The effects of hypothetical behavioral interventions on the 13-year incidence of overweight/obesity in children and adolescents

BACKGROUND

In view of the high burden of childhood overweight/obesity (OW/OB), it is important to identify targets for interventions that may have the greatest effects on preventing OW/OB in early life. Using methods of causal inference, we studied the effects of sustained behavioral interventions on the long-term risk of developing OW/OB based on a large European cohort.

METHODS

Our sample comprised 10 877 children aged 2 to < 10 years at baseline who participated in the well-phenotyped IDEFICS/I.Family cohort. Children were followed from 2007/08 to 2020/21. Applying the parametric g-formula, the 13-year risk of developing OW/OB was estimated under various sustained hypothetical interventions on physical activity, screen time, dietary intake and sleep duration. Interventions imposing adherence to recommendations (e.g. maximum 2 h/day screen time) as well as interventions 'shifting' the behavior by a specified amount (e.g. decreasing screen time by 30 min/day) were compared to 'no intervention' (i.e. maintaining the usual or so-called natural behavior). Separately, the effectiveness of these interventions in vulnerable groups was assessed.

RESULTS

The 13-year risk of developing OW/OB was 30.7% under no intervention and 25.4% when multiple interventions were imposed jointly. Meeting screen time and moderate-to-vigorous physical activity (MVPA) recommendations were found to be most effective, reducing the incidence of OW/OB by -2.2 [-4.4;-0.7] and -2.1 [-3.7;-0.8] percentage points (risk difference [95% confidence interval]), respectively. Meeting sleep recommendations (-0.6 [-1.1;-0.3]) had a similar effect as increasing sleep duration by 30 min/day (-0.6 [-0.9;-0.3]). The most effective intervention in children of parents with low/medium educational level was being member in a sports club; for children of mothers with OW/OB, meeting screen time recommendations and membership in a sports club had the largest effects.

CONCLUSIONS

While the effects of single behavioral interventions sustained over 13 years were rather small, a joint intervention on multiple behaviors resulted in a relative reduction of the 13-year OW/OB risk by between 10 to 26%. Individually, meeting MVPA and screen time recommendations were most effective. Nevertheless, even under the joint intervention the absolute OW/OB risk remained at a high level of 25.4% suggesting that further strategies to better prevent OW/OB are required.

Associations between food portion sizes, insulin resistance, VO2 max and metabolic syndrome in European adolescents: The HELENA study

BACKGROUND AND AIMS

This study aims to examine the associations of food portion size (PS) with markers of insulin resistance (IR) and clustered of metabolic risk score in European adolescents.

METHODS

A total of 495 adolescents (53.5% females) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study were included. The association between PS from food groups and homeostasis model assessment of insulin resistance (HOMA-IR) index, VO2 max, and metabolic risk score was assessed by multilinear regression analysis adjusting for several confounders. Analysis of covariance (ANCOVA) was used to determine the mean differences of food PS from food groups by HOMA-IR cutoff categories by using maternal education as a covariable.

RESULTS

Larger PS from vegetables in both gender and milk, yoghurt, and milk beverages in males were associated with higher VO2 max, while larger PS from margarines and vegetable oils were associated with lower VO2 max (p < 0.05). Males who consumed larger PS from fish and fish products; meat substitutes, nuts, and pulses; cakes, pies, and biscuits; and sugar, honey, jams, and chocolate have a higher metabolic risk score (p < 0.05). Males with lower HOMA-IR cutoff values consumed larger PS from vegetables, milk, yoghurt, and milk beverages (p < 0.05). Females with lower HOMA-IR cutoff values consumed larger PS from breakfast cereals, while those with higher HOMA-IR cutoff values consumed larger PS from butter and animal fats (p = 0.018).

CONCLUSION

The results show that larger PS from dairy products, cereals, and high energy dense foods are a significant determinant of IR and VO2 max, and larger PS from food with higher content of sugar were associated with higher metabolic risk score.

Cross-sectional and longitudinal associations between sleep duration, sleep quality, and bone stiffness in European children and adolescents

In this large perspective cohort among European children and adolescents, we observed that daytime napping was positively associated with bone stiffness, while short or long sleep duration combined with poor sleep quality was associated with less bone stiffness. Our findings are important for obtaining optimal bone stiffness in childhood.

INTRODUCTION

To examine the cross-sectional and longitudinal associations between sleep duration, sleep quality, and bone stiffness index (SI) in European children and adolescents.

METHODS

Four thousand eight hundred seventy-one children aged 2-11 years from the IDEFICS study and 861 children aged 6-15 years from the subsequent I.Family study were included. Sleep duration (i.e., nocturnal sleep and daytime napping) and sleep quality (i.e., irregularly bedtime routine, have difficulty falling asleep and trouble getting up in the morning) were reported by self-administrated questionnaires. Nocturnal sleep duration was converted into age-specific z-scores, and total sleep duration was classified into short, adequate, and long based on the National Sleep Recommendation. Calcaneal SI of both feet were measured using quantitative ultrasound. Linear mixed-effects models with country as a random effect were used, with adjustments for sex, age, pubertal status, family socioeconomic status, physical activity, screen time, body mass index, and daylight duration.

RESULTS

Nocturnal sleep duration z-scores were positively associated with SI percentiles among participants with adequate sleep duration at baseline. Moreover, the positive association between daytime napping and SI percentiles was more pronounced in participants with adequate sleep duration at baseline, while at 4-year follow-up was more pronounced in participants with short sleep duration. In addition, extreme sleep duration at baseline predicted lower SI percentiles after 4 years in participants with poor sleep quality.

CONCLUSION

The positive associations between nocturnal sleep, daytime napping and SI depended on total sleep duration. Long-term detrimental effect of extreme sleep duration on SI only existed in individuals with poor sleep quality.

A within-sibling pair analysis of lifestyle behaviours and BMI z-score in the multi-centre I.Family study

BACKGROUND AND AIMS

By investigating differences in lifestyle behaviours and BMI in sibling pairs, family-level confounding is minimized and causal inference is improved, compared to cross-sectional studies of unrelated children. Thus, we aimed to investigate within-sibling pair differences in different lifestyle behaviours and differences in BMI z-scores in children and adolescents.

METHODS AND RESULTS

We examined three groups of sibling pairs 1) all same-sex sibling pairs with maximum 4 years age difference (n = 1209 pairs from 1072 families in 8 countries, mean age 10.7 years, standard deviation 2.4 years), 2) sibling pairs discordant for overweight (n = 262) and 3) twin pairs (n = 85). Usual dietary intake was estimated by 24-h recalls and time spent in light (LPA) and moderate-to-vigorous physical activity (MVPA) was measured by accelerometers. Screen time, sleep and dieting for weight loss were assessed by questionnaires. Within all 3 groups of sibling pairs, more time in MVPA was associated with lower BMI z-score. Higher energy intake was associated with higher BMI z-score within twin pairs and within all sibling pairs who were not currently dieting for weight loss. Regarding LPA, screen time or sleep duration, no or inconsistent associations were observed for the three groups of sibling pairs.

CONCLUSIONS

MVPA and energy intake were associated with BMI differences within sibling and twin pairs growing up in the same home, thus independent of family-level confounding factors. Future studies should explore whether genetic variants regulating appetite or energy expenditure behaviours account for weight differences in sibling pairs.

Relationship between sleep duration and childhood obesity: Systematic review including the potential underlying mechanisms

AIM

The prevalence of obesity is continually increasing worldwide. Determining risk factors for obesity may facilitate effective preventive programs. The present review focuses on sleep duration as a potential risk factor for childhood obesity. The aim is to summarize the evidence on the association of sleep duration and obesity and to discuss the underlying potential physiological and/or pathophysiological mechanisms.

DATA SYNTHESIS

The Ovid MEDLINE, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for papers using text words with appropriate truncation and relevant indexing terms. All studies objectively measuring sleep duration and investigating the association between sleep duration and obesity or factors (lifestyle and hormonal) possibly associated with obesity were included, without making restrictions based on study design or language. Data from eligible studies were extracted in tabular form and summarized narratively. After removing duplicates, 3540 articles were obtained. Finally, 33 studies (including 3 randomized controlled trials and 30 observational studies) were included in the review.

CONCLUSION

Sleep duration seems to influence weight gain in children, however, the underlying explanatory mechanisms are still uncertain. In our review only the link between short sleep duration and the development of insulin resistance, sedentarism and unhealthy dietary patterns could be verified, while the role of other mediators, such as physical activity, screen time, change in ghrelin and leptin levels, remained uncertain. There are numerous evidence gaps. To answer the remaining questions, there is a need for studies meeting high methodological standards and including a large number of children.

Actual and perceived weight status and its association with slimming and energy-balance related behaviours in 10- to 12-year-old European children: the ENERGY-project

BACKGROUND

Both parents' and children's perception of children's weight status may be important predictors of slimming and energy-balance related behaviours, independent of children's actual weight status.

OBJECTIVES

We examined the cross-sectional association of children's self-reported slimming and energy-balance related behaviours with children's (i) actual, (ii) self-perceived and (iii) parent-perceived weight status.

METHODS

Data of 10- to 12-year-old European children and their parents were used. Multilevel logistic and linear regression analyses were performed, adjusting for age, gender, parental weight controlling behaviours, education, marital status and ethnicity.

RESULTS

Independent of their actual weight status, a higher proportion of children reported slimming when they or their parents perceived them as too fat. Children's self-perceived weight status was more strongly associated with slimming than their parents' perception or their actual weight status. Moreover, children who perceive themselves as overweight reported less physical activity and more screen time. Children whose parents perceive them as overweight reported less physical activity.

CONCLUSIONS

Children's own perception of their weight status appears to be more important for their self-reported slimming than their actual or their parent's perceptions of their weight status. Additionally, children's self-perceived weight status seems important in engaging more physical activity and reduces screen time.

Folate and vitamin B12 concentrations are associated with plasma DHA and EPA fatty acids in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study

This study aimed to examine the association between vitamin B6, folate and vitamin B12 biomarkers and plasma fatty acids in European adolescents. A subsample from the Healthy Lifestyle in Europe by Nutrition in Adolescence study with valid data on B-vitamins and fatty acid blood parameters, and all the other covariates used in the analyses such as BMI, Diet Quality Index, education of the mother and physical activity assessed by a questionnaire, was selected resulting in 674 cases (43 % males). B-vitamin biomarkers were measured by chromatography and immunoassay and fatty acids by enzymatic analyses. Linear mixed models elucidated the association between B-vitamins and fatty acid blood parameters (changes in fatty acid profiles according to change in 10 units of vitamin B biomarkers). DHA, EPA) and n-3 fatty acids showed positive associations with B-vitamin biomarkers, mainly with those corresponding to folate and vitamin B12. Contrarily, negative associations were found with n-6:n-3 ratio, trans-fatty acids and oleic:stearic ratio. With total homocysteine (tHcy), all the associations found with these parameters were opposite (for instance, an increase of 10 nmol/l in red blood cell folate or holotranscobalamin in females produces an increase of 15·85 µmol/l of EPA (P value <0·01), whereas an increase of 10 nmol/l of tHcy in males produces a decrease of 2·06 µmol/l of DHA (P value <0·05). Positive associations between B-vitamins and specific fatty acids might suggest underlying mechanisms between B-vitamins and CVD and it is worth the attention of public health policies.

Blood fatty acid composition in relation to allergy in children aged 2-9 years: results from the European IDEFICS study

BACKGROUND/OBJECTIVES

Blood polyunsaturated fatty acids (PUFA) are involved in allergy development, but the etiological role of n-6 and n-3 PUFA is still controversial. A European multicenter study of children (IDEFICS) provided the opportunity to explore the cross-sectional association between fatty acids (FA) and allergy.

SUBJECTS/METHODS

Blood FA levels were measured in 2600 children aged 2-9 years and were recorded as the percentage of weight of all FA detected. Logistic regression of allergy status on FA components was adjusted for age, sex, country, body mass index, family history of allergic disease, breast-feeding, and number of siblings. The results were given as odds ratios (OR) for current vs no allergy ever and an increase in FA by 1 s.d.

RESULTS

Overall, higher proportions of n-6 PUFA were associated with higher odds of allergy (OR=1.21 (1.05, 1.40)). Monounsaturated FA (MUFA) were associated with reduced risk for allergy (OR=0.75 (0.65, 0.87)), whereas saturated FA did not differ by allergy status. The strongest associations were observed in children <4 years old, with ORs of allergy given as 1.62 (1.15, 2.29) for n-3 PUFA and 0.63 (0.42, 0.95) for MUFA. With regard to individual FA, these associations were independently observed for docosapentaenoic acid (22:5 n-3) and oleic acid (18:1 n-9).

CONCLUSIONS

Both PUFA subtypes were positively associated with allergy in an age-dependent manner, whereas MUFA was associated with less allergy. The observation of high proportions of n-3 PUFA in allergic children younger than 4 years might help to understand the nature of early onset of atopic disease.

Effect of the IDEFICS multilevel obesity prevention on children's sleep duration

BACKGROUND

According to recent findings, short sleep duration is associated with overweight in children. However, primary prevention efforts aimed at achieving adequate sleep among children are scarce. Therefore, the 'Identification and prevention of Dietary-induced and lifestyle-induced health EFfects In Children and infantS' (IDEFICS) study implemented a multilevel intervention that included sleep duration as a key behavioural target. The aim of this study is to evaluate sleep duration among children participating in the IDEFICS study.

METHODS

The IDEFICS nocturnal sleep intervention was included as part of stress reduction educational messages aimed at parents and children. Sleep was assessed by a parental 24-h recall (only weekdays; n = 8,543) and by a diary (weekdays and weekends separately; n = 4,150). Mixed linear models tested the intervention effect on sleep duration change between baseline when children were 2-9.9 years of age (2007/2008) and follow-up (2009/2010). Logistic mix models were used to study the intervention effect on the presence of TV in the children's bedroom (one of the intervention messages; n = 8,668). Additionally, parents provided qualitative data regarding exposure to the intervention.

RESULTS

About 51.1% of the parents in the intervention regions reported awareness of the sleep intervention. A small intervention effect was seen on weeknight sleep duration in that the decrease in sleep duration over 2 years was smaller in the intervention (15 min) as compared with control regions (19 min) (p = 0.044). There was no overall intervention effect on weekend sleep duration or on the presence of a TV in the bedroom. A small significant time effect between baseline and follow-up was found on bedroom TV presence depending on self-reported intervention exposure (3% increase in TV presence in exposed versus 6.6% increase in non-exposed). Children without a TV in the bedroom had longer nocturnal sleep duration.

DISCUSSION

The sleep component of the intervention did not lead to clinically relevant changes in sleep duration. Future interventions aimed at young children's sleep duration could benefit from more specific and intense messaging than that found in the IDEFICS intervention. Future research should use objective measures of sleep duration as well as intermediate outcomes (sleep knowledge, sleep environment and sleep practices).

Adherence to combined lifestyle factors and their contribution to obesity in the IDEFICS study

BACKGROUND

The Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS) study investigated the aetiology of childhood obesity and developed a primary prevention programme.

METHODS

Pre-intervention adherence to key behaviours related to childhood obesity, namely water/sweetened drink, fruit/vegetable consumption, daily TV time, physical activity, family time and adequate sleep duration, was measured at baseline. Adherence to international recommendations was converted into a composite score ranging from 0 (none) to 6 (adhering to all). Data on adherence were available for 7,444 to 15,084 children aged 2-9.9 years, depending on the behaviour. By means of multi-level logistic regression models adjusted for age, sex and country, we calculated odds ratios (OR) and 95% confidence intervals (CI) to estimate the relationship between adherence to these recommendations and the risk of being overweight/obese.

RESULTS

Adherence ranged from 15.0% (physical activity) to 51.9% (TV time). As adherence increased, a lower chance of being overweight/obese was observed; adhering to only one key behaviour (score = 1) meant an OR = 0.81 (CI: 0.65-1.01) compared with non-adherence (score = 0), while adhering to more than half of the key behaviours (score ≥ 4) halved the chance for overweight/obesity (OR = 0.54, CI: 0.37-0.80). Adherence to physical activity, TV and sleep recommendations was the main driver reducing the chance of being overweight. Overweight/obese children were more likely not to adhere to at least one of the recommended behaviours (19.8%) than normal-weight/thin children (12.9%)

CONCLUSION

The selected key behaviours do not contribute equally to a reduced chance of being overweight. Future interventions may benefit most from moving more, reducing TV time and getting adequate sleep.

Differential outcome of the IDEFICS intervention in overweight versus non-overweight children: did we achieve 'primary' or 'secondary' prevention?

BACKGROUND

The aim of this study was to explore whether the IDEFICS intervention had a differential effect on 11,041 children's weight trajectories depending on their baseline body mass index status.

METHODS

Two subgroups of children are considered in the present analysis: those who were overweight or obese prior to the intervention and those who were neither overweight nor obese.

RESULTS

Among children in all eight countries who did not have prevalent overweight or obesity (OWOB) at baseline, 2 years later, there was no significant difference between intervention and control groups in risk of having developed OWOB. However, we observed a strong regional heterogeneity, which could be attributed to the presence of one distinctly outlying country, Belgium, where the intervention group had increased risk for becoming overweight. In contrast, among the sample of children with prevalent OWOB at baseline, we observed a significantly greater probability of normalized weight status after 2 years. In other words, a protective effect against persistent OWOB was observed in children in intervention regions compared with controls, which corresponded to an adjusted odds ratio of 0.76 (95% confidence interval: 0.58, 0.98).

DISCUSSION

This analysis thus provided evidence of a differential effect of the IDEFICS intervention, in which children with overweight may have benefited without having been specifically targeted. However, no overall primary preventive effect could be observed in children without initial overweight or obesity.

Impact of a community based health-promotion programme in 2- to 9-year-old children in Europe on markers of the metabolic syndrome, the IDEFICS study

INTRODUCTION

One objective of 'Identification and prevention of Dietary-and lifestyle-induced health EFfects In Children and infantS', the IDEFICS study, was to implement a community-oriented childhood obesity prevention intervention in eight European countries.

OBJECTIVE

To assess the effect of an obesity primary prevention programme on metabolic markers.

METHODS

The study had a non-randomized cluster-experimental design. In each country, children were recruited from distinct communities serving as intervention and control regions. Health examinations were done during 2007-2008 before the intervention (T0 ) and during 2009-2010 (T1 ). Children with results available from T0 and T1 on blood pressure, waist circumference and at least one blood-marker (fasting glucose, insulin, HOMA-IR, HbA1c, HDL- and LDL-cholesterol, triglycerides, C-reactive protein) were included. A metabolic syndrome (MetS) score was calculated.

RESULTS

A total of 7,406 children (age 2-9.9 years) of the 16,228 participating at T0 provided the necessary data. No effect of the intervention was seen on insulin, HOMA-IR, CRP or the MetS score. Overall fasting glucose increased less in the intervention than in the control region, a pattern driven by three of the eight countries and more pronounced in children of parents with low education. Overall, HbA1c and waist circumference increased more and blood pressure less in the intervention regions.

CONCLUSION

We observed no convincing effect of the intervention on markers of the metabolic syndrome. We identified diverse patterns of change for several markers of uncertain relation to the intervention.

Parents' evaluation of the IDEFICS intervention: an analysis focussing on socio-economic factors, child's weight status and intervention exposure

INTRODUCTION

From April 2008 to August 2010 the Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS) intervention aimed to encourage healthier diets, higher physical activity levels and lower stress levels among European children and their families. While the intervention was intended to improve children's health, we also wished to assess whether there were unwelcome aspects or negative side-effects. Therefore all parents of children who participated in the IDEFICS intervention were asked for their views on different aspects of the intervention.

METHODS

A total of 10,016 parents of children who participated in the IDEFICS survey and who were involved in the intervention were invited to complete a questionnaire on positive and negative impacts of the intervention. Responses to each of the statements were coded on a four point Likert-type scale. Demographic data were collected as part of the baseline (T0 ) and first follow-up (T1 ) surveys; intervention exposure data was also collected in the T1 follow-up survey. Anthropometric data was collected in the same surveys, and child's weight status was assessed according to Cole and Lobstein. After initial review of the univariate statistics multilevel logistic regression was conducted to analyse the influence of socio-economic factors, child's weight status and intervention exposure on parental responses.

RESULTS

In total 4,997 responses were received. Approval rates were high, and few parents reported negative effects. Parents who reported higher levels of exposure to the intervention were more likely to approve of it and were also no more likely to notice negative aspects. Less-educated and lower income parents were more likely to report that the intervention would make a lasting positive difference, but also more likely to report that the intervention had had negative effects. Parents of overweight and obese children were more likely to report negative effects - above all, that 'the intervention had made their child feel as if he/she was "fat" or "overweight." '

CONCLUSION

While the results represent a broad endorsement of the IDEFICS intervention, they also suggest the importance of vigilance concerning the psychological effects of obesity interventions on overweight and obese children.

Effects of a community-oriented obesity prevention programme on indicators of body fatness in preschool and primary school children. Main results from the IDEFICS study

BACKGROUND/OBJECTIVES

Childhood obesity is a major public health concern but evidence-based approaches to tackle this epidemic sustainably are still lacking. The Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS) study investigated the aetiology of childhood obesity and developed a primary prevention programme. Here, we report on the effects of the IDEFICS intervention on indicators of body fatness.

SUBJECTS/METHODS

The intervention modules addressed the community, school and parental level, focusing on diet, physical activity and stress-related lifestyle factors. A cohort of 16,228 children aged 2-9.9 years - about 2000 per country - was equally divided over intervention and control regions. (Participating countries were Sweden, Germany, Estonia, Hungary, Cyprus, Italy, Spain and Belgium.) We compared the prevalence of overweight/obesity and mean values of body mass index z-score, per cent body fat and waist-to-height ratio over 2 years of follow-up. Mixed models adjusting for age and socioeconomic status of the parents and with an additional random effect for country accounted for the clustered study design.

RESULTS

The prevalence of overweight and obesity increased in both the intervention and control group from 18.0% at baseline to 22.9% at follow-up in the control group and from 19.0% to 23.6% in the intervention group. The difference in changes between control and intervention was not statistically significant. For the cohort as a whole, the changes in indicators of body fatness did not show any clinically relevant differences between the intervention and control groups. Changes in favour of intervention treatment in some indicators were counterbalanced by changes in favour of the control group in some other indicators.

CONCLUSIONS

Over the 2-year-observation period, the IDEFICS primary prevention programme for childhood obesity has not been successful in reducing the prevalence of overweight and obesity nor in improving indicators of body fatness in the target population as a whole.

Effectiveness of the IDEFICS intervention on objectively measured physical activity and sedentary time in European children

BACKGROUND

This paper reports on the effectiveness of the prevention of dietary- and lifestyle-induced health effects in children and infants (IDEFICS) intervention on objectively measured physical activity (PA) and sedentary time (ST) in 2- to 9.9-year-old European boys and girls.

METHODS

The intervention was evaluated after 2 years through a non-randomized cluster-controlled trial in eight European countries (one control and one intervention community per country). All children in the intervention group received a culturally adapted childhood obesity prevention programme through the community, schools/kindergartens and family. A random sub-sample of children participating in the IDEFICS study wore an accelerometer at baseline and follow-up for at least 3 days (n = 9,184). Of this sample, 81% provided valid accelerometer data at baseline (n = 7,413; 51% boys; 6.21 ± 1.76 years; boys: 617 ± 170 cpm day(-1) ; girls 556 ± 156 cpm day(-1) ) and 3,010 children provided valid accelerometer data at baseline and during the follow-up survey 2 years later.

RESULTS

In boys and girls, no significant differences in PA and ST were found between intervention and control groups over 2 years. Strong temporal effects were found in the total sample of boys and girls: the percentage of time spent in light PA per day decreased by 4 percentage points in both boys and girls between baseline and follow-up (both: p < 0.001), while time spent in ST per day increased by 4 percentage points in both sexes over time (both: p < 0.001). Percentage of time spent in moderate-to-vigorous PA per day remained stable over time in boys and girls.

CONCLUSION

Despite the socio-ecological approach and implementation of a culturally adapted intervention in each country, no effects of the IDEFICS intervention were found on children's objectively measured PA and ST. Behavioural interventions for children may need to enhance specificity and intensity at the family level using other behaviour change techniques and more direct strategies to reach parents.

TAS1R3 and UCN2 Transcript Levels in Blood Cells Are Associated With Sugary and Fatty Food Consumption in Children

CONTEXT

New types of dietary exposure biomarkers are needed to implement effective strategies for obesity prevention in children. Of special interest are biomarkers of consumption of food rich in simple sugars and fat because their intake has been associated with obesity development. Peripheral blood cells (PBCs) represent a promising new tool for identifying novel, transcript-based biomarkers.

OBJECTIVE

This study aimed to study potential associations between the transcripts of taste receptor type 1 member 3 (TAS1R3) and urocortin II (UCN2) genes in PBCs and the frequency of sugary and fatty food consumption in children.

DESIGN, SETTING, AND PARTICIPANTS

Four hundred sixty-three children from the IDEFICS cohort were selected to include a similar number of boys and girls, both normal-weight and overweight, belonging to eight European countries.

MAIN OUTCOME MEASURES

Anthropometric parameters (measured at baseline and in a subset of 193 children after 2 years), food consumption frequency and transcript levels of TAS1R3 and UCN2 genes in PBCs were measured.

RESULTS

Children with low-frequency consumption of sugary foods displayed higher TAS1R3 expression levels with respect to those with intermediate or high frequency. In turn, children with high-frequency consumption of fatty foods showed lower UCN2 expression levels with respect to those with low or intermediate frequency. Moreover, transcripts of TAS1R3 were related with body mass index and fat-mass changes after a 2-year follow-up period, with low expression levels of this gene being related with increased fat accumulation over time.

CONCLUSION

The transcripts of TAS1R3 and UCN2 in PBCs may be considered potential biomarkers of consumption of sugary and fatty food, respectively, to complement data of food-intake questionnaires.

Objectively measured physical activity in European children: the IDEFICS study

OBJECTIVES

To provide sex- and age-specific percentile values for levels of physical activity (PA) and sedentary time of European children aged 2.0-10.9 years from eight European countries (Sweden, Germany, Hungary, Italy, Cyprus, Spain, Belgium and Estonia).

METHODS

Free-living PA and sedentary time were objectively assessed using ActiGraph GT1M or ActiTrainer activity monitors in all children who had at least 3 days' worth of valid accelerometer data, with at least 8 h of valid recording time each day. The General Additive Model for Location Scale and Shape was used for calculating percentile curves.

RESULTS

Reference values for PA and sedentary time in the European children according to sex and age are displayed using smoothed percentile curves for 7684 children (3842 boys and 3842 girls). The figures show similar trends in boys and girls. The percentage of children complying with recommendations regarding moderate-to-vigorous physical activity (MVPA) is also presented and varied considerably between sexes and country. For example, the percentage of study participants who were physically active (as assessed by MVPA) for 60 or more minutes per day ranged from 2.0% (Cyprus) to 14.7% (Sweden) in girls and from 9.5% (Italy) to 34.1% (Belgium) in boys.

CONCLUSION

This study provides the most up-to-date sex- and age-specific reference data on PA in young children in Europe. The percentage compliance to MVPA recommendations for these European children varied considerably between sexes and country and was generally low. These results may have important implications for public health policy and PA counselling.

Reference values of whole-blood fatty acids by age and sex from European children aged 3-8 years

OBJECTIVES

To establish reference values for fatty acids (FA) especially for n-3 and n-6 long-chain polyunsaturated FAs (LC PUFA) in whole-blood samples from apparently healthy 3-8-year-old European children. The whole-blood FA composition was analysed and the age- and sex-specific distribution of FA was determined.

DESIGN AND SUBJECTS

Blood samples for FA analysis were taken from 2661 children of the IDEFICS (identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study cohort. Children with obesity (n=454) and other diseases that are known to alter the FA composition (n=450) were excluded leaving 1653 participants in the reference population.

MEASUREMENTS

The FA composition of whole blood was analysed from blood drops by a rapid, validated gas chromatographic method.

RESULTS

Pearson correlation coefficients showed an age-dependent increase of C18:2n-6 and a decrease of C18:1n-9 in a subsample of normal weight boys and girls. Other significant correlations with age were weak and only seen either in boys or in girls, whereas most of the FA did not show any age dependence. For age-dependent n-3 and n-6 PUFA as well as for other FA that are correlated with age (16:0, C18:0 and C18:1n-9) percentiles analysed with the general additive model for location scale and shape are presented. A higher median in boys than in girls was observed for C20:3n-6, C20:4n-6 and C22:4n-6.

CONCLUSIONS

Given the reported associations between FA status and health-related outcome, the provision of FA reference ranges may be useful for the interpretation of the FA status of children in epidemiological and clinical studies.

Adherence to a Mediterranean-like dietary pattern in children from eight European countries. The IDEFICS study

BACKGROUND

Despite documented benefits of a Mediterranean-like dietary pattern, there is a lack of knowledge about how children from different European countries compare with each other in relation to the adherence to this pattern. In response to this need, we calculated the Mediterranean diet score (MDS) in 2-9-year-old children from the Identification and prevention of dietary- and lifestyle-induced health effects in children and infants (IDEFICS) eight-country study.

SUBJECTS AND METHODS

Using 24 h dietary recall data obtained during the IDEFICS study (n=7940), an MDS score was calculated based on the age- and sex-specific population median intakes of six food groups (vegetables and legumes, fruit and nuts, cereal grains and potatoes, meat products and dairy products) and the ratio of unsaturated to saturated fats. For fish and seafood, which was consumed by 10% of the population, one point was given to consumers. The percentages of children with high MDS levels (>3) were calculated and stratified by sex, age and by having at least one migrant parent or both native parents. Demographic (sex and age) and socioeconomic characteristics (parental education and income) of children showing high (>3) vs low (⩽3) MDS levels were examined.

RESULTS

The highest prevalence of children with MDS>3 was found among the Italian pre-school boys (55.9%) and the lowest among the Spanish school-aged girls (26.0%). Higher adherence to a Mediterranean-like dietary pattern was not associated with living in a Mediterranean country or in a highly educated or high-income family, although with some exceptions. Differences in adherence between boys and girls or age groups varied between countries without any general pattern.

CONCLUSIONS

With the exception of Italian pre-schoolers, similar adherence levels to a Mediterranean-like dietary pattern have been observed among European children.

Reference values for leptin and adiponectin in children below the age of 10 based on the IDEFICS cohort

OBJECTIVE

To establish age- and sex-specific reference values for serum leptin and adiponectin in normal-weight 3.0-8.9-year old European children.

SUBJECTS AND METHODS

Blood samples for hormone analysis were taken from 1338 children of the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health Effects in Children and infantS) study cohort. Only normal-weight children aged 3.0-8.9 years were included (n=539) in our analysis. Using the General Additive Model for Location Scale and Shape, age- and sex-specific percentiles were derived. The influence of under/overweight and obesity on the proposed reference curves based on normal-weight children was investigated in several sensitivity analyses using the sample without obese children (n=1015) and the whole study sample (n=1338).

RESULTS

There was a negative age trend of adiponectin blood levels and a positive trend of leptin levels in boys and girls. Percentiles derived for girls were generally higher than those obtained for boys. The corresponding age-specific differences of the 97th percentile ranged from -2.2 to 4.6 μg ml(-1) and from 2.2 to 4.8 ng ml(-1) for adiponectin and leptin, respectively.

CONCLUSIONS

According to our knowledge, these are the first reference values of leptin and adiponectin in prepubertal, normal-weight children. The presented adiponectin and leptin reference curves may allow for a more differentiated interpretation of children's hormone levels in epidemiological and clinical studies.

Metabolic syndrome in young children: definitions and results of the IDEFICS study

OBJECTIVE

To estimate the prevalence of the metabolic syndrome (MetS) using reference standards obtained in European children and to develop a quantitative MetS score and describe its distribution in children.

DESIGN AND METHODS

Population-based survey in eight European countries, including 18745 children 2.0 to 10.9 years, recruited during a second survey. Anthropometry (weight, height and waist circumference), blood pressure and serum-fasting triglycerides, HDL cholesterol, glucose and insulin were measured. We applied three widely accepted definitions of the pediatric MetS and we suggest a new definition, to guide pediatricians in decisions about close monitoring or even intervention (values of at least three of the MetS components exceeding the 90th or 95th percentile, respectively). We used a z-score standardisation to calculate a continuous score combining the MetS components.

RESULTS

Among the various definitions of MetS, the highest prevalence (5.5%) was obtained with our new definition requiring close observation (monitoring level). Our more conservative definition, requiring pediatric intervention gives a prevalence of 1.8%. In general, prevalences were higher in girls than in boys. The prevalence of metabolic syndrome is highest among obese children. All definitions classify a small percentage of thin or normal weight children as being affected. The metabolic syndrome score shows a positive trend with age, particularly regarding the upper percentiles of the score.

CONCLUSIONS

According to different definitions of pediatric MetS, a non-negligible proportion of mostly prepubertal children are classified as affected. We propose a new definition of MetS that should improve clinical guidance. The continuous score developed may also serve as a useful tool in pediatric obesity research. It has to be noted, however, that the proposed cutoffs are based on a statistical definition that does not yet allow to quantify the risk of subsequent disease.

Dietary energy density in young children across Europe

OBJECTIVES

To describe energy density (ED; kcal g(-1)) of dietary intake of European children.

METHODS

From 16, 228 children who participated in the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS) baseline examination, 8551 children with 24-h dietary recalls (24-HDR), with plausible reported energy intakes and complete covariate information were included in the present analysis. ED was calculated using two methods: (1) ED including solid foods (EDF) and (2) ED including solid foods and energy-containing beverages (EDF&B). Beverage energy was calculated in kcal per day. Dietary characteristics and body mass index (BMI) z-score of children aged 2 to <6 years and 6 to <10 years were compared between children with an overall EDF below the <25th percentile, between the 25th and 75th percentile as well as above the >75th percentile. Standardised regression coefficients were estimated to assess the association between dietary characteristics, BMI z-score and ED of the diet.

RESULTS

Children with low EDF and EDF&B diets consumed less energy but higher quantity of food and beverages than children with high EDF and EDF&B diets. Consumption of caloric beverages decreased with increasing EDF&B of the diet owing to the relatively low ED of the beverages, in relation to solid foods. Generally, children with low EDF and EDF&B diets showed healthier food choices than peers with higher EDF and EDF&B diets. In this sample, EDF and EDF&B were not associated with BMI z-score.

CONCLUSION

Health promotion strategies should proclaim lower ED diets by means of foods with high water and low fat content and mainly fruit and vegetable components. Excluding caloric beverages from EDF calculation is a useful method to avoid misinterpretation of true exposure to a high energy dense diet. We recommend excluding caloric beverages from EDF calculation when investigating the effect of ED on a certain (health) outcome.

Influence of breastfeeding on blood-cell transcript-based biomarkers of health in children

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

The expression of specific genes in peripheral blood cells (PBCs) may be used as biomarkers of the metabolic status. High levels of expression of CPT1A, SLC27A2, INSR, LEPR, FASN and PPARα in PBCs are indicative of a lower risk for the insulin resistant or dyslipidaemic state associated with obesity in children. Breastfeeding seems to confer protective effects against obesity and its related metabolic problems.

WHAT THIS STUDY ADDS

Children who had been breastfed showed higher expression levels of SLC27A2, FASN, PPARα and INSR in PBCs compared with formula-fed subjects. The relationship of the PBC transcript levels of SLC27A2, INSR, FASN and PPARα with insulin resistance and dyslipidaemia may be dependent on the type of infant feeding (breast vs. formula). The transcript levels of the mentioned biomarkers could be useful to distinguish the formula-fed children who are at higher risk of metabolic alterations.

BACKGROUND

Blood-cell transcripts have showed to be good biomarkers of metabolic alterations and their use in early detection and prevention of future disorders is promising.

OBJECTIVE

This study aimed to examine the relation between previously proposed transcriptional biomarkers of metabolic health (SLC27A2, CPT1A, FASN, PPARα, INSR, LEPR) in peripheral blood cells and the type of infant feeding in a subset of children from the IDEFICS (Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants) cohort.

SUBJECTS

A total of 237 children aged 2-9 years from eight European countries were studied.

RESULTS

Breastfed children showed higher expression levels of SLC27A2, FASN, PPARα and INSR, and lower risk of being overweight and of having high plasma triglyceride levels vs. formula-fed children. Besides, overweight formula-fed children presented higher HOMA-index than overweight breastfed children (1.90 vs. 1.62); however, this negative effect was absent in formula-fed children with high expression of SLC27A2. Moreover, formula-fed children with low expression of SLC27A2, FASN, PPARα and INSR presented higher triglyceride levels than subjects with high expression of these genes (77.7 mg dL(-1) vs. 44.8 mg dL(-1) ). This difference was absent in breastfed children.

CONCLUSIONS

Protective effects of breastfeeding are reflected in higher expression levels of SLC27A2, FASN, PPARα and INSR in blood cells. These biomarkers may also serve to discriminate the formula-fed children that are at higher risk of metabolic alterations.

Mechanisms of stress, energy homeostasis and insulin resistance in European adolescents--the HELENA study

BACKGROUND AND AIMS

Stress is hypothesized to facilitate the development of obesity, whose the foundations are already set during childhood and adolescence. We investigated the relationship between the stress-system, selected mechanisms of energy homeostasis and insulin resistance (IR) in a sample of European adolescents.

METHODS AND RESULTS

Within HELENA-CSS, 723 adolescents (12.5-17.5 years) from 10 European cities provided all the necessary data for this study. Fasting blood samples were collected for cortisol, leptin, insulin and glucose analysis. HOMA-IR was calculated from insulin and glucose concentrations. Adolescents' body fat (BF) %, age and duration of exclusive breastfeeding were assessed. For boys and girls separately, the relationship of cortisol with leptin, insulin, glucose and HOMA-IR was examined by computing Pearson correlation coefficients and Hierarchical Linear Models (HLMs), with 'city' as cluster unit, adjusting for age, BF% and duration of exclusive breastfeeding. In boys, Pearson correlation coefficients illustrated positive correlations of cortisol with insulin (r = 0.144; p = 0.013), glucose (r = 0.315; p < 0.001) and HOMA-IR (r = 0.180; p = 0.002), whilst in girls, this positive relationship was observed for leptin (r = 0.147; p = 0.002), insulin (r = 0.095; p = 0.050) and HOMA-IR (r = 0.099; p = 0.041), but not for glucose (r = 0.054; p = 0.265). Observed associations were independent of adolescents' age, BF% and duration of exclusive breastfeeding after computing HLMs.

CONCLUSION

This study suggests that the stress-system is positively related to mechanisms of energy homeostasis and IR in European adolescents, and reveals a potential small gender difference in this relationship. The hypothesis that stress might facilitate the development of obesity during adolescence is supported.

Is dairy consumption associated with low cardiovascular disease risk in European adolescents? Results from the HELENA Study

OBJECTIVE

To identify those food groups best discriminating individuals at high/low cardiovascular disease (CVD) risk and to investigate the relationship between dairy consumption and CVD risk factors (individual and scores) in adolescents (12.5-17.5 years) from eight European cities participating in the cross-sectional (2006-2007) HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) project.

METHODS

Diet, waist circumference, skin-folds thickness, systolic blood pressure, insulin resistance, triglycerides, total cholesterol/high-density lipoprotein ratio and cardiorespiratory fitness (CRF) were assessed in 511 (49.9% boys) adolescents. Individual z-scores of CVD risk factors were summed to compute sex-specific clustered CVD risk scores.

RESULTS

Dairy emerged as the food group best discriminating adolescents at low/high CVD risk. In both genders, waist circumference and sum of skin-folds were inversely associated with consumption of milk and yogurt, and milk- and yogurt-based beverages, whereas a positive association was observed with CRF. Moreover, CVD risk score (β = -0.230, P = 0.001) was also inversely associated with overall dairy consumption only in girls.

DISCUSSION

Dairy consumption is associated with lower adiposity and higher CRF in these adolescents. An inverse association between CVD risk score and dairy consumption is also depicted in girls. The study adds further evidence to the scarce literature on the influence of milk and dairy products on adolescents' cardiovascular health.

Adherence to the obesity-related lifestyle intervention targets in the IDEFICS study

BACKGROUND/OBJECTIVES

To address behaviours associated with childhood obesity, certain target values are recommended that should be met to improve children's health. In the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health Effects in Children and infantS) study such lifestyle recommendations were conveyed as six key messages. Here, we investigate the adherence of European children to these messages.

METHODS

The IDEFICS intervention was based on the intervention mapping approach with the following six targets: increase water consumption (to replace sugar-containing beverages), increase fruit/vegetable consumption, reduce daily screen time, increase daily physical activity, improve the quality of family life and ensure adequate sleep duration. Internationally recommended target values were applied to determine the prevalence of children meeting these targets.

RESULTS

In a cohort of 18,745 children participating in the IDEFICS baseline survey or newly recruited during follow-up, data on the above lifestyle behaviours were collected for a varying number of 8302 to 17,212 children. Information on all six behaviours was available for 5140 children. Although 52.5% of the cohort was classified in the highest category of water consumption, only 8.8% met the target of an intake of fruits/vegetables five times a day. The prevalence of children adhering to the recommendation regarding total screen time-below 1 h for pre-school children and 2 h for school children-was 51.1%. The recommended amount of at least 60 min of moderate-to-vigorous physical activity per day was fulfilled by 15.2%. Family life of the child measured by various indicators was considered as satisfactory in 22.8%. Nocturnal sleep duration of 11 (10) hours or more in pre-school (school) children was achieved by 37.9%. In general, children in northern countries and younger children showed better adherence to the recommendations. Only 1.1% of the children adhered to at least five of these recommendations.

CONCLUSIONS

Current adherence of children to lifestyle recommendations to prevent childhood obesity is low where observed differences with respect to country, age and gender call for targeted intervention.

Usual energy and macronutrient intakes in 2-9-year-old European children

OBJECTIVE

Valid estimates of population intakes are essential for monitoring trends as well as for nutritional interventions, but such data are rare in young children. In particular, the problem of misreporting in dietary data is usually not accounted for. Therefore, this study aims to provide accurate estimates of intake distributions in European children.

DESIGN

Cross-sectional setting-based multi-centre study.

SUBJECTS

A total of 9560 children aged 2-9 years from eight European countries with at least one 24-h dietary recall (24-HDR).

METHODS

The 24-HDRs were classified in three reporting groups based on age- and sex-specific Goldberg cutoffs (underreports, plausible reports, overreports). Only plausible reports were considered in the final analysis (N=8611 children). The National Cancer Institute (NCI)-Method was applied to estimate population distributions of usual intakes correcting for the variance inflation in short-term dietary data.

RESULTS

The prevalence of underreporting (9.5%) was higher compared with overreporting (3.4%). Exclusion of misreports resulted in a shift of the energy and absolute macronutrient intake distributions to the right, and further led to the exclusion of extreme values, that is, mean values and lower percentiles increased, whereas upper percentiles decreased. The distributions of relative macronutrient intakes (% energy intake from fat/carbohydrates/proteins) remained almost unchanged when excluding misreports. Application of the NCI-Method resulted in markedly narrower intake distributions compared with estimates based on single 24-HDRs. Mean percentages of usual energy intake from fat, carbohydrates and proteins were 32.2, 52.1 and 15.7%, respectively, suggesting the majority of European children are complying with common macronutrient intake recommendations. In contrast, total water intake (mean: 1216.7 ml per day) lay below the recommended value for >90% of the children.

CONCLUSION

This study provides recent estimates of intake distributions of European children correcting for misreporting as well as for the daily variation in dietary data. These data may help to assess the adequacy of young children's diets in Europe.

European children's sugar intake on weekdays versus weekends: the IDEFICS study

OBJECTIVES

To compare the intake of total sugars, foods and drinks rich in added sugar, and energy in children on weekdays (Monday-Thursday), Fridays and weekends.

METHODS

Dietary intake (g, kJ, energy %) was assessed using a computerized 24-h recall method in a sample of 2- to 9-year-old children from Belgium, Cyprus, Estonia, Germany, Hungary, Italy, Spain and Sweden who were participating in the IDEFICS baseline study (2007-2008). Analyses were performed in 9497 children by selecting one 24-h recall per child (for comparison of weekdays vs weekends, and Fridays vs weekdays and weekends). Selected stratified analyses were performed by country and age group.

RESULTS

Intake of total sugars exceeded 20 energy % in all countries but one. In the non-stratified analyses, the intakes of total sugars and foods and drinks rich in added sugar were found to be higher on weekends compared with weekdays (both P<0.001), and intakes on Fridays were a mix between intakes on weekdays and weekends. Energy intake did not differ between weekdays and weekends. RESULTS were somewhat heterogeneous, both across countries and age groups.

CONCLUSIONS

High intake of sugar remains an important nutritional problem in children of many European countries. Interventions aiming to prevent this diet pattern may optimize their impact by targeting dietary habits on Fridays and weekends. Furthermore, when conducting dietary assessment in children, data from weekends and Fridays in combination with a selection of Mondays to Thursdays are needed to capture habitual sugar intake. Age and dietary cultures should also be considered in dietary intervention and assessment as effect modifications were seen for both age and country.

The role of dietary fat on the association between dietary amino acids and serum lipid profile in European adolescents participating in the HELENA Study

BACKGROUND/OBJECTIVES

The objective of this study was to examine the relationship between amino acid (AA) intake and serum lipid profile in European adolescents from eight European cities participating in the cross-sectional (2006-2007) HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study, and to assess whether this association was independent of total fat intake.

SUBJECTS/METHODS

Diet, skinfold thickness, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), TC/HDL-c ratio, low-density lipoprotein cholesterol (LDL-c), apolipoprotein B (Apo B), apolipoprotein A1 (Apo A1) and Apo B/Apo A1 ratio were measured in 454 12.5- to 17.5-year-old adolescents (44% boys). Intake was assessed via two non-consecutive 24-h dietary recalls. Data on maternal education and sedentary behaviors were obtained via questionnaires. Physical activity was objectively measured by accelerometry.

RESULTS

Alanine, arginine, asparaginic acid, glycine, histidine, lysine and serine intakes were inversely associated with serum TG concentrations in both boys and girls. Intake of other AA like alanine and/or arginine was also inversely associated with serum TC, LDL-c and Apo B/Apo A1 ratio only in girls. An inverse association was observed between intakes of alanine, isoleucine, leucine, methionine, serine, tryptophan, tyrosine and valine and TC/HDL-c ratio among female adolescents. Similar results were found in males for serine and tryptophan intakes. It is noteworthy, however, that associations were no longer significant in both genders when total fat intake was considered as a confounding factor.

CONCLUSIONS

In this sample of adolescents, the association between AA intakes and serum lipid profile did not persist when dietary fat was considered. Therefore, dietary interventions and health promotion activities should focus on fat intake to improve lipid profile and potentially prevent cardiovascular disease.

Mediterranean diet, overweight and body composition in children from eight European countries: cross-sectional and prospective results from the IDEFICS study

BACKGROUND & AIMS

A Mediterranean-like dietary pattern has been shown to be inversely associated with many diseases, but its role in early obesity prevention is not clear. We aimed to determine if this pattern is common among European children and whether it is associated with overweight and obesity.

METHODS AND RESULTS

The IDEFICS study recruited 16,220 children aged 2-9 years from study centers in eight European countries. Weight, height, waist circumference, and skinfolds were measured at baseline and in 9114 children of the original cohort after two years. Diet was evaluated by a parental questionnaire reporting children's usual consumption of 43 food items. Adherence to a Mediterranean-like diet was calculated by a food frequency-based Mediterranean Diet Score (fMDS). The highest fMDS levels were observed in Sweden, the lowest in Cyprus. High scores were inversely associated with overweight including obesity (OR = 0.85, 95% CI: 0.77; 0.94) and percent fat mass (β = -0.22, 95% CI: -0.43; -0.01) independently of age, sex, socioeconomic status, study center and physical activity. High fMDS at baseline protected against increases in BMI (OR = 0.87, 95% CI: 0.78; 0.98), waist circumference (OR = 0.87, 95% CI: 0.77; 0.98) and waist-to-height ratio (OR = 0.88, 95% CI: 0.78; 0.99) with a similar trend observed for percent fat mass (p = 0.06).

CONCLUSIONS

Although a Mediterranean dietary pattern is inversely associated with childhood obesity, it is not common in children living in the Mediterranean region and should therefore be advocated as part of EU obesity prevention strategies.

Young children's screen activities, sweet drink consumption and anthropometry: results from a prospective European study

BACKGROUND/OBJECTIVES

This longitudinal study describes the relationship between young children's screen time, dietary habits and anthropometric measures. The hypothesis was that television viewing and other screen activities at baseline result in increased consumption of sugar-sweetened beverages (SSB) and increased BMI, BMI z-score and waist to height ratio (WHtR) two years later. A second hypothesis was that SSB consumption mediates the association between the screen activities and changes in the anthropometric measures.

SUBJECTS/METHODS

The study is a part of the prospective cohort study IDEFICS ("Identification and prevention of dietary and lifestyle-induced health effects in children and infants"), investigating diet, lifestyle and social determinants of obesity in 2 to 9-year-olds in eight European countries (baseline n=16,225, two-year follow-up; n=11,038). Anthropometry was objectively measured, and behaviours were parent-reported.

RESULTS

The main hypothesis was supported, but the second hypothesis was not confirmed. The odds ratio of being in the highest quintile of % change in WHtR was 1.26 (95% CI: 1.17-1.36) and in BMI 1.22 (95% CI: 1.13-1.31), for each hour per day watching television. The odds ratio of having increased SSB consumption was 1.19 (95% CI: 1.09-1.29) for each hour per day watching TV. The associations for total screen time were slightly weaker.

CONCLUSIONS

The results indicate substantial effects of TV viewing and other screen activities for young children, both on their consumption of sugary drinks and on an increase in BMI and central obesity. Our findings suggest that television viewing seems to have a stronger effect on food habits and anthropometry than other screen activities in this age group.

Food consumption and cardiovascular risk factors in European children: the IDEFICS study

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Few studies addressing the relationship between food consumption and cardiovascular disease or metabolic risk have been conducted in children. Previous findings have indicated greater metabolic risk in children with high intakes of solid hydrogenated fat and white bread, and low consumption of fruits, vegetables and dairy products.

WHAT THIS STUDY ADDS

In a large multinational sample of 2 to 9 years old children, high consumption of sweetened beverages and low intake of nuts and seeds, sweets, breakfast cereals, jam and honey and chocolate and nut-based spreads were directly associated with increased clustered cardiovascular disease risk. These findings add new evidence to the limited literature available in young populations on the role that diet may play on cardiovascular health.

OBJECTIVE

To investigate food consumption in relation to clustered cardiovascular disease (CVD) risk.

METHODS

Children (n = 5548, 51.6% boys) from eight European countries participated in the IDEFICS study baseline survey (2007-2008). Z-scores of individual CVD risk factors were summed to compute sex- and age-specific (2-<6 years/6-9 years) clustered CVD risk scores A (all components, except cardiorespiratory fitness) and B (all components). The association of clustered CVD risk and tertiles of food group consumption was examined.

RESULTS

Odds ratio (OR) of having clustered CVD risk A increased in older children with higher consumption of chocolate and nut-based spreads (boys: OR = 0.46; 95% CI = 0.32-0.69; girls: OR = 0.60; 95% CI = 0.42-0.86), jam and honey (girls: OR = 0.45; 95% CI = 0.26-0.78) and sweets (boys: OR = 0.69; 95% CI = 0.48-0.98). OR of being at risk significantly increased with the highest consumption of soft drinks (younger boys) and manufactured juices (older girls). Concerning CVD risk score B, older boys and girls in the highest tertile of consumption of breakfast cereals were 0.41 (95% CI = 0.21-0.79) and 0.45 (95% CI = 0.22-0.93) times, respectively, less likely to be at risk than those in tertile 1.

CONCLUSIONS

High consumption of sugar-sweetened beverages and low intake of breakfast cereals, jam and honey, sweets and chocolate and nut-based spreads seem to adversely affect clustered CVD risk.

Parental perceptions of and concerns about child's body weight in eight European countries--the IDEFICS study

OBJECTIVES

To evaluate parental perceptions of and concern about child's body weight and general health in children in a European cohort.

DESIGN

Cross-sectional multi-centre study in eight European countries.

PARTICIPANTS

16,220 children, ages 2-9 years.

METHODS

Parents completed a questionnaire regarding children's health and weight and concern about overweight and underweight. Objective children's weight categories from the International Obesity Task Force were used. Logistic regression models were utilized to identify predictors of accurate weight perception.

RESULTS

Parental weight perception corresponded overall to children's mean body mass index (BMI) z-scores, with important exceptions. About one-third of the total indicated concern about underweight, paradoxically most often parents of children in the overweight or obesity categories. In 63%, parents of children in the overweight category marked 'proper weight'. The strongest predictor for accurate parental weight perception for children with overweight and obesity was BMI z-score (odds ratio [OR] = 7.2, 95% confidence interval [CI] 6.1-8.7). Compared to Southern Europe, ORs for accurate parental weight perception were 4.4 (95% CI 3.3-6.0) in Northern Europe and 3.4 (95% CI 2.7-4.2) in Central Europe.

CONCLUSION

Parents of children categorized as being overweight or obese systematically underestimated weight. Parents differed regionally regarding accurate weight perception and concern about overweight and underweight.

Combined influence of healthy diet and active lifestyle on cardiovascular disease risk factors in adolescents

To investigate the combined influence of diet quality and physical activity on cardiovascular disease (CVD) risk factors in adolescents, adolescents (n = 1513; 12.5-17.5 years) participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence study were studied. Dietary intake was registered using a 24-h recall and a diet quality index was calculated. Physical activity was assessed by accelerometry. Lifestyle groups were computed as: healthy diet and active, unhealthy diet but active, healthy diet but inactive, and unhealthy diet and inactive. CVD risk factor measurements included cardiorespiratory fitness, adiposity indicators, blood lipid profile, blood pressure, and insulin resistance. A CVD risk score was computed. The healthy diet and active group had a healthier cardiorespiratory profile, fat mass index (FMI), triglycerides, and high-density lipoprotein cholesterol (HDL-C) levels and total cholesterol (TC)/HDL-C ratio (all P ≤ 0.05). Overall, active adolescents showed higher cardiorespiratory fitness, lower FMI, TC/HDL-C ratio, and homeostasis model assessment index and healthier blood pressure than their inactive peers with either healthy or unhealthy diet (all P ≤ 0.05). Healthy diet and active group had healthier CVD risk score compared with the inactive groups (all P ≤ 0.02). Thus, a combination of healthy diet and active lifestyle is associated with decreased CVD risk in adolescents. Moreover, an active lifestyle may reduce the adverse consequences of an unhealthy diet.

Short sleep duration is associated with increased obesity markers in European adolescents: effect of physical activity and dietary habits. The HELENA study

BACKGROUND

Adequate sleep is a critical factor for adolescent's health and health-related behaviors.

OBJECTIVE

(a) to describe sleep duration in European adolescents from nine countries, (b) to assess the association of short sleep duration with excess adiposity and (c) to elucidate if physical activity (PA), sedentary behaviors and/or inadequate food habits underlie this association.

DESIGN

A sample of 3311 adolescents (1748 girls) aged 12.5-17.49 years from 10 European cities in Austria, Belgium, France, Germany, Greece, Hungary, Italy, Spain and Sweden was assessed in the Healthy Lifestyle in Europe by Nutrition in Adolescence Study between 2006 and 2008. We measured anthropometric data, sleep duration, PA (accelerometers and questionnaire), television watching and food habits (Food Frequency Questionnaire).

RESULTS

Average duration of daily sleep was 8 h. Shorter sleepers showed higher values of BMI, body fat, waist and hip circumferences and fat mass index (P<0.05), particularly in females. Adolescents who slept <8 h per day were more sedentary, as assessed by accelerometry, and spent more time watching TV (P<0.05). The proportion of adolescents who eat adequate amounts of fruits, vegetables and fish was lower in shorter sleepers than in adolescents who slept ≥8 h per day, and so was the probability of having adequate food habits (P<0.05). Correlation analysis indicated that short sleep is associated with higher obesity parameters.

CONCLUSIONS

In European adolescents, short sleep duration is associated with higher adiposity markers, particularly in female adolescents. This association seems to be related to both sides of the energy balance equation due to a combination of increased food intake and more sedentary habits.

The IDEFICS community-oriented intervention programme: a new model for childhood obesity prevention in Europe?

BACKGROUND AND OBJECTIVES

The European Union-as well as other parts of the world-faces a major challenge of increasing incidence of overweight/obesity. In particular, the increase in childhood obesity gives rise to a strong imperative for immediate action. Yet, little is known about the effectiveness of community interventions, and further research in this field is needed. There is, however, a growing consensus that such research should start from the paradigm that the current living environments tend to counteract healthy lifestyles. Questioning these environments thoroughly can help to develop new pathways for sustainable health-promoting communities. Against this background, the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study developed and implemented innovative community-oriented intervention programmes for obesity prevention and healthy lifestyle primarily in children aged 2-10 years in eight European countries: Sweden, Estonia, Germany, Belgium, Hungary, Italy, Spain and Cyprus.

MATERIALS AND METHODS

The IDEFICS community-oriented intervention study mobilised an integrated set of interventional efforts at different levels of society, with the aim of facilitating the adoption of a healthy obesity-preventing lifestyle. The overall programme has been composed of 10 modules: three at community level, six at school level and one for parents. The main focus was on diet, physical activity and stress-coping capacity. The sphere of action encompassed both children and their (grand) parents, schools, local public authorities and influential stakeholders in the community. All materials for the interventions were centrally developed and culturally adapted.

RESULTS

So far, the following has been achieved: focus group research, literature review and expert consultations were done in an early phase as a basis for the development of the intervention modules. The intervention mapping protocol was followed as guide for structuring the intervention research. The overall intervention programme's duration was 2 years, but a longer-term follow-up programme is under development.

CONCLUSIONS

This large-scale European effort is expected to contribute significantly to the understanding of this major public health challenge.

Evaluation of the Children's Eating Habits Questionnaire used in the IDEFICS study by relating urinary calcium and potassium to milk consumption frequencies among European children

BACKGROUND

Measuring dietary intake in children is notoriously difficult. Therefore, it is crucial to evaluate the performance of dietary intake assessment methods in children. Given the important contribution of milk consumption to calcium (Ca) and potassium (K) intakes, urinary calcium (UCa) and potassium (UK) excretions in spot urine samples could be used for estimating correlations with milk consumption frequencies.

OBJECTIVE

The aim of this study was to evaluate the assessment of milk consumption frequencies derived from the Food Frequency Questionnaire section of the Children's Eating Habits Questionnaire (CEHQ-FFQ) used in the IDEFICS (Identification and prevention of dietary- and lifestyle induced health effects in children and infants) study by comparing with UCa and UK excretions in spot urine samples.

DESIGN

This study was conducted as a setting-based community-oriented intervention study and results from the first cross-sectional survey have been included in the analysis.

SUBJECTS

A total of 10,309 children aged 2-10 years from eight European countries are included in this analysis.

METHODS

UCa and UK excretions were measured in morning spot urine samples. Calcium and potassium urine concentrations were standardised for urinary creatinine (Cr) excretion. Ratios of UCa/Cr and UK/Cr were used for multivariate regression analyses after logarithmic transformation to obtain normal distributions of data. Milk consumption frequencies were obtained from the CEHQ-FFQ. Multivariate regression analyses were used to investigate the effect of milk consumption frequencies on UCa and UK concentrations, adjusting for age, gender, study centre, soft drink consumption and frequency of main meals consumed at home.

RESULTS

A significant positive correlation was found between milk consumption frequencies and ratios of UK/Cr and a weaker but still significant positive correlation with ratios of UCa/Cr, when using crude or partial Spearman's correlations. Multivariate regression analyses showed that milk consumption frequencies were predictive of UCa/Cr and UK/Cr ratios, when adjusted for age, gender, study centre, soft drink consumption and frequency of main meals consumed at home. Mean ratios of UK/Cr for increasing milk consumption frequency tertiles showed a progressive increase in UK/Cr. Children consuming at least two milk servings per day had significantly higher mean UCa/Cr and UK/Cr ratios than children who did not. Large differences in correlations between milk consumption frequencies and ratios of UCa/Cr and UK/Cr were found between the different study centres.

CONCLUSION

Higher milk consumption frequencies resulted in a progressive increase in UK/Cr and UCa/Cr ratios, reflecting the higher Ca and K intakes that coincide with increasing milk consumption, which constitutes a major K and Ca source in children's diet.

Fertiliser responses of maize and winter wheat as a function of year and forecrop

The N, P and K effects of mineral fertilisers were examined in a long-term fertilisation experiment set up on chernozem soil with forest residues. The data from 20 experiments on winter wheat and 24 on maize were evaluated as a function of the year, the forecrop and the soil nutrient supplies.Of the two plant species, N effects were found to be greater for winter wheat. When sown after maize, the N responses of both wheat and maize were almost 1 t ha −1 greater than when winter wheat was the forecrop. The positive effect of phosphorus was only significant in winter wheat, while that of potassium was not significant for either species.In a wheat-wheat sequence, N fertiliser alone was only effective in wet years. In winter wheat, no phosphorus effects could be detected in any year without N fertilisation. In years with extreme weather conditions, P effects were only significant when wheat was grown after cereals.In dry years nitrogen only had a significant effect on the yield of maize after wheat if it was combined with phosphorus and potassium. In years with average or above-average rainfall maize was able to extract sufficient phosphorus for its development even from soils with poor P supplies; yield increases were limited by other factors.

Design and implementation of the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study

OBJECTIVE

To provide an overview of the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS) design, with particular attention to its quality control procedures. Other important methodological aspects are described in detail throughout this supplement.

DESIGN

Description of the HELENA-CSS sampling and recruitment approaches, standardization and harmonization processes, data collection and analysis strategies and quality control activities.

RESULTS

The HELENA-CSS is a multi-centre collaborative study conducted in European adolescents located in urban settings. The data management systems, quality assurance monitoring activities, standardized manuals of operating procedures and training and study management are addressed in this paper. Various quality controls to ensure collection of valid and reliable data will be discussed in this supplement, as well as quantitative estimates of measurement error.

CONCLUSION

The great advantage of the HELENA-CSS is the strict standardization of the fieldwork and the blood analyses, which precludes to a great extent the kind of immeasurable confounding bias that often interferes when comparing results from isolated studies.

Assessing, understanding and modifying nutritional status, eating habits and physical activity in European adolescents: The HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

Objectives

To identify the main knowledge gaps and to propose research lines that will be developed within the European Union-funded ‘Healthy Lifestyle in Europe by Nutrition in Adolescence’ (HELENA) project, concerning the nutritional status, physical fitness and physical activity of adolescents in Europe.

Design

Review of the currently existing literature.

Results

The main gaps identified were: lack of harmonised and comparable data on food intake; lack of understanding regarding the role of eating attitudes, food choices and food preferences; lack of harmonised and comparable data on levels and patterns of physical activity and physical fitness; lack of comparable data about obesity prevalence and body composition; lack of comparable data about micronutrient and immunological status; and lack of effective intervention methodologies for healthier lifestyles.

Conclusions

The HELENA Study Group should develop, test and describe harmonised and state-of-the-art methods to assess the nutritional status and lifestyle of adolescents across Europe; develop and evaluate an intervention on eating habits and physical activity; and develop and test new healthy food products attractive for European adolescents.

Plasma levels of acylated ghrelin during an oral glucose tolerance test in obese children

OBJECTIVE

Ghrelin is an acylated peptide with octanoyl modification, which is essential for its GH-releasing ability. Coexpression of GH secretagogue receptor (GHS-R) and ghrelin in the pancreas suggests that this peptide is involved in glucose metabolism. The other form of the molecule, the non-acylated ghrelin, has been reported to be devoid of any pituitaric endocrine activities. Previous reports demonstrated that plasma total ghrelin levels decrease after oral glucose administration in obese children, but no data are available about the plasma levels of acylated ghrelin. Therefore, in the present study the plasma levels of acylated ghrelin were measured in obese and control children during oral glucose tolerance test (OGTT).

MATERIALS AND METHODS

Acylated ghrelin response to OGTT was evaluated in 11 obese and 9 age-matched control children. All subjects received 0.75 g/kg (maximum 75 g) glucose solution orally after an overnight fast. Acylated ghrelin, insulin, glucose, and GH were determined at 0, 30, 60 and 120 min, and leptin at 0 min of the OGTT.

RESULTS

Plasma basal levels of acylated ghrelin were significantly lower in the obese children than in the controls (66.3+/-6.7 vs 97.2+/-14.4 pg/ml, p<0.05). The plasma acylated ghrelin concentration decreased significantly at 30 and 60 min in the control group (53.3+/-9.9 and 57.4+/-7.0 pg/ml, p<0.05), but not in the obese group (64.7+/-9.6 and 49.3+/-4.6 pg/ml) as compared to the basal value. In the obese group the acylated ghrelin level was significantly higher at 120 min, than at 0 min (91.6+/-9.8 vs 66.3+/-6.7 pg/ml, p<0.05).

CONCLUSIONS

There was no rapid fall in plasma levels of acylated ghrelin in obese children after OGTT at 30 min, but there was an increase at 120 min, suggesting that the dynamic of the response to OGTT is slower and there is an upregulation of active ghrelin in the second half of OGTT in obese children.

New drug policy in childhood obesity

OBJECTIVE

To update physicians, especially paediatricians, in the rapidly developing field of pharmacotherapy of childhood and adolescent obesity.

METHODS

The paper reviews current and investigational antiobesity drugs.

RESULTS

At present, there are only few drugs approved by the Food and Drug Administration (FDA) for the treatment of adult obesity. The most important ones are sibutramine and orlistat. The FDA in the USA approved the latter drug in 2003, and it has recently been approved by the European Union for the treatment of adolescents. There are several investigational antiobesity agents but only few new and promising substances like Rimonabant (a cannabinoid receptor antagonist) and axokine (ciliary neutrotrophic factor) are already at an advanced stage of development.

CONCLUSION

In adults, it seems to be justified using drugs for long-term treatment of 'medically important' obesity. Strict guidelines concerning the treatment of obese adolescents with orlistat are needed. It is only hoped that double-blind placebo-controlled studies investigating the new and promising drugs will also include adolescents and provide sufficient scientific data to get them licensed for the treatment of obese adolescents.

The frequency of Trp64Arg polymorphism of the β3-adrenergic receptor gene in healthy and obese Hungarian children and its association with cardiovascular risk factors

OBJECTIVE

To estimate the frequency of Arg64 allele of the beta(3)-adrenergic receptor (3-BAR) gene in healthy (H) and obese (O) Hungarian children, and to look for possible associations between this polymorphism and some clinical and metabolic characteristics of obese children.

PATIENTS/METHODS

In all, 147 healthy (male: 68) and 295 obese (male: 168) children were examined. The average age of the children in the two groups was 12.4+/-1.7 vs 12.6+/-3.2, respectively. Exon 1 of 3-BAR was amplified by polymerase chain reaction and the fragments were digested with BstN1. In obese children, oral glucose tolerance test was carried out and blood pressure (BP) was checked.

RESULTS

The frequency of Trp64Arg polymorphism in normal and obese Hungarian children was similar (H vs O: n=14/9.5% vs n=35/11.8%). Obese children carrying the Arg64 allele (n=35, male: 23) were compared to randomly chosen, obese children without the Arg64 allele (n=35, male: 20). A significant difference was found between the body weight (81.2+/-23.2 vs 75.6+/-17.7 kg; mean+/-s.d.; P<0.01), body fat (38.8+/-3.9 vs 36.5+/-2.3%; mean+/-s.d.; P<0.05), mean fasting insulin levels (31.4+/-16.7 vs 16.9+/-7.6 microIU/ml; P<0.001) and mean systolic BP values (125.2+/-10.1 vs 114.5+/-8.3 mmHg; P<0.001) of the two obese groups.

CONCLUSIONS

The frequency of Trp64Arg polymorphism was similar in Hungary as compared to other European countries. Although the prevalence of this polymorphism was similar in H and O children, the presence of Arg64 allele seems to be associated with increased adiposity, elevated systolic BP and higher fasting insulin levels.

The prevalence of the metabolic syndrome and type 2 diabetes mellitus in children and adolescents

OBJECTIVE

To review the prevalence of the metabolic syndrome and type 2 diabetes in children and adolescents.

METHOD

Literature review.

RESULTS

It is well demonstrated that cardiovascular risk factors are frequent in childhood obesity and they tend to cluster. However, the frequency of the metabolic syndrome in childhood and adolescence has been investigated only by few studies. In spite of the diverse criteria used for defining the metabolic syndrome, it is evident that the syndrome is already highly prevalent among obese children and adolescents. Population-based data suggest that the epidemic of pediatric obesity is being followed by an increase of type 2 diabetes mellitus, especially in the United States and in minorities. For the European countries, there are no population-based incidence and prevalence data concerning type 2 diabetes mellitus in children and adolescents. From the available data, the magnitude of the problem in the European Caucasian population seems to be much less than in North America.

CONCLUSION

There is an urgent need to establish internationally acceptable criteria for the metabolic syndrome in children and adolescents and to commence screening for this syndrome. Although type 2 diabetes mellitus is still rare among European children, screening is recommended for type 2 diabetes mellitus or impaired glucose tolerance in children and especially in adolescents with substantial risk for the development of this disease.

Reduced antioxidant status in obese children with multimetabolic syndrome

BACKGROUND

In our previous study, the negative correlation found between plasma insulin levels and plasma alpha-tocopherol concentrations suggested that decreased antioxidant vitamin levels and reduced antioxidant capacity might be a characteristic feature of obese children with multimetabolic syndrome (MMS).

OBJECTIVE

To investigate lipid-soluble antioxidant vitamin levels and total antioxidant status (TAS) in obese children with and without MMS and in controls.

SUBJECTS

In total, 16 control children (age: 16.2+/-1.1 y, BMI: 20.7+/-1.9 kg/m(2), body fat (BF): 25.6+/-5.7%; mean+/-s.d.), 15 obese children (age: 13.4+/-2.1 y, BMI: 34.2+/-3.1 kg/m(2), BF: 36.9+/-5.8%,) and 17 obese children without MMS (age: 14.4+/-2.3 y, BMI: 30.4+/-6.2 kg/m(2), BF: 36.3+/-5.8%) were included in the study.

METHODS

Body composition was determined by anthropometric methods. Vitamin analysis was carried out by high-performance liquid chromatography and TAS of the plasma was measured with commercially available kits. Plasma glucose, lipids and insulin were measured by standard laboratory methods.

RESULTS

Plasma alpha-tocopherol and beta-carotene levels corrected for plasma lipids (cholesterol + triglyceride) were significantly (P<0.05) lower in obese children with MMS (2.4 (3.1) micromol/mmol and 12.3 (24.0) pmol/mmol, respectively, median (range from the first to the third quartile)), than in the obese without MMS (3.7 (0.9) micromol/mmol and 48.2 (27.7) pmol/mmol) and in the control group (3.8 (0.7) micromol/mmol and 86.6 (44.5) pmol/mmol). Plasma TAS values of the MMS group (1.2 (0.4) mmol/l) were also significantly (P<0.05) reduced as compared to obese children without MMS (1.62 (0.14) mmol/l) and to controls (1.58 (0.21) mmol/l).

CONCLUSION

Obese children with MMS are prone to oxidative stress. Further investigations are necessary to determine if these children may benefit from vitamin E and beta-carotene supplementation.

Low physical performance in obese adolescent boys with metabolic syndrome

OBJECTIVE

To assess cardiorespiratory exercise function in obese children with and without metabolic syndrome (MS).

DESIGN

Comparing three groups of subjects with different cardiovascular risk profiles.

SUBJECTS

Twenty-two MS (body weight (mean+/-s.d.) 97.3+/-15.3 kg; age (mean+/-s.d.) 14.2+/-1.9 y), 17 obese (82.6+/-15.7 kg; 14.2+/-2.6 y) and 29 normal weight control (64.3+/-8.5 kg; 15.3+/-1.0 y) boys.

MEASUREMENTS

Exercise duration (ED), resting heart rate (HR(0)), peak heart rate (HR(peak)), physical working capacity at 170 beat/min (PWC-170), peak oxygen consumption (VO(2peak)) and the lactic acidosis threshold (LAT) were determined on treadmill, using a continuous ramp protocol.

RESULTS

ED (MS (mean+/-s.d.); 655+/-86 s; obese 703+/-64 s; control 750+/-0 s) in absolute value and PWC-170 normalised for body weight (139+/-40 w; 177+/-40 w; 211+/-40 w) were significantly shorter and lower in the MS group, as compared to obese and control groups (P<0.05). VO(2peak) (2.2+/-0.4 l/min; 2.4+/-0.5 l/min; 2.9+/-0.4 l/min) and LAT (1.3+/-0.4 l/min; 1.5+/-0.4 l/ min; 1.8+/-0.4 l/min) normalised for body weight, were significantly shorter and lower in the MS group, as compared to control group (P<0.05). HR(0) was significantly higher (P<0.05) in MS group than in obese and control groups (88+/-12 bpm; obese 78+/-10 bpm; 73+/-10 bpm).

CONCLUSION

Cardiorespiratory exercise performance capacity in MS boys are reduced. It still remains to be elucidated whether the metabolic alterations or the decreased physical activity is responsible for the observed reduction in cardiorespiratory performance.