Emergence and persistence of overweight and obesity in 7- to 11-year-old children

Prevalence and trends of underweight in European children and adolescents: a systematic review and meta-analysis

PURPOSE

This study aimed at providing prevalence trend estimates of underweight among children and adolescents in Europe from 2000 to 2017.

METHODS

MEDLINE, Web of Science, Scopus and CINAHL were searched from their inception up to March 2020. Moreover, searches were conducted on health institutions' websites to identify studies not published in scientific journals. Underweight was defined according to the body mass index (BMI) cut-offs proposed by the International Obesity Task Force (IOTF) and the World Health Organization (WHO) definition criteria. The Mantel-Haenszel method was used to compute the pooled prevalence estimates whenever there was no evidence of heterogeneity; otherwise, the DerSimonian and Laird random-effects method was used. Subgroup analyses by sex, age range (2-13 and 14-18 years old), study year (2000-2006 and 2007-2017), country and European region were conducted.

RESULTS

A total of 49 studies with data from 323,420 children and adolescents aged 2 to 18 years, from 26 countries were included. From 2000 to 2017, according to the IOTF criteria, the prevalence of underweight showed an increasing trend in Eastern, Northern and Southern Europe, where the underweight prevalence ranged from 9.1 to 12.0%, from 4.1 to 6.8%, and from 5.8 to 6.7%, respectively. In Western Europe, the prevalence of underweight tended to decrease, from 14.0 to 11.8%. No significant differences were found by sex or age range.

CONCLUSION

The prevalence of underweight is considerable (overall, around 8-9%), particularly in Eastern Europe, and follows a slight upward trend during the past decade.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017056924.

Prevalence and Trends of Overweight and Obesity in European Children From 1999 to 2016: A Systematic Review and Meta-analysis

IMPORTANCE

Studies of trends in excess weight among European children throughout the last few decades have rendered mixed results. Additionally, some studies were outdated, were based on self-reported weight and height, or included only a few European countries.

OBJECTIVE

To assess prevalence trends in measured overweight and obesity among children across Europe from 1999 to 2016 using a systematic methodology.

DATA SOURCES

MEDLINE, Embase, CINAHL, and Web of Science were searched from their inception until May 2018. Moreover, searches were conducted on health institutions' websites to identify studies not published in scientific journals.

STUDY SELECTION

The inclusion criteria were: (1) studies reporting the population-based prevalence of excess weight (overweight plus obesity) or obesity according to body mass index cutoffs proposed by the International Obesity Task Force; (2) cross-sectional or follow-up studies; and (3) studies including populations aged 2 to 13 years.

DATA EXTRACTION AND SYNTHESIS

Literature review and data extraction followed established guidelines. The Mantel-Haenszel method was used to compute the pooled prevalence estimates and their 95% CI whenever there was no evidence of heterogeneity (I2 < 50%); otherwise, the DerSimonian and Laird random-effects method was used. Subgroup analyses by study year, country, or European region (Atlantic, Iberian, Central, and Mediterranean) were conducted. Prevalence estimates were calculated as an aggregate mean, weighted by the sample size and the number of individuals in each study.

RESULTS

A total of 103 studies (477 620 children aged 2 to 13 years) with data from 28 countries were included. The combined prevalence of overweight and obesity in the Iberian region tended to decrease from 30.3% (95% CI, 28.3%-32.3%) to 25.6% (95% CI, 19.7%-31.4%) but tended to increase in the Mediterranean region from 22.9% (95% CI, 17.9%-27.9%) to 25.0% (95% CI, 14.5%-35.5%). No substantial changes were observed in Atlantic Europe or Central Europe, where the overweight and obesity prevalence changed from 18.3% (95% CI, 14.0%-23.9%) to 19.3% (95% CI, 17.7%-20.9%) and from 15.8% (95% CI, 13.4%-18.5%) to 15.3% (95% CI, 11.6%-20.3%), respectively.

CONCLUSIONS AND RELEVANCE

The prevalence of childhood overweight and obesity is very high, but trends have stabilized in most European countries. There are substantial between-country differences in the current levels and trends of overweight and obesity. The rising prevalence in some Mediterranean countries is worrisome.

TRIAL REGISTRATION

PROSPERO identifier: CRD42017056924.

A Characterization of Movement Skills in Obese Children With and Without Prader-Willi Syndrome

PURPOSE

The aim of this study was twofold: (a) to measure and compare motor proficiency in obese children with Prader-Willi syndrome (OB-PWS) to that in obese children without PWS (OB), and (b) to compare motor proficiency in OB-PWS and OB to normative data.

METHOD

Motor proficiency was measured using the Bruininks-Oseretsky Test of Motor Proficiency-Second Edition-Complete Form, a norm-referenced assessment of motor function. Participants were 18 OB-PWS and 44 OB (8 to 11 years of age). The scores on the 8 subtests and the total motor composite were used to compare OB-PWS and OB. Furthermore, the scores on the 4 motor-area composites were used to compare OB-PWS and OB against normative data.

RESULTS

OB-PWS scored significantly lower than OB across all 8 subtests. OB-PWS also had significantly lower motor proficiency scores on all motor-area composites when compared with the normative sample. OB-PWS most frequently (67%-83%) scored well below average on the gross motor subtests. Although not as high as on the gross motor subtests, this finding also held true for the fine motor subtests with 39% to 45% of OB-PWS scoring well below average.

CONCLUSION

Motor proficiency is very poor in OB-PWS, in particular for gross motor skills. Physical, neurological, and developmental characteristics inherent to the syndrome may explain this low performance.

Pathophysiology of hypertension in obese children: a systematic review

Hypertension is increasingly common in overweight and obese children. The mechanisms behind the development of hypertension in obesity are complex, and evidence is limited. In order to effectively treat obese children for hypertension, it is important to have a deeper understanding of the pathophysiology of hypertension in obese children. The present review summarizes the main factors associated with hypertension in obese children and discusses their potential role in its pathophysiology. Systematic searches were conducted in PubMed and EMBASE for articles published up to October 2014. In total, 60 relevant studies were included. The methodological quality of the included studies ranged from weak to strong. Several factors important in the development of hypertension in obese children have been suggested, including endocrine determinants, such as corticosteroids and adipokines, sympathetic nervous system activity, disturbed sodium homeostasis, as well as oxidative stress, inflammation and endothelial dysfunction. Understanding the pathophysiology of hypertension in overweight and obese children is important and could have implications for its screening and treatment. Based on solely cross-sectional observational studies, it is impossible to infer causality. Longitudinal studies of high methodological quality are needed to gain more insight into the complex mechanisms behind the development of hypertension in obese children.

Changes in objectively measured BMI in children aged 4-11 years: data from the National Child Measurement Programme

BACKGROUND

This study looked at the degree of weight gain between the first (Reception) and last year (Year 6) of primary school and how weight status in Reception predicts becoming overweight/obese by Year 6.

METHODS

A longitudinal sample of 1863 children was created using two time points (2006/7, 2012/13) from the National Child Measurement Programme (NCMP) in South Gloucestershire. T-test and logistic regression were used to test the difference between the BMI z-scores and BMI percentiles, and predict the probability of being overweight (BMI ≥ 85th) or obese (≥95th) at Year 6 based on BMI percentile in Reception.

RESULTS

Of those children who were obese at Reception age, 68% were obese at Year 6. Compared with children with a BMI in the 2nd to 49th percentile range, children between the 75th and 84th percentiles of BMI at Reception age were 10 times more likely (odds ratio (OR) = 10.18, P < 0.01), and those with a BMI between the 85th and 94th percentiles were 13 times more likely (OR = 13.38, P < 0.01), to become obese by Year 6. Boys were more likely than girls to revert to a healthy weight.

CONCLUSIONS

This is the first study to link data from the NCMP. It provides estimates of prevalence and offers new evidence on obesity emergence and gender differences.

Is it time for bed? Short sleep duration increases risk of obesity in Mexican American children

OBJECTIVE

Cross-sectional studies show that sleep is related to childhood obesity. We aimed to examine the longitudinal impact of sleep on the risk of obesity in Mexican American children.

DESIGN AND METHODS

We evaluated 229 Mexican American 8-10-year-olds and their mothers at baseline and at 12- and 24-month follow-ups. Sleep duration and anthropometrics were collected. Age- and gender-specific body mass index (BMI) z-scores (BMIz) were calculated based on Centers for Disease Control and Prevention guidelines. Sleep duration was estimated using accelerometry. Children were also categorized as long or short sleepers, using the National Sleep Foundation's recommendation to define adequate sleep duration (10-11 h for 5-12-year-olds). Using linear regressions, we examined whether sleep duration predicted BMIz, waist-to-height ratio (WHtR), and weight gain at 24 months.

RESULTS

Children were mostly short sleepers (82%). Children who slept less were more likely to have a higher BMIz, WHtR, and weight gain at the 24-month follow-up (β = -0.07, P = 0.01; β = -0.11, P <0.01; and β = -0.14, P = 0.02, respectively), after controlling for baseline weight status, child gender, maternal BMI, and occupation.

CONCLUSION

In Mexican American children, shorter sleep duration at baseline was associated with increased weight status over 24 months.