Stephenie Wallace

Fibroblast growth factor‐21, body composition, and insulin resistance in pre‐pubertal and early pubertal males and females

Accumulating evidence derived primarily from animal models suggests that fibroblast growth factor‐21 (FGF‐21) may affect the musculoskeletal system via effects on the capacity of tissues to respond to insulin. A proportion of musculoskeletal properties and underpinnings of promoting/preventing insulin resistance are established early in the pubertal transition. Thus, the objective of this study was to test the hypothesis that insulin resistance and/or obesity will promote greater FGF‐21 concentration which will be inversely associated with musculoskeletal parameters [lean mass and bone mineral content (BMC)] in pre‐/early pubertal children. Given the sexual dimorphic nature of musculoskeletal development of fat mass accrual, differences by obesity status and sex were also investigated.

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

Objective: Obesity prevalence among African American (AA) girls is higher than that in other groups. Because typical energy-restriction obesity treatment strategies have had limited success, alterations in macronutrient composition may effectively improve metabolic outcomes in this population and affect future body composition trajectories. The objective was to evaluate the efficacy of a moderately restricted carbohydrate (CHO) versus a standard CHO diet on weight/fat loss and metabolic parameters in overweight/obese AA girls ages 9 to 14 years. Methods: A total of 26 AA girls (ranging from 92nd body mass index percentile and above) were assigned to either a reduced- (SPEC: 42% energy from CHO, n = 12) or a standard- (STAN: 55% of energy from CHO, n = 14) CHO diet (protein held constant) for 16 weeks. All of the meals were provided and clinically tailored to meet the estimated energy requirements (resting energy expenditure × 1.2 in eucaloric phase and resting energy expenditure × 1.2 − 1000 kcal in energy deficit phase). The first 5 weeks encompassed a eucaloric phase evaluating metabolic changes in the absence of weight change. The subsequent 11 weeks were hypocaloric (1000 kcal/day deficit) to promote weight/fat loss. Meal tests were performed during the eucaloric phase for metabolic analyses. Dual-energy x-ray absorptiometry was used to evaluate body composition. Results: Both groups experienced reductions in weight/adiposity, but the difference did not reach significance. The solid meal test indicated improved glucose/insulin homeostasis on the SPEC diet up to 3 hours postingestion. In addition, significantly lower triglycerides (P < 0.001) were observed on the SPEC diet. Conclusions: Dietary CHO reduction favorably influences metabolic parameters but did not result in greater weight/fat loss relative to a standard diet in obese AA girls. Future research is needed to determine long-term effectiveness of a reduced CHO diet on glucose and insulin homeostasis and how it may apply to weight maintenance/fat loss during development alone and/or in combination with additional weight loss/metabolic improvement strategies.

The Role of European Genetic Admixture in the Etiology of the Insulin Resistance Syndrome in Children: Are the Effects Mediated by Fat Accumulation?

OBJECTIVES To evaluate the contribution of European genetic admixture (EUADM) to insulin resistance syndrome (IRS) in a multiethnic sample of children age 7-12 years, and to explore whether body fat affects this relationship. STUDY DESIGN Anthropometric measurements and blood pressure were assessed in 243 children. After an overnight fast, an intravenous glucose tolerance test was conducted, and measures of fasting insulin/glucose, lipids, insulin sensitivity (SI), and acute insulin response to glucose (AIRg) were obtained. The proportion of EUADM was determined by maximum likelihood estimation using 140 ancestry informative markers. Subjects were stratified into tertiles according to the proportion of EUADM for analyses. Subjects were categorized as lean or obese using body fat percentage cutpoints (25% in boys, 30% in girls). RESULTS Among lean subjects (72%), the tertile representing the greatest proportion of EUADM was associated with higher SI (P<.001) and serum glucose (P<.05) and lower insulin (P<.05), AIRg (P<.001), high-density lipoprotein cholesterol (P=.05), and blood pressure (P<.05). However, among obese subjects, EUADM was associated only with SI (P<.05). CONCLUSIONS Our results suggest that population differences in IRS likely have a genetic component, but that the influence of genetic background may be masked by obesity.

Overcoming Challenges to Care in the Juvenile Justice System: A Case Study and Commentary

Youth in the criminal justice system commonly suffer from multiple medical and psychological health problems. Because they likely live in lower socioeconomic environments, the medical care they receive through the justice system might be their only recent medical care and can result in the discovery of health problems or chronic illnesses that must be managed while in the system and beyond. We describe the case of an adolescent diagnosed with a serious chronic disease during his time in an urban detention center to illustrate how health workers and justice staff must use a team approach in caring for this vulnerable population of children. Barriers to appropriate care, including social and systems-level challenges, are discussed. The lessons learned in this case can be applied more broadly to other vulnerable youth populations, including those in foster care and impoverished communities where the primary care pediatrician (or other assigned pediatric specialist) is both the leader of the medical team and an advocate for quality care.

Can Reduction in Dietary Carbohydrate Play a Role in Normalizing the Endocrine-Metabolic State Perturbed During the Pubertal Transition? The PRIMO Pilot Study

Macronutrient modification may play a role in normalizing the endocrine-metabolic state characteristically perturbed during the pubertal transition. This study evaluated the effect of a reduced carbohydrate (redCHO) diet relative to a standard (STAN) diet on the reproductive hormonal milieu and insulin dynamics in obese African American (AA) girls during the pubertal transition. The authors hypothesized that a 5-week eucaloric, redCHO diet would decrease fasting insulin and estradiol (thereby altering follicle stimulating hormone [FSH] and sex-hormone-binding globulin [SHBG] concentration) and improve insulin sensitivity, relative to a STAN diet. Participants were assigned to 1 of 2 diets: redCHO (43% carbohydrate) or STAN (55% carbohydrate) for 5 weeks. All food was provided with energy needs determined by resting energy expenditure multiplied by a 1.2 activity factor. This relatively short, redCHO dietary intervention affected reproductive hormonal concentrations but not insulin dynamics. An inverse rel...

149 ADOLESCENT WEIGHT PERCEPTIONS, CONCERNS, AND MANAGEMENT PRACTICES.

Background Adolescents at risk for overweight, who would benefit from long-term lifestyle changes, may resist weight management counseling if they consider their weight to be healthy or are not concerned about their weight. The purpose of this study was to examine the self-perceptions and concerns of adolescents related to their weight and weight management. Methods We surveyed 100 adolescent health-fair participants, 14-19 years old, in an urban minority community. This sample was primarily African American (95%) and female (74%). Participants completed a one-page survey consisting of questions about height, weight, family history of obesity-related conditions, self-description of their weight, and methods to manage their weight. Results Calculated from self-reported heights and weights, 40% of the adolescents had a body mass index (BMI)

255 LEVEL OF PHYSICAL ACTIVITY, DIETARY HABITS AND BODY MASS INDEX IN RURAL YOUTH PARTICIPATING IN 2003 NATIONAL YOUTH SPORTS PROGRAM

85thpercentile for age, gender, and height, though only 27% of the population described themselves as overweight. Diabetes (58%) and hypertension (62%) were the most prevalent conditions reported by family history. The most popular methods for weight management were increasing physical activity (58%) and eating more fruits and vegetables (55%). Although 58% of the youth considered themselves to have a healthy weight, the 70% of the sample were trying to do something about their weight. Adolescents in the overweight category (BMI

198. Teen Driving Anticipatory Guidance

85th percentile), as compared to those in the normal weight category, were more likely to report a family history of high cholesterol (p = .029), described themselves as overweight (p = .001), described their weight as unhealthy (p = .034), were concerned about their weight (p = .015), were trying to do something about their weight (p = .0001), and used eating less sweets as a method of weight control (p = .01). Conclusions Our findings suggest that overweight and normal weight youth are concerned about their weight and using weight management strategies, although those at risk for overweight do not perceive themselves to have this risk. Health care professionals can educate youth about their personal health risks related to overweight, encourage already existing healthful weight management methods, and point adolescents toward other healthy lifestyle changes in counseling adolescents regarding weight management practices.

Low HDL cholesterol may lead to disruption of bone (re)modeling in obese early pubertal girls

Purpose To determine the prevalence of youth who have a body mass index (BMI) ≥ 85th percentile and related characteristics (elevated blood pressures, dietary and physical habits) among rural participants. Methods Cross-sectional assessment of adolescents (ages 10 to 14 years) participating in the 2003 National Youth Sports Program (NYSP) in a rural southeastern US city was done. Heights, weights, and blood pressures were collected during pre-participation examinations. BMIs and percentiles were calculated based on gender standards. During the first week of the 2003 NYSP, a questionnaire regarding dietary habits and physical activities was administrated. Descriptive and bivariate analyses were performed using SPSS software. Results 236 youth (mean age 11.9 years) had pre-participation examinations; 8 were excluded for invalid variables, resulting in 228 analyzable participants. The mean BMI percentile was at the 70th (range 1-99th). 42% (N = 99) of the youth had a BMI ≥ 85th percentile for their age and gender. Having an elevated systolic or diastolic blood pressure (greater than 90th percentile for height and gender) was significantly associated with having a BMI ≥ 85th percentile (p = .015 and p = .022 respectively). Of those who received medical assessments, 124 youth had completed questionnaires. 85% of respondents reported both eating less than 4 fruits and vegetables per day; 78% had 2 or more sodas per day, and 50% drank milk one time or less per day. Fast food was eaten more than twice per week by 81% of participants and 59% visited the convenience store more than twice per week for snacks. 61% stated that they ate breakfast five times or less per week. From the questions regarding physical activity, 78% and 57% of youth respectively watched TV or played computer/video games more than 3 hours per day. 68% stated that there was not a park near their house, with 71% stating that they did not feel safe getting physical activity at a park. Nearly half (48%) did not participate in a sport team after school. No significant associations between having a BMI ≥ 85th percentile and these dietary or physical activity habits were found. Conclusions The study demonstrated the need for interventions to promote healthy eating and physical activities in rural NYSP participants. Programs targeting obesity prevention and intervention as well as blood pressure control are feasible in this setting. The NYSP, often implemented through venues at historically black universities/colleges, is attended by over 50,000 disadvantaged youth annually.