Amika S. Singh

Tracking of childhood overweight into adulthood: a systematic review of the literature.

Overweight and obesity in youth are important public health concerns and are of particular interest because of possible long‐term associations with adult weight status and morbidity. The aim of this study was to systematically review the literature and update evidence concerning persistence of childhood overweight. A computerized bibliographical search – restricted to studies with a prospective or retrospective longitudinal design – was conducted. Two authors independently extracted data and assessed the methodological quality of the included studies in four dimensions (i) study population and participation rate; (ii) study attrition; (iii) data collection and (iv) data analysis. Conclusions were based on a rating system of three levels of evidence. A total of 25 publications were selected for inclusion in this review. According to a methodological quality assessment, 13 studies were considered to be of high quality. The majority of these high‐quality studies were published after 2001, indicating that recently published data, in particular, provide us with reliable information. All included studies consistently report an increased risk of overweight and obese youth becoming overweight adults, suggesting that the likelihood of persistence of overweight into adulthood is moderate for overweight and obese youth. However, predictive values varied considerably. Limiting aspects with respect to generalizability and methodological issues are discussed.

Sedentary Behaviors and Health Outcomes Among Adults: A Systematic Review of Prospective Studies

CONTEXT Nowadays, people spend a substantial amount of time per day on sedentary behaviors and it is likely that the time spent sedentary will continue to rise. To date, there is no review of prospective studies that systematically examined the relationship between diverse sedentary behaviors and various health outcomes among adults. PURPOSE This review aimed to systematically review the literature as to the relationship between sedentary behaviors and health outcomes considering the methodologic quality of the studies. EVIDENCE ACQUISITION In February 2010, a search for prospective studies was performed in diverse electronic databases. After inclusion, in 2010, the methodologic quality of each study was assessed. A best-evidence synthesis was applied to draw conclusions. EVIDENCE SYNTHESIS 19 studies were included, of which 14 were of high methodologic quality. Based on inconsistency in findings among the studies and lack of high-quality prospective studies, insufficient evidence was concluded for body weight-related measures, CVD risk, and endometrial cancer. Further, moderate evidence for a positive relationship between the time spent sitting and the risk for type 2 diabetes was concluded. Based on three high-quality studies, there was no evidence for a relationship between sedentary behavior and mortality from cancer, but strong evidence for all-cause and CVD mortality. CONCLUSIONS Given the trend toward increased time in sedentary behaviors, additional prospective studies of high methodologic quality are recommended to clarify the causal relationships between sedentary behavior and health outcomes. Meanwhile, evidence to date suggests that interventions aimed at reducing sedentary behavior are needed.

Review and special articleSedentary Behaviors and Health Outcomes Among Adults: A Systematic Review of Prospective Studies

CONTEXT Nowadays, people spend a substantial amount of time per day on sedentary behaviors and it is likely that the time spent sedentary will continue to rise. To date, there is no review of prospective studies that systematically examined the relationship between diverse sedentary behaviors and various health outcomes among adults. PURPOSE This review aimed to systematically review the literature as to the relationship between sedentary behaviors and health outcomes considering the methodologic quality of the studies. EVIDENCE ACQUISITION In February 2010, a search for prospective studies was performed in diverse electronic databases. After inclusion, in 2010, the methodologic quality of each study was assessed. A best-evidence synthesis was applied to draw conclusions. EVIDENCE SYNTHESIS 19 studies were included, of which 14 were of high methodologic quality. Based on inconsistency in findings among the studies and lack of high-quality prospective studies, insufficient evidence was concluded for body weight-related measures, CVD risk, and endometrial cancer. Further, moderate evidence for a positive relationship between the time spent sitting and the risk for type 2 diabetes was concluded. Based on three high-quality studies, there was no evidence for a relationship between sedentary behavior and mortality from cancer, but strong evidence for all-cause and CVD mortality. CONCLUSIONS Given the trend toward increased time in sedentary behaviors, additional prospective studies of high methodologic quality are recommended to clarify the causal relationships between sedentary behavior and health outcomes. Meanwhile, evidence to date suggests that interventions aimed at reducing sedentary behavior are needed.

Physical Activity and Performance at School A Systematic Review of the Literature Including a Methodological Quality Assessment

OBJECTIVE To describe the prospective relationship between physical activity and academic performance. DATA SOURCES Prospective studies were identified from searches in PubMed, PsycINFO, Cochrane Central, and Sportdiscus from 1990 through 2010. STUDY SELECTION We screened the titles and abstracts for eligibility, rated the methodological quality of the studies, and extracted data. MAIN EXPOSURE Studies had to report at least 1 physical activity or physical fitness measurement during childhood or adolescence. MAIN OUTCOME MEASURES Studies had to report at least 1 academic performance or cognition measure during childhood or adolescence. RESULTS We identified 10 observational and 4 intervention studies. The quality score of the studies ranged from 22% to 75%. Two studies were scored as high quality. Methodological quality scores were particularly low for the reliability and validity of the measurement instruments. Based on the results of the best-evidence synthesis, we found evidence of a significant longitudinal positive relationship between physical activity and academic performance. CONCLUSIONS Participation in physical activity is positively related to academic performance in children. Because we found only 2 high-quality studies, future high-quality studies are needed to confirm our findings. These studies should thoroughly examine the dose-response relationship between physical activity and academic performance as well as explanatory mechanisms for this relationship.

Relationship between young peoples' sedentary behaviour and biomedical health indicators: a systematic review of prospective studies

The aim of this systematic review was to describe the prospective relationship between childhood sedentary behaviour and health indicators. We identified prospective studies from searches in PubMed, EMBASE, PsycInfo and Cochrane, from January 1989 through April 2010. Two reviewers independently screened the titles and abstracts for eligibility, rated the methodological quality of the studies, and extracted data.

Differences in Weight Status and Energy-Balance Related Behaviors among Schoolchildren across Europe: The ENERGY-Project

Background Current data on the prevalence of overweight and energy-balance behaviors among European children is necessary to inform overweight prevention interventions. Methodology/Principal Findings A school-based survey among 10–12 year old children was conducted in seven European countries using a standardized protocol. Weight, height, and waist circumference were measured; Engagement in physical activity, sedentary and dietary behaviors, and sleep duration were self-reported. Descriptive analyses were conducted, looking at differences according to country, gender, and parental education. 7234 children (52%girls; 11.6±0.7 years) participated. 25.8% and 5.4% of boys, and 21.8% and 4.1% of girls were overweight (including obese) and obese (according to International Obesity Task Force criteria), respectively. Higher prevalence of overweight/obesity was observed in Greece, Hungary, Slovenia and Spain than in Belgium, Netherlands and Norway. Large differences between countries were found in intakes of sugar-sweetened beverages, breakfast, active transport, TV and computer time. More favorable overweight status and behavior patterns were found in girls than boys and in children of higher educated parents than in children of lower educated parents. Conclusions/Significance High levels and striking differences in overweight status and potential risk behaviors were found among schoolchildren across Europe.

Dutch Obesity Intervention in Teenagers: Effectiveness of a School-Based Program on Body Composition and Behavior

OBJECTIVE To determine whether a multicomponent health promotion intervention for Dutch adolescents (defined as persons between 12 and 14 years of age) would be successful in influencing body composition and dietary and physical activity behavior in both the short and long terms. DESIGN Randomized controlled trial. SETTING Ten intervention and 8 control prevocational secondary schools. PARTICIPANTS A total of 1108 adolescents (mean age, 12.7 years). Intervention An interdisciplinary program with an adapted curriculum for 11 lessons in biology and physical education and environmental change options. MAIN OUTCOME MEASURES Body height and weight, waist circumference, 4 skinfold thickness measurements, and dietary and physical activity behavior data. RESULTS Multilevel analyses showed that the intervention remained effective in preventing unfavorable increases in important measures of body composition after 20-month follow-up in girls (biceps skinfold and sum of 4 skinfolds) and boys (triceps, biceps, and subscapular skinfolds). Consumption of sugar-containing beverages was significantly lower in intervention schools both after intervention (boys: -287 mL/d; 95% confidence interval [CI], -527 to -47; girls: -249; -400 to -98) and at 12-month follow-up (boys: -233; -371 to -95; girls: -271; -390 to -153). For boys, screen-viewing behavior was significantly lower in the intervention group after 20 months (-25 min/d; 95% CI, -50 to -0.3). No significant intervention effects on consumption of snacks or active commuting to school were found. CONCLUSION The Dutch Obesity Intervention in Teenagers program resulted in beneficial effects on the sum of skinfold thickness measurements in girls and consumption of sugar-containing beverages in both boys and girls in both the short and long terms.

Design of the Dutch Obesity Intervention in Teenagers (NRG-DOiT): systematic development, implementation and evaluation of a school-based intervention aimed at the prevention of excessive weight gain in adolescents

BackgroundOnly limited data are available on the development, implementation, and evaluation processes of weight gain prevention programs in adolescents. To be able to learn from successes and failures of such interventions, integral written and published reports are needed.MethodsApplying the Intervention Mapping (IM) protocol, this paper describes the development, implementation, and evaluation of the Dutch Obesity Intervention in Teenagers (DOiT), a school-based intervention program aimed at the prevention of excessive weight gain.The intervention focussed on the following health behaviours: (1) reduction of the consumption of sugar-sweetened beverages, (2) reduction of energy intake derived from snacks, (3) decrease of levels of sedentary behaviour, and (4) increase of levels of physical activity (i.e. active transport behaviour and sports participation).The intervention program consisted of an individual classroom-based component (i.e. an educational program, covering 11 lessons of both biology and physical education classes), and an environmental component (i.e. encouraging and supporting changes at the school canteens, as well as offering additional physical education classes).We evaluated the effectiveness of the intervention program using a randomised controlled trial design. We assessed the effects of the intervention on body composition (primary outcome measure), as well as on behaviour, behavioural determinants, and aerobic fitness (secondary outcome measures). Furthermore, we conducted a process evaluation.DiscussionThe development of the DOiT-intervention resulted in a comprehensive school-based weight gain prevention program, tailored to the needs of Dutch adolescents from low socio-economic background.

European energy balance research to prevent excessive weight gain among youth (ENERGY) project: Design and methodology of the ENERGY cross-sectional survey

BackgroundObesity treatment is by large ineffective long term, and more emphasis on the prevention of excessive weight gain in childhood and adolescence is warranted. To inform energy balance related behaviour (EBRB) change interventions, insight in the potential personal, family and school environmental correlates of these behaviours is needed. Studies on such multilevel correlates of EBRB among schoolchildren in Europe are lacking. The ENERGY survey aims to (1) provide up-to-date prevalence rates of measured overweight, obesity, self-reported engagement in EBRBs, and objective accelerometer-based assessment of physical activity and sedentary behaviour and blood-sample biomarkers of metabolic function in countries in different regions of Europe, (2) to identify personal, family and school environmental correlates of these EBRBs. This paper describes the design, methodology and protocol of the survey.Method/DesignA school-based cross-sectional survey was carried out in 2010 in seven different European countries; Belgium, Greece, Hungary, the Netherlands, Norway, Slovenia, and Spain. The survey included measurements of anthropometrics, child, parent and school-staff questionnaires, and school observations to measure and assess outcomes (i.e. height, weight, and waist circumference), EBRBs and potential personal, family and school environmental correlates of these behaviours including the social-cultural, physical, political, and economic environmental factors. In addition, a selection of countries conducted accelerometer measurements to objectively assess physical activity and sedentary behaviour, and collected blood samples to assess several biomarkers of metabolic function.DiscussionThe ENERGY survey is a comprehensive cross-sectional study measuring anthropometrics and biomarkers as well as assessing a range of EBRBs and their potential correlates at the personal, family and school level, among 10-12 year old children in seven European countries. This study will result in a unique dataset, enabling cross country comparisons in overweight, obesity, risk behaviours for these conditions as well as the correlates of engagement in these risk behaviours.

Test-retest reliability and construct validity of the ENERGY-child questionnaire on energy balance-related behaviours and their potential determinants: the ENERGY-project.

BackgroundInsight in childrens energy balance-related behaviours (EBRBs) and their determinants is important to inform obesity prevention research. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed.ObjectiveTo examine the test-retest reliability and construct validity of the child questionnaire used in the ENERGY-project, measuring EBRBs and their potential determinants among 10-12 year old children.MethodsWe collected data among 10-12 year old children (n = 730 in the test-retest reliability study; n = 96 in the construct validity study) in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC) and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent face-to-face interview was assessed using ICC and percentage agreement.ResultsOf the 150 questionnaire items, 115 (77%) showed good to excellent test-retest reliability as indicated by ICCs > .60 or percentage agreement ≥ 75%. Test-retest reliability was moderate for 34 items (23%) and poor for one item. Construct validity appeared to be good to excellent for 70 (47%) of the 150 items, as indicated by ICCs > .60 or percentage agreement ≥ 75%. From the other 80 items, construct validity was moderate for 39 (26%) and poor for 41 items (27%).ConclusionsOur results demonstrate that the ENERGY-child questionnaire, assessing EBRBs of the child as well as personal, family, and school-environmental determinants related to these EBRBs, has good test-retest reliability and moderate to good construct validity for the large majority of items.