Body mass index during childhood, adolescence and young adulthood in relation to adult overweight and adiposity: the Fels Longitudinal Study

Age-dependent regulation of lipogenesis in human and rat adipocytes

The regulation of adipocyte metabolism is of importance for adipose tissue growth and therefore also for the development of obesity. This study was designed to investigate the regulation of basal and insulin-induced lipogenesis, glucose transport, and glucose transporter protein expression in human and rat adipocytes from different age groups. The study included 21 infants, 21 children, nine adults, and 80 male weaned and 20 male adult Fischer rats. The lipogenesis experiments were performed under conditions at which glucose transport is rate limiting. Basal lipogenesis was approximately three times higher in infants and children than in adults, whereas insulin-induced lipogenesis was two times higher in infants than in children and adults. In rats, basal lipogenesis, insulin-induced lipogenesis, and insulin sensitivity were two times higher in weaned than in adult animals. Moreover, basal and insulin-induced glucose transport were two times higher in weaned than in adult rats. No differences were detected in GLUT1 or GLUT4 content between any of the age groups in human or in rat adipocytes. In conclusion, basal and insulin-stimulated lipogenesis are increased in adipocytes early in life. This may promote adipose tissue growth in early age. The data indicate that age-dependent variation in basal and insulin-stimulated lipogenesis is differently regulated.

Low income Russian families adopt effective behavioral strategies to maintain dietary stability in times of economic crisis

The social, political and economic reforms of 1992 in Russia led to a decade of rising income inequality, unemployment and economic crises, the most severe of which occurred in 1998. This study assesses dietary trends for children in low and high income households during this politically and economically unstable period from 1994 to 2000. Several possible food-related behaviors were also assessed to evaluate coping strategies adopted in the face of decreasing economic stability. Low income children maintained a steady energy intake per kilogram weight throughout the study period (251.0-259.4 kJ/kg), whereas intake for high income children increased significantly to a per capital average of 297.1 kJ/kg by 2000. At the food group level, the trend in per capita intake for all food groups was maintained for low income children except for a 22% decrease in meat and poultry consumption (P < 0.01). Per capita intake increased over time for dairy products and eggs in the high income group (P < 0.01). A decrease in cost per kJ (rubles/kJ) was observed for both low and high income families (P < 0.01). These data suggest that Russian households were able to conserve the diet structure for children by using what appear to be food-related behavioral mechanisms during periods of economic crisis.

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

OBJECTIVE

To examine genetic loci linked to a long-term burden and trend of obesity traits, such as body mass index (BMI), from childhood to adulthood.

DESIGN

: Longitudinal study using serial measurements of BMI from childhood.

SUBJECTS

A total of 782 unselected white siblings (representing 521 full and 39 half sib-pairs) from 342 families enrolled in the Bogalusa Heart Study.

MEASUREMENTS

A total of 357 microsatellite markers with an average spacing of 9.0 cM spanning the 22 autosomal chromosomes were typed. A quadratic growth curve was developed using a random effects model based on serial measurements of BMI from childhood to adulthood. The serial changes in BMI were measured in terms of long-term burden (area under the curve (AUC) divided by follow-up years) and the long-term trend (incremental AUC, calculated as total AUC-baseline AUC).

RESULTS

Heritability estimates of long-term measures were 0.78 for total AUC and 0.43 for incremental AUC. In a variance-component-based multipoint linkage analysis with SOLAR, linkage to the long-term measures of BMI was observed on chromosomes 1, 5, 7, 12, 13 and 18. For total AUC, LOD scores were 3.0 at 110 cM on chromosome 12, 2.9 at 26 cM and 2.4 at 52 cM on chromosome 7, and 2.2 at 126 cM on chromosome 5. For incremental AUC, LOD scores were 2.9 at 26 cM, 2.1 at 97 cM and 2.3 at 110 cM on chromosome 12, 2.2 at 69 cM on chromosome 7, 2.2 at 91 cM and 2.5 at 150 cM on chromosome 1, 2.0 at 119 cM on chromosome 5, 2.0 at 54 cM on chromosome 13 and 2.0 at 7 cM on chromosome 18. Several important obesity-related candidate genes are located in the regions or near the markers showing positive linkage.

CONCLUSION

Linkage evidence found in this study indicates that regions on these chromosomes might harbor genetic loci that affect the propensity to develop obesity from childhood.

Bariatric surgery for severely overweight adolescents: concerns and recommendations

As the prevalence of obesity and obesity-related disease among adolescents in the United States continues to increase, physicians are increasingly faced with the dilemma of determining the best treatment strategies for affected patients. This report offers an approach for the evaluation of adolescent patients' candidacy for bariatric surgery. In addition to anthropometric measurements and comorbidity assessments, a number of unique factors must be critically assessed among overweight youths. In an effort to reduce the risk of adverse medical and psychosocial outcomes and increase compliance and follow-up monitoring after bariatric surgery, principles of adolescent growth and development, the decisional capacity of the patient, family structure, and barriers to adherence must be considered. Consideration for bariatric surgery is generally warranted only when adolescents have experienced failure of 6 months of organized weight loss attempts and have met certain anthropometric, medical, and psychologic criteria. Adolescent candidates for bariatric surgery should be very severely obese (defined by the World Health Organization as a body mass index of > or =40), have attained a majority of skeletal maturity (generally > or =13 years of age for girls and > or =15 years of age for boys), and have comorbidities related to obesity that might be remedied with durable weight loss. Potential candidates for bariatric surgery should be referred to centers with multidisciplinary weight management teams that have expertise in meeting the unique needs of overweight adolescents. Surgery should be performed in institutions that are equipped to meet the tertiary care needs of severely obese patients and to collect long-term data on the clinical outcomes of these patients.

Cardiovascular disease risk factors among children of different socioeconomic status in Istanbul, Turkey: directions for public health and nutrition policy

OBJECTIVES

The aim of the current study was to examine the influence of socioeconomic status (SES) on physiological (lipid profile, obesity indices) and behavioral (dietary habits, physical activity) cardiovascular disease (CVD) risk factors among primary schoolchildren in Istanbul.

DESIGN

Cross sectional study.

SETTING

One private school and two public schools from different SES districts in Istanbul.

PARTICIPANTS

510 randomly selected children aged 12 and 13 years old (257 boys, 253 girls).

RESULTS

The prevalence of overweight (15.2%) and the energy intake (p < 0.001 and p < 0.05 for boys and girls respectively) were found to be higher for the middle/high SES group for both genders. Regarding biochemical indices, middle/high SES children had higher values of High Density Lipoprotein-cholesterol (HDL-C) (p < 0.001 and p < 0.05 for boys and girls respectively) and lower values of TC/HDL-C ratio and LDL-C/HDL-C ratio (p < 0.05 and p < 0.001 for boys and girls respectively). This could be attributed to the higher physical activity levels observed for middle/ high SES children (p < 0.001).

CONCLUSION

The findings of the current study revealed a coexistence of both overweight and higher energy intake in middle/high SES children, as well as a coexistence of underweight and lower physical activity levels in low SES children. These observations should guide the public health policy in developing appropriate intervention strategies to efficiently tackle these health and social issues early in life.

Associations between blood pressure and overweight defined by new standards for body mass index in childhood

BACKGROUND

Using data from a longitudinal study of young Australians, we applied recent international standards for overweight and obesity to examine associations with blood pressure (BP) and to determine the prevalence and degree of tracking of overweight and obesity. We also aimed to examine socioeconomic status in relation to these variables.

METHODS

BP, height, and weight were measured at 3-year intervals from age 9 to 18, and then at 25 years of age in a Western Australian cohort. At these stages, data were available for 1,036, 1,310, 618, 615 and 600 individuals, respectively.

RESULTS

We found 10% of 9-year-old males to be overweight or obese, while among 12-year-olds, 13% were overweight or obese; at age 15, and still at age 18, overweight or obesity was registered in 17% of this population and it rose to 42% among the 25-year-old young men. The percentage of overweight or obese females at these stages was initially 8, then 12 (at age 12), 11 (at age 15), 14 (at age 18) and finally 32. Overweight or obesity tracked to young adult life in 16% of those overweight or obese at 9, 24% at 12, 34% at 15 and 35% at 18 years. Systolic BP was significantly higher in the overweight or obese except in 12-year-olds. At the age of 25 years, 53% of men had high normal BP or were hypertensive.

CONCLUSIONS

Increasing overweight or obesity in young Australians, consistent with international trends, has serious health implications. Overweight and obesity show tracking and are predictors of higher blood pressure, except in early adolescence.

Attitudes, practices, and concerns about child feeding and child weight status among socioeconomically diverse white, Hispanic, and African-American mothers

Parents play an important role in the development of their children's eating behaviors. We conducted 12 focus groups (three white, three African-American, and three Hispanic-American low-income groups; three white middle-income groups) of mothers (N=101) of 2- to less than 5-year-old children to explore maternal attitudes, concerns, and practices related to child feeding and perceptions about child weight. We identified the following major themes from responses to our standardized focus group guide: 12 groups wanted to provide good nutrition, and most wanted children to avoid eating too many sweets and processed foods; 12 groups prepared foods their children liked, accommodated specific requests, and used bribes and rewards to accomplish their feeding goals (sweets were commonly used as bribes, rewards, or pacifiers); and 11 of 12 groups believed their children were prevaricating when they said they were full and mothers encouraged them to eat more. The common use of strategies that may not promote healthful weight suggests work is needed to develop culturally and socioeconomically effective overweight prevention programs. Further study is needed to verify racial/ethnic or income differences in attitudes, practices, and concerns about child feeding and perceptions of child weight.

A multidisciplinary approach to the adolescent bariatric surgical patient

PURPOSE

Pediatric obesity is an epidemic in the United States. As of yet, no surgical programs specifically dedicated to the management of clinically severely obese adolescents exist. The purpose of this report was to describe the establishment and early experience of a multidisciplinary Comprehensive Weight Management Center (CWMC) in a free-standing children's hospital.

METHODS

With input from an ethicist, gastroenterologist, pulmonologist, endocrinologist, and adolescent medicine physician, guidelines for patient selection, evaluation, and bariatric surgical management were developed and implemented. Roux-en-Y gastric bypass (RYGBP) surgery has been performed using open and laparoscopic techniques.

RESULTS

The average age and body mas index (BMI) for 79 patients referred to the CWMC has been 16 years and 54 kg/m2, for boys and 17 years and 51 kg/m2 for girls. Twenty-five percent have been considered appropriate for RYGBP, 25% have not met criteria for surgery, and 50% are being evaluated. Ten patients who have undergone RYGBP had comorbidities of their obesity, including type 2 diabetes mellitus (DM), obstructive sleep apnea syndrome (OSAS), pulmonary embolism, hypertension, dyslipidemias, and depression. Clinically significant weight loss with resolution of comorbidities has occurred in all patients. Significant complications have included leak from the gastric remnant, DVT, partial roux limb obstruction, and micronutrient deficiency.

CONCLUSIONS

RYGBP is an effective means to treat obesity-related morbidity in the adolescent. A multidisciplinary team of pediatric specialists is needed for optimal preoperative decision making and postoperative management. Results have been satisfactory and justify a clinical trial to confirm the safety and efficacy of bariatric surgery in the adolescent population.

Chicago project uses ecological approach to obesity prevention

CLOCC may be useful as a model for local, cooperative, overweight-prevention efforts that involve researchers, clinicians, and public health advocates in complementary and shared work. It employs an ecological approach and is guided by an understanding of critical periods in the development of overweight in childhood.

The Atherosclerosis Risk in Young Adults (ARYA) study: rationale and design

INTRODUCTION

Despite recent advances in treatment, cardiovascular disease (CVD) is still health problem number one in western societies. Aiming at specific prevention strategies for high-risk individuals and shifting the available prevention programs towards younger age groups might increase the success of primary prevention. However, before addressing age-specific prevention programs, more insight in the determinants of early vascular damage and increased cardiovascular risk is warranted as well as insight in determinants increased cardiovascular risk, including vascular damage, at an early age. The Atherosclerosis Risk in Young Adults (ARYA) study was specifically designed to address this issue.

OBJECTIVES

The ARYA study started off with studies evaluating (1) whether it is possible to predict cardiovascular risk at young adulthood by routinely measured adolescent data, and (2) evaluating the role of birth characteristics and adolescent characteristics to the development of vascular damage at young adulthood.

METHODS

The ARYA study comprises of two cohorts of young adults. The Utrecht cohort includes 750 young adults, aged 27-30 years. The Hague-cohort includes 261 young adults born between 1963 and 1968. Data on birth characteristics, growth in early infancy as well as adolescent anthropometry, blood pressure, lipids, body mass index were obtained from the original medical records of the Municipal Health Service. In 1999/2001, the extent of subclinical vascular damage was measured using carotid wall thickness and aortic stiffness. Also, data on adult cardiovascular risk profile, bone density and central blood pressure were assessed, fasting blood was drawn and timed overnight urine samples were collected.

CONCLUSION

The ARYA study is aimed to provide data on early determinants of cardiovascular risk, including vascular damage, at an early age. This knowledge enhances the understanding of atherosclerosis development and CVD risk and is needed to improve the available primary prevention programs.

A comparison of laparoscopic adjustable gastric banding in adolescents and adults

BACKGROUND

Laparoscopic adjustable gastric banding (AGB) induces effective weight loss in adults, but its efficacy in adolescents has yet to be determined.

METHODS

Since 1996, data have been collected prospectively on all patients undergoing laparoscopic AGB procedures performed at our hospital by a single surgeon (G.F.). Patients <20 years old at surgery (adolescents) were compared with- patients >20 years old (adults) who were matched for sex and body mass index (BMI).

RESULTS

Seventeen adolescents with a median age of 17 years (range, 12-19) and a BMI of 42.2 kg/m2 (range, 30.3-70.5) were compared to 17 adults with a median age of 41 years (range, 23-70) and a BMI of 41.8 kg/m2 (range, 30.1-71.5). There were no significant differences between the adolescents and the adults in complications or weight loss. The BMI dropped to 30.1 kg/m2 (range, 22.6-39.4) in adolescents and 33.1 kg/m2 (range, 28.4-41.3) in adults at 2-month follow-up.

CONCLUSION

Laparoscopic AGB is as effective in adolescents as it is in adults.

Rapid weight gain during infancy and obesity in young adulthood in a cohort of African Americans

BACKGROUND

Obesity is increasing in the United States. Evidence-based prevention is a public health priority and should target well-defined risk factors and critical periods.

OBJECTIVE

We tested the hypothesis that rapid weight gain during early infancy is associated with obesity in African American young adults, a group at increased risk of obesity.

DESIGN

A cohort of 300 African Americans born at full term was followed from birth to 20 y of age. A pattern of rapid weight gain was defined as an increase in weight-for-age > or = 1 SD between birth and 4 mo.

RESULTS

About 29% of subjects had a pattern of rapid weight gain during infancy; 8% were obese [body mass index (in kg/m(2)) > or = 30] at age 20 y. One-third of the obesity at age 20 y could be attributed to rapid weight gain in the first 4 mo of life. After adjustment for confounding factors, subjects with rapid weight gain during early infancy were more likely to become obese at age 20 y (odds ratio = 5.22; 95% CI: 1.55, 17.6; P = 0.008). The results were confirmed by using a combination of body mass index and skinfold thickness (odds ratio = 6.72; 95% CI: 1.93, 23.4; P = 0.003).

CONCLUSIONS

The results of the present study provide evidence that a pattern of rapid weight gain during early infancy is associated with obesity not only in childhood but also in young adulthood. We propose that early infancy constitutes a critical period for the development of obesity. Mechanisms of action and prevention strategies require further investigation.

Critical periods in human growth and their relationship to diseases of aging

It has long been recognized that there are "critical periods" during mammalian development when exposure to specific environmental stimuli are required in order to elicit the normal development of particular anatomical structures or their normal functioning. The responses of the organism to these stimuli depend on a specific level of anatomical maturation and a state of rapid anatomical and/or functional change. This discussion of critical periods in growth is not confined to the classic definition of a narrow time frame of development during which a particular environmental threshold or limit must exist for normal growth and function to ensue. Using both auxological and epidemiological approaches, we suggest a lifespan perspective which encompasses accumulating and interacting risks that are manifest from prenatal life onward. By understanding the process of growth development, and by scrutinizing the growth process, early variations that lead to later disease can be identified. Here we review a significant amount of the evidence that links exposure during growth to later morbidity and mortality. The fetus appears to respond to insults during the prenatal period through the process of "programming," which has short-term survival advantages but may have a long-term disadvantage in that it is associated with cardiovascular disease, hypertension, type II diabetes, and later obesity. Low birth weight combined with rapid postnatal growth during infancy also appears to be associated, for instance, with later childhood and adult sequelae in terms of glucose tolerance and obesity. Independent of birth weight, the timing of adiposity rebound during mid-childhood also predicts later obesity. The timing, magnitude, and duration of adolescent growth and maturationare associated with critical body composition changes, including the normal acquisition of body fat and bone mineralization. In particular, the acquisition of appropriate peak bone mass is critical in determining the later risk of osteoporosis. A putative causal mechanism linking early growth variation to later chronic disease risk through telomeric attrition is discussed. The obligatory loss of telomeric DNA with each cell division serves as a mitotic clock and marks the rate of growth and repair processes in the cell. Although much more work is required, existing studies support the notion that telomere shortening is not only a clock of cellular division, but also marks relative growth rate, as well as contributing to common degenerative processes of aging through its impact on cellular senescence.

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 in a cohort of black Jamaican children as estimated by BMI and other indices of adiposity

OBJECTIVE

To examine the relationships of body mass index (BMI) to obesity indices derived from anthropometry and to determine tracking of overweight between late childhood and early adolescence, in a cohort of children with mixed nutritional history. We also compared identification of overweight children using The International Obesity Task Force (IOTF) BMI cut-off points with skinfolds.

DESIGN

Prospective study.

SETTING

Kingston, Jamaica.

SUBJECTS

A total of 306 children examined at 7-8 y and at 11-12 y.

MEASUREMENTS

Triceps (TSF) and subscapular skinfolds (SSF), height and weight were measured. The sum of the skinfolds (sum SF), BMI, percentage body fat (%fat) and fat mass (FM) were calculated. Pubertal stage was assessed at 11-12 y.

RESULTS

Overweight increased from 3.5 to 9.5% over the follow-up period. BMI was better correlated with the other indices of adiposity in girls and in the older age group. BMI tracking over follow up was high. In regression analysis BMI explained 52 and 61% of the variance in FM in boys and girls at 7-8 y. This increased to 69% in both sexes at 11-12 y. Using the IOTF cut-off points BMI had low sensitivity to identify children >85th percentile of the NHANES references for SSF. The sensitivity for those assessed by TSF and sum SF was higher, but between 14 and 30% of the children were misclassified. The specificity of BMI was high.

CONCLUSIONS

Adiposity increased over follow-up. Although the cohort remained relatively lean BMI rank among the fattest children was maintained. Girls were fatter than boys, reflecting adult obesity patterns. Children identified as overweight by the IOTF BMI cut-off points are likely to have high body fatness. However the BMI cut-off points may not identify many children with high body fatness.

Cardiovascular risk factor profiles and their social gradient from adolescence to age 74 in a Swiss region

BACKGROUND

Few European studies have investigated how cardiovascular risk factors (CRF) in adults relate to those observed in younger generations.

OBJECTIVE

To explore this issue in a Swiss region using two population health surveys of 3636 adolescents ages 9-19 years and 3299 adults ages 25-74 years.

METHODS

Age patterns of continuous CRF were estimated by robust locally weighted regression and those of high-risk groups were calculated using adult criteria with appropriate adjustment for children.

RESULTS

Gender differences in height, weight, blood pressure, and HDL cholesterol observed in adults were found to emerge in adolescents. Overweight, affecting 10-12% of adolescents, was increasing steeply in young adults (three times among males and twice among females) in parallel with inactivity. Median age at smoking initiation was decreasing rapidly from 18 to 20 years in young adults to 15 in adolescents. A statistically significant social gradient in disfavor of the lower education level was observed for overweight in all age groups of women above 16 (odds ratios (ORs) 2.4 to 3.3, P < 0.01), for inactivity in adult males (ORs 1.6 to 2.0, P < 0.05), and for regular smoking in older adolescents (OR 1.9 for males, 2.7 for females, P < 0.005), but not for elevated blood pressure.

CONCLUSION

Discontinuities in the cross-sectional age patterns of CRF indicated the emergence of a social gradient and the need for preventive actions against the early adoption of persistent unhealthy behaviors, to which low-educated girls and women are particularly exposed.

Differences in pharmacokinetics between children and adults--II. Children's variability in drug elimination half-lives and in some parameters needed for physiologically-based pharmacokinetic modeling

In earlier work we assembled a database of classical pharmacokinetic parameters (e.g., elimination half-lives; volumes of distribution) in children and adults. These data were then analyzed to define mean differences between adults and children of various age groups. In this article, we first analyze the variability in half-life observations where individual data exist. The major findings are as follows. The age groups defined in the earlier analysis of arithmetic mean data (0-1 week premature; 0-1 week full term; 1 week to 2 months; 2-6 months; 6 months to 2 years; 2-12 years; and 12-18 years) are reasonable for depicting child/adult pharmacokinetic differences, but data for some of the earliest age groups are highly variable. The fraction of individual children's half-lives observed to exceed the adult mean half-life by more than the 3.2-fold uncertainty factor commonly attributed to interindividual pharmacokinetic variability is 27% (16/59) for the 0-1 week age group, and 19% (5/26) in the 1 week to 2 month age group, compared to 0/87 for all the other age groups combined between 2 months and 18 years. Children within specific age groups appear to differ from adults with respect to the amount of variability and the form of the distribution of half-lives across the population. The data indicate departure from simple unimodal distributions, particularly in the 1 week to 2 month age group, suggesting that key developmental steps affecting drug removal tend to occur in that period. Finally, in preparation for age-dependent physiologically-based pharmacokinetic modeling, nationally representative NHANES III data are analyzed for distributions of body size and fat content. The data from about age 3 to age 10 reveal important departures from simple unimodal distributional forms-in the direction suggesting a subpopulation of children that are markedly heavier than those in the major mode. For risk assessment modeling, this means that analysts will need to consider "mixed" distributions (e.g., two or more normal or log-normal modes) in which the proportions of children falling within the major versus highweight/fat modes in the mixture changes as a function of age. Biologically, the most natural interpretation of this is that these subpopulations represent children who have or have not yet received particular signals for change in growth pattern. These apparently distinct subpopulations would be expected to exhibit different disposition of xenobiotics, particularly those that are highly lipophilic and poorly metabolized.

Predicting overweight and obesity in adulthood from body mass index values in childhood and adolescence

BACKGROUND

The Centers for Disease Control and Prevention (CDC) introduced the clinical use of the body mass index (BMI; in kg/m(2)) in growth charts for young males and females.

OBJECTIVE

This study updates our previous report with the use of new CDC BMI charts and definitions of adult overweight and obesity to predict adult overweight or obesity.

DESIGN

Logistic models were fitted to relate adult overweight and obesity to childhood and adolescent BMI values at each age for 166 males and 181 females in the Fels Longitudinal Study and were applied to predict adult overweight and obesity at the 75th, 85th, and 95th percentiles on the CDC charts of childhood and adolescent BMI.

RESULTS

A child or adolescent with a high BMI percentile on the CDC BMI-for-age growth charts has a high risk of being overweight or obese at 35 y of age, and this risk increases with age. For example, the probability of adult obesity at the 85th percentile for young males was </=20% to 17 y of age and 20-59.9% afterward; the corresponding probability for young females was 20-39.9% to 18 y of age and 40-59.9% afterward.

CONCLUSION

Our clinically applicable method assigns a child's or adolescent's BMI value to a group with a known probability of overweight or obesity in adulthood.

Resting and reactive blood pressure. Predictors of ambulatory blood pressure in older adults with hypertension

The study examined whether reactive change scores from a short blood pressure (BP) reactivity protocol, resting BP, or resting pulse pressure (PP) would be predictors of 24-hour ambulatory BP and BP load in cardiac patients. The study used a single-group design, with both an experimental clinical component and an observational field component. Both components used repeated measurement methods. The study population consisted of 45 adult patients with a mean age of 64.6 +/- 8.5 years who were diagnosed with cardiac disease in a cardiac rehabilitation program and who were taking anti-hypertensive medication. Blood pressure reactivity was operationalized with a speech protocol. During the speech protocol, BP was measured with an automatic device (Dinamap) while patients talked about their health and about their usual day. Twenty-four-hour ambulatory BP measurement followed the speech protocol. Resting systolic BP and resting PP were significant predictors of 24-hour ambulatory systolic BP, and resting systolic BP was a significant predictor of systolic BP load. No predictors were significant of 24-hour diastolic BP or diastolic BP load. Initial resting BP and PP may be used in clinical settings to assess hypertension management. Future studies are necessary to confirm the ability of resting BP to predict ambulatory BP and BP load in older adults who are medicated and hypertensive.

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.

Dietary intakes among Croatian schoolchildren and adolescents

The aim of this study was to evaluate dietary intakes among 575 schoolchildren and adolescents in Croatia because of the lack of data. The completely quantified Food Frequency Questionnaire (FFQ) method was used to identify dietary intakes. Body weight, height and body fat were measured also. Daily energy intake was 95.5 and 83.3% RDA in children and adolescents respectively. Protein intake was very high in both children and adolescents (235.9 vs. 139.6% RDA). Children achieved RDAs for more micronutrients than adolescents did. Children had significantly higher cholesterol (263.7 vs. 231.3 mg) and dietary fiber intake (84.7 vs. 69.2% of the "age + 5" rule). Adolescents consumed significantly more fruit than children (324.8 vs. 204.2 g/day) did. Consumption of vegetables did not differ significantly (269.1 and 255.7 g/day in children and adolescents respectively). In more than 60% of children and adolescents, breakfast provided more than 30% of daily energy intake. Soft drinks and fast food consumption correlated in both children (r = 0.29; p < 0.01) and adolescents (r = 0.43; p < 0.001). No significant correlation was found between BMI and dietetic parameters. Percentage of body fat negatively correlated with fruit intake in children (r = -0.20; p < 0.05) and with intake of cereal products (r = -0.34; p < 0.001) and milk (r = -0.22; p < 0.05) in adolescents.

Medical management of obesity

Obesity has become a major health problem in many countries because of its high prevalence and causal relationship with serious medical complications. Many of the medical complications associated with obesity improve with intentional weight in a dose-dependent fashion, and even a modest weight loss of 50% of initial weight has beneficial effects. This article reviews the nonsurgical approaches for achieving weight loss in obese persons.

Childhood and adolescent obesity. Prevalence and significance

The prevalence of children and adolescents with body mass index (BMI) of greater than 95th percentile has doubled in the last 2 decades (present prevalence is 10.9%) and there is a 50% increase in the prevalence of those with a BMI greater than 85th percentile (present prevalence is 22.0%) in the US. There are substantial risks for morbidity in obese children even before they reach adulthood. Further, if obesity in childhood persists into the adult years, the morbidity and mortality is greater than if the obesity developed in the adult. Screening using appropriate historical and physical data will reveal those children most in need of modification of weight gain.

Childhood body composition in relation to body mass index

OBJECTIVE

The aim is to describe body composition in relation to body mass index (BMI; body weight/stature(2)) to provide health care professionals insight into the meaning, significance, and limitations of BMI as an index of adiposity during childhood.

METHODS

Data from 387 healthy, white children 8 to 18 years of age from the Fels Longitudinal Study were analyzed. Measurements were scheduled annually and each child was examined 1 to 11 times, totaling 1748 observations. Total body fat (TBF) and fat-free mass (FFM) were determined from hydrodensitometry. Stature and weight were measured using standard methods and BMI and the components of BMI, TBF/stature(2), and FFM/stature(2) were calculated. Analyses included correlations between BMI and body composition variables; age-related patterns of BMI, TBF/stature(2), and FFM/stature(2); and annual changes in BMI, TBF/stature(2), and FFM/stature(2).

RESULTS

Generally, correlations between BMI and body composition variables were strong and significantly different from zero. Means for BMI throughout childhood were similar for boys and girls, although significantly larger values were observed for girls at ages 12 to 13 years. Age-related patterns of TBF/stature(2) and FFM/stature(2) differed between sexes. In each sex, annual increases in BMI were driven primarily by increases in FFM/stature(2) until late adolescence, with increases in TBF/stature(2) contributing to a larger proportion of the BMI increases in girls than in boys.

CONCLUSIONS

Unlike adults, annual increases in BMI during childhood are generally attributed to the lean rather than to the fat component of BMI. Because the properties of BMI vary during childhood, health care professionals must consider factors such as age and sex when interpreting BMI.