Association of physical activity with adiposity in preschoolers using different clinical adiposity measures: a cross-sectional study.

BACKGROUND: More research is needed about the association between physical activity (PA), sedentary behaviour (SB), and adiposity in preschoolers, particularly using more direct clinical measures of adiposity. Therefore, the main objective of this study was to investigate the association between objectively measured PA and different clinical adiposity measures in a large sample of preschoolers. METHODS: Four hundred sixty-three predominantly normal-weight (77%) 2-6-year-old preschool children participated in the Swiss Preschoolers' Health Study (SPLASHY). Physical activity was measured using accelerometers and was analyzed using 15-s (uni-axial) epoch length using validated cut-offs. Adiposity measures included body mass index (BMI), the sum of four skinfolds, and waist circumference (WC). Multilevel linear regression modeling, adjusted for age, sex and wear time, was used to assess the association between PA and SB with BMI, WC, and skinfold thickness. RESULTS: Total PA and different PA intensities were positively and SB was inversely associated with BMI in the total sample and in the normal-weight children (p < 0.05). Total PA was inversely associated with skinfold thickness in overweight and obese children (p < 0.05), while there was only a weak association for vigorous PA (p > 0.05). Moderate and moderate-to-vigorous PA were positively, and SB was negatively associated with WC in the total sample and in the normal-weight children (p < 0.05). Additional adjustment for potential sociocultural and biological confounding variables attenuated some of the results. CONCLUSIONS: In this very young and predominantly normal-weight population, PA is positively related to BMI and WC, but this relationship is not observed in overweight and obese children. In this latter population, PA is inversely, and SB is positively related to skinfold thickness. Skinfold thickness could represent a useful and simple clinical measure of body fat in preschoolers. The role of vigorous PA in the prevention of early childhood obesity should be further investigated in future studies. TRIAL REGISTRATION: ISRCTN ISRCTN41045021 . Retrospectively registered 06 May 2014.

International Comparison of the Levels and Potential Correlates of Objectively Measured Sedentary Time and Physical Activity among Three-to-Four-Year-Old Children.

Physical activity (PA) patterns track from childhood through to adulthood. The study aimed to determine the levels and correlates of sedentary time (ST), total PA (TPA), and moderate-to-vigorous PA (MVPA) in preschool-aged children. We conducted cross-sectional analyses of 1052 children aged three-to-four-years-old from six studies included in the International Children's Accelerometry Database. Multilevel linear regression models adjusting for age, gender, season, minutes of wear time, and study clustering effects were used to estimate associations between age, gender, country, season, ethnicity, parental education, day of the week, time of sunrise, time of sunset, and hours of daylight and the daily minutes spent in ST, TPA, and MVPA. Across the UK, Switzerland, Belgium, and the USA, children in our analysis sample spent 490 min in ST per day and 30.0% and 21.2% of children did not engage in recommended daily TPA (≥180 min) and MVPA (≥60 min) guidelines. There was evidence for an association between all 10 potential correlates analyzed and at least one of the outcome variables; average daily minutes spent in ST, TPA and/or MVPA. These correlates can inform the design of public health interventions internationally to decrease ST and increase PA in preschoolers.

Prevalence and Predictors of Behavioral Problems in Healthy Swiss Preschool Children Over a One Year Period.

Behavioral problems impair children's health but prevalence rates are scarce and persistence rates vary due to divergence in age ranges, assessment methods and varying environmental factors. The aim of this study was to assess prevalence rates of behavioral problems, their persistence over a 1-year period, and the impact of child- and parent-related factors on behavioral problems. 555 2-6-year-old healthy preschool children were assessed at baseline and 382 of the initial sample at 1-year follow-up. Assessment included questionnaires concerning behavioral problems and their potential predictors (e.g. socio-economic status or parenting style). Altogether, nearly 7% of these children showed clinically relevant behavioral problems, and 3% showed persistent symptoms. Low SES, inconsistent parenting and corporal punishment were positively associated with behavioral problems. The prevalence rates of behavioral problems in Swiss preschoolers are similar to other European countries, but persistence is still rather low within preschool age. These findings need further confirmation in longitudinal studies.

Physical activity and sedentary behavior in preschoolers: a longitudinal assessment of trajectories and determinants.

BACKGROUND: Despite physical activity (PA) being recognized as a critically important factor for good physical and mental health already early in life and throughout the life course, prospective data on activity behavior during the preschool years remains scarce. This study examined trajectories and determinants of levels and change in total PA (TPA), moderate-to-vigorous PA (MVPA) and sedentary behavior (SB) in a representative sample of Swiss preschoolers. METHODS: Data were drawn from the Swiss Preschoolers' Health Study (SPLASHY), a multi-site prospective cohort study including 555 children (53% boys) aged 2-to-6 years at baseline. A follow-up was conducted after 12 months. Activity behavior was measured using accelerometers. Information on 35 potential determinants from different socio-ecological domains was either directly measured or parent-reported. Trajectories of TPA, MVPA and SB over time were described for boys and girls. Linear mixed models were used to investigate factors that predicted levels and change in TPA, MVPA and SB. RESULTS: All children were sufficiently physically active according to published recommendations for preschoolers. Trajectory profiles revealed a marked increase in TPA and MVPA in boys and girls whereas SB remained fairly stable over time. Mixed modeling demonstrated that variables most relevant to determining PA levels were sex, age and activity temperament (all positively associated). Together with gross motor skills, birth weight, family structure (only for TPA) and season (only for MVPA), these factors accounted for 26 and 32% of total variance explained in TPA and MVPA, respectively. Activity temperament emerged as the strongest determinant of SB (negative association) and explained with sex, season and family structure 20% of total variance in SB. The presence of older siblings was the only factor that predicted change in PA over time. CONCLUSIONS: In this healthy physically active cohort of preschoolers, non-modifiable individual-level factors had the greatest influence on PA. The limited success of this and previous studies to identify modifiable determinants and the finding that most preschoolers were sufficiently active suggest that future attempts should provide insights into how preschoolers' activity levels can be maintained and fostered to prevent subsequent harmful declines attributable, amongst others, to educational transitions. Thus, good-quality longitudinal studies are needed. TRIAL REGISTRATION: Current Controlled Trials ISRCTN41045021 (date of registration: 21.03.14).

Impact of age, sex, socioeconomic status, and physical activity on associated movements and motor speed in preschool children.

INTRODUCTION: Young children generally show contralateral associated movements (CAMs) when they are making an effort to perform a unimanual task. CAM and motor speed are two relevant aspects of motor proficiency in young children. These CAMs decrease over age, while motor speed increases. As both CAM and motor speed are associated with age, we were interested in whether these two parameters are also linked with each other. METHOD: In this study, three manual dexterity tasks with the dominant and nondominant hands (pegboard, repetitive hand, and repetitive finger tasks) were used to investigate the effect of covariates (age, sex, socioeconomic status, total physical activity) on both motor speed and CAMs in preschool children. RESULTS: There was a significant age effect for both motor speed and CAMs in all tasks when the dominant hand was used. When the nondominant hand was used, the decrease in the intensity of CAMs over age was not consistently significant. The influence of physical activity and socioeconomic status on motor proficiency was small. Furthermore, the correlation between motor speed and CAMs, although significant, was low. CONCLUSIONS: Motor speed improved with age over three fine motor tasks in preschool children. Decrease in CAMs was observed but it was not always significant when the nondominant hand was working. Motor speed and CAMs were only weakly associated. We conclude that the excitatory pathways responsible for motor speed and inhibitory pathways responsible for reducing CAMs occupy two different domains in the brain and therefore mostly behave independently of each other.

Harmonising data on the correlates of physical activity and sedentary behaviour in young people: Methods and lessons learnt from the international Children's Accelerometry database (ICAD).

BACKGROUND: Large, heterogeneous datasets are required to enhance understanding of the multi-level influences on children's physical activity and sedentary behaviour. One route to achieving this is through the pooling and co-analysis of data from multiple studies. Where this approach is used, transparency of the methodology for data collation and harmonisation is essential to enable appropriate analysis and interpretation of the derived data. In this paper, we describe the acquisition, management and harmonisation of non-accelerometer data in a project to expand the International Children's Accelerometry Database (ICAD). METHOD: Following a consultation process, ICAD partners were requested to share accelerometer data and information on selected behavioural, social, environmental and health-related constructs. All data were collated into a single repository for cataloguing and harmonisation. Harmonised variables were derived iteratively, with input from the ICAD investigators and a panel of invited experts. Extensive documentation, describing the source data and harmonisation procedure, was prepared and made available through the ICAD website. RESULTS: Work to expand ICAD has increased the number of studies with longitudinal accelerometer data, and expanded the breadth of behavioural, social and environmental characteristics that can be used as exposure variables. A set of core harmonised variables, including parent education, ethnicity, school travel mode/duration and car ownership, were derived for use by the research community. Guidance documents and facilities to enable the creation of new harmonised variables were also devised and made available to ICAD users. An expanded ICAD database was made available in May 2017. CONCLUSION: The project to expand ICAD further demonstrates the feasibility of pooling data on physical activity, sedentary behaviour and potential determinants from multiple studies. Key to this process is the rigorous conduct and reporting of retrospective data harmonisation, which is essential to the appropriate analysis and interpretation of derived data. These documents, made available through the ICAD website, may also serve as a guide to others undertaking similar projects.

Association between maternal education and objectively measured physical activity and sedentary time in adolescents.

BACKGROUND: Investigating socioeconomic variation in physical activity (PA) and sedentary time is important as it may represent a pathway by which socioeconomic position (SEP) leads to ill health. Findings on the association between children's SEP and objectively assessed PA and/or sedentary time are mixed, and few studies have included international samples. OBJECTIVE: Examine the associations between maternal education and adolescent's objectively assessed PA and sedentary time. METHODS: This is an observational study of 12 770 adolescents (10-18 years) pooled from 10 studies from Europe, Australia, Brazil and the USA. Original PA data were collected between 1997 and 2009. The associations between maternal education and accelerometer variables were examined using robust multivariable regression, adjusted for a priori confounders (ie, body mass index, monitor wear time, season, age and sex) and regression coefficients combined across studies using random effects meta-analyses. Analyses were conducted in March 2014. RESULTS: Adolescents of university educated mothers spent more time sedentary (9.5 min/day, p=0.005) and less time in light activity (10 min/day, p<0.001) compared with adolescents of high school educated mothers. Pooled analysis across two studies from Brazil and Portugal (analysed separately because of the different coding of maternal education) showed that children of higher educated mothers (tertiary vs primary/secondary) spent less time in moderate to vigorous PA (MVPA) (6.6 min/day, p=0.001) and in light PA (39.2 min/day: p<0.001), and more time sedentary (45.9 min/day, p<0.001). CONCLUSIONS: Across a number of international samples, adolescents of mothers with lower education may not be at a disadvantage in terms of overall objectively measured PA.

Regional differences of physical activity and sedentary behaviour in Swiss children are not explained by socio-demographics or the built environment.

OBJECTIVE: We evaluated whether regional differences in physical activity (PA) and sedentary behaviour (SB) existed along language boundaries within Switzerland and whether potential differences would be explained by socio-demographics or environmental characteristics. METHODS: We combined data of 611 children aged 4 to 7 years from four regional studies. PA and SB were assessed by accelerometers. Information about the socio-demographic background was obtained by questionnaires. Objective neighbourhood attributes could be linked to home addresses. Multivariate regression models were used to test associations between PA and SB and socio-demographic characteristics and neighbourhood attributes. RESULTS: Children from the German compared to the French-speaking region were more physically active and less sedentary (by 10-15 %, p < 0.01). Although German-speaking children lived in a more favourable environment and a higher socioeconomic neighbourhood (differences p < 0.001), these characteristics did not explain the differences in PA behaviour between French and German speaking. CONCLUSIONS: Factors related to the language region, which might be culturally rooted were among the strongest correlates of PA and SB among Swiss children, independent of individual, social and environmental factors.

Long-term effect of a school-based physical activity program (KISS) on fitness and adiposity in children: a cluster-randomized controlled trial.

BACKGROUND: School-based intervention studies promoting a healthy lifestyle have shown favorable immediate health effects. However, there is a striking paucity on long-term follow-ups. The aim of this study was therefore to assess the 3 yr-follow-up of a cluster-randomized controlled school-based physical activity program over nine month with beneficial immediate effects on body fat, aerobic fitness and physical activity. METHODS AND FINDINGS: Initially, 28 classes from 15 elementary schools in Switzerland were grouped into an intervention (16 classes from 9 schools, n = 297 children) and a control arm (12 classes from 6 schools, n = 205 children) after stratification for grade (1st and 5th graders). Three years after the end of the multi-component physical activity program of nine months including daily physical education (i.e. two additional lessons per week on top of three regular lessons), short physical activity breaks during academic lessons, and daily physical activity homework, 289 (58%) participated in the follow-up. Primary outcome measures included body fat (sum of four skinfolds), aerobic fitness (shuttle run test), physical activity (accelerometry), and quality of life (questionnaires). After adjustment for grade, gender, baseline value and clustering within classes, children in the intervention arm compared with controls had a significantly higher average level of aerobic fitness at follow-up (0.373 z-score units [95%-CI: 0.157 to 0.59, p = 0.001] corresponding to a shift from the 50th to the 65th percentile between baseline and follow-up), while the immediate beneficial effects on the other primary outcomes were not sustained. CONCLUSIONS: Apart from aerobic fitness, beneficial effects seen after one year were not maintained when the intervention was stopped. A continuous intervention seems necessary to maintain overall beneficial health effects as reached at the end of the intervention. TRIAL REGISTRATION: ControlledTrials.com ISRCTN15360785.

Socio-cultural determinants of adiposity and physical activity in preschool children: a cross-sectional study.

BACKGROUND: Both individual socio-cultural determinants such as selected parental characteristics (migrant background, low educational level and workload) as well as the regional environment are related to childhood overweight and physical activity (PA). The purpose of the study was to compare the impact of distinct socio-cultural determinants such as the regional environment and selected parental characteristics on adiposity, PA and motor skills in preschool children. METHODS: Forty preschools (N = 542 children) of two culturally different urban regions (German and French speaking part of Switzerland) participated in the study (Ballabeina Study). Outcome measures included adiposity (BMI and skinfold thickness), objectively measured sedentary activities and PA (accelerometers) and agility performance (obstacle course). Parental characteristics (migrant status, educational level and workload) were assessed by questionnaire. RESULTS: Children from the French speaking areas had higher adiposity, lower levels of total and of more intense PA, were more sedentary and less agile than children from the German speaking regions (percent differences for all outcome parameters except for BMI ≥10%; all p ≤ 0.04). Differences in skinfold thickness, sedentary activities and agility, but not in PA, were also found between children of Swiss and migrant parents, though they were ≤8% (p ≤ 0.02). While paternal workload had no effect, maternal workload and parental education resulted in differences in some PA measures and/or agility performance (percent differences in both: ≤9%, p ≤ 0.008), but not in adiposity or sedentary activities (p = NS). Regional differences in skinfold thickness, PA, sedentary activities and agility performance persisted after adjustment for parental socio-cultural characteristics, parental BMI and, where applicable, children's skinfolds (all p ≤ 0.01). CONCLUSIONS: The regional environment, especially the broader social environment, plays a prominent role in determining adiposity, PA and motor skills of young children and should be implicated in the prevention of obesity and promotion of PA in children. TRIAL REGISTRATION: clinicaltrials.gov NCT00674544.

Perceived discrimination against diabetics in the workplace and in work-related insurances in Switzerland.

BACKGROUND: To investigate the prevalence and risk factors of perceived diabetes-related discrimination in the workplace and in work-related insurances in persons with diabetes mellitus in Switzerland. METHODS: 509 insulin-treated diabetic subjects representative of the northwestern Swiss population responded to a self-report questionnaire on perceived diabetes-related discrimination in the workplace and in work-related insurances (salary loss insurance, supplementary occupational plan). Discrimination was defined as being treated differently at least once in relation to diabetes. RESULTS: The reported rates of different aspects of discrimination in the workplace and in work-related insurances ranged between 5-11% and 4-15% respectively. Risk factors that independently increased the risk of not being hired due to diabetes were the presence of at least two severe hypoglycaemic events/year and relevant diabetic complications (OR 5.6 and OR 2.6 respectively; both<0.05). The presence of at least two severe hypoglycaemic events/year was also associated with an increased risk of losing one's job (OR 6.5, <0.01). Overweight or obesity were related to increased discrimination in work-related insurances (OR for denial 2.1-2.4; OR for reserve 3.9-4.4; all<0.05). CONCLUSIONS: Perceived diabetes-related discrimination in the workplace and by work-related insurances is a common problem. In the light of our findings the introduction of effective non-discrimination legislation for patients with chronic illnesses appears to be desirable.

Using insulin pen needles up to five times does not affect needle tip shape nor increase pain intensity.

AIMS: Reusing insulin pen needles could help to reduce the increasing economic burden of diabetes. We tested the hypothesis that reusing insulin pen needles leads to needle tip deformity and increased pain. METHODS: Three blinded reviewers assessed 123 electron microscope pictures analyzing needle tip deformity of insulin pen needles used up to four times by diabetic subjects and up to five times by blinded non-diabetic volunteers. The estimated frequency of needle use was correlated to the actual number of needle use. Pain intensity and unpleasantness of each injection were measured by a visual analogue scale and their differences analyzed by Kruskal-Wallis analysis of variance. RESULTS: Unused needles could be differentiated visually from used needles. However, there was no correlation between the actual and guessed number of times a needle was used (r = 0.07, P = 0.2). Evaluating all 270 injections, neither pain intensity nor unpleasantness increased with repeated injections of the same needles in people with diabetes (P = 0.1 and 0.96) and in the volunteers (P = 0.63 and 0.92). CONCLUSIONS: Using pen needles four to five times does not lead to progressive needle tip deformity and does not increase pain intensity or unpleasantness, but could increase convenience and lead to substantial financial savings in Europe of around EUR 100 million/year.