Determinants of the prevalence and incidence of overweight in children and adolescents

Home visits to identify the roles lifestyle and stress play in families of children with obesity

One-sixth of Swiss children are affected by overweight, and despite the implementation of an evidence-based multiprofessional approach, there has only been moderate therapeutic success. An unfavourable home environment and psychosocial stresses on the family may impede lifestyle changes. This longitudinal observational study included children with obesity (body mass index [BMI] ≥97th percentile [P.]) or overweight (BMI ≥ 90th P.) with a comorbidity, and who were participating in a regional 12-month multiprofessional group programme (MGP). Two health professionals routinely visited the family home at baseline (T0) to identify obesogenic environmental factors and psychosocial stress using an observation and question checklist and the Heidelberger stress scale (HSS). At T0 and after an 8-month intensive intervention phase (T1), the BMI standard deviation score (BMI-SDS) and its associations with the environmental and psychosocial factors were assessed. Twenty-eight children (17 male) met the criteria for participation in the MGP. At T0, age was 11.2 ± 1.71 years, BMI 28.1 ± 4.7 kg/m2 and BMI-SDS 2.9 ± 0.8, means ±SD. By T1, the mean BMI-SDS had decreased significantly, by -0.11 (p < .05). The stress scores (30.46 ± 17.8) were elevated and the subcategories of financial and social stress showed a trend towards predicting BMI or BMI-SDS at T0 and T1, but none of the other supposed obesogenic risk factors significantly predicted weight status. Conducting home visits allowed health professionals to identify obesity-promoting home conditions and, more importantly, otherwise undisclosed high psychosocial stress and resource limitations in families that impacted the children's obesity before and after the MGP intervention.

Longitudinal association between the timing of adiposity peak and rebound and overweight at seven years of age

Background

The timing of adiposity peak (AP) or adiposity rebound (AR) is a determinant of overweight or obesity in adolescence and adulthood. However, limited studies have reported the association in young school-age children. We aimed to evaluate this association and explore the role of health behaviours in it.

Methods

Routinely collected, sequential, anthropometric data from the 1st to 80th months of age were used to estimate AP and AR timings in 2330 children born in Shanghai between 2010 and 2013. Multivariate regression analyses were applied to identify the associations between the AP or AR timings and the risk of developing overweight or obesity in first-grade school children. The roles of health behaviours, including dietary patterns, physical activity level, sleep and snacking habits, and screen time, were also evaluated.

Results

Children with a late AP or an early AR were at higher risk of overweight but not obesity or central obesity in their first grade. A high physical activity level was associated with a lower risk of having overweight in children with a late AP, and limited screen time was associated with a decreased risk of having overweight or obesity in children with an early AR. The absence of a late-night snacking habit in children with a non-early AR indicated a decreased risk of having overweight. However, this association was not observed among children with an early AR.

Conclusion

The timings of AP and AR are tied to overweight in middle childhood. Prevention strategies are suggested to move forward to control late AP and early AR.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03190-9.

Parents' perception of health promotion: What do parents think of a healthy lifestyle in parenting and the impact of the school environment? A qualitative research in the Netherlands

PURPOSE

This study aimed at gaining insight into parents' perceptions towards health behaviour in parenting and the impact of the school environment. Healthcare professionals experience barriers to discuss health behaviour in families where levels of overweight and obesity are elevated. There is a need to understand parents' perception and perceived significance of health behaviour.

DESIGN AND METHODS

Sixty-three semi-structured interviews were conducted with parents of children from three primary schools located in two different neighbourhoods in Zwolle, the Netherlands. Parents were asked to formulate their top three priority goals in parenting, additionally supplemented with 15 predetermined goals, including a health behaviour related goal. Parents ranked the goals in order of importance and gave an explanation. Finally, parents shared their opinions regarding the school environment in promoting health behaviour, according to the EnrG framework.

RESULTS

In 8 out of 63 interviews, health was reported in the top three self-formulated goals. Other goals considered important were happiness and being respectful to others. When health was ranked as less important in parenting, routine of health behaviour, own beliefs and religion were given as explanations. The physical school environment and teachers were mentioned as important factors in promoting health behaviour.

CONCLUSIONS

Parents indicate health behaviour as a key-element in parenting, even when health behaviour is not considered as the most important priority.

PRACTICE IMPLICATIONS

Since school is perceived as a logical and powerful environment, healthcare professionals should collaborate with school staff to empower their own, teachers' and parents' roles to address health promotion.

Skin and obesity in childhood: an update

<abstract> <p>Overweight and obesity have grown in children in the last decades and are now an epidemic, leading to significant public health issues in developed and underdeveloped nations. Obese children have a higher prevalence of skin lesions than normal weight children. The present study is an updated-on state of the art of studies describing the association between childhood obesity and related skin lesions. The most frequent obesity-associated dermatological complications in children are acanthosis nigricans and acrochordons, atopic dermatitis, skin infections, and endocrinological changes including hyperinsulinism and hyperandrogenism. Other common skin manifestations associated with obesity are striae distensae and plantar hyperkeratosis. Although the causes of the majority of the skin lesions associated with obesity are not known, the larger mass of adipose tissue and the secretion of peptides (cytokines, hormones, etc.) from enlarged fat cells due to obesity could lead to skin lesions. Therefore, the prevention of obesity is essential to avoid most skin-associated lesions.</p> </abstract>

Family and Lifestyle Factors Mediate the Relationship between Socioeconomic Status and Fat Mass in Children and Adolescents

Socioeconomic status (SES) is strongly associated with childhood overweight. The underlying mechanism and the role of family and lifestyle factors as potential mediators of this relationship remain, however, unclear. Cross-sectional data of 4,772 girls and boys aged 5-16 years from the Kiel Obesity Prevention Study were considered in mediation analyses. Fat mass (FM) was assessed by bioelectrical impedance analysis and converted into a percent FM SD score (FM%-SDS). SES was defined by the parental educational level, classified as low, middle, or high. Characteristics of family and lifestyle factors were obtained via validated questionnaires and considered as mediators. In 3 different age groups, the product-of-coefficients method was used to examine age-specific mediator effects on the relationship between SES and FM%-SDS (c = total effects) and their ratio to total effects, adjusted for age, sex, puberty, and nationality. The prevalence of overweight was 6.9%. In all age groups, SES was inversely associated with FM%-SDS as follows: 5-7 years, c1 = -0.11 (95% CI -0.19 to -0.03); 9-11 years, c2 = -0.21 (95% CI -0.27 to -0.14); and 13-16 years, c3 = -0.23 (95% CI -0.28 to -0.17). The relationship between SES and FM%-SDS was fully (5-7 and 9-11 years) and partly (13-16 years) mediated by similar and age-specific mediators, including parental BMI, parental smoking habits, media consumption, physical activity, and shared meals. Overall, these variables resulted in a total mediating effect of 77.8% (5-7 years), 82.4% (9-11 years), and 70.6% (13-16 years). Consistent for both sexes, the relationship between SES and FM%-SDS was therefore mediated by parental weight status, risk-related behavior within families, and children's and adolescents' lifestyle factors. Strategies for obesity prevention, which are predominantly targeted at socially disadvantaged groups, should therefore address the family environment and lifestyle factors.

Obesity: global epidemiology and pathogenesis

The prevalence of obesity has increased worldwide in the past ~50 years, reaching pandemic levels. Obesity represents a major health challenge because it substantially increases the risk of diseases such as type 2 diabetes mellitus, fatty liver disease, hypertension, myocardial infarction, stroke, dementia, osteoarthritis, obstructive sleep apnoea and several cancers, thereby contributing to a decline in both quality of life and life expectancy. Obesity is also associated with unemployment, social disadvantages and reduced socio-economic productivity, thus increasingly creating an economic burden. Thus far, obesity prevention and treatment strategies - both at the individual and population level - have not been successful in the long term. Lifestyle and behavioural interventions aimed at reducing calorie intake and increasing energy expenditure have limited effectiveness because complex and persistent hormonal, metabolic and neurochemical adaptations defend against weight loss and promote weight regain. Reducing the obesity burden requires approaches that combine individual interventions with changes in the environment and society. Therefore, a better understanding of the remarkable regional differences in obesity prevalence and trends might help to identify societal causes of obesity and provide guidance on which are the most promising intervention strategies.

The National After-School Athletics Program Participation as a Tool to Reduce the Risk of Obesity in Adolescents after One Year of Intervention: A Nationwide Study

Regular exercise during school hours is encouraged; however many children and adolescents fail to meet the recommendations during this time. Extracurricular activities may be a more appealing way for youth to achieve guidelines, and it is recommended that they attend two sessions each week. The aim of the study was to assess the influence of participation in a national physical activity program accompanied by nutritional education for trainers on the risk of obesity and body composition in a nationwide sample of boys and girls, after one year of intervention. The #goathletics Study was conducted in a group of 1014 adolescents aged 12⁻13: 507 individuals for the Athletics for All program (210 boys, 297 girls) and 507 pair-matched individuals not participating in any physical activity program (matching including: gender, age, city of residence). The body mass (kg), Body Mass Index (BMI) (kg/m²), waist circumference (WC) (cm), waist-to-height ratio (WHtR) (-) and body composition (%) (measured using bioelectrical impedance method) were compared in a gender-related sub-groups using t-Student test (for parametric distributions) or Mann-Whitney U test (for nonparametric distributions) and chi² test (for the share of sub-groups). After one year of intervention, lower body mass percentile, BMI percentile, WC, WHtR and fat mass share, higher muscle mass share, as well as lower frequency of overweight/obesity and abdominal fat distribution were observed both for boys and girls participating in the physical activity intervention compared to the pair-matched controls. The after-school physical activity program accompanied by nutritional education for trainers may be a highly effective method for reducing the risk of obesity both for boys and girls, as regular participation is ensured.

The relationship between MMP9 and ADRA2A gene polymorphisms and mothers-newborns' nutritional status: an exploratory path model (STROBE compliant article)

BACKGROUND

The aim of this study was to evaluate the direct effects of matrix metalloproteinase (MMP9 rs17577, MMP9 rs17576) and alfa 2 adrenergic receptor (ADRA2A rs553668) gene polymorphisms investigated in mothers and their newborns on maternal weight gain (MWG) during pregnancy and the newborn's birth weight (BW), taking into account the presence of other related factors.

METHODS

We performed a cross-sectional study in 197 mother-newborn pairs in an Obstetrics Gynecology Clinic, in order to evaluate the demographic and anthropometric parameters, and gene polymorphism.

RESULTS

BW was positively correlated with maternal age (p = 0.021) and the educational level (p = 0.002), and negatively correlated with smoking status in pregnant women (p < 0.001). The MMP9 rs17577 variant genotypes in mothers led to a lower BW (p = 0.049). The mothers with a variant genotype of ADRA2A rs553668 gene polymorphism had newborns with a higher BW (p = 0.030). MWG and gestational age (GesAge) influenced BW (p < 0.05). We noticed that newborns' variant genotype of MMP9 rs17577 was related to a significant increase in BW (p = 0.010), while the newborns who carried the variant genotype of MMP9 rs17576 expressed a negative correlation, decreasing the BW (p = 0.032).

CONCLUSION

Our study emphasizes the role of MMP9 rs17577, MMP9 rs17576, and ADRA2A rs553668 SNPs in BW determinism.

Prevalence and sociodemographic correlates of overweight and obesity in a large Pan-European cohort of preschool children and their families: the ToyBox study

OBJECTIVES

Health inequalities are observed among different regions and socioeconomic groups. The present study aimed to record the prevalence of overweight and obesityamong preschoolers across six European countries in relation to sociodemographic and family factors.

METHODS

A total of 7554 preschool-aged children and their parents participated in the ToyBox-study. Children's weight and height were measured and parents self-reported their weight, height, and family sociodemographic data using questionnaires. Data were obtained in May and June 2012.

RESULTS

The prevalence of overweight and obesity ranged from 10.0% in Germany to 20.6% in Greece and was found to be higher in children from low socioeconomic status (SES) families as well as children with two overweight or obese parents. Children from low-SES families and children with overweight or obese parents were more likely to be overweight or obese compared with their peers from medium- or high-SES families or those with normal-weight parents, respectively.

CONCLUSIONS

In a large sample of European preschoolers, the prevalence of overweight and obesity was found to be higher in Southern and Eastern European countries compared with Central and Northern European countries. Higher prevalence was recorded among low-SES families and in children with overweight or obese parents, which indicates that these areas and vulnerable groups need to be prioritized to close the gap in health and social inequalities and provide more effective prevention of early childhood obesity.

The role of TGF-β1 869 T > C and PPAR γ2 34 C > G polymorphisms, fat mass, and anthropometric characteristics in predicting childhood obesity at birth: A cross-sectional study according the parental characteristics and newborn's risk for child obesity (the newborns obesity's risk) NOR study

This study proposed to establish a correlation between the risk score for child obesity and anthropometric, genetic, and bioimpedance characteristics in mothers and newborns, and to assess the discriminant ability for anthropometric parameters to classify over-fatness (defined by bioimpedance body fatness %) in pregnant women.We performed a cross-sectional study on 388 couples (mother and father) and their newborns admitted in a Tertiary Hospital from Romania. The measured parameters for mothers and their newborns were risk percentage for child obesity, anthropometric characteristics (mid-upper arm circumference [MUAC], tricipital skinfold thickness [TST] of mother and newborn), genetic polymorphisms (human peroxisome proliferator-activated receptor γ [PPARγ2] 34 C > G and transforming growth factor-beta 1 [TGF-β1] 869 T > C gene polymorphisms in both mothers and newborns), and mother's bioimpedance characteristics (fat mass [FM] %).The obesity risk score according to standard predictable Northern Finland Birth Cohort equation was in our study 4.07%. We found a monotone positive significant correlation between the newborn's risk of childhood obesity and the mother's TST (P = 0.01), as well as a tendency toward statistical significance concerning correlation with mother's MUAC (P = 0.053), without any correlations with the mothers' bioimpedance parameters and also a positive correlation between the newborn's risk of childhood obesity and the newborn's anthropometrical characteristics like body mass index (BMI), MUAC, and TST (P < 0.001). We observed that the calculated newborn's risk percentage for child obesity was greater for the variant allele of the TGF-β1 869 T > C polymorphism and also for the wild-type C allele of the PPARγ2 34 C > G gene polymorphism. Our study indicated that the best predictors for over-fatness are BMI and MUAC (P = 0.01 < 0.02 and P = 0.019 < 0.02, respectively).

Associations between Sugar Intake from Different Food Sources and Adiposity or Cardio-Metabolic Risk in Childhood and Adolescence: The Korean Child-Adolescent Cohort Study

The increasing prevalence of childhood obesity is a serious public health problem associated with co-morbidities in adulthood, as well as childhood. This study was conducted to identify associations between total sugar intake and sugar intake from different foods (fruit, milk, and sugar-sweetened beverages (SSBs)), and adiposity and continuous metabolic syndrome scores (cMetS) among Korean children and adolescents using cohort data. The study subjects were children (n = 770) who participated in the 4th year (2008) of the Korean Child–Adolescent Cohort Study (KoCAS). Dietary intake data were collected via three-day 24-h food records, and sugar intake was calculated for the total sugar content of foods using our database compiled from various sources. Anthropometric measurements, assessments of body composition, and blood sample analysis were performed at baseline and at follow-up four years later. The cMetS was calculated based on waist circumference, triglycerides, high-density lipoprotein cholesterol, glucose, and mean arterial blood pressure. According to multiple linear regression analysis, there were no significant associations between total sugar intake and adiposity and cMetS. However, higher intake of fruit sugar at baseline was significantly associated with lower body mass index (BMI) z-scores and body fat percentages at baseline (β = −0.10, p = 0.02 and β = −0.78, p < 0.01, respectively). At follow-up, sugar intake from fruit at baseline was still negatively associated with the above outcomes, but only the relationship with BMI z-scores retained statistical significance (β = −0.08, p < 0.05). There was a significant positive relationship between consumption of sugar from SSBs and cMetS at baseline (β = 0.04, p = 0.02), but that relationship was not observed at follow-up (p = 0.83). Differences in consumption sugars from fruit and SSBs might play an important role in the risk of adiposity and metabolic disease in children and adolescents. Our results suggest that strategies for reducing sugar intake need to target particular food groups. Consequently, this information could be of value to obesity- and metabolic disease-prevention strategies.

Maternal post-natal tobacco use and current parental tobacco use is associated with higher body mass index in children and adolescents: an international cross-sectional study

BACKGROUND

We investigated whether maternal smoking in the first year of life or any current parental smoking is associated with childhood or adolescent body mass index (BMI).

METHODS

Secondary analysis of data from a multi-centre, multi-country, cross-sectional study (ISAAC Phase Three). Parents/guardians of children aged 6-7 years completed questionnaires about their children's current height and weight, whether their mother smoked in the first year of the child's life and current smoking habits of both parents. Adolescents aged 13-14 years completed questionnaires about their height, weight and current parental smoking habits. A general linear mixed model was used to determine the association between BMI and parental smoking.

RESULTS

77,192 children (18 countries) and 194 727 adolescents (35 countries) were included. The BMI of children exposed to maternal smoking during their first year of life was 0.11 kg/m(2) greater than those who were not (P = 0.0033). The BMI of children of currently smoking parents was greater than those with non-smoking parents (maternal smoking: +0.08 kg/m(2) (P = 0.0131), paternal smoking: +0.10 kg/m(2) (P < 0.0001)). The BMI of female adolescents exposed to maternal or paternal smoking was 0.23 kg/m(2) and 0.09 kg/m(2) greater respectively than those who were not exposed (P < 0.0001). The BMI of male adolescents was greater with maternal smoking exposure, but not paternal smoking (0.19 kg/m(2), P < 0.0001 and 0.03 kg/m(2), P = 0.14 respectively).

CONCLUSION

Parental smoking is associated with higher BMI values in children and adolescents. Whether this is due to a direct effect of parental smoking or to confounding cannot be established from this observational study.

Socioeconomic position and childhood-adolescent weight status in rich countries: a systematic review, 1990-2013

Background

Childhood obesity is a major problem in rich countries due to its high prevalence and its harmful health consequences. An exploratory analysis conducted in the PubMed database highlighted that the number of papers published on the relationship between socioeconomic position (SEP) and childhood-adolescent weight status had risen substantially with respect to an earlier review which had covered the period 1990–2005.

Methods

To describe the findings on the relationship between SEP and childhood-adolescent weight status in papers published in rich countries from 1990 through 2013, studies were identified in the following databases: PubMed; Web of Knowledge (WOK); PsycINFO; Global Health; and Embase. We included observational studies from the 27 richest OECD countries, which covered study populations aged 0 to 21 years, and used parental education, income and/or occupation as family SEP indicators. A total of 158 papers met the inclusion criteria and reported 134 bivariable and 90 multivariable analyses.

Results

Examination of the results yielded by the bivariable analyses showed that 60.4 % of studies found an inverse relationship, 18.7 % of studies did not found relationship, and 20.9 % of studies found a relationship that varied depending on another variable, such as age, sex or ethnic group; the corresponding percentages in the multivariable analyses were 51.1, 20.0 and 27.8 %, respectively. Furthermore, 1.1 % found a positive relationship.

Conclusion

The relationship between SEP and childhood-adolescent weight status in rich countries is predominantly inverse and the positive relationship almost has disappeared. The SEP indicator that yields the highest proportion of inverse relationships is parents’ education. The proportion of inverse relationships is higher when the weight status is reported by parents instead using objective measurements.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-015-0443-3) contains supplementary material, which is available to authorized users.

Longitudinal changes in adiposity during adolescence: a population-based cohort

OBJECTIVE

We aimed to assess the trends in body mass index (BMI) and body fat percentage (BF%) from the age of 13 to 17 years and to evaluate how sociodemographic and behavioural characteristics at the age of 13  impact changes in BMI and BF%.

SETTING

Porto, Portugal.

PARTICIPANTS

We evaluated 1451 adolescents in a community-based cohort.

OUTCOME MEASURES

BMI z-scores were calculated according to CDC references. BF% was assessed by bioelectrical impedance. Variables with a significant effect in adiposity changes were identified through linear regression models. In girls, estimates were controlled for duration of follow-up, parental education, baseline BMI z-score, age at menarche and the interaction term baseline BMI z-score×age at menarche; in boys, adjustments were performed for duration of follow-up, parental education, baseline BMI z-score and the interaction term baseline BMI z-score×duration of follow-up.

RESULTS

On average, BMI z-score decreased from the age of 13 to 17 years (mean difference -0.20, 95% CI -0.23 to -0.16 among girls and -0.15, 95% CI -0.19 to -0.11 among boys). Accordingly, 12.4% of girls and 13% of boys moved to a lower BMI category and 2.2% of girls and 5.5% of boys to a higher category. There were sex differences in the significant determinants of adiposity trends. Among girls, BMI z-score significantly decreased with baseline BMI z-score (β=-0.163, 95% CI -0.204 to -0.122) and significantly increased with age at menarche (β=0.078, 95% CI 0.050 to 0.107). Results were similar for BF%. Among boys, BMI z-score significantly increased with higher parental BMI, and BF% decreased among those who wished to look larger at the age of 13 (β=-1.367, 95% CI -2.174 to -0.560), compared with those who were satisfied with their image.

CONCLUSIONS

In adolescents, ageing resulted in a decrease in BMI z-scores and BF%. BMI and BF% at the age of 13 were the major determinants of the observed trends. Our results suggest that adolescence is a possible specific time window for intervention.

Fatores associados ao excesso de peso em crianças brasileiras menores de cinco anos

O objetivo do estudo foi identificar os fatores associados ao excesso de peso em crianças brasileiras menores de cinco anos. Foram utilizados dados da Pesquisa Nacional de Demografia e Saúde (PNDS) de 2006, um estudo transversal de base domiciliar. O diagnóstico do excesso de peso baseou-se no índice peso-para-altura superior a 2 escores z acima da mediana do padrão antropométrico da Organização Mundial de Saúde - 2006. A população estudada constituiu-se de 4.388 crianças. A prevalência de excesso de peso nas crianças foi descrita segundo variáveis socioeconômicas, demográficas, antropométricas e comportamentais. Foram realizadas análises bruta e ajustada através da Regressão de Poisson e todas foram estratificadas pelo sexo da criança. A prevalência de excesso de peso foi de 6,6%. Após análise ajustada, o índice de massa corporal materno e o peso ao nascer foram associados ao excesso de peso. Além disso, o excesso de peso mostrou-se associado ao tempo de amamentação exclusiva, nos meninos e ao nível socioeconômico e situação conjugal, nas meninas. Enfatiza-se a necessidade da implementação de políticas públicas que atuem, o mais precocemente possível, nos principais determinantes do excesso de peso.

[Longitudinal data of the Kiel Obesity Prevention Study (KOPS)]

The Kiel Obesity Prevention Study (KOPS) has been performed since 1996. Examinations were performed at age 6, 10 and 14 years. In addition, birth weight as well as height and weight at age 2 years were collected retrospectively. For the study 4,997, 1,671 and 748 children were recruited at baseline (at age 6 years) as well as at 4 and 8-year follow-up, respectively. In this paper we will analyze and discuss (i) the important time period for preventive measures, (ii) effect sizes needed for successful interventions and (iii) suitable approaches for preventive measures. The main results were: (i) at age 6 years persistence of overweight was 69% while at younger ages persistence was 21% only. Thus, school entry was shown to be an important period for preventive measures. (ii) Interventions have to reduce energy balance by 140 kcal/day to prevent overweight (e.g. a reduction of energy intake). (iii) Prevention programs should involve the family and focus on increasing physical activity.

Estimation of newborn risk for child or adolescent obesity: lessons from longitudinal birth cohorts

OBJECTIVES

Prevention of obesity should start as early as possible after birth. We aimed to build clinically useful equations estimating the risk of later obesity in newborns, as a first step towards focused early prevention against the global obesity epidemic.

METHODS

We analyzed the lifetime Northern Finland Birth Cohort 1986 (NFBC1986) (N = 4,032) to draw predictive equations for childhood and adolescent obesity from traditional risk factors (parental BMI, birth weight, maternal gestational weight gain, behaviour and social indicators), and a genetic score built from 39 BMI/obesity-associated polymorphisms. We performed validation analyses in a retrospective cohort of 1,503 Italian children and in a prospective cohort of 1,032 U.S. children.

RESULTS

In the NFBC1986, the cumulative accuracy of traditional risk factors predicting childhood obesity, adolescent obesity, and childhood obesity persistent into adolescence was good: AUROC = 0·78[0·74-0.82], 0·75[0·71-0·79] and 0·85[0·80-0·90] respectively (all p<0·001). Adding the genetic score produced discrimination improvements ≤1%. The NFBC1986 equation for childhood obesity remained acceptably accurate when applied to the Italian and the U.S. cohort (AUROC = 0·70[0·63-0·77] and 0·73[0·67-0·80] respectively) and the two additional equations for childhood obesity newly drawn from the Italian and the U.S. datasets showed good accuracy in respective cohorts (AUROC = 0·74[0·69-0·79] and 0·79[0·73-0·84]) (all p<0·001). The three equations for childhood obesity were converted into simple Excel risk calculators for potential clinical use.

CONCLUSION

This study provides the first example of handy tools for predicting childhood obesity in newborns by means of easily recorded information, while it shows that currently known genetic variants have very little usefulness for such prediction.

Determinants of childhood adiposity: evidence from the Australian LOOK study

BACKGROUND

To contribute to the current debate as to the relative influences of dietary intake and physical activity on the development of adiposity in community-based children.

METHODS

Participants were 734 boys and girls measured at age 8, 10 and 12 years for percent body fat (dual emission x-ray absorptiometry), physical activity (pedometers, accelerometers); and dietary intake (1 and 2-day records), with assessments of pubertal development and socioeconomic status.

RESULTS

Cross-sectional relationships revealed that boys and girls with higher percent body fat were less physically active, both in terms of steps per day and moderate and vigorous physical activity (both sexes p<0.001 for both measures). However, fatter children did not consume more energy, fat, carbohydrate or sugar; boys with higher percent body fat actually consumed less carbohydrate (p = 0.01) and energy (p = 0.05). Longitudinal analysis (combined data from both sexes) was weaker, but supported the cross-sectional findings, showing that children who reduced their PA over the four years increased their percent body fat (p = 0.04). Relationships in the 8 year-olds and also in the leanest quartile of all children, where adiposity-related underreporting was unlikely, were consistent with those of the whole group, indicating that underreporting did not influence our findings.

CONCLUSIONS

These data provide support for the premise that physical activity is the main source of variation in the percent body fat of healthy community-based Australian children. General community strategies involving dietary intake and physical activity to combat childhood obesity may benefit by making physical activity the foremost focus of attention.

Attributable risks for childhood overweight: evidence for limited effectiveness of prevention

OBJECTIVE

Calculation of attributable risks (ARs) of childhood overweight to estimate effectiveness of prevention strategies.

METHODS

We used pooled data of 4 population-based German studies including 34240 children and adolescents aged 3 to 18 years to calculate the impact of familial, social, "early life", and lifestyle factors on overweight. ARs (joint for all determinants as well as partial risks) were calculated.

RESULTS

The prevalence of childhood overweight was 13.4%. Successfully tackling all determinants can reduce overweight by 77.7% (ie, from 13.4% to 3.0%; = joint AR) with partial effects of treating parental overweight (42.5%); improving social status (14.3%); reducing media time to <1 hour per day (11.4%); and not smoking during pregnancy, low weight gain during pregnancy, and breastfeeding (together 9.5%), respectively. Improving all preventable risk factors (ie, early life factors and lifestyle) the effect is 9.2%. Media time has the strongest effect.

CONCLUSIONS

The determinants identified explained 78% of the prevalence of overweight. Taking into account the partial ARs, the effectiveness of lifestyle interventions to prevent overweight in children is limited. Our data argue in favor of interventions aimed at families and social environments, with a major focus on promoting a lower screen time and computer use in children.

Critical review: vegetables and fruit in the prevention of chronic diseases

BACKGROUND

Vegetables and fruit provide a significant part of human nutrition, as they are important sources of nutrients, dietary fibre, and phytochemicals. However, it is uncertain whether the risk of certain chronic diseases can be reduced by increased consumption of vegetables or fruit by the general public, and what strength of evidence has to be allocated to such an association.

METHODS

Therefore, a comprehensive analysis of the studies available in the literature and the respective study results has been performed and evaluated regarding obesity, type 2 diabetes mellitus, hypertension, coronary heart disease (CHD), stroke, cancer, chronic inflammatory bowel disease (IBD), rheumatoid arthritis (RA), chronic obstructive pulmonary disease (COPD), asthma, osteoporosis, eye diseases, and dementia. For judgement, the strength of evidence for a risk association, the level of evidence, and the number of studies were considered, the quality of the studies and their estimated relevance based on study design and size.

RESULTS

For hypertension, CHD, and stroke, there is convincing evidence that increasing the consumption of vegetables and fruit reduces the risk of disease. There is probable evidence that the risk of cancer in general is inversely associated with the consumption of vegetables and fruit. In addition, there is possible evidence that an increased consumption of vegetables and fruit may prevent body weight gain. As overweight is the most important risk factor for type 2 diabetes mellitus, an increased consumption of vegetables and fruit therefore might indirectly reduces the incidence of type 2 diabetes mellitus. Independent of overweight, there is probable evidence that there is no influence of increased consumption on the risk of type 2 diabetes mellitus. There is possible evidence that increasing the consumption of vegetables and fruit lowers the risk of certain eye diseases, dementia and the risk of osteoporosis. Likewise, current data on asthma, COPD, and RA indicate that an increase in vegetable and fruit consumption may contribute to the prevention of these diseases. For IBD, glaucoma, and diabetic retinopathy, there was insufficient evidence regarding an association with the consumption of vegetables and fruit.

CONCLUSIONS

This critical review on the associations between the intake of vegetables and fruit and the risk of several chronic diseases shows that a high daily intake of these foods promotes health. Therefore, from a scientific point of view, national campaigns to increase vegetable and fruit consumption are justified. The promotion of vegetable and fruit consumption by nutrition and health policies is a preferable strategy to decrease the burden of several chronic diseases in Western societies.

Overweight and lifestyle among 13–15 year olds: A cross-sectional study in northern Sweden

Aim: To increase knowledge of self-rated health and lifestyle in relation to overweight/obesity among 13–15 year olds in northern Sweden. Methods: All 6768 13–15 year olds in nine out of 15 municipalities in Västerbotten County were asked to complete a cross-sectional school-based on-line survey in 2007. Eighty-two per cent participated in the study. Responses were considered reliable for 74% of the participants (2517 boys/2470 girls). The survey addressed demography, self-rated health, self-reported weight, height, and lifestyle characteristics. Simple and multiple logistic regression analyses were used. Results: Overweight/obesity (ISO body mass index ≥25 kg/m2) was more prevalent among boys (20%) than girls (11%), but more girls (19%) than boys (9%) reported fair or bad health. Overweight/obese boys and girls were more often physically inactive. For the boys, overweight/obesity was also associated with skipping breakfast, insufficient tooth brushing, and using snuff. For the girls, overweight/obesity was also associated with living with one parent and more television watching. Boys reported healthier habits concerning sleep duration, physical activity, eating breakfast, and smoking compared to the girls. On the other hand, girls reported better dietary and tooth brushing habits. Conclusions: This study uncovered two alarming findings: a fifth of the boys were overweight/obese and a fifth of the girls reported fair or bad health. Girls living with a single parent and boys and girls with unhealthy lifestyles were more likely to be overweight. Our findings emphasise the need for developing and implementing effective health promotion strategies for school-aged children to prevent an overweight and obesity epidemic that could continue into adulthood.

Reasons for (non)participating in a telephone-based intervention program for families with overweight children

Objective

Willingness to participate in obesity prevention programs is low; underlying reasons are poorly understood. We evaluated reasons for (non)participating in a novel telephone-based obesity prevention program for overweight children and their families.

Method

Overweight children and adolescents (BMI>90^th percentile) aged 3.5–17.4 years were screened via the CrescNet database, a representative cohort of German children, and program participation (repetitive computer aided telephone counseling) was offered by their local pediatrician. Identical questionnaires to collect baseline data on anthropometrics, lifestyle, eating habits, sociodemographic and psychosocial parameters were analyzed from 433 families (241 participants, 192 nonparticipants). Univariate analyses and binary logistic regression were used to identify factors associated with nonparticipation.

Results

The number of overweight children (BMI>90^th percentile) was higher in nonparticipants than participants (62% vs. 41.1%,p<0.001), whereas the number of obese children (BMI>97^th percentile) was higher in participants (58.9% vs.38%,p<0.001). Participating girls were younger than boys (8.8 vs.10.4 years, p<0.001). 87.3% and 40% of participants, but only 72.2% and 24.7% of nonparticipants, respectively, reported to have regular breakfasts (p = 0.008) and 5 regular daily meals (p = 0.003). Nonparticipants had a lower household-net-income (p<0.001), but higher subjective physical wellbeing than participants (p = 0.018) and believed that changes in lifestyle can be made easily (p = 0.05).

Conclusion

An important reason for nonparticipation was non-awareness of their child's weight status by parents. Nonparticipants, who were often low-income families, believed that they already perform a healthy lifestyle and had a higher subjective wellbeing. We hypothesize that even a low-threshold intervention program does not reach the families who really need it.

Commentary on "estimation of newborn risk for child or adolescent obesity: lessons from longitudinal birth cohorts"

Childhood obesity is an increasingly prevalent problem, associated with obesity later in life, and a sequalae of health problems such as metabolic syndrome and an increased risk of coronary heart disease. Poor nutrition and a lack of physical activity are said to be causes of obesity development, with genetic factors and heritability also implicated. However, there are established, identifiable risk factors associated with the future development of obesity, both in childhood, and adolescence. These include parental weight before pregnancy, gestational weight gain, pre-pregnancy maternal smoking, as well as numerous socioeconomic factors.(1-4) Studies have also shown that once obese, children can find it very difficult to lose the excess weight,(5) with long-term management methods having shown poor efficacy.(5) Therefore, preventative strategies are becoming a high priority to battle the ever-increasing epidemic of childhood obesity. This study by Morandi et al.(6) is the first longitudinal study to analyse the predictive properties of early life risk factors for obesity, and propose a subsequent predictive algorithm to identify newborns most at risk of becoming obese in childhood and adolescence. Morandi et al.'s study aimed to develop a clinically useful formula, which could be used to identify the risk of future obesity in newborns, thereby enabling more efficient implementation of prevention strategies.(6) The lifetime Northern Finland Birth Cohort 1986 (NFBC 1986) was used to form predictive equations for both childhood and adolescent obesity, based on established risk factors: parental BMI, birth weight, maternal gestational weight gain, and socioeconomic factors. A genetic score was also created based on 39 BMI/obesity-associated polymorphisms. Validation studies were performed on both a retrospective cohort of children from Veneto, Italy, and a prospective cohort of children from Massachusetts, USA.

Incidence of obesity during childhood and adolescence in a large contemporary cohort

BACKGROUND AND AIMS

Timing of obesity development during childhood and adolescence is unclear, hindering preventive strategies. The primary aim of the present study was to quantify the incidence of overweight and obesity throughout childhood and adolescence in a large contemporary cohort of English children (the Avon Longitudinal Study of Parents and Children, ALSPAC; children born 1991-1992). A secondary aim was to examine the persistence of overweight and obesity.

METHODS

Longitudinal data on weight and height were collected annually from age 7-15 years in the entire ALSPAC cohort (n=4283), and from 3 to 15 years in a randomly selected subsample of the cohort (n=549; 'Children in Focus' CiF). Incidence of overweight and obesity (BMI (Body mass index) at or above the 85th and 95th centiles relative to U.K. reference data) was calculated. Risk ratios (RR) for overweight and obesity at 15 years based on weight status at 3, 7, and 11 years were also calculated.

RESULTS

In the entire cohort, four-year incidence of obesity was higher between ages 7 and 11 years than between 11 and 15 years (5.0% vs. 1.4% respectively). In the CiF sub-sample, four-year incidence of obesity was also highest during mid-childhood (age 7-11years, 6.7%), slightly lower during early childhood (3-7 years, 5.1%) and lowest during adolescence (11-15 years 1.6%). Overweight and obesity at all ages had a strong tendency to persist to age 15 years as indicated by risk ratios (95% CI (Confidence interval)) for overweight and obesity at 15 years from overweight and obesity (relative to healthy weight status) at 3 years (2.4, 1.8-3.1), 7 years (4.6, 3.6-5.8), and 11 years (9.3, 6.5-13.2).

CONCLUSION

Mid-late childhood (around age 7-11 years) may merit greater attention in future obesity prevention interventions.

Associations between neighbourhood characteristics, body mass index and health-related behaviours of adolescents in the Kiel Obesity Prevention Study: a multilevel analysis

BACKGROUND/OBJECTIVES

To understand determinants of overweight, several studies addressed the association between neighbourhood characteristics and adult obesity. However, little is known about the association of such characteristics with adolescents' overweight. This study aims at the influence of neighbourhood characteristics on adolescent body mass index (BMI) and lifestyle and to what extent BMI and lifestyle variation between neighbourhoods can be explained by neighbourhood characteristics.

SUBJECTS/METHODS

We used cross-sectional data from the Kiel Obesity Prevention Study collected between 2004 and 2008 in 28 different residential districts of the city of Kiel (North Germany). Anthropometric data were available for 1675 boys and 1765 girls (n=3440) aged 13-15 years, and individual lifestyle factors and sociodemographic data were included in the analysis. At the macro level, six different neighbourhood characteristics were used: unemployment rate, population density, traffic density, prevalence of energy-dense food supply, number of sports fields and parks, and crime rate. To test our main hypothesis, linear and logistic multilevel regression analyses were performed to predict BMI and lifestyle factors in individuals nested in neighbourhoods.

RESULTS

Findings of multilevel analysis show little between-neighbourhood variations in BMI and health-related behaviours. In all, 2% of BMI variation, 4% of media time variation and 3% of variation in snacking behaviour could be attributed to differences in neighbourhoods.

CONCLUSIONS

Environmental factors are significantly associated with adolescent BMI and health-related behaviour; however, their total effect is small. Owing to these results, recommendations for structural policy measures as part of prevention of overweight in adolescents must be made cautiously.

Clustering of lifestyle factors and association with overweight in adolescents of the Kiel Obesity Prevention Study

OBJECTIVE

To identify lifestyle clusters in adolescents and to characterize their association with overweight and obesity.

DESIGN

Cross-sectional and longitudinal data of the Kiel Obesity Prevention Study.

SETTING

Schools in Kiel, Germany.

SUBJECTS AND METHODS

Cross-sectional data of 1894 adolescents aged 14 years and 4-year longitudinal data of a subsample of 389 children aged 10 and 14 years. Self-reported data of physical activity, modes of commuting to school, media time, nutrition, alcohol consumption and smoking were used to identify lifestyle clusters with two-step cluster analysis. Obesity indices (height, weight, waist circumference and fat mass (FM)) were measured.

RESULTS

Three lifestyle clusters were identified: a 'low activity and low-risk behaviour' cluster (cluster 1: n 740, 39·1 %); a 'high media time and high-risk behaviour' cluster (cluster 2: n 498, 26·3 %); and a 'high activity and medium-risk behaviour' cluster (cluster 3: n 656, 34·6 %). Strictly speaking, none of these clusters was considered to be markedly healthy. The prevalence of overweight and obesity tended to be lower in cluster 3 (15·9 %) than in clusters 1 (20·4 %) and 2 (20·5 %; P = 0·053). Longitudinally, 4-year changes in FM were found to be lowest in cluster 2, but the 4-year incidence rate of obesity was lowest in cluster 3.

CONCLUSIONS

Explicit healthy lifestyles do not exist, but an active lifestyle reduces the incidence of obesity. In adolescents, health promotion should take into account the diversity of lifestyles and address specific lifestyle clusters.