Screen Time Weight-loss Intervention Targeting Children at Home (SWITCH): process evaluation of a randomised controlled trial intervention.

BACKGROUND: The Screen Time Weight-loss Intervention Targeting Children at Home (SWITCH) trial tested a family intervention to reduce screen-based sedentary behaviour in overweight children. The trial found no significant effect of the intervention on children's screen-based sedentary behaviour. To explore these null findings, we conducted a pre-planned process evaluation, focussing on intervention delivery and uptake. METHODS: SWITCH was a randomised controlled trial of a 6-month family intervention to reduce screen time in overweight children aged 9-12 years (n = 251). Community workers met with each child's primary caregiver to deliver the intervention content. Community workers underwent standard training and were monitored once by a member of the research team to assess intervention delivery. The primary caregiver implemented the intervention with their child, and self-reported intervention use at 3 and 6 months. An exploratory analysis determined whether child outcomes at 6 months varied by primary caregiver use of the intervention. RESULTS: Monitoring indicated that community workers delivered all core intervention components to primary caregivers. However, two thirds of primary caregivers reported using any intervention component "sometimes" or less frequently at both time points, suggesting that intervention uptake was poor. Additionally, analyses indicated no effect of primary caregiver intervention use on child outcomes at 6 months, suggesting the intervention itself lacked efficacy. CONCLUSIONS: Poor uptake, and the efficacy of the intervention itself, may have played a role in the null findings of the SWITCH trial on health behaviour and body composition. TRIAL REGISTRATION: The trial was registered in the Australian and New Zealand Clinical Trials Registry (no. ACTRN12611000164998 ); registration date: 10/02/2011.

FTO genotype and weight loss: systematic review and meta-analysis of 9563 individual participant data from eight randomised controlled trials

OBJECTIVE:  To assess the effect of the FTO genotype on weight loss after dietary, physical activity, or drug based interventions in randomised controlled trials.

DESIGN:  Systematic review and random effects meta-analysis of individual participant data from randomised controlled trials.

DATA SOURCES:  Ovid Medline, Scopus, Embase, and Cochrane from inception to November 2015.

ELIGIBILITY CRITERIA FOR STUDY SELECTION:  Randomised controlled trials in overweight or obese adults reporting reduction in body mass index, body weight, or waist circumference by FTO genotype (rs9939609 or a proxy) after dietary, physical activity, or drug based interventions. Gene by treatment interaction models were fitted to individual participant data from all studies included in this review, using allele dose coding for genetic effects and a common set of covariates. Study level interactions were combined using random effect models. Metaregression and subgroup analysis were used to assess sources of study heterogeneity.

RESULTS:  We identified eight eligible randomised controlled trials for the systematic review and meta-analysis (n=9563). Overall, differential changes in body mass index, body weight, and waist circumference in response to weight loss intervention were not significantly different between FTO genotypes. Sensitivity analyses indicated that differential changes in body mass index, body weight, and waist circumference by FTO genotype did not differ by intervention type, intervention length, ethnicity, sample size, sex, and baseline body mass index and age category.

CONCLUSIONS:  We have observed that carriage of the FTO minor allele was not associated with differential change in adiposity after weight loss interventions. These findings show that individuals carrying the minor allele respond equally well to dietary, physical activity, or drug based weight loss interventions and thus genetic predisposition to obesity associated with the FTO minor allele can be at least partly counteracted through such interventions.

Beliefs about the causes of weight change in the Australian population

OBJECTIVE: To describe self-reported weight change and beliefs about the causes of weight change and to examine whether these vary by sex and weight status.
DESIGN: This cross-sectional population study examined data from the 1995 Australian National Health and Nutrition Surveys.
SUBJECTS: A total of 10 624 randomly-selected adults provided data.
MEASURES: Objectively measured height and weight, perceptions of current weight status, self-reported weight change over the past year, and reasons for weight change.
RESULTS: Thirty-five percent of participants reported a weight gain in the last 12 months, with females, and those already overweight more likely to report a recent increase in weight. Approximately one in five participants reported a recent weight loss. Those who had recently gained weight were more likely to perceive themselves as overweight regardless of actual weight status. Commonly reported reasons for weight gain included a change in physical activity level (52% males and 35% females) and a change in the amount of food/drink consumed (30% males, 27% females). Similar reasons were given for weight loss.
CONCLUSIONS: Findings of widespread reported weight gain, particularly among those already overweight, suggest Australia's obesity epidemic may be worsening. Strategies are urgently required to better inform individuals about the factors impacting on their weight in order to prevent further weight gain.

The role of puberty, media and popularity with peers on strategies to increase weight, decrease weight and increase muscle tone among adolescent boys and girls

The present study was concerned with the impact of pubertal development, relationships with peers and perceived pressure from the media on body dissatisfaction and body change behaviors among adolescent boys and girls. In particular, the study investigated the underresearched area of strategies to increase weight and muscle. The exploration of body change strategies among adolescent boys has been a neglected area of research. Methods: Respondents were 1185 adolescents (527 males, 598 females) who were enrolled in Grades 7 and 9. Participants completed measures of pubertal development, media and peer influence, body dissatisfaction and strategies to lose weight, increase weight and to increase muscle. Results: The findings demonstrated that girls were more likely than boys to adopt strategies to lose weight, whereas boys were more likely to adopt strategies to increase muscle tone (but not weight). For boys in both Years 7 and 9, the main predictors of body change strategies were puberty and, to a lesser extent, perceived popularity with peers. The major influences for Years 7 and 9 girls were puberty and the media, but these mainly focused on weight loss. For Year 9 girls, perceived popularity with opposite-sex peers also predicted body dissatisfaction and strategies to increase muscle tone. Conclusion: The implications of these findings for understanding factors related to a range of body change strategies for adolescent boys and girls are discussed.

Public definitions of success in weight management

Objective: To examine perceptions of success in weight control and future weight-control intentions in a community sample. Design: Cross-sectional postal survey. Subjects: There were 1500 adults randomly selected from the Electoral Roll of Victoria (47% response). Setting: Community. Main outcome measures: Retrospective weight change over previous 12 months; perceived weight-control success; future weight-control intentions. Statistical analyses: Pearson's χ² tests were used to compare perceived weight-control success by sex, and by age, education level, initial BMI, amount of weight change and weight-loss behaviour within sex. ANOVA was used to compare mean weight change associated with perceived weight control success within sex, and within age, education, body mass index and weight-loss behaviour by sex. The distribution (frequency) of weight-control intentions are reported within perceived weight-control success and amount of weight change. Results: One in two (53%) reported maintaining their weight within 1kg in the preceding 12 months, 26% of men and 21% of women reported weight gain and 20% of men and 26% of women reported weight loss. Almost one-third (30%) of those who maintained their weight considered themselves unsuccessful. A majority of those who lost weight considered themselves successful at controlling their weight. However, more than 45% of men who gained weight also considered themselves successful. Those who considered themselves unsuccessful experienced less weight loss (1.1 ± 3.9kg) than those who considered themselves quite successful (-1.4 ± 4.5 kg, P < 0.001) or very successful (-1.3 ± 7.8 kg, P < 0.001). Conclusion: Public views of what constitutes successful weight control may need to be reoriented to be consistent with public health goals.

A longitudinal study of body image and strategies to lose weight and increase muscles in children

A longitudinal study was used to examine age differences in the role of body mass index (BMI) and sociocultural pressures in predicting changes in body image and strategies to both lose weight and increase muscles among 443 children aged between 8 and 12 years (207 boys, 236 girls) over a 16-month period. The strongest predictors of body image and these strategies were BMI, the media and mothers, and to a lesser extent fathers and best friends. Girls were focused on losing weight, whereas boys were focused on both increasing muscle and losing weight. Surprisingly, there was a reduction in strategies both to lose weight and increase muscles as children approached adolescence. The implications of these findings for preventative educational programs for boys and girls are discussed.

A prospective study of pressures from parents, peers, and the media on extreme weight change behaviors among adolescent boys and girls

The current study was designed to evaluate the role of sociocultural influences over a 16 month period on strategies to lose weight, extreme weight loss strategies, and strategies to increase muscles among adolescent boys (n=344) and girls (n=246). All participants completed measures of body dissatisfaction, body image importance, strategies to lose weight, extreme weight loss strategies, and strategies to increase muscles. Measures of perceived pressure to lose weight or increase muscles from mother, father, best male friend, best female friend and the media were also evaluated. Data were gathered on three occasions, 8 months apart. The results demonstrated that boys showed a decrease in strategies to lose weight and increase muscles over time, whereas girls showed an increase. Both boys and girls showed an increase in extreme weight loss strategies with girls demonstrating a greater increase than boys. The sociocultural influences generally were perceived by girls to relate to messages to lose weight, whereas for boys they were perceived to relate to increasing muscles. Messages from parents, particularly fathers, were strong predictors of both strategies to lose weight and increase muscles among boys, with the media and best male friend playing a limited role. For girls, the strongest influences were mothers and best female friends, with few influences from fathers or the media. The results of this study are discussed in terms of the importance of the various sociocultural influences in shaping body change strategies among young adolescent boys and girls, and the implications of these findings for intervention programs for adolescents.

Role of personal factors in women's self-reported weight management behaviour.

The aim of this study was to investigate the role of motivation, anxiety and self-efficacy in self-reported behaviour that may be important for weight loss and weight maintenance. One hundred and twenty-nine females aged 18–81 years were recruited from a variety of social, sporting venues and work places within a local community. Participants completed questionnaires assessing their levels of participation and perseverance in weight management activities, their motivation levels, their anxiety levels (State Anxiety Inventory) and their levels of self-efficacy for weight management behaviours. Motivation was found to play a major role in participation in weight management activities. Anxiety and self-efficacy played no significant role. The findings are discussed in relation to previous studies, and directions for future studies are indicated. It is argued that the level of motivation is a key factor that should be taken into account for each individual engaging in women's weight management programmes, and that further research should be undertaken to identify other relevant factors.

A longitudinal investigation of the development of weight and muscle concerns among preadolescent boys

The study examined the impact of body mass index (BMI), negative affect, self-esteem, and sociocultural influences in the development of weight and muscle concerns among preadolescent boys. Body dissatisfaction, importance placed on weight and muscles, weight loss strategies, and strategies to increase muscles were evaluated. Participants were 237 boys aged between 8 and 11 years who were tested at three assessment periods 8 months apart. The main predictor of boys’ body change strategies was their perceived pressures to modify weight and muscles from parents, peers, and the media. The other main predictor of boys’ body change strategies and the sole predictor of body dissatisfaction was BMI. Self-esteem and negative affect were found to be weak and generally nonsignificant predictors of boys’ body image concerns and body change strategies. Additional studies that examine the risk and protective factors associated with boys’ weight and muscle concerns are needed to assist in the development of prevention programs for preadolescent boys.

Evaluation of a brief pilot nutrition and exercise intervention for the prevention of weight gain in general practice patients

Objective To pilot-test a brief written prescription recommending lifestyle changes delivered by general practitioners (GPs) to their patients.

Design The Active Nutrition Script (ANS) included five nutrition messages and personalised exercise advice for a healthy lifestyle and/or the prevention of weight gain. GPs were asked to administer 10 scripts over 4 weeks to 10 adult patients with a body mass index (BMI) of between 23 and 30 kg m− 2. Information recorded on the script consisted of patients' weight, height, waist circumference, gender and date of birth, type and frequency of physical activity prescribed, and the selected nutrition messages. GPs also recorded reasons for administering the script. Interviews recorded GPs views on using the script.

Setting General practices located across greater Melbourne.

Subjects and results Nineteen GPs (63% female) provided a median of nine scripts over 4 weeks. Scripts were administered to 145 patients (mean age: 54 ± 13.2 years, mean BMI: 31.7 ± 6.3 kg m− 2; 57% female), 52% of whom were classified as obese (BMI >30 kg m− 2). GPs cited ‘weight reduction’ as a reason for writing the script for 78% of patients. All interviewed GPs (90%, n = 17) indicated that the messages were clear and simple to deliver.

Conclusions GPs found the ANS provided clear nutrition messages that were simple to deliver. However, GPs administered the script to obese patients for weight loss rather than to prevent weight gain among the target group. This has important implications for future health promotion interventions designed for general practice.

The relationship between quality of life and perceived body weight an dieting history in Dutch men and women

OBJECTIVES: (1) To study the relationship between quality of life (QoL) and measured and perceived weight and dieting history in Dutch men and women; (2) to assess the effect of weight loss over a 5 y period on QoL.

DESIGN: A cross-sectional study, in a sub-sample longitudinal over 5 y.

SUBJECTS: A total of 2155 men and 2446 women, aged 20-59 and recruited from the general population from three towns in The Netherlands.

MEASUREMENTS: Body weight, height, self-administered questionnaire including questions concerning demographic variables and weight loss practices as part of the Dutch Monitoring project on Risk Factors for Chronic Disease (MORGEN). The Rand-36 questionnaire was used as the QoL measure.

RESULTS: In men, measured overweight (body mass index, BMI>25 kg=m2) was not associated with any dimension of QoL after adjustment for age, educational level and perceived overweight. Perceived overweight was related to reduced scores for general health and vitality. This relationship was independent of measured obesity. A history of repeated weight loss was associated with reduced scores for role functioning due to both physical and emotional problems. In women, measured overweight was significantly associated with lower scores for five out of eight QoL dimensions and perceived overweight with three: general health, vitality and physical functioning. A history of frequent weight loss was related to significantly reduced scores in six dimensions. However, only with history of frequent weight loss, and uniquely in women, was there a significant reduction in
scores on mental health and limited emotional role functioning. Measured and perceived overweight and frequent weight loss were all related to reduced scores for physical functioning. Longitudinal data indicate that in older women weight gain of 10% body weight or more was associated with a significant deterioration in QoL.

CONCLUSIONS: When looking at measures of QoL in relation to overweight it is important to separate the effects of perception of weight status and history of weight loss. We observed that the latter two factors were associated with reduced scores on several dimensions of QoL, particularly in women. These associations were observed to be independent of body weight. International Journal of Obesity (2001) 25, 1386 – 1392

Multiple types of dieting prospectively predict weight gain during the freshman year of college.

The freshman year of college is a period of heightened risk for weight gain. This study examined measures of restrained eating, disinhibition, and emotional eating as predictors of weight gain during the freshman year. Using Lowe's multi-factorial model of dieting, it also examined three different types of dieting as predictors of weight gain. Sixty-nine females were assessed at three points during the school year. Weight gain during the freshman year averaged 2.1 kg. None of the traditional self-report measures of restraint, disinhibition, or emotional eating were predictive of weight gain. However, both a history of weight loss dieting and weight suppression (discrepancy between highest weight ever and current weight) predicted greater weight gain, and these effects appeared to be largely independent of one another. Individuals who said they were currently dieting to lose weight gained twice as much (5.0 kg) as former dieters (2.5 kg) and three times as much as never dieters (1.6 kg), but the import of this finding was unclear because there was only a small number of current dieters (N=7). Overall the results indicate that specific subtypes of dieting predicts weight gain during the freshman year better than more global measures of restraint or overeating.

A cross-sectional study of weight-and shape-related beliefs, behaviours and concerns of north Queensland adolescents

The purpose of this study was to examine differences in weight- and shape-related beliefs, behaviours and concerns across a high school population. Data were collected by questionnaire from 902 high school students from private schools in Townsville. Concerns about weight and shape were more apparent in students from the higher school years. More girls in higher than lower school years were dissatisfied with their bodies, concerned that many parts of their bodies were too fat and more of them attempted weight loss. More boys in higher than lower school years were satisfied with their bodies but they wanted to 'bulk up'. Societal expectations of weight and shape may adversely affect both males and females but in different ways. Thus, interventions aiming to promote the maintenance of a healthy body weight may need to account for the desire of the majority of young women to be thinner, while the majority of young men would like to be larger.

Reducing unhealthy weight gain in children through community capacity−building: results of a quasi−experimental intervention program, Be Active Eat Well

Background:
Be Active Eat Well (BAEW) was a multifaceted community capacity-building program promoting healthy eating and physical activity for children (aged 4–12 years) in the Australian town of Colac.
Objective:
To evaluate the effects of BAEW on reducing children's unhealthy weight gain.
Methods:
BAEW had a quasi-experimental, longitudinal design with anthropometric and demographic data collected on Colac children in four preschools and six primary schools at baseline (2003, n=1001, response rate: 58%) and follow-up (2006, n=839, follow-up rate: 84%). The comparison sample was a stratified random selection of preschools (n=4) and primary schools (n=12) from the rest of the Barwon South Western region of Victoria, with baseline assessment in 2003–2004 (n=1183, response rate: 44%) and follow-up in 2006 (n=979, follow-up rate: 83%).
Results:
Colac children had significantly lower increases in body weight (mean: -0.92 kg, 95% CI: -1.74 to -0.11), waist (-3.14 cm, -5.07 to -1.22), waist/height (-0.02, -0.03 to -0.004), and body mass index z-score (-0.11, -0.21 to -0.01) than comparison children, adjusted for baseline variable, age, height, gender, duration between measurements and clustering by school. In Colac, the anthropometric changes were not related to four indicators of socioeconomic status (SES), whereas in the comparison group 19/20 such analyses showed significantly greater gains in anthropometry in children from lower SES families. Changes in underweight and attempted weight loss were no different between the groups.
Conclusions:
Building community capacity to promote healthy eating and physical activity appears to be a safe and effective way to reduce unhealthy weight gain in children without increasing health inequalities.