern US AI population (1965 through 2007). For cross-sectional analysis, 12 377 observations were available from 6529 children across four birth cohorts (1955-1964, 1965-1974, 1975-1984, 1985-1994). Participants were stratified into three age groups: pre- (5-9 years), early (10-13) and late (14-17) adolescence. Longitudinal analyses included 1737 children with one exam in each age group.

RESULTS

In early and late adolescence, weight increased across birth cohorts. Prevalence of obesity among pre-adolescents was 17.5% (95% CI, 15.1%-19.9%) in the 1955-1964 cohort and 33.7% (95% CI, 30.1%-36.4%) in the 1985-1994 cohort. 74% of children overweight in pre-adolescence in the 1985-1994 cohort became obese by late adolescence; in the 1955-1964 cohort, only 43% made this transition.

CONCLUSIONS

This study describes the rising prevalence of childhood obesity. Children obese in pre-adolescence remained obese in late adolescence, stressing the need for early intervention.

Secular changes of pelvis in Croatian perinatal women

The goal of the study was to examine secular changes of pelvic size in parturient women over the 25-year period from 1985 to 2009. Data were collected from randomly selected patients' medical records of 2414 parturient women from four time periods (1985-1986, 1992-1994, 2000-2002, and 2007-2009). Three different pelvic measurements were collected: distantia spinarum, distantia cristarum, and distantia trochanterica. Regression analyses were conducted in order to test predictors of pelvic dimensions. The multivariate analysis of covariance (MANCOVA) was used to test changes in pelvic dimensions over time, with body mass index (BMI) as a covariate. The average size of distantia spinarum, distantia cristarum, and distantia trochanterica was 249.3mm (SD=13.7), 277.9 mm (SD=15.6), and 318.3mm (SD=19.6), respectively. Pelvic dimensions were all positively related to woman's height and pre-pregnancy weight. After controlling for the BMI, there were significant changes in pelvic dimensions over the 25-year period and it was shown that distantia spinarum, cristarum, and trochanterica all increased (F [3,2408]=16.4, p<0.01), especially from the 1992-1994 period to the present. To conclude, parallel with secular changes of weight and height in parturient women, changes in bones are also evident. The size of pelvis in parturient women had significantly enlarged over the 25-year period.

Dietary patterns of Akwesasne Mohawk adolescents

BACKGROUND

Native American youth have greater rates of overweight/obesity than same-aged youth from the general population. Even though dietary shifts are suspected, surprisingly little information exists concerning the dietary patterns of contemporary Native American adolescents.

AIM

This study examines the dietary composition of Native American adolescents residing in upstate New York at the Akwesasne Mohawk Nation. The goal of this investigation is to assess the food patterns of Akwesasne adolescents via a total diet approach. PARTICIPANTS/SETTING AND METHODS: The sample is comprised of 246 Mohawk adolescents between the ages of 10-16.9 years of age residing at the Akwesasne Mohawk Nation. Food frequency data was collected from adolescents via interview during a cross-sectional study investigating their exposure to environmental pollutants.

RESULTS AND CONCLUSION

Nutrient-dilute but energy-dense foods characterize most of the top 10 dietary sources of energy, carbohydrates, and fat. Although micronutrient intakes are by and large adequate in the sample, micronutrients are most often derived from highly fortified food sources. Adolescent diets contain few naturally-occurring sources of many micronutrients, especially folate and iron. A narrow variety of foods dominate the top dietary sources across both macronutrient and micronutrients, strongly suggesting the need for increased dietary diversity within this age group.

Intervention effects on kindergarten and first-grade teachers' classroom food practices and food-related beliefs in American Indian reservation schools

Prevalence of obesity among American Indian children is higher than the general US population. The school environment and teachers play important roles in helping students develop healthy eating habits. The aim of this prospective study was to examine teachers' classroom and school food practices and beliefs and the effect of teacher training on these practices and beliefs. Data were used from the Bright Start study, a group-randomized, school-based trial that took place on the Pine Ridge American Indian reservation (fall 2005 to spring 2008). Kindergarten and first-grade teachers (n=75) from 14 schools completed a survey at the beginning and end of the school year. Thirty-seven survey items were evaluated using mixed-model analysis of variance to examine the intervention effect for each teacher-practice and belief item (adjusting for teacher type and school as random effect). At baseline, some teachers reported classroom and school food practices and beliefs that supported health and some that did not. The intervention was significantly associated with lower classroom use of candy as a treat (P=0.0005) and fast-food rewards (P=0.008); more intervention teachers disagreed that fast food should be offered as school lunch alternatives (P=0.019), that it would be acceptable to sell unhealthy foods as part of school fundraising (P=0.006), and that it would not make sense to limit students' food choices in school (P=0.035). School-based interventions involving teacher training can result in positive changes in teachers' classroom food practices and beliefs about the influence of the school food environment in schools serving American Indian children on reservations.

A community-based intervention to prevent obesity beginning at birth among American Indian children: study design and rationale for the PTOTS study

Eating and physical activity behaviors associated with adult obesity have early antecedents, yet few studies have focused on obesity prevention interventions targeting very young children. Efforts to prevent obesity beginning at birth seem particularly important in populations at risk for early-onset obesity. National estimates indicate that American Indian (AI) children have higher rates of overweight and obesity than children of other races/ethnicities. The Prevention of Toddler Obesity and Teeth Health Study (PTOTS) is a community-partnered randomized controlled trial designed to prevent obesity beginning at birth in AI children. PTOTS was developed to test the effectiveness of a multi-component intervention designed to: promote breastfeeding, reduce sugar-sweetened beverage consumption, appropriately time the introduction of healthy solid foods, and counsel parents to reduce sedentary lifestyles in their children. A birth cohort of 577 children from five AI tribes is randomized by tribe to either the intervention (three tribes) or the comparison condition (two tribes). The strengths and weaknesses of PTOTS include a focus on a critical growth phase, placement in the community, and intervention at many levels, using a variety of approaches.

Overweight and obesity among North American Indian infants, children, and youth

The frequency of overweight and obesity among North American Indian children and youth exceeds that of other ethnic groups in the United States. This observation is based on studies using body mass index as the primary measure of overweight and obesity. In the mid-20th century, there were regional differences among North American Indian groups in sub-adults' size and shape and only a few Southwestern groups were characterized by high rates of overweight and obesity. In most populations, the high prevalence of overweight and obesity developed in the last decades of the 20th century. Childhood obesity may begin early in life as many studies report higher birth weights and greater weight-for-height in the preschool years. Contributing factors include higher maternal weights, a nutritional transition from locally caught or raised foods to store bought items, psychosocial stress associated with threats to cultural identity and national sovereignty, and exposure to obesogenic pollutants, all associated to some degree with poverty. Obesity is part of the profile of poor health among Native Americans in the US and Canada, and contributes to woefully high rates of diabetes, cardiovascular disease, and early mortality. Interventions that are culturally appropriate are needed to reduce weights at all points in the lifespan.

Summer effects on body mass index (BMI) gain and growth patterns of American Indian children from kindergarten to first grade: a prospective study

BACKGROUND

Overweight and obesity are highly prevalent among American Indian children, especially those living on reservations. There is little scientific evidence about the effects of summer vacation on obesity development in children. The purpose of this study was to investigate the effects of summer vacation between kindergarten and first grade on growth in height, weight, and body mass index (BMI) for a sample of American Indian children.

METHODS

Children had their height and weight measured in four rounds of data collection (yielded three intervals: kindergarten, summer vacation, and first grade) as part of a school-based obesity prevention trial (Bright Start) in a Northern Plains Indian Reservation. Demographic variables were collected at baseline from parent surveys. Growth velocities (Z-score units/year) for BMI, weight, and height were estimated and compared for each interval using generalized linear mixed models.

RESULTS

The children were taller and heavier than median of same age counterparts. Height Z-scores were positively associated with increasing weight status category. The mean weight velocity during summer was significantly less than during the school year. More rapid growth velocity in height during summer than during school year was observed. Obese children gained less adjusted-BMI in the first grade after gaining more than their counterparts during the previous two intervals. No statistically significant interval effects were found for height and BMI velocities.

CONCLUSIONS

There was no indication of a significant summer effect on children's BMI. Rather than seasonal or school-related patterns, the predominant pattern indicated by weight-Z and BMI-Z velocities might be related to age or maturation.

TRIAL REGISTRATION

Bright Start: Obesity Prevention in American Indian Children Clinical Trial Govt ID# NCT00123032.

Growth and obesity in 7-year-old Croatian children: secular changes from 1991 to 2008

The study analyses secular changes in body weight, height and body mass index (BMI) in children in the Splitsko-dalmatinska County, Croatia, in the period from 1991 to 2008. The overweight/obesity trends from 1991 to 1999 and from 2000 to 2008 are assessed. The study included three cohorts of healthy 7-year-old children, measured during their regular medical examination before enrolment at school: 1991 (n = 514), 1999 (n = 428) and 2008 (n = 452), in a total of 1,394 children, 686 (49.21%) of whom were girls. Overweight/obesity was defined according to the International Obesity Task Force criteria. From 1991 to 2008, there was a statistically significant rise in body weight and BMI in boys and girls (1.47 vs 1.50 kg; 0.55 vs 0.75 kg) and height in boys (1.4 cm). In 2008, the girls were 0.14 kg heavier and 0.39 cm taller than the girls of the same age measured in 1999, but their BMI was lower by 0.02 units. The frequency of obesity rose from 1991 to 2008 by 1.4 times in boys and 1.7 times in girls. The prevalence of obesity in girls rose from 1991 to 1999 (from 4.3% to 8.6%), but in 2008, it fell (7.1%). The prevalence of obesity in boys fell in 1999 (from 4.3% to 3.9%) but rose in 2008 (6.2%). The values of body weight, height and BMI in the observed population moved from 1991 to 2008 towards higher WHO standard values, which is descriptive of the problem of obesity and supports the need to consider the choice of cut-off points for obesity/overweight in local and national studies. In conclusion, the slowdown noticed in secular changes in body weight and BMI is encouraging and shows the importance of continuous paediatric health care for children, combined with an altered attitude in society towards obesity in children.

Linking farmers to community stores to increase consumption of local produce: a case study of the Navajo Nation

OBJECTIVE

To understand the barriers to farmer participation in Farm-to-Table (F2T) programmes and to identify possible solutions to these obstacles.

DESIGN

Cross-sectional analysis of farmer perspectives on F2T programmes.

SETTING

Three service units on the Navajo Nation (Chinle, Tuba City and Fort Defiance).

SUBJECTS

Forty-four Navajo farmers.

RESULTS

Most participants reported that farming on the Navajo Nation is getting harder (61 %) but that it is very important to maintain Navajo farming traditions (98 %). A modest number of farmers (43 %) expressed interest in participating in an F2T programme. All farmers reported that childhood obesity was a very serious or serious problem in the Navajo Nation. The farmers expressed support for an F2T programme if key barriers to farming, including water access and pest control, could be addressed. Key barriers to participation identified included lack of fruits and vegetables to sell, sale price of crops and lack of certification of produce by the US Food and Drug Administration.

CONCLUSIONS

Navajo farmers are aware of the burden of childhood obesity on the Navajo Nation and feel that an F2T programme could be beneficial. To successfully implement a Farm-to-Table programme, the barriers to participation identified will need to be addressed.

Undernutrition and obesity in indigenous children: epidemiology, prevention, and treatment

Over the past 50 years there has been a shift in nutritional problems amongst Indigenous children in developed countries from under-nutrition and growth faltering to overweight and obesity; the major exception is small numbers of Indigenous children predominately living in remote areas of Northern Australia. Nutritional problems reflect social disadvantage and occur with disproportionately high incidence in all disadvantaged subgroups. There is limited evidence of benefit from any strategies to prevent or treat undernutrition and obesity; there are a limited number of individual studies with generalizable high grade evidence of benefit. Potential solutions require a whole of society approach.

Racial and ethnic disparities in medical and dental health, access to care, and use of services in US children

BACKGROUND

Not enough is known about the national prevalence of racial/ethnic disparities in children's medical and dental care.

OBJECTIVE

The purpose of this work was to examine racial/ethnic disparities in medical and oral health, access to care, and use of services in a national sample.

METHODS

The National Survey of Children's Health was a telephone survey in 2003-2004 of a national random sample of parents and guardians of 102,353 children 0 to 17 years old. Disparities in selected medical and oral health and health care measures were examined for white, African American, Latino, Asian/Pacific Islander, Native American, and multiracial children. Multivariate analyses were performed to adjust for primary language at home, age, insurance coverage, income, parental education and employment, and number of children and adults in the household. Forty measures of medical and oral health status, access to care, and use of services were analyzed.

RESULTS

Many significant disparities were noted; for example, uninsurance rates were 6% for whites, 21% for Latinos, 15% for Native Americans, 7% for African Americans, and 4% for Asians or Pacific Islanders, and the proportions with a usual source of care were as follows: whites, 90%; Native Americans, 61%; Latinos, 68%; African Americans, 77%; and Asians or Pacific Islanders, 87%. Many disparities persisted for > or = 1 minority group in multivariate analyses, including increased odds of suboptimal health status, overweight, asthma, activity limitations, behavioral and speech problems, emotional difficulties, uninsurance, suboptimal dental health, no usual source of care, unmet medical and dental needs, transportation barriers to care, problems getting specialty care, no medical or dental visit in the past year, emergency department visits, not receiving mental health care, and not receiving prescription medications. Certain disparities were particularly marked for specific racial/ethnic groups: for Latinos, suboptimal health status and teeth condition, uninsurance, and problems getting specialty care; for African Americans, asthma, behavior problems, skin allergies, speech problems, and unmet prescription needs; for Native Americans, hearing or vision problems, no usual source of care, emergency department visits, and unmet medical and dental needs; and for Asians or Pacific Islanders, problems getting specialty care and not seeing a doctor in the past year. Multiracial children also experienced many disparities. CONCLUSIONS; Minority children experience multiple disparities in medical and oral health, access to care, and use of services. Certain disparities are particularly marked for specific racial/ethnic groups, and multiracial children experience many disparities.

Overweight and obesity in a rural Amerindian population in Oaxaca, Southern Mexico, 1968-2000

The purpose of this study was to evaluate secular change in the prevalence of overweight and obesity in a rural Zapotec Indian community in southern Mexico between 1968 and 2000. Cross-sectional surveys of children 6-13 years, adolescents 13-17 years, and adults 19 years of age and older resident in a rural community in Oaxaca were conducted in 1968/1971, 1978, and 2000. Individuals present in the 1968, 1978, and 2000 surveys provided a small longitudinal component. Height and weight were measured; the BMI was calculated. International criteria for overweight and obesity were used. Overweight and obesity were virtually absent in school children 6-13 years in 1968 and 1978 and in adolescents in 1978. Small proportions of children (boys, 5%; girls, 8%) and adolescents (boys, 3%; girls, 15%) were overweight in 2000; two children (1%) and no adolescents were obese. Among adults, 7% of males and 19% of females were overweight and <1% of males and 4% of females were obese in 1971/1978, but 46% of males and 47% of females were overweight; and 5% of males and 14% of females were obese in 2000. The trends for children, adolescents, and adults were confirmed in the longitudinal subsamples. In conclusion, overweight and obesity are not presently a major problem in children and adolescents in this rural Zapotec community. Overweight, in particular, and to a lesser extent obesity have increased in prevalence among adults since the late 1970s. The results suggest adulthood as a critical period for onset of overweight and obesity in this sample.

The nutrition transition in American Indians

The purpose of this article was to examine whether a nutritional transition has occurred among American Indians (AI) by evaluating related articles and government health statistics. Findings indicate that although the primary health risk for the AI population around 1970 was undernutrition, now there is an obesity epidemic among all age groups that is associated with a loss of traditional food practices and reduced physical activity. Deaths caused by cardiovascular disease, diabetes mellitus, and cancer have outpaced death from infectious disease. With abundant high-energy foods and limited physical activity, the acculturated environment has resulted in obesity and increased mortality from chronic diseases. To improve AI health and survival, the obesity epidemic must be approached in a concerted, culturally appropriate manner with encouragement of traditional foods and safe opportunities for physical activity.

Estado nutricional e fatores associados à estatura de crianças da Terra Indígena Guarita, Sul do Brasil

O estado nutricional de crianças menores de cinco anos e fatores associados à estatura foram estudados usando dados de um programa para controle da desnutrição e mortalidade na Terra Indígena Guarita, Rio Grande do Sul, Brasil, 2001/2002. Índices antropométricos foram calculados em escores-z da referência CDC/2000. Na primeira avaliação pelo programa, 34,7%, das crianças apresentavam baixa estatura, 12,9% baixo peso para idade, 4,2% baixo peso para estatura e 8,7% sobrepeso. Baixa estatura foi mais prevalente em meninos e maiores de um ano. Modelos de regressão linear múltipla sugerem que a altura foi, em média, menor quando a água para alimentação era de fonte/poço/rio (p = 0,046), não havia geladeira para conservar alimentos (p = 0,021), a mãe era menor de 16 anos ao nascimento do mais velho entre os filhos menores de cinco anos (p = 0,019) e analfabeta (p = 0,083). O destino dos dejetos evidenciou efeito apenas no modelo bruto. Não houve evidência de efeito do número de filhos menores de cinco anos. Políticas de inclusão social e provisão de recursos sociais e de saúde são potencialmente relevantes para a saúde e nutrição nessa população.

Intrafamilial correlates of overweight and obesity in African-American and Native-American grandparents, parents, and children in rural Oklahoma

Study objectives were to describe overweight in Native-American and African-American three-generation families and to examine relationships among the individual variables of body mass index (BMI), television hours, and activity levels. Forty-four Native-American and 40 African-American families were recruited from 10 sites through community contacts at health, senior, community, and tribal centers. Ninety percent of parents and grandparents had BMIs above 25.0. Forty-two percent of African-American and 61% of Native-American children had a BMI above the 85th percentile. More than 35% of total energy was from fat. Significant correlations were observed between parent and child BMI and television hours, grandparent and child BMI, and grandparent and parent activity with child television hours. Sedentary caretakers facilitate more television viewing and less activity in children. Dietetics professionals should plan family-friendly daily physical activities, like walking, and diets lower in fat, sugar, and total energy, with higher intakes of fresh fruits and vegetables, whole grains, and low-fat dairy products for children and caretakers.

Overweight in children: definitions, measurements, confounding factors, and health consequences

The epidemic of childhood overweight continues to grow at staggering rates, increasing nearly four-fold between 1963 and 2000. Children that are overweight are more apt to be overweight adults and are more likely to suffer adverse health consequences associated with excess weight. Nurses have a unique presence in the healthcare environment to assess children for overweight, provide parent/child nutritional education, and conduct obesity-related research. This article provides an overview of the current body of literature surrounding the definition and measurement of overweight and the morbidity association with childhood overweight.

Growth status and obesity of Hopi children

The purpose of this study was to examine the growth status and prevalence of underweight, overweight, and obesity in Hopi children. Subjects were 263 (117 males, 146 females) Hopi children 6-12 years of age. Stature and mass were measured and the body mass index (BMI) was calculated. Body size variables were plotted relative to age- and sex-specific reference data and the prevalence rates for underweight, overweight, and obesity were estimated using the BMI as the criterion. Age-specific sex differences were compared using independent samples t-tests. In both sexes, mean age-specific stature appeared to be relatively stable around the 50th percentile of reference values. Mean age-specific mass appeared to be relatively stable between the 50th and 90th percentiles of the reference values, while the mean BMI tended to fluctuate about the 85th percentile. Approximately 23% of Hopi children were classified as overweight and an additional 24% were classified as obese. Only two subjects were categorized as underweight. The results are consistent with other reports that childhood obesity is a serious public health concern among Native Americans. Further study is warranted to examine the causes of the high prevalence rates of pediatric obesity among Native Americans and the effectiveness of prevention and intervention programs.

Obesity in American-Indian children: prevalence, consequences, and prevention

BACKGROUND

American Indians of all ages and both sexes have a high prevalence of obesity. The health risks associated with obesity are numerous and include Type 2 diabetes mellitus, hypertension, dyslipidemia, and respiratory problems. Obesity has become a major health problem in American Indians only in the past few generations and it is believed to be associated with the relative abundance of high-fat, high-calorie foods and the rapid change from active to sedentary lifestyles.

METHODS

The authors reviewed selected literature on prevalence of obesity in American-Indian children, and health consequences of obesity.

RESULTS

Obesity is now one of the most serious public health problems facing American-Indian children, and it has grave implications for the immediate and long-term health of American-Indian youth. Unless this pattern is reversed, American-Indian populations will be burdened by an increased incidence of chronic diseases. Intervention studies are urgently needed in American-Indian communities to develop and test effective strategies for obesity prevention and treatment.

CONCLUSIONS

To be effective, educational and environmental interventions must be developed with full participation of the American-Indian communities.

Impact of the Pathways intervention on dietary intakes of American Indian schoolchildren

BACKGROUND

The Pathways study was a randomized, 3-year trial of obesity prevention in American Indian Children. An important goal of the Pathways intervention was to significantly decrease the percentage of calories eaten as fat by the intervention children, relative to controls. This paper reports the effects of the Pathways intervention on dietary intake.

METHODS

Two types of dietary data were analyzed from random samples of children in 41 schools: direct observation of school lunch intake at baseline (2nd grade) and follow-up (5th grade) (n=470), and 24-hour dietary recalls at follow-up only (n=620). Nutrient contents of school meals and recalls were calculated by NDS and NDS-R software (University of Minnesota), using vendor products and recipes from each school.

RESULTS

Based on lunch observations, the intervention was associated with significant decreases in mean percentage of calories from total fat (3.6%) and saturated fat (2.1%) relative to controls, and a significant increase in the percentage of calories from total carbohydrate (3.7%). Compared with the control children, intervention children reported significantly smaller 24-hour intakes of energy (263 kcal), protein (9.5 g), total fat (15.1 g), saturated fat (6.0 g), and polyunsaturated fat (2.3 g); and as a percent of calories, total fat (2.5%) and saturated fat (1.1%). Mean intake of carbohydrates as a percentage of calories was significantly greater in intervention children by 2.5%, compared with controls.

CONCLUSIONS

The Pathways intervention successfully reduced the intake of percent calories from fat and saturated fat, at school lunch and over the whole day.

Obesity and psychiatric disorder: developmental trajectories

OBJECTIVES

To identify age-related trajectories of obesity from childhood into adolescence, and to test the association of these trajectories with the development of psychiatric disorders (conduct disorder, oppositional defiant disorder, attention-deficit/hyperactivity disorder, substance abuse, depression, and anxiety).

METHODS

White children (N = 991) 9 to 16 years old from the Great Smoky Mountains Study, a representative sample of rural youth, were evaluated annually over an 8-year period for height, weight, psychiatric disorder, and vulnerabilities for psychiatric disorder. Longitudinal analyses on the repeated measures data were conducted using developmental trajectory models and generalized estimating equation models.

RESULTS

Obesity was 3 to 4 times more common than expected from national rates using Centers for Disease Control and Prevention 2000 criteria. Four developmental trajectories of obesity were found: no obesity (73%), chronic obesity (15%), childhood obesity (5%), and adolescent obesity (7%). Only chronic obesity was associated with psychiatric disorder: oppositional defiant disorder in boys and girls and depressive disorders in boys.

CONCLUSIONS

In a general population sample studied longitudinally, chronic obesity was associated with psychopathology.

Obesity correlates with increased blood pressures in urban Native American youth

Although obesity is a growing problem with Native American youth living on reservations, little research has been conducted examining the prevalence of obesity and correlations between age, body composition, dietary intake, and blood pressures (BP) for urban Native youth. The purpose of this study was to investigate the relationship of these variables in urban Native American youth. Height and weight were measured for 155 Native American youth, age 5-18 years, and the body mass index (BMI) was calculated and classified into percentile categories. Skinfold thicknesses at the biceps, triceps, suprailiac, and subscapular sites, arm and waist circumferences, and systolic (SBP) and diastolic (DBP) blood pressures were also measured. There was a high proportion of obesity (>95 percentile) for youth in all age groups. The prevalence was 38% for the 5-10-year-olds and 45% for the 11-18-year-olds youth. There were no significant correlations between SBP and DBP and dietary variables. Mean SBP and DBP increased with increasing BMI percentiles. Stepwise regression analyses showed that waist circumference, age, and BMI were strong predictors for SBP, while waist circumference and age were predictors for DBP in the total sample. The findings suggest that overweight/obesity is very prevalent among urban Native American youth and the increased adiposity is associated with increased SBP and DBP.

Who is becoming overweight during the elementary school years?

OBJECTIVE

To determine the risk of becoming overweight for every first grader during the elementary school years and to determine whether the overall risk of becoming overweight for first graders is increasing.

STUDY DESIGN

A descriptive study using school-based surveys of 12,588 boys and 12,264 girls who entered elementary school between 1989 and 1994. Six years later, the follow-up survey was conducted. Overweight was defined using the BMI percentile cut-off points.

MEASUREMENTS

For every 5th percentile rank of first graders, the odds ratio for becoming overweight at seventh grade was calculated. A hockey stick regression analysis and the yearly trend of the risk for becoming overweight at 7th grade were also investigated.

RESULTS

For overweight children in first grade, the odds ratio for staying at the same level was extremely high in both boys (35.0) and girls (63.9). The threshold effects of the BMI percentile value at first grade for becoming overweight were the 81st and 87th percentiles for boys and girls, respectively, according to the hockey stick model. The overall risk for becoming overweight significantly increased in boys during the study period (P=0.009).

CONCLUSION

The present study determined the exact level of the risk for becoming overweight for every first grader at a different BMI percentile rank. The risk of overweight children in first grade who stayed at the same level at seventh grade was higher in girls than in boys. On the other hand, the trend of the entire population for becoming overweight presents only in boys. The different pattern of the trend of population for becoming overweight by sex during elementary school period may provide evidence to understand and predict overweight in adolescents and adults.

Assessing risk factors for obesity between childhood and adolescence: I. Birth weight, childhood adiposity, parental obesity, insulin, and leptin

OBJECTIVE

To assess the effects of body weight, body composition, parental obesity, and metabolic variables on the development of obesity in a large cohort of 5-year-old Native American children with a high propensity for obesity.

METHODS

During the summer months of 1992 to 1995 and again 5 years later, 138 (65 boys and 73 girls) 5-year-old Pima Indian children were studied. Height; weight; body composition; parental obesity; and fasting plasma insulin, glucose, and leptin concentrations were determined at baseline and follow-up. Linear regression models were used to assess the effect of the baseline variables on the development of obesity.

RESULTS

At both 5 and 10 years of age, Pima Indian children were heavier and fatter than an age- and gender-matched reference population. All anthropometric and metabolic variables tracked strongly from 5 to 10 years of age (r > or = 0.70). The most significant determinant of percentage of body fat at 10 years of age was percentage of body fat at 5 years of age (R(2) = 0.53). The combined effect of high maternal body mass index, elevated fasting plasma leptin concentrations, and low fasting plasma insulin concentrations at baseline explained an additional 4% of the total variance in adiposity at follow-up.

CONCLUSIONS

Although parental obesity and metabolic variables such as insulinemia and leptinemia at baseline account for a small percentage of the variance in adiposity at follow-up, early childhood obesity is the dominant predictor of obesity 5 years later. These results suggest that strategies to prevent childhood obesity must be initiated at a very early age.

Ethnic issues in the epidemiology of childhood obesity

Childhood obesity may be seen as a marker for high-risk dietary and physical inactivity practices. Recent increases in the prevalence of overweight and obesity among American children are not limited to one age, gender, or ethnic group, which suggests that unique behaviors of the members of various racial or ethnic subgroups of the population are unlikely to be the major contributing factors. Rather, it seems that environmental changes promoting increased energy intake and decreased energy output are occurring and have widespread impact on children from various backgrounds. Although no ethnic group is immune from the current shift in energy balance, differential rates of overweight seem to exist among ethnic groups. National probability samples of African-American, Hispanic, and white children in the United States provide clear evidence that white children are at lower risk for childhood overweight than are African-American or Hispanic children. Of concern is the lack of national data on the prevalence of overweight and obesity for Native-American and Asian-American groups. Also of concern is the aggregation of racial and ethnic subgroups, which may render prevalence rates meaningless. This possibility is clearly true with some surveys of weight status that combine diverse populations, such as Asians and Pacific Islanders, into one group. The high rates of obesity in African-American, Hispanic, and Native-American children are of concern. Although parental SES is associated inversely with childhood obesity among whites, higher SES does not seem to protect African-American and Hispanic children against obesity. In these groups, childhood obesity does not seem to be associated significantly with parental income and education. Health consequences of childhood obesity include a higher prevalence of type 2 diabetes and an increased risk for adverse levels of lipids, lipoproteins, and blood pressure. The effects of recently reported unprecedented levels of childhood overweight on subsequent risk for obesity in middle age are not known until future longitudinal data can be collected. It seems likely, however, that future health consequences of current early and severe childhood obesity will be staggering. Funding for adult follow-up of longitudinal studies of high-risk African American, Hispanic, and Native-American children is needed urgently to provide information on the long-term effects of childhood obesity. Halting the obesity epidemic is a formidable task, but the success in recent decades of drastically reducing childhood undernutrition offers hope and should spur similar action and leadership efforts. Promotion of efforts to reduce excess caloric intake with efforts to increase energy expenditure should receive paramount attention in the design of health programs. Given the relatively few published obesity-prevention and treatment studies that are designed to address specific cultural issues, it is important to promote the development of culturally appropriate intervention strategies that are shown to be effective among youth of diverse backgrounds. Although the dietary and activity goals will be similar, parental, family, and community messages and techniques grounded in cultural traditions and norms will be different for each ethnic group. This approach is crucial in the United States, a country with an increasingly diverse population.