Correlations among adiposity measures in school-aged children

BACKGROUND: Given that it is not feasible to use dual x-ray absorptiometry (DXA) or other reference methods to measure adiposity in all pediatric clinical and research settings, it is important to identify reasonable alternatives. Therefore, we sought to determine the extent to which other adiposity measures were correlated with DXA fat mass in school-aged children. METHODS: In 1110 children aged 6.5-10.9 years in the pre-birth cohort Project Viva, we calculated Spearman correlation coefficients between DXA (n=875) and other adiposity measures including body mass index (BMI), skinfold thickness, circumferences, and bioimpedance. We also computed correlations between lean body mass measures. RESULTS: 50.0% of the children were female and 36.5% were non-white. Mean (SD) BMI was 17.2 (3.1) and total fat mass by DXA was 7.5 (3.9) kg. DXA total fat mass was highly correlated with BMI (r(s)=0.83), bioimpedance total fat (r(s)=0.87), and sum of skinfolds (r(s)=0.90), and DXA trunk fat was highly correlated with waist circumference (r(s)=0.79). Correlations of BMI with other adiposity indices were high, e.g., with waist circumference (r(s)=0.86) and sum of subscapular plus triceps skinfolds (r(s)=0.79). DXA fat-free mass and bioimpedance fat-free mass were highly correlated (r(s)=0.94). CONCLUSIONS: In school-aged children, BMI, sum of skinfolds, and other adiposity measures were strongly correlated with DXA fat mass. Although these measurement methods have limitations, BMI and skinfolds are adequate surrogate measures of relative adiposity in children when DXA is not practical

The Influence of Antenatal Partner Support on Pregnancy Outcomes

BACKGROUND: While there has been considerable attention given to the multitude of maternal factors that contribute to perinatal conditions and poor birth outcomes, few studies have aimed to understand the impact of fathers or partners. We examined associations of antenatal partner support with psychological variables, smoking behavior, and pregnancy outcomes in two socioeconomically distinct prebirth cohorts. MATERIALS AND METHODS: Data were from 1764 women recruited from an urban-suburban group practice (Project Viva) and 877 women from urban community health centers (Project ACCESS), both in the Boston area. Antenatal partner support was assessed by the Turner Support Scale. Multivariable linear and logistic regression analyses determined the impact of low antenatal partner support on the outcomes of interest. RESULTS: In early pregnancy, 6.4% of Viva and 23.0% of ACCESS participants reported low partner support. After adjustment, low partner support was cross-sectionally associated with high pregnancy-related anxiety in both cohorts (Viva AOR 1.8; 95% CI: 1.0-3.4 and ACCESS AOR 1.9; 95% CI: 1.1-3.3) and with depression in ACCESS (AOR 1.9; 95% CI: 1.1-3.3). In Viva, low partner support was also related to depression mid-pregnancy (AOR 3.1; 95% CI: 1.7-5.7) and to smoking (AOR 2.2; 95% CI: 1.3-3.8). Birth weight, gestational age, and fetal growth were not associated with partner support. CONCLUSIONS: This study of two economically and ethnically distinct cohorts in the Boston area highlights higher levels of antenatal anxiety, depression, and smoking among pregnant women who report low partner support. Partner support may be an important and potentially modifiable target for interventions to improve pregnancy outcomes

State and Regional Variation in Regulations Related to Feeding Infants in Child Care

The purpose of this study was to compare state and regional variation in infant feeding regulations for child care facilities and to compare these regulations to national standards

Changes of Children Referred for Multidisciplinary Weight Management

Objective. To examine body mass index (BMI) changes among pediatric multidisciplinary weight management participants and nonparticipants. Design. In this retrospective database analysis, we used multivariable mixed effect models to compare 2-year BMI zscore trajectories among 583 eligible overweight or obese children referred to the One Step Ahead program at the Boston Children's Primary Care Center between 2003 and 2009. Results. Of the referred children, 338 (58%) attended the program; 245 (42%) did not participate and were instead followed by their primary care providers within the group practice. The mean BMI z-score of program participants decreased modestly over a 2-year period and was lower than that of nonparticipants. The group-level difference in the rate of change in BMI z-score between participants and nonparticipants was statistically significant for 0-6 months ( = 0.001) and 19-24 months ( = 0.008); it was marginally significant for 13-18 months ( = 0.051) after referral. Younger participants (<5 years) had better outcomes across all time periods examined. Conclusion. Children attending a multidisciplinary program experienced greater BMI z-score reductions compared with usual primary care in a real world practice; younger participants had significantly better outcomes. Future research should consider early intervention and cost-effectiveness analyses

Assessing care providers’ perceptions and beliefs about physical activity in infants and toddlers: baseline findings from the Baby NAP SACC study

Background: As children now spend increasing amounts of time in out-of-home care, care providers play an important role in promoting positive health behaviors. Little is currently known about providers’ perceptions and beliefs about physical activity, particularly for very young children. This study describes providers’ perceptions and beliefs about infants’ and toddlers’ physical activity, and assesses their knowledge of physical activity guidelines, to establish if and where providers may need support to promote physical activity in child care settings. Methods: We analyzed baseline data from a pilot randomized-controlled trial conducted in 32 child care centers in Massachusetts, USA. Providers completed physical activity-related questionnaires from which we compared twenty perception and belief questions for infant and toddler care providers. Results: 203 care providers (96% female, mean ± SD age: 32.7 ± 11.2 years) from 29 centers completed questionnaires. A large proportion of providers (n = 114 (61.9%)) believed that infants should be active for 45 minutes or less each day, and only 56 providers (29.7%) perceived toddlers to require more than 90 minutes of activity per day. 97% of providers perceived it was their job to ensure children engaged in a healthy amount of physical activity and most (94.1%) perceived physical activity to be important to own their health, despite 13.3% finding it hard to find the energy to be physically active. Conclusions: This study is the first to assess the physical activity perceptions and attitudes of providers caring for infants and toddlers. Though all providers believed toddlers should engage in more physical activity than infants, most providers believed that young children require only a short amount of physical activity each day, below recommended guidelines. How provider perceptions influence children’s physical activity behavior requires investigation

Numerical loop quantum cosmology: an overview

A brief review of various numerical techniques used in loop quantum cosmology and results is presented. These include the way extensive numerical simulations shed insights on the resolution of classical singularities, resulting in the key prediction of the bounce at the Planck scale in different models, and the numerical methods used to analyze the properties of the quantum difference operator and the von Neumann stability issues. Using the quantization of a massless scalar field in an isotropic spacetime as a template, an attempt is made to highlight the complementarity of different methods to gain understanding of the new physics emerging from the quantum theory. Open directions which need to be explored with more refined numerical methods are discussed.Comment: 33 Pages, 4 figures. Invited contribution to appear in Classical and Quantum Gravity special issue on Non-Astrophysical Numerical Relativit

Early-Life Obesity Prevention: Critique of Intervention Trials During the First One Thousand Days

Purpose of review - To critique the evidence from recent and ongoing obesity prevention interventions in the first 1000 days in order to identify evidence gaps and weaknesses, and to make suggestions for more informative future intervention trials. Recent findings - Completed and ongoing intervention trials have had fairly modest effects, have been limited largely to high-income countries, and have used relatively short-term interventions and outcomes. Comparison of the evidence from completed prevention trials with the evidence from systematic reviews of behavioral risk factors shows that some life-course stages have been neglected (pre-conception and toddlerhood), and that interventions have neglected to target some important behavioral risk factors (maternal smoking during pregnancy, infant and child sleep).Finally, while obesity prevention interventions aim to modify body composition, few intervention trials have used body composition measures as outcomes, and this has limited their sensitivity to detect intervention effects. The new WHO Healthy Lifestyles Trajectory (HeLTI) initiative should address some of these weaknesses. Summary - Future early obesity prevention trials should be much more ambitious. They should, ideally: extend their interventions over the first 1000 days; have longer-term (childhood) outcomes, and improved outcome measures (body composition measures in addition to proxies for body composition such as the BMI for age); have greater emphasis on maternal smoking and child sleep; be global

Association of the First 1,000 Days Systems-Change Intervention on Maternal Gestational Weight Gain

Objective: To examine the associations of a clinical and public health systems-change intervention on the prevalence of excess gestational weight gain among high-risk, low-income women. Methods: In a quasi-experimental trial, we compared the prevalence of excess gestational weight gain among women before (n=643) and after (n=928) implementation of the First 1,000 Days program in two community health centers in Massachusetts. First 1,000 Days is a systematic program starting in early pregnancy and lasting through the first 24 months of childhood to prevent obesity among mother-child pairs. The program includes enhanced gestational weight gain tracking and counseling, screening for adverse health behaviors and sociocontextual factors, patient navigation and educational materials to support behavior change and social needs, and individualized health coaching for women at high risk for excess gestational weight gain based on their prepregnancy body mass index (BMI) or excess first-trimester weight gain. The primary outcome was gestational weight gain greater than the 2009 Institute of Medicine (now known as the National Academy of Medicine) guidelines according to prepregnancy BMI. Results: Among 1,571 women in the analytic sample, mean (SD) age was 30.0 (5.9) years and prepregnancy BMI was 28.1 (6.1); 65.8% of women started pregnancy with BMIs of 25 or higher, and 53.2% were Hispanic. We observed a lower prevalence (55.8-46.4%; unadjusted odds ratio [OR] 0.69, 95% CI 0.49-0.97), similar to results in a multivariable analysis (adjusted OR 0.69, 95% CI 0.49-0.99), of excess gestational weight gain among women with prepregnancy BMIs between 25 and 29.9. Among women who were overweight at the start of pregnancy, the lowest odds of excess gestational weight gain were observed among those with the most interaction with the program's components. Program enrollment was not associated with reduced excess gestational weight gain among women with prepregnancy BMIs of 30 or higher. Conclusions: Implementation of a systems-change intervention was associated with modest reduction in excess gestational weight gain among women who were overweight but not obese at the start of pregnancy

Loop Quantum Cosmology: A Status Report

The goal of this article is to provide an overview of the current state of the art in loop quantum cosmology for three sets of audiences: young researchers interested in entering this area; the quantum gravity community in general; and, cosmologists who wish to apply loop quantum cosmology to probe modifications in the standard paradigm of the early universe. An effort has been made to streamline the material so that, as described at the end of section I, each of these communities can read only the sections they are most interested in, without a loss of continuity.Comment: 138 pages, 15 figures. Invited Topical Review, To appear in Classical and Quantum Gravity. Typos corrected, clarifications and references adde