Physical activity of children in the "Childhood Obesity Project" trial

Ziele: Das tägliche Bewegungsverhalten in der Kindheit hat einen großen Einfluss auf die momentane und zukünftige Gesundheit von Kindern. Ein höheres Niveau an körperlicher Aktivität (KA) und weniger Zeit in sitzenden Tätigkeiten (ST) während den ersten Lebensjahren ist positiv mit dem Bewegungsverhalten im Erwachsenenalter assoziiert. Zudem kann ein adäquater Umfang an KA und eine Reduktion von Inaktivität zur Prävention von kindlichem Übergewicht und Adipositas beitragen. In dieser Arbeit untersuche ich sowohl KA als auch ST bei Kindern vom 6. Bis zum 11 Lebensjahr, um ein besseres Verständnis für die Veränderung des Bewegungsverhaltens während der Kindheit zu erhalten. Ein weiteres Ziel ist es, mögliche Assoziationen mit anthropometrischen Messgrößen zu untersuchen. Methoden: Die Daten für diese Arbeit stammen aus der europäischen Childhood Obesity Project Studie (CHOP), die in fünf europäischen Ländern durchgeführt wurde. Der Umfang an KA und ST wurde mit sechs, acht und elf Jahren mit Hilfe des Sensewear Armbands 2 gemessen. Gewicht, Fettmasse und Größe der Kinder wurden den jeweiligen Messzeitpunkt erhoben und die anthropometrische Messgrößen body mass index (BMI) und fat mass index (FMI) berechnet. Ergebnisse: Die gesamt-KA und moderate bis intensive KA zeigte einen quadratisch abfallenden Verlauf mit steigendem Alter (KA: -75.3 min/Tag, p < 0.001; moderate bis intensive KA: -30.7 min/Tag, p < 0.001). Der Umfang an ST stieg im selben Zeitraum signifikant an (+107min, p = 0.001). Jungen zeigten einen steileren Abfall an leichter KA (p = 0.003) und moderate bis intensive KA (p < 0.001). Ein höheres Niveau an gesamt-KA und moderate bis intensive KA (als unabhängige Variablen im Model) waren durchgehend mit einem niedrigeren BMI und FMI assoziiert, wohingegen mehr ST mit einem höheren BMI und FMI assoziiert war. Bei der Betrachtung von alters-abhängigen Effekte, war zu sehen, dass sich die negativen Assoziationen von KA (p = 0.007) mit BMI und die positiven Assoziationen von ST (p < 0.001) mit BMI mit jedem zusätzlichen Lebensjahr vergrößerten. Schlussfolgerungen: In dieser Arbeit konnte ich zeigen, dass bereits ab dem 6. Lebensjahr die KA abnimmt und ST zunimmt. Geschlechterunterschiede im Intensitätsniveau der KA waren sichtbar. Im Verlauf der Kindheit war ST durchgehend mit einem höheren BMI assoziiert, unabhängig von der KA im selben Zeitraum. Diese Ergebnisse unterstreichen die Notwendigkeit übermäßige Sitzzeiten so früh wie möglich mit Interventionen zu bekämpfen. Ein integrativer Ansatz, bei dem ST durch KA ersetzt wird, erscheint dabei am sinnvollsten. Das Intensitätsniveau der KA sollte sich dabei nicht an den Effekten auf anthropometrische Messgrößen orientieren, sondern an dem Geschlecht der Zielgruppe.Objectives: Daily movement behavior during childhood has a great influence on children’s present and later health status. Higher levels of physical activity (PA) and less time spent in sedentary behavior (SB) during early life are positively associated with activity levels in adulthood. An adequate amount of PA and a reduction of inactivity could contribute to the prevention of childhood overweight and obesity. In this thesis, I investigated PA and SB in children from 6 to 11 years of age to gain a better understanding of the extent of change in PA and SB and its association with anthropometric measures. Subjects/Methods: The data used in this thesis were drawn from the European Childhood Obesity Project trial (CHOP), which was conducted in five European countries. The SenseWear Armband 2 was used to measure PA and SB at the ages of 6, 8 and 11 years. The children’s weight, fat mass and height were assessed at each time point and anthropometric measures body mass index (BMI) and fat mass index (FMI) were calculated. Results: Total PA and moderate-to-vigorous PA (MVPA) showed a significant quadratic decline with age (PA: -75.3 min/day, p < 0.001; MVPA: -30.7 min/day, p < 0.001). The amount of SB increased significantly in the same timeframe (+107min, p = 0.001). Boys showed a steeper decline in light PA (p = 0.003) and MVPA (p < 0.001) than girls. Higher levels of total PA and MVPA (predictor) were consistently associated with lower BMI and FMI (outcome) and higher SB with higher BMI and FMI. When looking at the age dependent effects, negative associations of MVPA (p = 0.007) and positive associations of SB (p < 0.001) with BMI increased with each year of age. In a reversed model, a higher BMI or FMI (predictors) showed a negative association with MVPA and a positive association with SB (outcomes), but no age interactions were found. Conclusions: In this thesis, I showed that PA decreased and SB increased as early as six years. Sex differences in intensity levels of PA were prominent. Throughout childhood, daily SB was consistently associated with a higher BMI, regardless of time spent physical active. These results emphasize the need to tackle SB by activity interventions as early as possible. An integrated approach of reducing SB by replacing it with PA seems appropriate. Based on our results, the choice of intensity of PA in interventions should not be based on effects on anthropometric measures, but rather the sex of the target group

Physical activity of children in the "Childhood Obesity Project" trial

Ziele: Das tägliche Bewegungsverhalten in der Kindheit hat einen großen Einfluss auf die momentane und zukünftige Gesundheit von Kindern. Ein höheres Niveau an körperlicher Aktivität (KA) und weniger Zeit in sitzenden Tätigkeiten (ST) während den ersten Lebensjahren ist positiv mit dem Bewegungsverhalten im Erwachsenenalter assoziiert. Zudem kann ein adäquater Umfang an KA und eine Reduktion von Inaktivität zur Prävention von kindlichem Übergewicht und Adipositas beitragen. In dieser Arbeit untersuche ich sowohl KA als auch ST bei Kindern vom 6. Bis zum 11 Lebensjahr, um ein besseres Verständnis für die Veränderung des Bewegungsverhaltens während der Kindheit zu erhalten. Ein weiteres Ziel ist es, mögliche Assoziationen mit anthropometrischen Messgrößen zu untersuchen. Methoden: Die Daten für diese Arbeit stammen aus der europäischen Childhood Obesity Project Studie (CHOP), die in fünf europäischen Ländern durchgeführt wurde. Der Umfang an KA und ST wurde mit sechs, acht und elf Jahren mit Hilfe des Sensewear Armbands 2 gemessen. Gewicht, Fettmasse und Größe der Kinder wurden den jeweiligen Messzeitpunkt erhoben und die anthropometrische Messgrößen body mass index (BMI) und fat mass index (FMI) berechnet. Ergebnisse: Die gesamt-KA und moderate bis intensive KA zeigte einen quadratisch abfallenden Verlauf mit steigendem Alter (KA: -75.3 min/Tag, p < 0.001; moderate bis intensive KA: -30.7 min/Tag, p < 0.001). Der Umfang an ST stieg im selben Zeitraum signifikant an (+107min, p = 0.001). Jungen zeigten einen steileren Abfall an leichter KA (p = 0.003) und moderate bis intensive KA (p < 0.001). Ein höheres Niveau an gesamt-KA und moderate bis intensive KA (als unabhängige Variablen im Model) waren durchgehend mit einem niedrigeren BMI und FMI assoziiert, wohingegen mehr ST mit einem höheren BMI und FMI assoziiert war. Bei der Betrachtung von alters-abhängigen Effekte, war zu sehen, dass sich die negativen Assoziationen von KA (p = 0.007) mit BMI und die positiven Assoziationen von ST (p < 0.001) mit BMI mit jedem zusätzlichen Lebensjahr vergrößerten. Schlussfolgerungen: In dieser Arbeit konnte ich zeigen, dass bereits ab dem 6. Lebensjahr die KA abnimmt und ST zunimmt. Geschlechterunterschiede im Intensitätsniveau der KA waren sichtbar. Im Verlauf der Kindheit war ST durchgehend mit einem höheren BMI assoziiert, unabhängig von der KA im selben Zeitraum. Diese Ergebnisse unterstreichen die Notwendigkeit übermäßige Sitzzeiten so früh wie möglich mit Interventionen zu bekämpfen. Ein integrativer Ansatz, bei dem ST durch KA ersetzt wird, erscheint dabei am sinnvollsten. Das Intensitätsniveau der KA sollte sich dabei nicht an den Effekten auf anthropometrische Messgrößen orientieren, sondern an dem Geschlecht der Zielgruppe.Objectives: Daily movement behavior during childhood has a great influence on children’s present and later health status. Higher levels of physical activity (PA) and less time spent in sedentary behavior (SB) during early life are positively associated with activity levels in adulthood. An adequate amount of PA and a reduction of inactivity could contribute to the prevention of childhood overweight and obesity. In this thesis, I investigated PA and SB in children from 6 to 11 years of age to gain a better understanding of the extent of change in PA and SB and its association with anthropometric measures. Subjects/Methods: The data used in this thesis were drawn from the European Childhood Obesity Project trial (CHOP), which was conducted in five European countries. The SenseWear Armband 2 was used to measure PA and SB at the ages of 6, 8 and 11 years. The children’s weight, fat mass and height were assessed at each time point and anthropometric measures body mass index (BMI) and fat mass index (FMI) were calculated. Results: Total PA and moderate-to-vigorous PA (MVPA) showed a significant quadratic decline with age (PA: -75.3 min/day, p < 0.001; MVPA: -30.7 min/day, p < 0.001). The amount of SB increased significantly in the same timeframe (+107min, p = 0.001). Boys showed a steeper decline in light PA (p = 0.003) and MVPA (p < 0.001) than girls. Higher levels of total PA and MVPA (predictor) were consistently associated with lower BMI and FMI (outcome) and higher SB with higher BMI and FMI. When looking at the age dependent effects, negative associations of MVPA (p = 0.007) and positive associations of SB (p < 0.001) with BMI increased with each year of age. In a reversed model, a higher BMI or FMI (predictors) showed a negative association with MVPA and a positive association with SB (outcomes), but no age interactions were found. Conclusions: In this thesis, I showed that PA decreased and SB increased as early as six years. Sex differences in intensity levels of PA were prominent. Throughout childhood, daily SB was consistently associated with a higher BMI, regardless of time spent physical active. These results emphasize the need to tackle SB by activity interventions as early as possible. An integrated approach of reducing SB by replacing it with PA seems appropriate. Based on our results, the choice of intensity of PA in interventions should not be based on effects on anthropometric measures, but rather the sex of the target group

Effects of screen time and playing outside on anthropometric measures in preschool aged children

Objective: In view of the current obesity epidemic, studies focusing on the interplay of playing outside (PO), screen time (ST) and anthropometric measures in preschool age are necessary to guide evidence-based public health planning. We therefore investigated the relationship between average time spent PO and ST from the ages 3 to 6 years and anthropometric measures at 6 years of age. Methods PO and ST of 526 children of the European Childhood Obesity Project (CHOP) were annually assessed by questionnaire from 3 until 6 years of age. Body weight, waist circumference and height were measured at 3 and 6 years of age to calculate Body-Mass-Index z-Scores (zBMI) and waist-to-height ratio (WTH). Linear, logistic and quantile regressions were used to test whether average time spent PO and ST in the 4 year period had an effect on anthropometric measures at age 6 years. Results Longer daily ST was associated with a higher zBMI (P = 0.002) and WTH (P = 0.001) at 6 years of age. No significant associations were found for time spent PO. Each additional hour of average ST during the 4 year period resulted in a 66% higher risk of having a zBMI score over 1 (P < 0.001) and almost twice the risk (94% higher risk) of having an zBMI score over 2 (P < 0.001) at 6 years. Conclusions: Excessive ST during preschool age is a risk factor for increased zBMI at 6 years, regardless of time spent PO. Reducing high levels of ST during preschool age, for e.g. at least 1h per week, could help preventing childhood obesity

Longitudinal analysis of physical activity, sedentary behaviour and anthropometric measures from ages 6 to 11 years

Background/Objective: The aim of this study was to examine the effect of physical activity (PA) and sedentary behaviour (SB) on body mass index (BMI) and fat mass index (FMI) in children over the course of five years and identify potential bi-directional associations.Subjects/Methods: Data were drawn from the EU Childhood Obesity Project (CHOP). PA and SB were measured with the SenseWear Armband 2 at the ages of 6 (T1), 8 (T2) and 11 (T3) years. Height and weight were measured and BMI was calculated at each time point, resulting in 1254 complete observations from 600 children. Bio impedance analysis was used to measure body fat mass and eventually calculate FMI. To examine the longitudinal association between PA/SB and BMI/FMI as well as to account for repeated measure on these children, mixed model analysis was employed.Results: Higher levels of total PA and moderate-to-vigorous PA (MVPA) were associated with lower BMI and FMI and higher SB with higher BMI and FMI over the five year period. When looking at the age dependent effects, negative associations of MVPA ((MVPA x age): -0.05, 95% confidence interval (CI): -0.09 - -0.01, p=0.007) and positive associations of SB ((SB x age): 0.04, 95% CI: 0.02-0.06, p<0.001) increased with each year of age. In a model combining these two effects, only SB x age interaction remained significant ((SB x age): 0.04, 95% CI: 0.03-0.06, p=0.01). No significant interaction between MVPA and SB could be discerned. Light Physical activity showed no significant associations with BMI or FMI. When reversing outcome and predictor;higher BMI or FMI showed a negative association with MVPA and a positive association with SB, but no age dependency.Conclusions: More time per day in SB was associated with a higher BMI over the course of five years, whereas higher MVPA had an inverse effect. In a combined model, only effects of higher SB remained significant, emphasizing the importance of SB in obesity prevention. Present bidirectional associations, where lower body size was associated with higher PA and lower SB, indicated the need for an integrated approach of activity and weight control for obesity prevention.Trial registrationClinicalTrials.gov Identifier: NCT00338689. Registered: June 19, 2006 (retrospectively registered)

BMI and recommended levels of physical activity in school children

Background: Physical activity (PA) and its health benefits are a continuous point of discussion. Recommendations for children's daily PA vary between guidelines. To better define the amount of PA necessary to prevent overweight and obesity in children, further research is needed. The present study investigates children's compliance to physical activity guidelines (PAGs) and the association between objectively measured PA and body mass index (BMI). Methods: Participating children were 11 years old (n = 419) and part of the European CHOP trial, which was conducted in Germany, Belgium, Poland, Spain, Italy. At least 2 days of PA measurements were collected from each child using a SenseWear (TM) armband. BMI was calculated from children's height and weight. Thresholds of min.day(-1) in PA needed to differentiate between normal and excess weight (overweight/obesity) were determined with Receiver Operator Characteristics (ROC) analysis. Additionally, adjusted linear and logistic regressions models were calculated for group differences and effects of a 5, 15 and 60 min.day(-1) increases in PA on BMI. Results: Median time spent in total PA was 462 min.day(-1) (25th percentile;75th percentile: 389;534) and 75 min . day(-1) (41;115) in moderate to vigorous PA (MVPA). Girls spent 36 min . day(-1) less in MVPA than boys and overweight/obese children 24 min . day(-1) less than normal weight children (linear regression, p < 0.001). 63.2% of the children met PAGs of 60 min.day(-1) in MVPA. The optimal threshold for min.day(-1) in MVPA determined with ROC analysis was 46 min.day(-1). Comparing 5, 15 and 60 min.day(-1) increases in PA revealed that an additional 15 min.day(-1) of vigorous PA had the same effect as 60 min.day(-1) of MVPA. Sedentary time and light PA showed contrary associations to one another, with light PA being negatively and sedentary time being positively associated with excessive weight. Conclusions: Current PAGs are met by 2/3 of children and seem appropriate to prevent excess weight in children. An official recommendation of daily 15-20 min of vigorous PA and further reduction of sedentary time could help to fight youth overweight and thus be of potential public health importance

Cohort Profile : The DynaHEALTH consortium - a European consortium for a life-course bio-psychosocial model of healthy ageing of glucose homeostasis

Peer reviewe

The LifeCycle Project-EU Child Cohort Network : a federated analysis infrastructure and harmonized data of more than 250,000 children and parents

Early life is an important window of opportunity to improve health across the full lifecycle. An accumulating body of evidence suggests that exposure to adverse stressors during early life leads to developmental adaptations, which subsequently affect disease risk in later life. Also, geographical, socio-economic, and ethnic differences are related to health inequalities from early life onwards. To address these important public health challenges, many European pregnancy and childhood cohorts have been established over the last 30 years. The enormous wealth of data of these cohorts has led to important new biological insights and important impact for health from early life onwards. The impact of these cohorts and their data could be further increased by combining data from different cohorts. Combining data will lead to the possibility of identifying smaller effect estimates, and the opportunity to better identify risk groups and risk factors leading to disease across the lifecycle across countries. Also, it enables research on better causal understanding and modelling of life course health trajectories. The EU Child Cohort Network, established by the Horizon2020-funded LifeCycle Project, brings together nineteen pregnancy and childhood cohorts, together including more than 250,000 children and their parents. A large set of variables has been harmonised and standardized across these cohorts. The harmonized data are kept within each institution and can be accessed by external researchers through a shared federated data analysis platform using the R-based platform DataSHIELD, which takes relevant national and international data regulations into account. The EU Child Cohort Network has an open character. All protocols for data harmonization and setting up the data analysis platform are available online. The EU Child Cohort Network creates great opportunities for researchers to use data from different cohorts, during and beyond the LifeCycle Project duration. It also provides a novel model for collaborative research in large research infrastructures with individual-level data. The LifeCycle Project will translate results from research using the EU Child Cohort Network into recommendations for targeted prevention strategies to improve health trajectories for current and future generations by optimizing their earliest phases of life.Peer reviewe