Inequality in physical activity, sedentary behaviour, sleep duration and risk of obesity in children: a 12-country study

Association between sleep duration and latency, nocturnal awakenings, and body mass index among infants

OBJECTIVE

To investigate the association between sleep duration, nocturnal awakenings, and sleep latency with body mass index (BMI) at six and 12 months of age.

METHODS

179 children from a birth cohort were enrolled. At six and 12 months of age, anthropometric data were obtained using standardized techniques and infants' mothers answered the Brief Infant Sleep Questionnaire for sleep data. The association of BMI with the independent variables (sleep duration, latency, and nocturnal awakenings) was assessed by linear regression models. Analyses were adjusted for potential confounders and a p-value<0.05 was adopted to define statistical significance.

RESULTS

For each additional hour of sleep duration, BMI was reduced by 0.15 kg/m² (95% confidence interval [CI] -0.28; -0.01; p=0.03) and each additional minute of sleep latency increased BMI by 0.01 kg/m² (95%CI -0.00; 0.03; p=0.02). These associations were independent of gestational age, child sex, birth weight, duration of exclusive breastfeeding, smoking during pregnancy, and mother's BMI, education, and marital status. Nocturnal awakenings showed no association with the outcome.

CONCLUSIONS

Our findings suggest that sleep duration and sleep latency time are associated with BMI in the first year of life. Insights into the influence of sleep early in life on weight status may be helpful to complement future nutritional recommendations and prevent and treat obesity.

Gender differences in the distribution of children's physical activity: evidence from nine countries

BACKGROUND

Physical activity in childhood is thought to influences health and development. Previous studies have found that boys are typically more active than girls, yet the focus has largely been on differences in average levels or proportions above a threshold rather than the full distribution of activity across all intensities. We thus examined differences in the distribution of physical activity between girls and boys in a multi-national sample of children.

METHODS

We used the harmonised International Children Accelerometry Database (ICAD), including waist-worn accelerometry data from 15,461 individuals (Boys: 48.3%) from 9 countries. Employing Generalised Additive Models of Location, Shape, and Scale (GAMLSS) we investigated gender differences in the distribution of individuals, including comparisons of variability (SD) and average physical activity levels (mean and median) and skewness. We conducted this analysis for each activity intensity (Sedentary, Light, and Moderate-to-Vigorous (MVPA)) and a summary measure (counts per minute (CPM)).

RESULTS

Sizable gender differences in the distribution of activity were found for moderate to vigorous activity and counts per minute, with boys having higher average levels (38% higher mean volumes of MVPA, 20% higher CPM), yet substantially more between-person variability (30% higher standard deviation (SD) for MVPA, 17% higher SD for CPM); boys' distributions were less positively skewed than girls. Conversely, there was little to no difference between girls and boys in the distribution of sedentary or light-intensity activity.

CONCLUSIONS

Inequality in activity between girls and boys was driven by MVPA. The higher mean volumes of MVPA in boys occurred alongside greater variability. This suggests a need to consider the underlying distribution of activity in future research; for example, interventions which target gender inequality in MVPA may inadvertently lead to increased inequality within girls.

The impact of the COVID-19 pandemic on inequalities in lifestyle behaviours and mental health and wellbeing of elementary school children in northern Canada

Objectives

The COVID-19 pandemic has negatively affected children's lifestyle behaviours and mental health and wellbeing, and concerns have been raised that COVID-19 has also increased health inequalities. No study to date has quantified the impact of COVID-19 on health inequalities among children. We compared pre-pandemic vs. post-lockdown inequalities in lifestyle behaviours and mental health and wellbeing among children living in rural and remote northern communities.

Methods

We surveyed 473 grade 4-6 students (9-12 years of age) from 11 schools in rural and remote communities in northern Canada in 2018 (pre-pandemic), and 443 grade 4-6 students from the same schools in 2020 (post-lockdown). The surveys included questions on sedentary behaviours, physical activity, dietary intake, and mental health and wellbeing. We measured inequality in these behaviors using the Gini coefficient, a unitless measure ranging from 0 to 1 with a higher value indicating greater inequality. We used temporal changes (2020 vs. 2018) in Gini coefficients to assess the impact of COVID-19 on inequalities in lifestyle behaviours and mental health and wellbeing separately among girls and boys.

Results

Inequalities in all examined lifestyle behaviours increased between 2018 and 2020. Inequalities in watching TV, playing video games, and using a cell phone increased among girls, while inequalities in playing video games, using computers and tablets, and consumption of sugar, salt, saturated fat and total fat increased among boys. Changes in inequalities in mental health and wellbeing were small and not statistically significant.

Conclusion

The findings suggest that the COVID-19 pandemic has exacerbated inequalities in lifestyle behaviours among children living in rural and remote northern communities. If not addressed, these differences may translate into exacerbated inequalities in future health. The findings further suggest that school health programs can help mitigate the negative impact of the pandemic on lifestyle behaviours and mental health and wellbeing.

The Portuguese economic crisis is associated with socioeconomic and sex disparities on children's health-related behaviors and obesity: A cross-sectional study

OBJECTIVES

Our objective was to examine the relationship between the 2008 and 2015 economic crisis and children's physical activity (PA) outcomes, eating behaviors and obesity prevalence, while considering sex inequalities and familial socioeconomic status.

METHOD

This is a cross-sectional study, including data collected in 2016/2017 among 5134 children aged 6-11 years (mean age: 8.11 ± 1.24; 50.0% boys). Children's height, weight, and waist circumference were objectively measured. Children's sleep- and screen-time, participation in organized sports, and specific dietary habits were reported parental-reported using a standardized questionnaire. An economic crisis impact score, with data from 10 indicators of economic needs in the family, was used to characterize the crisis' impact.

RESULTS

First, the prevalence of overweight and obesity was higher in children whose families had a higher impact of the crisis. Second, children's intake of fruit and high-fat food, screen-time, sleep-time, and participation in organized sports differed according to the level of impact of the economic crisis. Third, the association between health-related behaviors and the impact of the economic crisis was stronger for girls compared to boys.

CONCLUSION

Our findings give us an indication of how economic crises may drive changes in health outcomes.

Investigaciones realizadas en Colombia relacionadas con actividad física y obesidad 2010-2020

Introducción: La obesidad es un problema de salud pública mundial. La actividad física es una herramienta importante de promoción y prevención de este problema. Se desconoce las investigaciones realizadas en Colombia al respecto, lo cual es necesario para implementar políticas públicas eficientes. Objetivo: analizar las investigaciones colombianas encontradas en bases de datos científicas sobre la actividad física y obesidad. Metodología: revisión sistemática de artículos de investigación realizados en Colombia del año 2010 al 2020, en las bases de datos PubMed y SciELO.  Resultados: de 87 artículos encontrados, 23 cumplieron los criterios de inclusión. El 91,3 % publicados en revistas indexadas internacionalmente. 69,5% estudios observacionales, 17,4% ensayos clínicos y 8,7% revisiones sistemáticas. Conclusiones: poca producción en Colombia. La mayoría en revistas indexadas, tuvieron diseño observacional y encontraron asociación entre poca actividad física con sobrepeso/obesidad. Alta prevalencia de sobrepeso/obesidad. Pocos autores fueron profesionales en el área del deporte y el entrenamiento. Introduction: Obesity is a global public health problem. Physical activity and exercise are important tools for promoting and preventing. The research carried out in Colombia in this regard is unknown, which is necessary to implement efficient public policies. Objective: to analyze Colombian research found in scientific databases on physical activity or exercise in overweight and obesity. Methodology: literary review of research articles carried out in Colombia from 2010 to 2020, in the PubMed and SciELO databases. Results: Of 87 articles found, 23 met the inclusion criteria. 91.3% published in internationally indexed journals. 69.5% observational studies, 17.4% clinical trials and 8.7% systematic reviews. Conclusions: little production in Colombia. Most of the indexed journals had an observational design and found an association between little physical activity and overweight/obesity. High prevalence of overweight/obesity. Few authors were professionals in the area of training.

Refining index to measure physical activity inequality: which group of the population is the most vulnerable?

BACKGROUND

The existing body of research mostly discusses inequality in physical activity (PA) based on the difference in the level of moderate-to-vigorous physical activity (MVPA). Evidence is lacking on the quantified inequality measures (e.g., how big the inequality is, and the distribution) in order to identify the most vulnerable groups of a population. This study measured PA inequality among Thai adults by using three parameters to construct an inequality index: (1) Proportion of the population with sufficient MVPA; (2) Cumulative minutes of MVPA; and (3) The Gini coefficient.

METHODS

This study employed three rounds of data from Thailand's Surveillance on Physical Activity (SPA) 2019-2021. In each round, over 6,000 individuals age 18-64 years were selected as nationally-representative samples, and were included in the analysis. PA inequality was constructed by using three parameters, with a combination of the three as the final measure, to identify the sub-groups of the Thai adults who are most vulnerable: groups with the least MVPA, highest insufficiency, and highest inequality index (Gini).

RESULTS

Covid-19 containment measures have widened the gap in PA inequality, as shown by a declining proportion of the population meeting the recommended guidelines, from 74.3% in 2019 to 56.7% in 2020 and 65.5% in 2021. PA inequality existed in all sub-populations. However, by combining three parameters, the most vulnerable groups during the Covid-19 epidemic were identified as follows: (1) Those with no income; (2) The unemployed; (3) Those who have no access to PA facilities; (4) Older adults aged 60 + years; and (5) Those earning < 3,500 baht per month. Further, residents of Bangkok, young adults aged 18-24, individuals who attained primary level education or less, those who had no exposure to a PA awareness campaign and those who have a debilitating chronic disease also had elevated risk of PA insufficiency.

CONCLUSION

A concerning level of PA inequality existed in all sub-populations. The use of combined indicators in measuring PA inequality should aid in determining the most vulnerable groups of the population with a refined procedure. This method can be applied in many settings since the baseline data used to measure inequality (i.e., percent sufficient and cumulative minutes of MVPA) are widely available.

Accurate Step Count with Generalized and Personalized Deep Learning on Accelerometer Data

Physical activity (PA) is globally recognized as a pillar of general health. Step count, as one measure of PA, is a well known predictor of long-term morbidity and mortality. Despite its popularity in consumer devices, a lack of methodological standards and clinical validation remains a major impediment to step count being accepted as a valid clinical endpoint. Previous works have mainly focused on device-specific step-count algorithms and often employ sensor modalities that may not be widely available. This may limit step-count suitability in clinical scenarios. In this paper, we trained neural network models on publicly available data and tested on an independent cohort using two approaches: generalization and personalization. Specifically, we trained neural networks on accelerometer signals from one device and either directly applied them or adapted them individually to accelerometer data obtained from a separate subject cohort wearing multiple distinct devices. The best models exhibited highly accurate step-count estimates for both the generalization (96-99%) and personalization (98-99%) approaches. The results demonstrate that it is possible to develop device-agnostic, accelerometer-only algorithms that provide highly accurate step counts, positioning step count as a reliable mobility endpoint and a strong candidate for clinical validation.

Sleep, sedentary behavior, and physical activity in Brazilian adolescents: Achievement recommendations and BMI associations through compositional data analysis

Physical activity, sedentary behavior (SB), and sleep are habitual human behaviors (HHB) which are modifiable throughout the different life phases. Therefore, it is necessary to analyze how the time distribution throughout the day among HHB may be associated with body mass index (BMI). These results could provide inferences which can guide interventions that trigger changes in adolescent behaviors in favor of their health. The objective of this study was to verify the proportion of adolescents who meet the recommendation of sleep, moderate to vigorous physical activity (MVPA), and screen time (ST); to analyze the associations between HHB and BMI, and to determine possible changes in BMI associated with time reallocation between different HHB. Daily HHB recommendations (yes/no) were analyzed by frequency distribution. Compositional data analyses were used to examine the association between HHB and the BMI z-score (zBMI) with covariates (sex, age, and socioeconomic status). Compositional isotemporal substitution models estimated the change in zBMI associated with HHB reallocations from 15 to 120 minutes. A total of 185 adolescents were included (15 to 18 years, 50.8% boys). Thus, total sleep time, SB, light physical activity (LPA) and MVPA were measured by 24-hour accelerometry for seven consecutive days. ST, demographic characteristics, and socioeconomic status were assessed using a questionnaire. Sleep, MVPA, and ST recommendations were achieved by 32.97%, 8.10%, and 1.08% of the sample, respectively. No adolescent was able to achieve all of the daily recommendations. Age was significantly and positively associated with zBMI (p<0.001). Simply replacing 75, 90, and 120 minutes of MVPA by LPA led to an estimated significant increase in zBMI (95CI% z-value, 0.01 to 1.49). The HHB relocation estimates in 24h did not show positive effects on zBMI, nor did it increase the time engaged in MVPA, which may raise the hypothesis that other parameters related to obesity and their related interactions need to be better understood.

Meeting 24-h movement guidelines: prevalence, correlates and associations with socioemotional behavior in Spanish minors

The aims of this study were to determine for the first time the prevalence of a national sample of Spanish minors meeting the 24‐h movement guidelines; to determine their correlates; and to examine their associations with socioemotional behavioral problems. Cross‐sectional data from the Spanish National Health Survey (2017) were analyzed for this study. A total of 3772 Spanish minors were included. Physical activity was parent‐reported by a modified short version of the International Physical Activity Questionnaire, which included a single question related to the participation in physical activity in free time. Recreational screen time was parent‐reported by asking respondents for weekdays and weekends independently: “How much time does your child typically spend in front of a screen, including a computer, tablet, television, video, video game, or cell phone screen?”. Sleep duration was parent‐reported by the following question: “Can you tell me approximately how many hours your child usually sleeps daily?”. The Strengths and Difficulties Questionnaire was applied for the evaluation of socioemotional behavioral problems. The prevalence of meeting of all the three guidelines was 13.5%. Compared to meeting all guidelines, higher odds of socioemotional behavioral problems were found in participants meeting two guidelines (OR = 1.42; CI95%, 1.10–1.83), one guideline (OR = 1.50; 95%CI,1.14–1.96), or none of the guidelines (OR = 1.92; 95%CI,1.30–2.83). Our study demonstrated that the proportion of Spanish minors who meet with all the 24‐h movement guidelines is low. Furthermore, it could be relevant to the promotion of the 24‐h movement guidelines to prevent the risk of socioemotional behavioral problems.

School physical activity policies and associations with physical activity practices and behaviours: A systematic review of the literature

The development and implementation of school policies is considered a key strategy for the promotion of physical activity (PA) in children and adolescents. This study aimed to systematically review and synthesise existing literature focusing on the associations between formal written school-based PA policies and (a) school PA practices and (b) PA behaviours of school-aged children and adolescents. Fifty-one papers reporting on 52 studies met the eligibility criteria. All but two studies were from high income countries, most used cross-sectional designs and demonstrated fair methodological quality, and just over a third examined language aspects of policies. Findings predominantly indicated a lack of or inconclusive associations between the various characteristics examined and PA outcomes. Inconclusive associations were identified between both PA practice and behaviour outcomes and state level policies, policies focusing on PE and school-day PA, and in studies examining language aspects of policies. Inconclusive associations with both types of outcomes were more likely to be identified compared to a lack of associations in studies using self-report measures and in studies not providing information about the quality of exposure and outcome measures used. Overall, findings highlight the need for further research that acknowledges the complex relationship between school policies and PA outcomes and employs robust methodological approaches to enhance our understanding of this area.

Independent and combined influences of physical activity, screen time, and sleep quality on adiposity indicators in Indian adolescents

BACKGROUND

Inadequate physical activity (PA), excess screen time (ST), and sub-optimal sleep quality tend to co-occur during adolescence. Yet, little is known about the associations of these behaviors as a cluster with adiposity indicators in Indian adolescents. This study aimed to evaluate the independent and combined influences of PA, ST, and sleep quality on body mass index (BMI) and waist to height ratio (WHtR) in 10-15 years old adolescents in Mumbai, India. A secondary aim was to explore if these influences vary between sexes.

METHODS

Cross-sectional study. Adolescents (n = 772, mean age 13.2 (1.4) years) reported frequency and duration of moderate to vigorous PA (MVPA) and time spent using screens on a previously validated instrument. Sleep quality was estimated using the Pittsburg Sleep Quality Index (PSQI). Weight, height, and waist circumference were measured. Mixed effect logistic regression analyses were performed to explore associations between adiposity indicators (BMI z scores > +1SD and WHtR > 0.5) and unhealthy behaviors (PA < 60 min/d, ST > 120 min/d and PSQI scores > 5), stratified by sex.

RESULTS

The combined prevalence of overweight and obesity was 38.3%. Overall, 62.0 and 85.0% reported MVPA< 60 min/d and ST > 120 min/d respectively. Girls reported higher ST (218.21 (69.01) min/d) as compared to boys (165.3 (101.22) min/d, p < 0.001). Clustering of low PA and excess ST was observed in 69.2% and of all three unhealthy behaviors in 18.8%. Among girls, MVPA < 60 min/d (OR = 1.78, 95% CI 1.54-1.92, p < 0.001) and PSQI scores > 5 (OR = 2.01, 95% CI 1.78-2.25, p < 0.001) predicted increased BMI. The odds of overweight/obesity were 2.10 times higher in boys reporting low PA and 4.13 times higher in those with low PA+ ST > 120 min/d. Clustering of all three unhealthy behaviors increased prevalence of obesity in both sexes.

CONCLUSIONS

The results indicated a co-existence of multiple unhealthy lifestyle factors of obesity and that clustering of these behaviors can further aggravate obesity risk as compared to their independent effects. Integrated interventions that leverage the cumulative benefits of being active, less sedentary and sufficient sleep are warranted to facilitate greater improvements in obesity risk behaviors.

Association between sociodemographic, dietary, and substance use factors and accelerometer-measured 24-hour movement behaviours in Brazilian adolescents

Sociodemographic factors and lifestyle behaviours were evidenced as correlates of self-reported 24-hour movement behaviours in high-income settings. However, it is unclear how these relations occur in a middle-income country setting, with unique cultural and social characteristics. This study aimed to examine the association between sociodemographic, dietary, and substance use factors with accelerometer-measured 24-hour movement behaviours in Brazilian adolescents. Information on sex, age, socioeconomic status (SES), family structure, dietary behaviours, and history of substance use were collected by a questionnaire. Sleep duration, sedentary behaviour, and light- and moderate-to-vigorous physical activity (LPA and MVPA) were measured using wrist-worn accelerometers. On average, females slept more (β = 21.09, 95%CI 13.18; 28.98), engaged in more LPA (β = 17.60, 95%CI 8.50; 27.13), and engaged in less sedentary behaviour (β = -16.82, 95%CI -30.01; -4.30) and MVPA (β = -4.76, 95%CI -7.48; -1.96) than males. Age and sedentary behaviour were positively associated (β = 8.60, 95%CI 2.53; 14.64). Unprocessed foods were positively related to LPA (β = 2.21, 95%CI 0.55; 3.92), whereas processed foods were positively related to sedentary behaviour (β = 3.73, 95%CI 0.03; 7.38) and inversely related to MVPA (β = -0.89, 95%CI -1.68; -0.10). Family structure, SES, and substance use factors were not significantly associated with any 24-hour movement behaviour.Conclusions: Sex, age, and dietary behaviours, unlike SES or substance use, were associated with 24-hour movement behaviours in this sample of Brazilian adolescents and are important factors to consider in interventions, policies, and practice. What is Known: • The 24-hour movement behaviours are composed of sleep, sedentary behaviour, and physical activity and are important determinants of health. • Most adolescents do not engage in adequate levels of physical activity, sedentary behaviour, and sleep, and there is a need to better understand factors related to these behaviours. What is New: • Sex, age, and dietary behaviours were associated with the 24-hour movement behaviours. • No associations were found between socioeconomic status and substance use with the 24-hour movement behaviours.

[Socioeconomic inequalities in the prevalence of excess weight and sedentary behavior among Brazilian adolescents]

The scope of this study was to estimate the prevalence of excess weight and a sedentary lifestyle among Brazilian students between 13 and 17 years of age and investigate the magnitude of the socioeconomic inequalities related to these outcomes. A cross-sectional study was carried out based on data from the National School Health Survey (PeNSE) conducted in 2015. Inequalities were evaluated using the Absolute and Relative Index of Inequality. The prevalence of excess weight in Brazil was 24.2%, ranging from 20.7% in the Northeast Region to 27.8% in the Southern Region. The prevalence of a sedentary lifestyle in Brazil was 67.8%, ranging from 61.8 % in the North Region to 70.3% in the Southeast Region. The direct and positive association between better socioeconomic conditions and the prevalence of excess weight and a sedentary lifestyle indicate health inequities in Brazil. The results of this study point to the need to restructure and reinforce public policies directed at adolescents, which should have as guidelines the promotion of a healthy lifestyle and the reduction of health inequities.

Associations between Sociodemographic, Dietary, and Substance Use Factors with Self-Reported 24-Hour Movement Behaviors in a Sample of Brazilian Adolescents

We aimed to identify sociodemographic, dietary, and substance use factors associated with self-reported sleep duration, physical activity (PA), and sedentary behavior (SB) indicators in a sample of Brazilian adolescents. Adolescents (n = 731, 51% female, mean age: 16.4 years) answered a questionnaire. The volume of total PA, sports, non-sports, total SB, leisure-time SB, involuntary SB, sleep duration, dietary behaviors, sociodemographic, and substance use indicators were self-reported. Multilevel linear models were fitted. Females engaged in less total PA, sports, total SB, and leisure-time SB, but in more involuntary SB than males. Age was positively associated with non-sports and involuntary SB. Socioeconomic status was positively associated with total PA. Adolescents who lived with the mother only practiced more sports compared to those living with two parents. Unprocessed food was positively associated with total PA and sports. Processed food was inversely associated with total PA and non-sports, and positively associated with total SB and leisure-time SB. Alcohol use was positively associated with total PA, and tobacco smoking was negatively associated with total PA. No associations were observed for sleep duration. In conclusion, sociodemographic, dietary, and substance use factors are associated with the 24 h movement behaviors among Brazilian adolescents, and some associations are type specific.

PROMIS Paediatric Mobility tool is correlated with accelerometer-measured physical activity in children with hip diseases

AIMS

The reduction in mobility due to hip diseases in children is likely to affect their physical activity (PA) levels. Physical inactivity negatively influences quality of life and health. Our aim was to objectively measure PA in children with hip disease, and correlate it with the Patient-Reported Outcomes Measurement Information System (PROMIS) Mobility Score.

METHODS

A total of 28 children (12 boys and 16 girls) with hip disease aged between 8and 17 years (mean 12 (SD 3)) were studied between December 2018 and July 2019. Children completed the PROMIS Paediatric Item Bank v. 2.0 - Mobility Short Form 8a and wore a hip accelerometer (ActiGraph) for seven consecutive days. Sedentary time (ST), light PA (LPA), moderate to vigorous PA (MVPA), and vigorous PA were calculated from the accelerometers' data. The PROMIS Mobility score was classified as normal, mild, and moderate functions, based on the PROMIS cut scores on the physical function metric. A one-way analysis of covariance (ANCOVA) was used to assess differences among mobility (normal; mild; moderate) and measured PA and relationships between these variables were assessed using bivariate Pearson correlations.

RESULTS

Children classified as normally functioning on the PROMIS had less ST (p = 0.002), higher MVPA, (p = 0.002) and VPA (p = 0.004) compared to those classified as mild or moderate function. A moderate correlation was evident between the overall PROMIS score and daily LPA (r = 0.462, n = 28; p = 0.013), moderate-to-vigorous PA (r = 0.689, n = 28; p = 0.013) and vigorous PA (VPA) (r = 0.535, n = 28; p = 0.013). No correlation was evident between the mean daily ST and overall PROMIS score (r = -0.282, n = 28; p = 0.146).

CONCLUSION

PROMIS Pediatric Mobility tool correlates well with experimentally measured levels of physical activity in children with hip disease. We provide external validity for the use of this tool as a measure of physical activity in children. Cite this article: Bone Joint J 2021;103-B(2):405-410.

Physical activity, sedentary time and sleep in cystic fibrosis youth: A bidirectional relationship?

PURPOSE

Physical activity (PA) and sleep are highly important for those with cystic fibrosis (CF), yet, despite this and suggestions of a bidirectional relationship between these factors in healthy children, their relationship is yet to be investigated.

METHODS

PA, sedentary time (SED), and sleep were objectively derived over seven days in 58 youth (11.9 ± 2.7 years; 29 CF). Generalized linear latent and mixed models with a random intercept and slope at child-level were adjusted for age, sex, wear-time, type of day, group and mean PA/SED and sleep.

RESULTS

Every additional 10 min sedentary was associated with 5.6 and 5.0 min less sleep and 10.6 and 12.0 min less wake after sleep onset (WASO) that night, in CF and healthy children, respectively. PA, regardless of intensity, was not associated with total sleep time but every additional 10 min of light PA (LPA) was associated with 3.0 min less WASO in healthy participants. Ten mins more sleep was associated with 3.1 and 1.7 min less SED in CF and healthy children, respectively. In CF, greater sleep time led to less LPA (3.6 min) the following day, whereas, in healthy children, poor sleep quality (greater WASO) was associated with more LPA (1.4 min) and moderate-to-vigorous PA (5.2 min) the following day.

CONCLUSION

A bidirectional relationship between SED and subsequent total sleep time was evident, irrespective of group, whereas the relationship between sleep and PA was group dependent. These findings have important implications regarding the reciprocal effects of promoting PA or sleep quantity or quality.

Adequate sleep duration among children and adolescents: a review of the Brazil's Report Card

abstract – This study aimed to summarize existing research examining the prevalence of adequate sleep duration or meeting sleep recommendations among Brazilian children and adolescents. A systematic review was conducted on eight databases. The criteria for inclusion were original research, samples including Brazilian children and adolescents (age 0–18), studies that reported variables regarding sleep duration using both objective or subjective measures, school- or population-based surveys with random sampling, and cross-sectional or cohort studies. Of the 54 articles included, only 27 used data from different studies. Most of the studies were conducted in the southern region (n = 17) with only two studies having a nationally representative sample. Two studies included children below age five, and the age group most investigated was adolescents (>10 years old). A majority of the studies used a self-reported questionnaire and showed variability in the cutoff point applied for adequate sleep duration with the most reported being ≥8 hours. The proportion of adolescents who met recommendations or had adequate sleep duration ranged from 15% to 89%. Among children, the prevalence ranged from 17% to 95%. The least variability was observed among toddlers, ranging from 93% to 95%. No consistent gender differences were observed among the gender-stratified groups of children and adolescents across the studies. It can be observed that, because of the wide range of results and the lack of data with national representativeness, the prevalence of sufficient sleep among young people aged below 18 remains undefined in Brazil.

A healthy behavior and socioeconomic inequality in school-age children in the West of Iran

BACKGROUND

Sufficient physical activity (SPA) in children and adolescents has an important role in health, growth, and development of persons. This study aimed to investigate the prevalence of and inequality in physical activity (PA) in 12-15-year-old students in the West of Iran, 2018.

MATERIALS AND METHODS

In this cross-sectional study, 1404 students from 14 schools of Kermanshah city were included. Data on demographic and socioeconomic status (SES) of students and their family, body mass index, moderate-to-vigorous PA of students were collected. Normalized concentration index (NC) and decomposition analysis applied to measure inequality in SPA and the contribution of affecting factors, respectively.

RESULTS

About 19% of the students had SPA. The proportion of SPA in boys was higher than girls (38.98% vs. 9.84%). There was a significant deviation from equality line (NC = 0.31; 95% confidence interval [CI]: 0.23, 0.38) and NC for boys and girls were 0.15 (95% CI: 0.04, 0.25) and 0.05 (95% CI: -0.07, 0.17). Sex of students and SES of households with 59.09% and 39.77% contribution to the measured inequality in SPA were the highest positive contributors. Household size (-2.60) had a negative contribution to inequality in SPA.

CONCLUSION

There was a significant pro-rich socioeconomic inequality in SPA and sex, and SES were the main contributors to the inequality in PA. Some interventions are needed to improve PA among children and adolescents with a focus on girls and low-SES groups to narrow the existing gaps.

Self-reported symptoms of depression, anxiety and stress in Portuguese primary school-aged children

BACKGROUND

Symptoms of depression, anxiety and stress experienced during childhood might have a negative impact on development. This study explores factors associated with such symptoms among Portuguese primary school-aged children.

METHODS

A sample of children (n = 1022, mean age = 8.77 years old) was recruited in public and private schools from the cities of Coimbra, Lisbon and Porto, Portugal. The children's version of the Depression, Anxiety and Stress Scale (DASS-C) was self-administered. Multivariate logistic regression models were fitted to measure associations (expressed as Odds Ratio, OR and 95% Confidence Intervals, CI) between each DASS-C subscale, dichotomized by its 4th vs. 3rd or less quartiles (symptoms increase with scores), and covariates: child sex, age, socioeconomic status (SES), sports activity beyond school, children self-assessed health status, child and mother's body mass index and mother's DASS scores.

RESULTS

Age was negatively associated with anxiety symptoms (adjusted OR, 95% CI: 0.70, 0.57-0.87) and girls, compared to boys, presented lower odds of depressive and stress symptoms (adjusted OR, 95% CI: 0.65, 0.47-0.92 and 0.57, 0.41-0.80, respectively). A low socioeconomic status was associated with more frequent symptoms of stress (adjusted OR, 95%CI for low compared to high SES: 1.61, 1.01-2.56). Children with poorer self-assessed health status and whose mothers scored higher in the DASS also presented significantly higher odds of scoring in the 4th quartile (vs. 3rd or less) of the three DASS-C subscales.

CONCLUSIONS

These results suggest the need to tailor preventive efforts targeting childhood mental health symptoms.

Body mass index and movement behaviors among schoolchildren from 13 countries across a continuum of human development indices: A multinational cross-sectional study

OBJECTIVE

This study describes the distributions of body mass index (BMI) and movement behaviors among schoolchildren from 13 countries across a continuum of human development.

METHODS

Data were from a cross-sectional study of 9-11-year-old children (n = 8055) recruited from 269 urban schools in 13 countries, and an additional 7 rural schools in one of these countries (Mozambique). BMI was derived from objectively measured heights and weights. Moderate- to vigorous-intensity physical activity (MVPA), sedentary time (SED), and sleep duration were assessed by waist-worn Actigraph GT3X+ accelerometers. Linear models were used to describe the distributions of BMI z-scores, MVPA, SED, and sleep among sites across varying Human Development Indices (HDIs).

RESULTS

Mean MVPA, SED, and sleep duration were 63.1 ± 27.3 minutes/day, 508.7 ± 72.4 minutes/day, and 8.8 ± 0.9 hours/night, respectively. Overall, 2.1% of the sample were thin, 19.5% overweight, and 11.7% were obese. Density curves (BMI z-scores and SED) for urban children in Mozambique showed significantly higher mean values compared with rural children. Boys had significantly higher mean MVPA compared with girls. Mean BMI z-scores were positively associated (β = .02; P = .004) with HDI, mean daily MVPA minutes were negatively associated (β = -.38; P = .025) with HDI, and mean SED time was positively associated with HDI (β = 1.18; P = .049). No significant association (β = .01; P = .29) was observed between sleep duration and HDI.

CONCLUSION

Our findings show distinct differences in BMI and movement behavior profiles between urban and rural children in Mozambique. Mean BMI z-scores, MVPA, and SED differed by country HDI. These findings support the need to include both rural and urban participants in study samples.

International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE): Contributions to Understanding the Global Obesity Epidemic

The purpose of this review is to summarize the scientific contributions of the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE) in extending our understanding about obesity in children from around the world. ISCOLE was a multi-national study of 9 to 11 year-old children from sites in 12 countries from all inhabited continents. The primary purpose was to investigate relationships between lifestyle behaviors and obesity, and the influence of higher-order characteristics such as behavioral settings, and physical, social and policy environments. ISCOLE has made several advances in scientific methodology related to the assessment of physical activity, dietary behavior, sleep and the neighborhood and school environments. Furthermore, ISCOLE has provided important evidence on (1) epidemiological transitions in obesity and related behaviors, (2) correlates of obesity and lifestyle behaviors at the individual, neighborhood and school levels, and (3) 24-h movement behaviors in relation to novel analytical techniques. A key feature of ISCOLE was the development of a platform for international training, data entry, and data quality for multi-country studies. Finally, ISCOLE represents a transparent model for future public-private research partnerships across low, middle and high-income countries.