Faculty Bibliography

Adolescent obesity continues to be a major public health issue with a third of American adolescents being overweight or obese. Excess weight is associated with cardiovascular risk factors and pre-diabetes. High school students identified as carrying excess weight [body mass index (BMI) >/=25 kg/m2, or BMI percentile >/=85 %] were invited to participate in The BODY Project, an intervention that included a medical evaluation and a personalized medical report of the results of that evaluation sent to the parent/guardian at home. The medical evaluation and report was repeated 12 months later. The reports also contained advice on how the individual student could modify their lifestyle to improve the specific medical parameters showing abnormalities. Outcomes were change in BMI, blood pressure, high-density lipoprotein (HDL), low-density lipoprotein (LDL), fasting glucose, and fasting insulin. Students participating in The BODY Project intervention demonstrated modest, yet significant, reductions in BMI (p < 0.001) 1 year later, and also had significant improvements in systolic blood pressure (p < 0.001) and cholesterol profile (HDL p = 0.002; LDL p < 0.001) at follow-up. The BODY Project, by means of a minimal educational program anchored on the principle of teachable moments around the students' increased perception of their own risk for disease from the medical abnormalities uncovered, demonstrates evidence of potential effectiveness in addressing adolescent obesity.

Background. Increased prevalence of type 2 diabetes mellitus (T2DM) makes it important for pediatricians to use effective screening tools for risk assessment of prediabetes/T2DM in children. Methods. Children (n = 149) who had an oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) were studied. American Diabetes Association recommended screening criteria-HbA1c >/=5.7% and fasting plasma glucose (FPG) >/=100 mg/dL-were compared against OGTT. The homeostatic model assessment of insulin resistance (HOMA-IR), a mathematical index derived from fasting insulin and glucose, was compared with OGTT. We studied whether combining screening tests (HbA1c and fasting glucose or HbA1c and HOMA-IR) improved accuracy of prediction of the OGTT. Results. HbA1c of >/=5.7% had a sensitivity of 75% and specificity of 57% when compared with the OGTT. Combining screening tests (HbA1c >/=5.7% and FPG >/=100 mg/dL; HbA1c >/=5.7% and HOMA-IR >/=3.4) resulted in improved sensitivity (95.5% for each), with the HbA1c-FPG doing better than the HbA1c-HOMA-IR combination in terms of ability to rule out prediabetes (likelihood ratio [LR]) negative. 0.07 vs 0.14). Conclusions. HbA1c of >/=5.7% provided fair discrimination of glucose tolerance compared with the OGTT. The combination of HbA1c and FPG is a useful method for identifying children who require an OGTT.

AIM: To establish whether young children watched foreground electronic media or background media that was not aimed at them or was inappropriate for their age. METHODS: We performed a longitudinal analysis of mother-infant dyads participating in a larger parenting study. The primary dependent variable was maternal reports of watching habits from media diaries at 6, 14, 24 and 36 months. Independent variables were child age, programme content and whether the programme was turned on specifically for the child. RESULTS: We analysed 3570 programme exposures in 527 children, mostly from television. Children were significantly more likely to actually watch programmes if they were older, if the content was coded as 'educational young child' or if the parent tuned on the programme specifically so the child could watch it. Children under the age of two were more likely than older children to watch background media that featured age-inappropriate content or had not been turned on for them to watch [30% versus 16% of programmes; AOR = 2.19 (95%CI 1.82-2.65)]. CONCLUSION: Young children under the age of two frequently watch background media that has age-inappropriate content or has not been turned on for them to watch.

Abstract Background: Although disparities in child obesity exist during infancy, the underlying mechanisms are unclear. Assessing dissimilarities in feeding practices, styles, and beliefs may provide a better understanding of these mechanisms. This study sought to identify modifiable maternal-infant feeding behaviors that may contribute to disparities in early child obesity. Methods: This study is a cross-sectional analysis comparing mothers with infants (2 weeks to 6 months old) in a low-risk group of high-income white mothers to a high-risk group of low-income Hispanic mothers. Regression analysis was used to explore relationships between each group and (1) infant feeding practices, including breastfeeding, giving juice, and adding cereal to bottles, (2) controlling feeding styles, (3) beliefs about infant hunger and satiety, and (4) infant weight status. Results: The sample included 412 mothers (low-risk group, n=208; high-risk group, n=204). The high-risk group was less likely to exclusively breastfeed (adjusted odds ratio [AOR], 0.43; 95% confidence interval [CI], 0.22-0.83), more likely to introduce juice (AOR, 12.25; 95% CI, 3.44-43.62), and add cereal to the bottle (AOR, 10.61; 95% CI, 2.74-41.0). The high-risk group exhibited greater restrictive and pressuring feeding styles and was more likely to believe that mothers can recognize infant hunger and satiety and less likely to believe that infants know their own hunger and satiety. High-risk infants were more likely to have a weight-for-length percentile >85th percentile (AOR, 2.66; 95% CI, 1.10-6.45). Conclusions: Differences in infant feeding behaviors may contribute to disparities in early child obesity. Longitudinal studies are needed to determine the effect of these differences on child obesity.

Glucose obtained from unprocessed blood samples can decrease by 5%-7% per hour due to glycolysis. This study compared the impact of glucose degradation on measured glucose values by examining two different collection methods. For the first method, blood samples were collected in tubes containing sodium fluoride (NaF), a glycolysis inhibitor. For the second method, blood samples were collected in tubes containing a clot activator and serum gel separator and were centrifuged to separate the serum and plasma 20 minutes after sample collection. The samples used in the two methods were collected during the same blood draw and were assayed by the clinical laboratory 2-4 hours after the samples were obtained. A total of 256 pairs of samples were analyzed. The average glucose reading for the centrifuged tubes was significantly higher than the NaF tubes by 0.196 +/- 0.159 mmol/L (P < 0.01) or 4.2%. This study demonstrates the important role collection methods play in accurately assessing glucose levels of blood samples collected in the field, where working environment may be suboptimal. Therefore, blood samples collected in the field should be promptly centrifuged before being transported to clinical labs to ensure accurate glucose level measurements.

OBJECTIVES: To determine the point prevalences of metabolic syndrome (MetS) and its components among healthy weight, overweight, and obese inner-city public high school students, to compare the prevalences of MetS when using 2 different definitions (one with the impaired fasting glucose [IFG] level and the other with a homeostasis model assessment of insulin resistance [HOMA-IR] of 3.99 or higher to define the glucose regulation component), and to compare the degree to which HOMA-IR and fasting glucose level are associated with the other MetS components. DESIGN: Cross-sectional analysis. SETTING: Two New York City public high schools, from April 2008 through August 2011. PARTICIPANTS: Convenience sample of 1185 high school youth, comprising predominantly Hispanic and African American students from low-income households, participating in The Banishing Obesity and Diabetes in Youth Project, a medical screening and education program. MAIN OUTCOME MEASURES: Prevalences of the following individual MetS components: IFG threshold, HOMA-IR, hypertension, central adiposity, hypertriglyceridemia, and low high-density lipoprotein cholesterol. Rates of MetSIFG and MetSHOMA-IR were also assessed. RESULTS: MetSIFG and MetSHOMA-IR point prevalences were both 0.3% in the healthy weight group; they were 2.6% and 5.9%, respectively, in the overweight group and were 22.9% and 35.1%, respectively, in the obese group (P < .05 for both). An IFG threshold of 100 mg/dL or higher was found in 1.0% of participants, whereas a HOMA-IR of 3.99 or higher was found in 19.5% of participants. CONCLUSIONS: An elevated HOMA-IR is much more sensitive than an IFG threshold in identifying adolescents with metabolic dysregulation. Using a HOMA-IR threshold of 3.99 identifies more youth with MetS than using an IFG threshold of 100 mg/dL. In addition to increasing the sensitivity of MetS detection, HOMA-IR has a much higher association with the other MetS components than the IFG threshold and may better reflect a unified underlying pathologic process useful to identify youth at risk for disease.