WHO European Childhood Obesity Surveillance Initiative: health-risk behaviours on nutrition and physical activity in 6-9-year-old schoolchildren.

OBJECTIVE: To assess to what extent eight behavioural health risks related to breakfast and food consumption and five behavioural health risks related to physical activity, screen time and sleep duration are present among schoolchildren, and to examine whether health-risk behaviours are associated with obesity. DESIGN: Cross-sectional design as part of the WHO European Childhood Obesity Surveillance Initiative (school year 2007/2008). Children's behavioural data were reported by their parents and children's weight and height measured by trained fieldworkers. Descriptive statistics and logistic regression analyses were performed. SETTING: Primary schools in Bulgaria, Lithuania, Portugal and Sweden; paediatric clinics in the Czech Republic. SUBJECTS: Nationally representative samples of 6-9-year-olds (n 15 643). RESULTS: All thirteen risk behaviours differed statistically significantly across countries. Highest prevalence estimates of risk behaviours were observed in Bulgaria and lowest in Sweden. Not having breakfast daily and spending screen time ≥2 h/d were clearly positively associated with obesity. The same was true for eating 'foods like pizza, French fries, hamburgers, sausages or meat pies' >3 d/week and playing outside <1 h/d. Surprisingly, other individual unhealthy eating or less favourable physical activity behaviours showed either no or significant negative associations with obesity. A combination of multiple less favourable physical activity behaviours showed positive associations with obesity, whereas multiple unhealthy eating behaviours combined did not lead to higher odds of obesity. CONCLUSIONS: Despite a categorization based on international health recommendations, individual associations of the thirteen health-risk behaviours with obesity were not consistent, whereas presence of multiple physical activity-related risk behaviours was clearly associated with higher odds of obesity.

WHO European Childhood Obesity Surveillance Initiative: associations between sleep duration, screen time and food consumption frequencies.

BACKGROUND: Both sleep duration and screen time have been suggested to affect children's diet, although in different directions and presumably through different pathways. The present cross-sectional study aimed to simultaneously investigate the associations between sleep duration, screen time and food consumption frequencies in children. METHODS: The analysis was based on 10 453 children aged 6-9 years from five European countries that participated in the World Health Organization European Childhood Obesity Surveillance Initiative. Logistic multilevel models were used to assess associations of parent-reported screen time as well as sleep duration (exposure variables) with consumption frequencies of 16 food items (outcome variables). All models were adjusted for age, sex, outdoor play time, maximum educational level of parents and sleep duration or screen time, depending on the exposure under investigation. RESULTS: One additional hour of screen time was associated with increased consumption frequencies of 'soft drinks containing sugar' (1.28 [1.19;1.39]; odds ratio and 99% confidence interval), 'diet/light soft drinks' (1.21 [1.14;1.29]), 'flavoured milk' (1.18 [1.08;1.28]), 'candy bars or chocolate' (1.31 [1.22;1.40]), 'biscuits, cakes, doughnuts or pies' (1.22 [1.14;1.30]), 'potato chips (crisps), corn chips, popcorn or peanuts' (1.32 [1.20;1.45]), 'pizza, French fries (chips), hamburgers'(1.30 [1.18;1.43]) and with a reduced consumption frequency of 'vegetables (excluding potatoes)' (0.89 [0.83;0.95]) and 'fresh fruits' (0.91 [0.86;0.97]). Conversely, one additional hour of sleep duration was found to be associated with increased consumption frequencies of 'fresh fruits' (1.11 [1.04;1.18]) and 'vegetables (excluding potatoes)' (1.14 [1.07;1.23]). CONCLUSION: The results suggest a potential relation between high screen time exposure and increased consumption frequencies of foods high in fat, free sugar or salt whereas long sleep duration may favourably be related to children's food choices. Both screen time and sleep duration are modifiable behaviours that may be tackled in childhood obesity prevention efforts.

WHO European Childhood Obesity Surveillance Initiative: School nutrition environment and body mass index in primary schools.

BACKGROUND: Schools are important settings for the promotion of a healthy diet and sufficient physical activity and thus overweight prevention. OBJECTIVE: To assess differences in school nutrition environment and body mass index (BMI) in primary schools between and within 12 European countries. METHODS: Data from the World Health Organization (WHO) European Childhood Obesity Surveillance Initiative (COSI) were used (1831 and 2045 schools in 2007/2008 and 2009/2010, respectively). School personnel provided information on 18 school environmental characteristics on nutrition and physical activity. A school nutrition environment score was calculated using five nutrition-related characteristics whereby higher scores correspond to higher support for a healthy school nutrition environment. Trained field workers measured children's weight and height; BMI-for-age (BMI/A) Z-scores were computed using the 2007 WHO growth reference and, for each school, the mean of the children's BMI/A Z-scores was calculated. RESULTS: Large between-country differences were found in the availability of food items on the premises (e.g., fresh fruit could be obtained in 12%-95% of schools) and school nutrition environment scores (range: 0.30-0.93). Low-score countries (Bulgaria, Czech Republic, Greece, Hungary, Latvia and Lithuania) graded less than three characteristics as supportive. High-score (≥0.70) countries were Ireland, Malta, Norway, Portugal, Slovenia and Sweden. The combined absence of cold drinks containing sugar, sweet snacks and salted snacks were more observed in high-score countries than in low-score countries. Largest within-country school nutrition environment scores were found in Bulgaria, Czech Republic, Greece, Hungary, Latvia and Lithuania. All country-level BMI/A Z-scores were positive (range: 0.20-1.02), indicating higher BMI values than the 2007 WHO growth reference. With the exception of Norway and Sweden, a country-specific association between the school nutrition environment score and the school BMI/A Z-score was not observed. CONCLUSIONS: Some European countries have implemented more school policies that are supportive to a healthy nutrition environment than others. However, most countries with low school nutrition environment scores also host schools with supportive school environment policies, suggesting that a uniform school policy to tackle the "unhealthy" school nutrition environment has not been implemented at the same level throughout a country and may underline the need for harmonized school policies.

WHO European Childhood Obesity Surveillance Initiative: body mass index and level of overweight among 6-9-year-old children from school year 2007/2008 to school year 2009/2010.

BACKGROUND: The World Health Organization (WHO) Regional Office for Europe has established the Childhood Obesity Surveillance Initiative (COSI) to monitor changes in overweight in primary-school children. The aims of this paper are to present the anthropometric results of COSI Round 2 (2009/2010) and to explore changes in body mass index (BMI) and overweight among children within and across nine countries from school years 2007/2008 to 2009/2010. METHODS: Using cross-sectional nationally representative samples of 6-9-year-olds, BMI, anthropometric Z-scores and overweight prevalence were derived from measured weight and height. Significant changes between rounds were assessed using variance and t-tests analyses. RESULTS: At Round 2, the prevalence of overweight (including obesity; WHO definitions) ranged from 18% to 57% among boys and from 18% to 50% among girls; 6 - 31% of boys and 5 - 21% of girls were obese. Southern European countries had the highest overweight prevalence. Between rounds, the absolute change in mean BMI (range: from -0.4 to +0.3) and BMI-for-age Z-scores (range: from -0.21 to +0.14) varied statistically significantly across countries. The highest significant decrease in BMI-for-age Z-scores was found in countries with higher absolute BMI values and the highest significant increase in countries with lower BMI values. The highest significant decrease in overweight prevalence was observed in Italy, Portugal and Slovenia and the highest significant increase in Latvia and Norway. CONCLUSIONS: Changes in BMI and prevalence of overweight over a two-year period varied significantly among European countries. It may be that countries with higher prevalence of overweight in COSI Round 1 have implemented interventions to try to remedy this situation.