Overweight and obesity in Portuguese children and adolescents

MULT: A new BMI reference to assess nutritional status of multi-ethnic children and adolescents

OBJECTIVES

To develop a new Body Mass Index (BMI) reference (MULT) based on longitudinal data of multi-ethnic populations and to compare it to international BMI references.

METHODS

The MULT BMI reference was constructed through the LMS method and the Generalized Additive Models for Location Scale and Shape (GAMLSS), with 81 310 observations of 17 505 subjects aged 0-22 years old, from the United Kingdom, Ethiopia, Peru, India, Vietnam, Brazil, and Portugal. Outlier values were removed based on weight z-scores (population level) and based on BMI z-scores using the linear mixed effects model (individual level). The MULT M, S and L curves were compared to the ones of the World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), International Obesity Task Force (IOTF), and Dutch Growth Study (DUTCH). The MULT BMI percentile cutoffs for overweight and obesity were calculated using the adult BMI values of 25 and 30 kg/m2 at 17, 18, 19, and 20 years old.

RESULTS

MULT presented the lowest mean BMI values for the ages 102-240 months for boys and 114-220 months for girls. MULT S values were similar to the WHO and IOTF for children under 60 months of age and the highest during puberty, while the L curve showed to be more symmetric than the other BMI references.

CONCLUSION

The MULT BMI reference was constructed based on recent data of populations from 10 countries, being a good option to assess the nutritional status of multi-ethnic populations.

Body Composition and Physical Fitness in Madeira Youth

BACKGROUND

Research on composition and physical fitness is lacking in school-aged children from Madeira. This study aimed to examine the frequencies of overweight and obese participants and, in addition, to compare the fitness levels of Madeira youth with reference data.

METHODS

The sample comprised 521 participants (n = 258 boys; n = 263 girls) aged 10.0-18.9 years old.

METHODS

Height and weight were measured. Body mass index (BMI) was calculated, and percent fat was derived from skinfolds. Tests detailed on FITESCOLA battery were performed. BMI was plotted against U.S. reference data and physical assessment contrasted with the cut-off points of FITESCOLA protocol and corresponding data developed in Portuguese youth.

RESULTS

The percentages of overweight and obesity were 15% (overweight) and 14% (obesity) for boys and 16% (overweight) and 6% (obesity) for girls. The median values of fat mass percentage were closely related to the cut-off standards; however, substantial variation was noted. Boys and girls tended to be below the recommendations of cardiorespiratory fitness.

CONCLUSIONS

Sport participation should be promoted in Madeira to attain acceptable values of body composition and physical fitness levels.

Exploring Overweight Risk Trajectories During Childhood and Their Associations With Elevated Blood Pressure at Late Adolescence: a Retrospective Cohort Study

BACKGROUND

Overweight during childhood is significantly associated with higher risk of high blood pressure (HBP) in later life. However, recognition of critical intervention period is limited. We aimed to analyze the changes in overweight risk during school-age and its relationship with HBP.

METHODS

Seventeen thousand eight hundred sixteen school-aged children (53.9% boys) with a mean follow-up time of 8.2 years were involved. Children's overweight was defined as body mass index Z score ≥1 and was fitted with a group-based trajectory model. The 4 trajectories were labeled as constant low, high decreasing, low rising, and constant high according to the change of overweight risk during follow-up. Population-averaged logit model and log-binomial regression models were used to analyze HBP risk. Cox proportional hazard model was used to analyze the HBP incidence among distinct groups.

RESULTS

Children with higher overweight risk generally had higher HBP risk during follow-up. However, the HBP risk in low rising group was low at baseline and increased to 3.14 (95% CI, 2.54-3.88; P<0.001) for boys and 3.23 (95% CI, 2.08-5.01; P=0.004) for girls at end point, which were comparable to the relative risk in the constant high group (4.60 [95% CI, 4.02-5.27] for boys and 5.28 [95% CI, 3.94-7.07] for girls).

CONCLUSIONS

Findings of this study provide insights on patterns of overweight risks during childhood. Children with transition from normal to overweight during teen years would be high-risk in HBP incidence.

Overweight and Obesity in Children of Immigrant Versus Native Parents: Exploring a Local Setting in Portugal

In Portugal, the majority of immigrants come from Portuguese-speaking countries. Among children, overweight and obesity are serious public health concerns, but a few studies include children with immigrant background. This study aimed to estimate the prevalence of overweight and obesity and risk of abdominal obesity in school-age children and to explore potential determinants, considering the origin of the children’s parents (both mother and father are non-Portuguese, only one Portuguese, and both are Portuguese). A cross-sectional study included a random sample of 789 children (5–11 years old, 49.2% of males and 50.8% female) attending public primary schools in Barreiro, district of Setubal, Portugal. Fieldwork occurred from 20th April to 3rd July 2009. Data concerning socioeconomic, eating habits, and sports outside school were obtained through a questionnaire applied to the children’s person in charge. Anthropometric measures were collected by certified technicians. One-third of the children presented overweight and obesity (33.7%, 95% CI [30.0; 37.7]) and risk of abdominal obesity (16.4%, 95% CI [13.6; 19.7]) without differences according to parents’ origin. Children with immigrant background presented higher consumption of low-priced, high-sugar, and high-fat foods, with a worse situation for girls. Females from both non-Portuguese parents also practiced less sports outside school than those where one or two parents are Portuguese. Thus, promoting and monitoring a healthy diet and physical activity in this group should be prioritized in this local setting.

Prevalence of overweight and obesity in 3-to-10-year-old children: assessment of different cut-off criteria WHO-IOTF

This study compares the prevalence of overweight and obesity between WHO/IOTF criteria. A total of 17,277 Portuguese children aged 3-10 years old were analysed. The prevalences of overweight-obesity were higher at WHO classification (19.8%-20.7%) than at IOTF classification (8.2%-16.1%), (p<0.001). Agreement between the criteria were substantial for overweight (Kappa= 0.67, p<0.001) and moderate for obesity (Kappa= 0.47, p<0.001). The prevalences ratio for inequality between criteria were greater for boys than for girls and lesser for children aged 6-7 than children aged 8-10 years old. The disparities between the two criteria and the higher overweight obesity prevalences highlight the needs to develop more studies.

Overweight and obesity in Portuguese children: prevalence and correlates

There are widespread differences in overweight/obesity prevalence in children, and understanding the reasons for this is very important. The present study aims: (I) to conduct a meta-analysis on overweight/obesity prevalence in Portuguese children; (II) to identify differences in biological and behavioural characteristics between normal-weight and overweight/obese children; and (III) to investigate the importance of individual- and school-level correlates of variation in children's BMI using multilevel modelling. A search was done for all published papers including Portuguese children during the last decade; further, 686 Portuguese children (9-11 years old) were sampled and their BMI, family income, maturity offset, nutritional habits, physical activity, sedentariness, sleep time, and school environment information were collected. Results showed a stabilization of overweight/obesity during the last decade, 30.6% (95%CI: 0.287-0.34) for boys, 28.4% (95%CI: 0.23-0.35) for girls, and 30.3% (95%CI: 0.27-0.34) for boys and girls together. Differences between weight groups were only found in individual-level biological traits. The multilevel analysis did not identify significant contributions of school-level variables to children's BMI variation. In conclusion, no increase was found in the prevalence of overweight/obesity among Portuguese children since 2000. Normal-weight and overweight/obese children only differ in individual-level characteristics, and school context variables were not related to variation in BMI.

Evaluating the effect of energy-dense foods consumption on preschool children's body mass index: a prospective analysis from 2 to 4 years of age

PURPOSE

The aim of this study was to study the association between the consumption of energy-dense foods at 2 years and body mass index (BMI) at 4 years, using a cross-lagged panel design.

METHODS

The present study included 589 children evaluated at 2 and 4 years of age, as part of the birth cohort generation XXI. Information was obtained by face-to-face interviews. Consumption of energy-dense foods (salty snacks, soft drinks, cakes, and sweets) was measured using a food frequency questionnaire. Children's weight and height were measured by standard procedures, and BMI standard deviation scores (BMI z-scores) were calculated according to the World Health Organization. Linear regression and cross-lagged panel design models were fitted to estimate the associations between the consumption of energy-dense foods and BMI z-scores (controlled for maternal age, education and prepregnancy BMI, and children's exact age at 2 years).

RESULTS

The consumption of energy-dense foods at 2 years was significantly associated with their consumption at 4 years (β = 0.522, 95% CI 0.432-0.612). Children's BMI z-scores at 2 years were associated with posterior BMI z-scores (β = 0.747, 95% CI 0.688-0.806). In the cross-lagged analysis, consumption of energy-dense foods at 2 years had no effect on subsequent BMI z-scores (β = -0.030, 95% CI -0.095 to 0.035) and BMI z-scores at 2 years were not significantly associated with the consumption of energy-dense foods at 4 years (β = -0.012, 95% CI -0.086 to 0.062).

CONCLUSIONS

Consumption of energy-dense foods and BMI tracked over time, but the consumption of energy-dense foods at 2 years was not associated with BMI z-scores at 4 years.

Socio-demographic and behavioral risk factors associated with the high prevalence of overweight and obesity in Portuguese children

OBJECTIVES

Childhood obesity is a public health concern in Portugal. Socio-demographic and behavioral factors are highly associated with obesity but are not clearly understood. This article aims to update the prevalence of overweight and obesity in Portuguese children and to explore the influence and risks of socio-demographic factors and behavioral factors.

METHODS

A cross-sectional study of Portuguese children aged 3-10 years from all 18 mainland districts took place between March 2009 and January 2010. The sample was composed by 17,136 children, 3-10 years of age (8,455 boys; 8,681 girls). Height, weight, and other anthropometric measurements were obtained by trained technicians. Body mass index (BMI) was calculated along with other anthropometric variables. Data analyses took place between April and September 2012. The overweight/obesity classification was established by age-and sex-specific BMI cut-off points as defined by the International obesity task force (IOTF). Parents completed questionnaires about socio-demographic and behavioral characteristics of the family.

RESULTS

Almost 28% of the Portuguese children were overweight or obese (19.7% overweight; 8.2% obese). Prevalence was greater in girls than in boys. Logistic regression models found that the odds of childhood obesity were significantly affected by biological, socio-demographic, and behavioral factors.

CONCLUSIONS

The protective factors against childhood overweight/obesity in this sample of Portuguese children are: (i) being male; (ii) having been breastfeed; (iii) having been born from mothers who did not smoke during pregnancy; (iv) engaging in little sedentary behaviors (TV, PC, and playing electronic games); (iv) performing at least 1 h of moderate physical activity every day; and (v) having parents with higher educational levels who also have their BMI within the healthy ranges.

Prevalence of overweight/obesity and its association with sedentary behavior in children

OBJECTIVE

The aim of this study was to determine the prevalence of overweight and obesity in children in the northeast region of Portugal, and to examine its association with sedentary behavior.

METHODS

Data were collected on 1786 children (907 boys, 879 girls) aged 6 to 13 years. Body mass index was calculated from measured height and weight (weight in kg/height in m squared). Overweight and obesity were determined using the International Obesity Task Force cutoff values. Sedentary behavior was assessed based on means of transport to and from school and time spent watching TV and playing video games (TVPC).

RESULTS

The prevalences of overweight and obesity were 22.6% and 9.4% respectively. The differences between the sexes for both overweight and obesity were not significant. Most of the children (78.4%) go to school by car. Boys spend more time on TVPC than girls, both on weekdays and on weekends. The logistic regression model indicated a significant effect of 1.5 hours of TVPC by boys during weekdays (OR=0.246; p=0.015). Boys who spent less than 1.5 hours on weekdays on TVPC were 75.4% less likely to be overweight than those who spent more than 1.5 hours.

CONCLUSION

The prevalence of overweight and obesity was 32%. Only 12.2% of the children spend less than 1.5 hours on TVPC. Boys who spend less than 1.5 hours on TVPC are 75.4% less likely to be overweight/obese than those who spend more than 1.5 hours.

The impact of an intervention taught by trained teachers on childhood overweight

The purpose of this study was to assess the effects of a six-months’ nutrition program, delivered and taught by classroom teachers with in-service nutrition training, on the prevention of overweight and obesity among children in grades 1 to 4. In this randomized trial, four hundred and sixty four children from seven elementary schools were allocated to a nutrition educational program delivered by their own teachers. Intervened teachers had 12 sessions of three hours each with the researchers throughout six months, according to the topics nutrition and healthy eating, the importance of drinking water and healthy cooking activities. After each session, teachers were encouraged to develop activities in class focused on the learned topics. Sociodemographic, anthropometric, dietary, and physical activity assessments were performed at baseline and at the end of the intervention. In the intervention group the increase in Body Mass Index (BMI) z-score was significantly lower than in the control group (p = 0.009); fewer proportion of children became overweight in the intervened group compared with the control (5.6% vs. 18.4%; p = 0.037). Our study provides further support to decrease the overweight epidemic, involving classroom teachers in a training program and making them dedicated interventionists.

Engaging municipalities in community capacity building for childhood obesity control in urban settings

BACKGROUND

Reducing rates of child obesity requires an approach that transcends the medicalization of overweight. Family practice doctors and public health professionals need to work with other sectors to establish comprehensive approaches to obesity reduction.

OBJECTIVES

This study compares the approaches of three cities with different health and political systems (Lisbon, London and New York City) to promoting effective action to decrease child obesity.

METHODS

Using a comparative case study approach, participant observers in three intersectoral municipal collaborative on child obesity describe their challenges and accomplishments.

RESULTS

Municipal governments made child obesity a policy priority and coordinate efforts in different sectors. Public health provided relevant information on population characteristics and scientific evidence for decision-making, family practice monitored children's growth and assisted families to adopt healthy behaviors. These sectors, together with university-based researchers, also played an advocacy role, addressing inequalities, alerting the public and policy makers about damaging products or risky situations, and regulating private interests that threaten well-being, e.g., the food and beverage industry that promotes unhealthy products. Local, national and global networks of health providers, municipal agencies and researchers have helped to diagnose problems, coordinate action across sectors and levels, share and evaluate successes and failures, translate evidence into practice and promote social cohesion.

CONCLUSIONS

These cities have developed common approaches and face similar challenges in reducing high rates of child obesity, suggesting that it may be possible for cities in different parts of the world to learn from each other and thus accelerate progress.

Disordered eating among preadolescent boys and girls: the relationship with child and maternal variables

OBJECTIVE

(i) To analyze the eating behaviors and body satisfaction of boys and girls and to examine their mothers' perceptions of these two domains; and (ii) to evaluate eating problem predictors using child body mass index (BMI), self-esteem, and body satisfaction as well as maternal BMI, eating problems, and satisfaction with their child's body. The participants included 111 children (54.1% girls aged between 9 and 12 years old) and their mothers. Assessment measures included the Child Eating Attitude Test, the Self-Perception Profile for Children, the Eating Disorders Questionnaire, and the Child Eating Behavior Questionnaire. Child and maternal measures also included BMI and Collins Figure Drawings.

RESULTS

(i) No association between child and maternal BMI for either sex was found; (ii) no difference was found between boys and girls with regard to eating behavior; (iii) most children revealed a preference for an ideal body image over their actual body image; (iv) most mothers preferred thinner bodies for their children; (v) greater BMI was related to higher body dissatisfaction; and (vi) child BMI and dissatisfaction with body image predicted eating disturbances in boys, whereas self-esteem, maternal BMI, and eating behavior predicted them in girls.

DISCUSSION

Maternal eating problems and BMI were related to female eating problems only.

Changes in adiposity status from childhood to adolescence: a 6-year longitudinal study in Portuguese boys and girls

BACKGROUND

Cross-sectional data show high prevalence of overweight in Portuguese children, but there are few longitudinal studies describing the patterns of obesity development in the young.

AIM

To examine the trajectories of obesity from late childhood to adolescence.

SUBJECTS AND METHODS

Triceps and subscapular skinfold thickness measurements were carried out in 288 children at age 9 (baseline) and later at age 15 (follow-up). Percentage body fat (%BF) was estimated according to Slaughter equations and the health-related definition of obesity ( ≥ 25%BF in boys and ≥ 30%BF in girls) was used.

RESULTS

In boys, the prevalence of obesity decreased from 21.9% to 14.8% (p < 0.05) while in girls it increased from 14.3% to 19.5%. The incidence of obesity in the 6-year study period was 2.6% and 8.3% for boys and girls, respectively (p < 0.05). In comparison with girls, the percentage of boys that reversed obesity was more than 3-fold higher (3% vs 9.7%, p < 0.05). Obesity tracked moderately in both sexes (Kappa = 0.6, p < 0.001).

CONCLUSION

The results indicate a marked sex difference in the incidence and reversal of obesity from late childhood to adolescence that is unfavourable to girls. Consideration of this difference might be important when designing programmes for the prevention and treatment of obesity focusing on this period.

Food patterns according to sociodemographics, physical activity, sleeping and obesity in Portuguese children

Our study aimed to describe the association between food patterns and gender, parental education, physical activity, sleeping and obesity in 1976 children aged 5−10 years old. Dietary intake was measured by a semi quantitative food frequency questionnaire; body mass index was calculated and categorized according to the IOTF classification. Factor analysis and generalized linear models were applied to identify food patterns and their associations. TV viewing and male gender were significant positive predictors for fast-food, sugar sweetened beverages and pastry pattern, while a higher level of maternal education and longer sleeping duration were positively associated with a dietary patterns that included fruit and vegetables.

Prevalence of overweight and obesity among 7-9-year-old children in Aveiro, Portugal: comparison between IOTF and CDC references

OBJECTIVE

To estimate the prevalence of overweight and obesity in schoolchildren from Aveiro, Portugal, according to two criteria: the International Obesity Task Force (IOTF) and the US Centers for Disease Control and Prevention (CDC) cut-offs.

DESIGN

Weight, height and waist circumference were measured. Using the BMI, gender- and age-specific prevalences of overweight and obesity were determined according to the IOTF cut-offs extrapolated from an adult BMI of 25 and 30 kg/m2 and the CDC cut-off values of 85th and 95th BMI percentile.

SETTING

Aveiro, Portugal.

SUBJECTS

A random representative sample of 905 children (457 boys; 448 girls) aged 7-9 years.

RESULTS

The prevalence of excess weight (overweight and obesity) was lowest according to IOTF cut-offs compared to CDC (28.1 % v. 31.2 %), especially obesity (8.1 % v. 14.0 %). However, the CDC and IOTF criteria have a strong agreement (Cohen's k = 0.755; P < 0.001). There were significant differences in excess weight between boys and girls according to the CDC (26.9 % v. 35.7 %; P = 0.003). Obese children are younger and the majority present abdominal obesity.

CONCLUSIONS

The present study shows a high prevalence of excess weight in Aveiro children, similar to other Portuguese regions and among the highest in Europe, especially in the female gender. The IOTF cut-off values give a lower prevalence of excess weight, namely obesity.