Longitudinal study of children's disordered eating and muscle preoccupation

This thesis examined the role of individual factors in the development of dieting and muscal preoccupation in children. The main factor associated with these weight and shape concerns was perfectionism. It is important to identify risk factors in order to design intervention programs to decrease these behaviours in children.

Recombinant human growth hormone for the treatment of growth disorders in children: a systematic review and economic evaluation

Recombinant human growth hormone (rhGH) is licensed for short stature associated with growth hormone deficiency (GHD), Turner syndrome (TS), Prader-Willi syndrome (PWS), chronic renal insufficiency (CRI), short stature homeobox-containing gene deficiency (SHOX-D) and being born small for gestational age (SGA). To assess the clinical effectiveness and cost-effectiveness of rhGH compared with treatment strategies without rhGH for children with GHD, TS, PWS, CRI, SHOX-D and those born SGA. The systematic review used a priori methods. Key databases were searched (e.g. MEDLINE, EMBASE, NHS Economic Evaluation Database and eight others) for relevant studies from their inception to June 2009. A decision-analytical model was developed to determine cost-effectiveness in the UK. Two reviewers assessed titles and abstracts of studies identified by the search strategy, obtained the full text of relevant papers, and screened them against inclusion criteria. Data from included studies were extracted by one reviewer and checked by a second. Quality of included studies was assessed using standard criteria, applied by one reviewer and checked by a second. Clinical effectiveness studies were synthesised through a narrative review. Twenty-eight randomised controlled trials (RCTs) in 34 publications were included in the systematic review. GHD: Children in the rhGH group grew 2.7 cm/year faster than untreated children and had a statistically significantly higher height standard deviation score (HtSDS) after 1 year: -2.3 ± 0.45 versus -2.8 ± 0.45. TS: In one study, treated girls grew 9.3 cm more than untreated girls. In a study of younger children, the difference was 7.6 cm after 2 years. HtSDS values were statistically significantly higher in treated girls. PWS: Infants receiving rhGH for 1 year grew significantly taller (6.2 cm more) than those untreated. Two studies reported a statistically significant difference in HtSDS in favour of rhGH. CRI: rhGH-treated children in a 1-year study grew an average of 3.6 cm more than untreated children. HtSDS was statistically significantly higher in treated children in two studies. SGA: Criteria were amended to include children of 3+ years with no catch-up growth, with no reference to mid-parental height. Only one of the RCTs used the licensed dose; the others used higher doses. Adult height (AH) was approximately 4 cm higher in rhGH-treated patients in the one study to report this outcome, and AH-gain SDS was also statistically significantly higher in this group. Mean HtSDS was higher in treated than untreated patients in four other studies (significant in two). SHOX-D: After 2 years' treatment, children were approximately 6 cm taller than the control group and HtSDS was statistically significantly higher in treated children. The incremental cost per quality adjusted life-year (QALY) estimates of rhGH compared with no treatment were: 23,196 pounds for GHD, 39,460 pounds for TS, 135,311 pounds for PWS, 39,273 pounds for CRI, 33,079 pounds for SGA and 40,531 pounds for SHOX-D. The probability of treatment of each of the conditions being cost-effective at 30,000 pounds was: 95% for GHD, 19% for TS, 1% for PWS, 16% for CRI, 38% for SGA and 15% for SHOX-D.

The non-advertising effects of screen-based sedentary activities on acute eating behaviours in children, adolescents, and young adults. A systematic review.

Sedentary screen time may be an important determinant of childhood obesity. A number of potential mechanisms to explain the link between screen time and increased bodyweight have been proposed; however, the relationship appears to be best explained by the effects on dietary intake, which is attributed to either food advertising or effects independent of food advertising. Technological advances have allowed for greater accessibility and exposure to advertisement-free screen-based media. This review was conducted to systematically synthesise the evidence from laboratory based studies which have investigated the non-advertising effects of screen time (TV viewing, sedentary video games, and computer use) on dietary intake in children, adolescents, and young adults. MEDLINE, PubMed, PsychInfo, CINAHL, and Embase were searched from inception through 5 July 2013. Ten trials met the inclusion criteria and were included in the review. Risk of study bias was judged to range from low to high. Screen time in the absence of food advertising was consistently found to be associated with increased dietary intake compared with non-screen behaviours. Suggested explanations for this relationship included: distraction, interruption of physiologic food regulation, screen time as a conditioned cue to eat, disruption of memory formation, and the effects of the stress-induced reward system. Due to the limited number of high-quality studies available for this review, our findings are preliminary. More work is required to better establish the link between dietary intake and advertisement-free screen time and assess whether differences exist between the different screen-based activities.

Is a change in mode of travel to school associated with a change in overall physical activity levels in children? Longitudinal results from the SPEEDY study

Background
Children who use active modes of travel (walking or cycling) to school are more physically active than those who use passive (motorised) modes. However, less is known on whether a change in mode of travel to school is associated with a change in children’s physical activity levels. The purpose of this analysis was to investigate the association between change in mode of travel to school and change in overall physical activity levels in children.

Methods
Data from 812 9–10 year old British children (59% girls) who participated in the SPEEDY study were analysed. During the summer terms of 2007 and 2008 participants completed a questionnaire and wore an accelerometer for at least three days. Two-level multiple linear regression models were used to explore the association between change in usual mode of travel to school and change in objectively measured time spent in MVPA.

Results
Compared to children whose reported mode of travel did not change, a change from a passive to an active mode of travel was associated with an increase in daily minutes spent in MVPA (boys: beta 11.59, 95% CI 0.94 to 22.24; girls: beta 11.92, 95% CI 5.00 to 18.84). This increase represented 12% of boys’ and 13% of girls’ total daily time spent in MVPA at follow-up.

Conclusion
This analysis provides further evidence that promoting active travel to school may have a role in contributing to increasing physical activity levels in children.

Maternal feeding practices predict weight gain and obesogenic eating behaviours in young children : a prospective study

Background Maternal feeding practices have been proposed to play an important role in early child weight gain and obesogenic eating behariours. However, to date longitudinal investigations in young children exploring these relationships have been lacking. The aim of the present study was to explore prospective relationships between maternal feeding practices, child weight gain and obesogenic eating behaviours in 2-year-old children. The competing hypothesis that child eating behaviours predict changes in maternal feeding practices was also examined.

Methods A sample of 323 mother (mean age = 35 years, + 0.37) and child dyads (mean age = 2.03 years, + 0.37 at recruitment) were participants. Mothers completed a questionnaire assessing parental feeding practices and child eating behaviours at baseline and again one year later. Child BMI (predominantly objectively measured) was obtained at both time points.

Results Increases in child BMI z-scores over the follow-up period were predicted by maternal instrumental feeding practices. Furthermore, restriction, emotional feeding, encouragement to eat, weight-based restriction and fat restriction were associated prospectively with the development of obesogenic eating behaviours in children including emotional eating, tendency to overeat and food approach behaviours (such as enjoyment of food and good appetite). Maternal monitoring, however, predicted decreases in food approach eating behaviours. Partial support was also observed for child eating behaviours predicting maternal feeding practices.

Conclusions Maternal feeding practices play an important role in the development of weight gain and obesogenic eating behaviours in young children and are potential targets for effective prevention interventions aiming to decrease child obesity.

Estimating the effects of energy imbalance on changes in body weight in children

BACKGROUND: Estimating changes in weight from changes in energy balance is important for predicting the effect of obesity prevention interventions. OBJECTIVE: The objective was to develop and validate an equation for predicting the mean weight of a population of children in response to a change in total energy intake (TEI) or total energy expenditure (TEE). DESIGN: In 963 children with a mean (+/-SD) age of 8.1 +/- 2.8 y (range: 4-18 y) and weight of 31.5 +/- 17.6 kg, TEE was measured by using doubly labeled water. Log weight (dependent variable) and log TEE (independent variable) were analyzed in a linear regression model with height, age, and sex as covariates. It was assumed that points of dynamic balance, called "settling points," occur for populations wherein energy is in balance (TEE = TEI), weight is stable (ignoring growth), and energy flux (EnFlux) equals TEE. RESULTS: TEE (or EnFlux) explained 74% of the variance in weight. The unstandardized regression coefficient was 0.45 (95% CI: 0.38, 0.51; R(2) = 0.86) after including covariates. Conversion into proportional changes (time(1) to time(2)) gave the equation (weight(2)/weight(1)) = (EnFlux(2)/EnFlux(1))(0.45). In 3 longitudinal studies (n = 212; mean follow-up of 3.4 y), the equation predicted the mean follow-up measured weight to within 0.5%. CONCLUSIONS: The relation of EnFlux with weight was positive, which implied that a high TEI (rather than low physical activity and low TEE) was the main determinant of high body weight. Two populations of children with a 10% difference in mean EnFlux would have a 4.5% difference in mean weight.

Parental influences upon their children's body image concerns and behaviours

An examination of the influence of parents revealed that sons' and daughters' perceptions of the direct and indirect pressures exerted by both mothers and fathers were more predictive of their body image concerns and body change strategies than the messages reported by parents. The professional portfolio presents four case studies of children referred to a Child and Adolescent Mental Health Service with depressive symptomatology in relation to attachment theory.

Preventing weight and muscle concerns among preadolescents

The high level of weight and shape concerns amongst preadolescent children has prompted interest in the development of prevention programs for this age group. In the 1990s weight and shape concerns were considered primarily an adolescent phenomenon. However, prevention programs which have been designed with adolescent and adult populations have been found to show limited success. Some researchers have argued that programs which target preadolescent children are more likely to be effective than programs that target adolescents, as by adolescence many attitudes and behaviours have become entrenched so they may be more difficult to modify. On the other hand, children's weight and shape concerns are believed to be more malleable and amenable to change. To date there have been limited controlled studies implementing prevention programs designed to reduce weight and shape concerns with preadolescent populations. The new study conducted as part of this thesis involves the development and implementation of the ‘Everybody’ s Different, Nobody Else Is Me’ preadolescent prevention program. The program was designed to address some of the methodological biases of past research and incorporate three risk factors, social comparisons, negative affect, and self-esteem, to reduce and/or prevent the development of weight and muscle concerns among children. These three risk factors have been found to be associated with weight and shape concerns of adolescents and adults, and there is also increasing evidence that they are important factors among children. Research also suggests that social comparisons, negative affect, and self-esteem are interrelated, which highlights the importance of targeting the variables in one program. The new five session prevention initiative was implemented with 156 grade four children. Both the treatment and control conditions consisted of 78 children. Preliminary evidence from the new prevention initiative indicated that the program reduced muscle bulk and exercise (ie. An over-emphasis on exercise to lose weight rather than health promotion), and negative affect in the long term as assessed by the six month follow-up. At the six month follow-up, children in both the treatment and control conditions reported reduced negative affect, dieting, and muscle bulk and exercise scores and increased positive affect. Consistent with short term follow-up results, boys reported greater muscle bulk and exercise scores than girls at the six month follow-up. Girls, in both conditions, were also found to report greater positive affect than boys. These findings are discussed in relation to past research, and suggestions for future prevention initiatives are highlighted.

Relationship between verbal working memory and the SCAN-C in children with specific language impairment

Purpose: An ongoing concern with the evaluation of auditory processing disorders is the extent that assessment instruments are influenced by higher order cognitive functions. This study examined the relationship between verbal working memory and performance on the Test for Auditory Processing Disorders in Children--Revised (SCAN-C; Keith, 2000b) in children with specific language impairment (SLI) and typically developing (TD) children.

Method: Sixteen children with SLI and 16 TD children ages 8/4 to 11 years participated in the study. The children were presented with the SCAN-C and tests measuring verbal working memory.

Results: Initial comparisons revealed that the SLI group obtained significantly lower scores than the TD group on the SCAN-C. However, after controlling for verbal working memory, significant differences between the 2 groups were no longer observed. Correlational analyses revealed that the composite score from the SCAN-C was related to all tests assessing verbal working memory.

Conclusions: Performance on the SCAN-C may be related to working memory functioning. As a consequence, it is unclear whether difficulty on this task should be viewed as a problem with auditory processing or a problem with verbal working memory.

Preteen boys, body image, and eating disorders

In recent years, academic and public attention has increasingly focused on the issue of men’s preoccupation with body image and the increasing incidence of eating disorders among men. Although most of this focus has been on young and adult males, media discourse has tended to extend explanations for men’s aspirations for social body ideals to explanations for eating disorders in young boys. In this article, we take a critical look at the way the boys/body image/eating disorder nexus has been represented in some of the mainstream media. In particular, we propose that the boys/body image/eating disorder nexus has been constituted as a truth that tends to underplay the complexity of the relationship between eating disorders and boys’ dissatisfaction with their bodies, as recognized by researchers and health practitioners, and as evident from our own study of preteen boys diagnosed with an eating disorder. In this article, we use interviews with the six boys and their mothers collected for our study to construct short family biographies. These

Strategies which aim to positively impact on weight, physical activity, diet and sedentary behaviours in children from zero to five years. A systematic review of the literature

Preventing the development of obesity in children is an international health priority. To assess the effectiveness of interventions designed to prevent obesity, promote healthy eating and/or physical activity and/or to reduce sedentary behaviours in 0–5-year-old children, a systematic review of the literature was performed. Literature searches were limited to articles published between January 1995 and June 2006, printed in English and sampling children aged 0–5-years. Searches excluded literature concerned with breastfeeding, eating disorders, and interventions which were school-based or concerned with obesity treatment. Two reviewers independently extracted data and assessed study strengths and weaknesses. Nine included studies were grouped based on the settings in which they were delivered. Most studies involved multi-approach interventions, were conducted in the USA and varied in study designs and quality. All showed some level of effectiveness on at least one obesity-behaviour in young children. These studies support, at a range of levels, the premise that parents are receptive to and capable of some behavioural changes that may promote healthy weight in their young children. The small quantity of research heralds the need, particularly given the potential for early intervention to have long-lasting impacts on individual and population health, to build in a substantial way upon this evidence base.

Effects of early-life environment and epigenetics on cardiovascular disease risk in children: highlighting the role of twin studies

Cardiovascular disease (CVD) is the leading cause of death worldwide and originates in early life. The exact mechanisms of this early-life origin are unclear, but a likely mediator at the molecular level is epigenetic dysregulation of gene expression. Epigenetic factors have thus been posited as the likely drivers of early-life programming of adult-onset diseases. This review summarizes recent advances in epidemiology and epigenetic research of CVD risk in children, with a particular focus on twin studies. Classic twin studies enable partitioning of phenotypic variance within a population into additive genetic, shared, and nonshared environmental variances, and are invaluable in research in this area. Longitudinal cohort twin studies, in particular, may provide important insights into the role of epigenetics in the pathogenesis of CVD. We describe candidate gene and epigenome-wide association studies (EWASs) and transgenerational epigenetic inheritance of CVD, and discuss the potential for evidence-based interventions. Identifying epigenetic changes associated with CVD-risk biomarkers in children will provide new opportunities to unravel the underlying biological mechanism of the origins of CVD and enable identification of those at risk for early-life interventions to alter the risk trajectory and potentially reduce CVD incidence later in life.