The association of emotion-driven impulsiveness, cognitive inflexibility and decision-making with weight status in European adolescents.

OBJECTIVE: To explore the association between emotion-driven impulsiveness, cognitive inflexibility, decision-making and weight status as reflected in body mass index (BMI) z-score (zBMI) in European adolescents. METHODS: In total, 3354 adolescents aged between 12 and 18 years from the I.Family cohort completed the questionnaire-based negative urgency subscale from the UPPS-P Impulsive Behavior Scale to measure emotion-driven impulsiveness in 2013/2014. Furthermore, 1584 adolescents completed the computer-based Bergs Card Sorting Test to measure cognitive inflexibility, and 1780 adolescents completed the Hungry Donkey Test to assess decision-making ability. Anthropometric variables were measured objectively; confounding variables (age, sex, socioeconomic status and country) were assessed using a questionnaire. Mixed-effect regression analyses were conducted for each outcome of the test or questionnaire as a predictor with standardised BMI (zBMI) as the dependent variable in order to investigate association between markers of cognitive functioning and zBMI. RESULTS: After controlling for confounders, results showed that emotion-driven impulsiveness (ß=0.18, 95% confidence interval (CI): 0.13 to 0.24, P<0.001) and cognitive inflexibility (ß=0.01, 95% CI: 0.002 to 0.02, P=0.016) were positively associated with zBMI. However, decision-making ability was not significantly related to zBMI (ß=0.001, 95% CI: -0.001 to 0.003, P=0.47). CONCLUSIONS: More emotion-driven impulsiveness and reduced cognitive flexibility were associated with a higher zBMI in adolescents across Europe. These results may indicate that being impulsive in negative situations and having difficulties changing mental sets increase the susceptibility for unhealthy weight development. Reducing impulsivity and training cognitive flexibility seem promising targets for the prevention and intervention programmes of obesity.

Clustering of multiple lifestyle behaviours and its association to cardiovascular risk factors in children: the IDEFICS study.

BACKGROUND/OBJECTIVES: Individual lifestyle behaviours have independently been associated with cardiovascular diseases (CVD) risk factors in children. This study aimed to identify clustered lifestyle behaviours (dietary, physical activity (PA) and sedentary indicators) and to examine their association with CVD risk factors in children aged 2-9 years. SUBJECTS/METHODS: Participants included 4619 children (51.6% boys) from eight European countries participating in the IDEFICS cross-sectional baseline survey (2007-2008). Insulin resistance, total cholesterol/high-density lipoprotein cholesterol ratio, triglycerides, sum of two skinfolds and systolic blood pressure (SBP) z-scores were summed to compute a CVD risk score. Cluster analyses stratified by sex and age groups (2 to <6 years; 6-9 years) were performed using parental-reported data on fruit, vegetables and sugar-sweetened beverages (SSB) consumption, PA performance and television video/DVD viewing. RESULTS: Five clusters were identified. Associations between CVD risk factors and score, and clusters were obtained by multiple linear regression using cluster 5 ('low beverages consumption and low sedentary') as the reference cluster. SBP was positively associated with clusters 1 ('physically active'; ß=1.34; 95% confidence interval (CI): 0.02, 2.67), 2 ('sedentary'; ß=1.84; 95% CI: 0.57, 3.11), 3 ('physically active and sedentary'; ß=1.45; 95% CI: 0.15, 2.75) and 4 ('healthy diet'; ß=1.83; 95% CI: 0.50, 3.17) in older boys. A positive association was observed between CVD risk score and clusters 2 (ß=0.60; 95% CI: 0.20, 1.01), 3 (ß=0.55; 95% CI: 0.14, 0.97) and 4 (ß=0.60, 95% CI: 0.18, 1.02) in older boys. CONCLUSIONS: Low television/video/DVD viewing levels and low SSB consumption may result in a healthier CVD profile rather than having a diet rich in fruits and vegetables or being physically active in (pre-)school children.

Intra- and inter-observer reliability in anthropometric measurements in children.

INTRODUCTION: Studies such as IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) seek to compare data across several different countries. Therefore, it is important to confirm that body composition indices, which are subject to intra- and inter-individual variation, are measured using a standardised protocol that maximises their reliability and reduces error in analyses. OBJECTIVE: To describe the standardisation and reliability of anthropometric measurements. Both intra- and inter-observer variability of skinfold thickness (triceps, subscapular, biceps, suprailiac) and circumference (neck, arm, waist, hip) measurements were investigated in five different countries. METHODS: Central training for fieldwork personnel was carried out, followed by local training in each centre involving the whole survey staff. All technical devices and procedures were standardised. As part of the standardisation process, at least 20 children participated in the intra- and inter-observer reliability test in each centre. A total of 125 children 2-5 years of age and 164 children 6-9 years of age took part in this study, with a mean age of 5.4 (± 1.2) years. RESULTS: The intra-observer technical error of measurement (TEM) was between 0.12 and 0.47 mm for skinfold thickness and between 0.09 and 1.24 cm for circumference measurements. Intra-observer reliability was 97.7% for skinfold thickness (triceps, subscapular, biceps, suprailiac) and 94.7% for circumferences (neck, arm, waist, hip). Inter-observer TEMs for skinfold thicknesses were between 0.13 and 0.97 mm and for circumferences between 0.18 and 1.01 cm. Inter-observer agreement as assessed by the coefficient of reliability for repeated measurements of skinfold thickness and circumferences was above 88% in all countries. CONCLUSION: In epidemiological surveys it is essential to standardise the methodology and train the participating staff in order to decrease measurement error. In the framework of the IDEFICS study, acceptable intra- and inter-observer agreement was achieved for all the measurements.