Kristine C. Jordan

IGF-1 and IGF-Binding Proteins and Bone Mass, Geometry, and Strength: Relation to Metabolic Control in Adolescent Girls With Type 1 Diabetes

Children and adolescents with poorly controlled type 1 diabetes mellitus (T1DM) are at risk for decreased bone mass. Growth hormone (GH) and its mediator, IGF‐1, promote skeletal growth. Recent observations have suggested that children and adolescents with T1DM are at risk for decreased bone mineral acquisition. We examined the relationships between metabolic control, IGF‐1 and its binding proteins (IGFBP‐1, ‐3, ‐5), and bone mass in T1DM in adolescent girls 12–15 yr of age with T1DM (n = 11) and matched controls (n = 10). Subjects were admitted overnight and given a standardized diet. Periodic blood samples were obtained, and bone measurements were performed. Serum GH, IGFBP‐1 and ‐5, glycosylated hemoglobin (HbA1c), glucose, and urine magnesium levels were higher and IGF‐1 values were lower in T1DM compared with controls (p < 0.05). Whole body BMC/bone area (BA), femoral neck areal BMD (aBMD) and bone mineral apparent density (BMAD), and tibia cortical BMC were lower in T1DM (p < 0.05). Poor diabetes control predicted lower IGF‐1 (r2 = 0.21) and greater IGFBP‐1 (r2 = 0.39), IGFBP‐5 (r2 = 0.38), and bone‐specific alkaline phosphatase (BALP; r2 = 0.41, p < 0.05). Higher urine magnesium excretion predicted an overall shorter, lighter skeleton, and lower tibia cortical bone size, mineral, and density (r2 = 0.44–0.75, p < 0.05). In the T1DM cohort, earlier age at diagnosis was predictive of lower IGF‐1, higher urine magnesium excretion, and lighter, thinner cortical bone (r2 ⩽ 0.45, p < 0.01). We conclude that poor metabolic control alters the GH/IGF‐1 axis, whereas greater urine magnesium excretion may reflect subtle changes in renal function and/or glucosuria leading to altered bone size and density in adolescent girls with T1DM.

A nutrition and physical activity intervention promotes weight loss and enhances diet attitudes in low-income mothers of young children.

The purpose of this study was to evaluate a nutrition and physical activity program for reducing body weight and improving nutrition attitudes in mothers of young children. A convenience sample of 114 intervention mothers and 33 comparison mothers was recruited from public health clinics and community centers. Eligibility criteria included Hispanic, African American, or white ethnicity; body mass index of at least 25 kg/m(2); low income (< 200% of the federal poverty index); and youngest child aged 1 to 4 years. For intervention participants, height, weight, percentage of body fat, waist circumference, demographics, nutrition attitudes, and dietary intake were measured at weeks 0 and 8; height, weight, percentage of body fat, and waist circumference were reassessed at 6 months. Overweight mothers in the comparison group provided anthropometric and demographic data at weeks 0 and 8. Changes in anthropometrics, attitudes, and dietary intake were evaluated in intervention mothers. Anthropometric data of intervention vs comparison group mothers were examined. Differences in anthropometrics and attitude scores between weight loss responders (> or = 2.27 kg) and nonresponders (< 2.27 kg) were assessed at week 8. Intervention participants lost weight (x = -2.7 kg; P < .001), whereas comparison mothers gained a slight amount of weight (x = 0.1 kg) by week 8. Weight loss responders had healthier eating attitudes (5.6 vs 5.2; P < .01) and fewer perceived barriers (2.4 vs 2.9; P < .05) than nonresponders postintervention. In conclusion, this dietary and physical activity curriculum is a valuable resource for weight management programs serving low-income women.

Effecting Healthy Lifestyle Changes in Overweight and Obese Young Adults With Intellectual Disability

We evaluated a 12-week recreation center-based healthy lifestyle intervention for 30 obese home-dwelling young adults (YA) with intellectual disabilities. Three cohorts participated: YA only, YA and parents, and parents only. The YA cohorts received a nutrition/exercise intervention; parents focused on modeling healthy lifestyle behaviors. Outcomes included YA blood, nutrition, anthropometric, and fitness measures at pre, post, and 3-month follow-up. Compared with wait-list controls, the YA-only cohort improved immediately postintervention in blood pressure (BP), weight, and balance (p < .05). At 3-month follow-up, no intervention was consistently superior; overall reductions in weight, BP, hip circumference, and exercise barriers were obtained (p < .05). Linear and curvilinear changes from baseline to 3 months after the intervention varied by outcome and participant. Participants with Down syndrome lost less weight.

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.

Short-term weight loss in overweight/obese low-income women improves plasma zinc and metabolic syndrome risk factors.

Metabolic syndrome is a group of disorders involving obesity, insulin resistance, dyslipidemia and hypertension. Obesity is the most crucial risk factor of metabolic syndrome, because it is known to precede other risk factors. Obesity is also associated with disturbances in the metabolism of the trace mineral, zinc. The overall purpose of this study was to investigate the effects of short-term weight loss on plasma zinc and metabolic syndrome risk factors. An 8-week weight loss intervention study was conducted with 90 low-income overweight/obese mothers, whose youngest child was 1-3 years old. Plasma levels of zinc, glucose, insulin, leptin, triglycerides, total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol were measured and compared at weeks 0 and 8 of the weight loss program. At pre-study, plasma zinc was low in 39% and, within normal values in 46%, of obese/overweight mothers. By the end of intervention, plasma zinc rose by 22% and only 5% of the mothers continued to exhibit low plasma zinc. At post-study, the metabolic syndrome risk factors of waist circumference, HDL cholesterol, and diastolic blood pressure (p<0.05) showed significant improvements. Plasma zinc increased by a greater margin (67%) in women with low zinc, as compared to those with normal zinc (18%); weight reduction was similar in both the groups. Finally, changes in % body fat were related negatively with changes in plasma zinc (r=- 0.28, p<0.05). The circulating levels of zinc, as well as the metabolic syndrome components, showed significant improvements in overweight/obese low-income women after weight loss.

Mid-arm circumference is a reliable method to estimate adiposity in preterm and term infants

Background:Premature birth is associated with increased adipose deposition after birth. Standard anthropometry (body weight, length, and head circumference) may not adequately assess fat deposition. Validated methods to assess adiposity are needed to optimize growth quality in preterm infants. The purpose of this study was to identify covariates of infant body fat.Methods:Air displacement plethysmography (ADP), standard anthropometry, and body circumferences were measured at hospital discharge in preterm (n = 28; 31–35 wk postmenstrual age (PMA)) and term (n = 28; 38–41 wks PMA) infants.Results:Body weight, length, and head circumference were lower for preterm infants (P < 0.05) at hospital discharge compared with that of term infants. Despite smaller body size and younger PMA, preterm infant percent body fat (%BF) by ADP was 12.33 ± 4.15% vs. 9.64 ± 4.01% in term infants (P = 0.01). Mid-arm circumference (MAC) is a covariate of %BF in both preterm and term infants (adjusted R2 = 0.49; P < 0.001). In preterm infants alone, MAC accounted for 60.4% of the variability of percent body fat (%BF) by ADP (P < 0.01).Conclusions:Preterm infants have increased body fat deposition as they approach term-corrected age, and MAC is a reliable, low-cost measure for monitoring infant body fat deposition in preterm and term infants.

Vitamin D Intake Is Inadequate in Spinal Muscular Atrophy Type I Cohort Correlations With Bone Health

Children with type I spinal muscular atrophy commonly demonstrate reduced bone mineral density. Our objectives were to evaluate and assess adequacy of vitamin D intake, serum levels, and association with bone mineral density. Assessments were completed using 3-day food records and dual energy x-ray absorptiometry scans. The spinal muscular atrophy type I cohort included 22 males and 18 females (N = 40), with a mean age of 18.6 months. Data collection occurred from 2001 to 2011. Seventy-five percent of patients had inadequate intake of vitamin D at the initial visit. Using mixed-effects analyses, vitamin D and calcium intakes correlated positively with bone mineral density (r = 0.31 and r = 0.53, respectively). Increased vitamin D and calcium consumption were associated with an increase in bone mineral density (P = .04 and P = .01, respectively). Vitamin D intake correlated positively with serum levels (r = 0.65). Further study is needed to determine optimal intakes of vitamin D and calcium in the spinal muscular atrophy type I population.

Feasibility of community food item collection for the National Children's Study.

BACKGROUND The National Childrens Study proposes to investigate biological, chemical, physical, and psychosocial environmental exposures and their role on health outcomes in pregnant women and children. One specific area of concern is contaminant exposure through the ingestion of solid foods. National food contaminant databases may miss dietary exposures unique to specific communities and sources of food. OBJECTIVE The purpose of this study was to evaluate the feasibility of community food item collection for the assessment of pesticide exposure in pregnant women and young children. METHODS A prospective observational design was used to test the food collection protocol in mothers (n=45) of children aged 15-24 months in Salt Lake City, Utah. Foods for collection were based on: 1) frequency of different foods consumed by the target population as determined by the National Health and Nutrition Examination Survey data; 2) child food frequency questionnaire; and 3) likelihood of pesticide contamination in the foods. Assessment measures included: demographics, environmental health survey, quality assurance checklist, and participant evaluation form. RESULTS An average of three food items were obtained from 44 households, yielding a collection rate of 97.8%. Overall, 100% of the food samples were rated as acceptable. Moreover, a vast majority of mothers reported that the study was not burdensome (95.5%) and that preparing the food sample was easy (93.2%). CONCLUSIONS This study suggests that the community food item collection methodology shows promise as a low-burden approach for capturing dietary exposures on a household level, and appears to be a feasible tool for large population studies to assess dietary exposures unique to specific communities.

Breast-feeding, Leptin: Adiponectin Ratio, and Metabolic Dysfunction in Adolescents with Obesity

Objectives Increased adiposity increases leptin and decreases adiponectin concentrations, resulting in an increased leptin:adiponectin ratio (LAR). In adults, components of the metabolic syndrome and other cardiometabolic risk factors, what we classify here as “metabolic dysfunction,” are associated with both a high LAR and a history of being breast-fed. The relation among breast-feeding, LAR, and degree of metabolic dysfunction in obese youth is unknown. The purpose of our pilot study was to explore this relation and estimate the effect size of the relations to determine the sample size needed to power future prospective studies. Methods We obtained fasting levels of leptin, adiponectin, lipids, insulin, and glucose from obese youth (aged 8–17 years). Weight, height, waist circumference, blood pressure, and breast-feeding history also were assessed. Results Of 96 participants, 78 were breast-fed as infants, 54% of whom were breast-fed for >6 months. Wide variation was observed in LARs among children who were and were not breast-fed (>100% coefficient of variation). Overall, prevalence of metabolic dysfunction in the cohort was 94% and was not proven to be associated with higher LAR. Conclusions In this cohort of obese youth, we found a high prevalence of breast-feeding, metabolic dysfunction, and wide variation in the LARs. Based on the effect size estimated, future studies would need to enroll >1500 patients or identify, stratify, and selectively enroll obese patients without metabolic dysfunction to accurately determine whether breast-feeding in infancy influences LARs or metabolic dysfunction among obese youth.