Nicole L. Mihalopoulos

Trajectories of Fat Mass Index, Fat Free–Mass Index, and Waist Circumference in Children: Project HeartBeat!

BACKGROUND Body composition and fat distribution change dramatically during adolescence. Data based on longitudinal studies to describe these changes are limited. The aim of this study was to describe age-related changes in fat free-mass index (FFMI) and fat mass index (FMI), which are components of BMI, and waist circumference (WC) in participants of Project HeartBeat!, a longitudinal study of children. METHODS Anthropometric measurements and body composition data were obtained in a mixed longitudinal study of 678 children (49.1% female, 20.1% black), initially aged 8, 11, and 14 years, every 4 months for 4 years (1991-1995). Trajectories of change from ages 8 to 18 years were measured for FFMI, FMI, and WC. Because of the small number of observations for black participants, trajectories for this group were limited to ages 8.5-15 years. RESULTS Body mass index, FFMI, and WC increased steadily with age for all race-gender cohorts. However, in nonblack girls, FFMI remained constant after about age 16 years. For black boys and girls, FFMI was similar at age 8.5 years but increased more steeply for black boys by age 15 years. In girls, FMI showed an upward trend until shortly after age 14 years, when it remained constant. In boys, FMI increased between age 8 years and age 10 years, and then decreased. CONCLUSIONS The extent to which each component of BMI contributes to the changes in BMI depends on the gender, race, and age of the individual. Healthcare providers need to be aware that children who show upward deviation of BMI or BMI percentiles may have increases in their lean body mass rather than in adiposity.

Expected Changes in Clinical Measures of Adiposity During Puberty

BACKGROUND Clinicians use several measures to estimate adiposity. Body mass index (BMI), although not a measure of adiposity, is commonly used to define weight status. Percent body fat (%BF) measures total body fatness, which is composed of central and peripheral fat, estimated by waist circumference (WC) and skinfold thickness, respectively. Abnormal increases in fat during puberty may reflect an increased risk of developing cardiovascular disease. Therefore, it is important to establish the normal patterns of change in clinically relevant measures of adiposity. PURPOSE To describe the normal patterns of change in clinical measures of adiposity during puberty. DESIGN/METHODS Multilevel modeling and linear regression analyses of 642 children in Project HeartBeat!, aged 8-18 years (non-black and black), who had assessments of BMI, %BF, WC, sums of 2- and 6-skinfolds, and pubertal stage (PS) triennially between 1991 and 1995. RESULTS In males, the normal pattern from PS1 to PS5 is for %BF to decrease, skinfold thickness to remain stable, and WC to increase. However, after adjusting for height, WC does not change. In females, %BF remains stable from PS1 to PS5, whereas skinfold thickness increases. As in males waist-height ratio does not change, indicating that central adiposity does not normally increase during puberty. Although BMI increases in both genders and races from PS1 to PS5, mean values at PS5 were well below 25 kg/m(2). CONCLUSIONS During puberty, increase in %BF is abnormal in females and even more so in males. Likewise, increase in waist-height ratio is also abnormal and may suggest an increased risk for adiposity-associated morbidity.

Newborn Adiposity Measured by Plethysmography Is Not Predicted by Late Gestation Two-Dimensional Ultrasound Measures of Fetal Growth

Noninvasive measures of fetal and neonatal body composition may provide early identification of children at risk for obesity. Air displacement plethysmography provides a safe, precise measure of adiposity and has recently been validated in infants. Therefore, we explored relationships between term newborn percent body fat (%BF) measured by air displacement plethysmography to 2-dimensional ultrasound (2-D US) biometric measures of fetal growth and maternal and umbilical cord endocrine activity. A total of 47 mother/infant pairs were studied. Fetal biometrics by 2-D US and maternal blood samples were collected during late gestation (35 wk postmenstrual age); infants were measured within 72 h of birth. Fetal biometrics included biparietal diameter, femur length, head circumference, abdominal circumference (AC), and estimated fetal weight (EFW). Serum insulin, insulin-like growth factor (IGF) 1, IGF binding protein-3, and leptin concentrations were measured in umbilical cord and maternal serum. The mean %BF determined by plethysmography was 10.9 +/- 4.8%. EFW and fetal AC had the largest correlations with newborn %BF (R(2) = 0.14 and 0.10, respectively; P < 0.05); however, stepwise linear regression modeling did not identify any fetal biometric parameters as a significant predictor of newborn %BF. Newborn mid-thigh circumference (MTC; cm) and ponderal index (PI; weight, kg/length, cm(3)) explained 21.8 and 14.4% of the variability in %BF, respectively, and gave the best stepwise linear regression model (%BF = 0.446 MTC + 0.347 PI -29.692; P < 0.001). We conclude that fetal growth biometrics determined by 2-D US do not provide a reliable assessment of %BF in term infants.

Evaluation of AAP guidelines for cholesterol screening in youth: Project HeartBeat!

BACKGROUND The American Academy of Pediatrics (AAP) criterion for screening for hypercholesterolemia in children is family history of hypercholesterolemia or cardiovascular disease or BMI > or =85th percentile. This paper aims to determine the sensitivity, specificity, and positive predictive value (PPV) of dyslipidemia screening using AAP criteria along with either family history or BMI. METHODS Height, weight, plasma total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, and family history were obtained for 678 children aged 8, 11, and 14 years, enrolled from 1991 to 1993 in Project HeartBeat!. Sensitivity, specificity, and PPV screening of each lipid component using family history alone, BMI > or =85th percentile alone, or family history and/or BMI > or =85th percentile, were calculated using 2008 AAP criteria (total cholesterol, LDL-C, and triglycerides > or =90th percentile; HDL-C <10th percentile). RESULTS Sensitivity of detecting abnormal total cholesterol, LDL-C, HDL-C, and triglycerides using family history alone ranged from 38% to 43% and significantly increased to 54%-66% using family history and/or BMI. Specificity significantly decreased from approximately 65% to 52%, and there were no notable changes in PPV. In black children, cholesterol screening using the BMI > or =85th percentile criterion had higher sensitivity than when using the family history criterion. In nonblacks, family history and/or BMI > or =85th percentile had greater sensitivity than family history alone. CONCLUSIONS When the BMI screening criterion was used along with the family history criterion, sensitivity increased, specificity decreased, and PPV changed trivially for detection of dyslipidemia. Despite increased screening sensitivity by adding the BMI criterion, a clinically significant number of children still may be misclassified.

Evaluation of the Gold Medal Schools Program

Utahs Gold Medal Schools program supports the adoption of school policies that provide opportunities for nutritious food choices and regular physical activity. The effectiveness of Gold Medal Schools was evaluated via anthropometric measurements and dietary and physical activity surveys. The study population included first-, third-, and fifth-grade elementary school students and parents from four schools in Tooele County, UT. Two schools implemented Gold Medal Schools (intervention) and two did not (comparison). Data were collected at baseline (June 2005) and 1 year (May 2006). Body mass index (calculated as kg/m(2)) z scores increased significantly in the comparison group (0.53+/-0.38; P<0.05), but not in the intervention group (0.21+/-0.47; P=0.484), from baseline to 1 year. Children in the Gold Medal Schools cohort reported drinking fewer soft drinks per day (excluding diet drinks) at 1 year (P=0.008) and walking or biking to school more often at baseline and 1 year (P<0.001) than non-Gold Medal Schools children. While children in both groups increased the days per week they walked or biked to school, a substantial improvement was observed for the non-Gold Medal Schools students only (P<0.001). Overall, this pilot study suggests that Gold Medal Schools positively impacted body mass index z scores and health behaviors among elementary-aged students.

Changes in Fasting Lipids during Puberty.

OBJECTIVE To describe longitudinal changes in plasma lipid levels and pubertal stage in youths from age 8-18 years, in Project HeartBeat! STUDY DESIGN Fasting blood samples and pubertal stage, using physical assessment of secondary sex characteristics, were obtained every 4 months for up to 4 years in a mixed longitudinal study of 633 children (49.1% female, 20.1% black), initially aged 8, 11, and 14 years. Total cholesterol, low density lipoprotein-cholesterol, high density lipoprotein-cholesterol, triglycerides (TG), and nonhigh density lipoprotein-cholesterol measurements were obtained. Data were collected from 1991-1995. RESULTS Pubertal stage correlations with age varied among all race-sex groups (range, r = 0.61-0.70), and a given pubertal stage could represent a range of 5 years or more of chronological age. Throughout puberty, levels of total cholesterol, low density lipoprotein-cholesterol, and nonhigh density lipoprotein-cholesterol decreased, TG in males increased, and high density lipoprotein-cholesterol and TG in females showed no changes. Within a given pubertal stage, plasma lipid levels tended to differ by race, sex, or both. CONCLUSIONS Lipid levels change markedly by pubertal stage, and patterns differ by sex and race. Chronological age ranges widely within a given pubertal stage and is an insensitive indicator of pubertal stage and the related changes in lipid levels. Pubertal development should be considered when determining screening criteria to identify youths with adverse blood lipid levels.

Special population considerations and regulatory affairs for clinical research

Abstract Special populations, including women (non-pregnant and pregnant), pediatrics, and the elderly, require additional consideration with regard to clinical research. There are very specific regulatory laws, which protect these special populations, that need to be understood and adhered to in order to perform clinical research. This review provides a broad overview of some of the physiological differences in special populations and discusses how these differences may affect study design and regulatory considerations. These various special populations, with respect to regulatory affairs, are clearly defined within the Code of Federal Regulations. The definition of “special population” exists to provide enhanced awareness of their vulnerabilities, thereby allowing the creation of regulatory guidance aimed to decrease injury or outright harm. Currently, progress is being made to be more inclusive of special populations in clinical trials. This reflects changing attitudes towards drug information, with it being more representative of those patients that will ultimately be prescribed or exposed to the therapy. However, all research undertaken in these populations should be performed in a manner that ensures all protections of each participant are upheld.

Physicians and Physician Trainees Rarely Identify or Address Overweight/Obesity in Hospitalized Children

OBJECTIVES To determine how frequently physicians identify and address overweight/obesity in hospitalized children and to compare physician documentation across training level (medical student, intern, resident, attending). STUDY DESIGN We conducted a retrospective chart review. Using an administrative database, Centers for Disease Control and Prevention body mass index calculator, and random sampling technique, we identified a study population of 300 children aged 2-18 years with overweight/obesity hospitalized on the general medical service of a tertiary care pediatric hospital. We reviewed admission, progress, and discharge notes to determine how frequently physicians and physician trainees identified (documented in history, physical exam, or assessment) and addressed (documented in hospital or discharge plan) overweight/obesity. RESULTS Physicians and physician trainees identified overweight/obesity in 8.3% (n = 25) and addressed it in 4% (n = 12) of 300 hospitalized children with overweight/obesity. Interns were most likely to document overweight/obesity in history (8.3% of the 266 patients they followed). Attendings were most likely to document overweight/obesity in physical examination (8.3%), assessment (4%), and plan (4%) of the 300 patients they followed. Medical students were least likely to document overweight/obesity including it in the assessment (0.4%) and plan (0.4%) of the 244 hospitalized children with overweight/obesity they followed. CONCLUSIONS Physicians and physician trainees rarely identify or address overweight/obesity in hospitalized children. This represents a missed opportunity for both patient care and physician trainee education.

Validity and reliability of perinatal biomarkers of adiposity after storage as dried blood spots on paper

To validate use of chip‐based immunoaffinity capillary electrophoresis on dried blood spot samples (DBSS) to measure obesity‐related hormones.

Reframing the View of Women's Health in the United States: Ideas from a Multidisciplinary National Center of Excellence in Women's Health Demonstration Project

Caren J Frost1*, Patricia A Murphy2, Janet M Shaw3, Kirtly P Jones4, Michael Varner4, Nicole Mihalopoulos5, Erica Lake6, Sally Patrick6, Leanne Johnston4 and Kathleen B Digre7 1College of Social Work, University of Utah, USA 2College of Nursing, University of Utah, USA 3College of Health, University of Utah, USA 4Department of Obstetrics and Gynecology, University of Utah, USA 5Pediatrics Adolescent Medicine, University of Utah, USA 6Spencer S. Eccles Health Sciences Library, University of Utah, USA 7Department of Neurology, University of Utah, USA