Association between CNTF Polymorphisms and Adiposity Markers in European Adolescents.

OBJECTIVE: To examine the association between polymorphisms of the ciliary neurotrophic factor gene (CNTF) and total and central adiposity markers in adolescents. STUDY DESIGN: This cross-sectional study involved 1057 European adolescents aged 12-18 years enrolled in the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study. Five polymorphisms of CNTF were genotyped, and the weight, height, waist and hip circumference, and triceps and subscapular skinfold thickness of the subjects were measured and recorded. RESULTS: The T allele of rs2509914, the C allele of rs2515363, and the G allele of rs2515362 were significantly associated (after Bonferroni correction) with higher values for several adiposity markers under different inheritance models. The CNTF CCGGA haplotype (rs2509914, rs17489568, rs2515363 rs1800169, and rs2515362) was also significantly associated with lower body mass index, waist circumference, waist/height ratio, and waist/hip ratio values compared with the TCCGG haplotype under several inheritance models. CONCLUSIONS: Three polymorphisms-rs2509914, rs2515363, and rs2515362-and the CCGGA haplotype of CNTF were significantly associated with adiposity in European adolescents. These results suggest the potential role of CTNF in the development of obesity-related phenotypes.

How do energy balance-related behaviors cluster in adolescents?

OBJECTIVES: To delineate the clustering of energy balance-related behaviors in adolescents and investigate whether these behaviors are associated with the household socioeconomic status and parental education level. METHODS: Two cross-sectional studies assessed information on sedentary behavior, physical activity, sugar-sweetened beverages and fruit and vegetable consumption, and sleep duration by self-reported questionnaires in adolescents (12.5-17.5 years old) from Maringá/Brazil (BRACAH Study; n = 682) and ten European cities (HELENA Study; n = 1252) from nine different countries. Gender-specific cluster analyses were performed separately for each study, applying a combination of hierarchical and non-hierarchical methods. RESULTS: Girls showed equivalent behaviors: Sedentary; Active; Unhealthy Eating; Healthy Eating; while boys differed (Brazilian: Sedentary; Active; Healthy Eating; European: Sedentary; Healthy; Unhealthy Eating). In Brazil, we found no association between socioeconomic status and parental education. In European girls, the high socioeconomic status and both parents' university degree were associated with Healthy Eating. In European boys, the high socioeconomic status was associated with Unhealthy Eating, and the mothers' university degree was associated with the Healthy cluster. CONCLUSIONS: Adolescents show Sedentary behavior, regardless of their sex, country of origin, or socioeconomic condition.

Measuring nutritional knowledge using Item Response Theory and its validity in European adolescents.

OBJECTIVE: To analyse the Nutritional Knowledge Test (NKT) using Item Response Theory (ITR) analysis and to assess the construct validity of the Nutritional Knowledge Scale (NKTS) and its associations with adolescent food group consumption and nutritional biomarkers. DESIGN: Cross-sectional study. SETTING: Multicentre investigation conducted in ten European cities.ParticipantsAdolescents aged 12·5-17·5 years (n 3215) who completed over 75 % of the NKT. RESULTS: Factor analysis indicated that the NKT can be analysed with a one-dimensional model. Eleven out of twenty-three items from the NKT presented adequate parameters and were selected to be included in the NKTS. Nutrition knowledge was positively associated with consumption of fruits, cereals, dairy products, pulses, meat and eggs, and fish, as well as with blood concentrations of vitamin C, ß-carotene, n-3 fatty acids, holo-transcobalamin, cobalamin and folate; nutrition knowledge was negatively associated with intake of olives and avocado, alcohol and savoury snacks. CONCLUSIONS: The NKTS assessed nutritional knowledge adequately and it is proposed as a new tool to investigate this subject in future studies.

Does the Mediterranean Diet Protect against Stress-Induced Inflammatory Activation in European Adolescents? The HELENA Study.

Stress increases inflammation but whether adherence to Mediterranean diet counteracts this association and how early can these effects be observed is not well known. We tested whether (1) cortisol is associated to inflammation, (2) cortisol is associated to the adolescent Mediterranean diet score (aMDS), (3) aMDS lessens inflammation, (4) aMDS associates with cortisol levels and inflammation. Two hundred and forty-two adolescents (137 females; 12.5⁻17.5 years old) provided salivary cortisol, blood and 2-day 24-h dietary recall from which aMDS was derived. Cortisol levels were associated with increased tumor necrosis factor (TNF-α B = 11.887, p = 0.001) when adjusted for age, gender, parental education and body mass index (BMI). Moreover, cortisol levels were inversely associated to adherence to the Mediterranean Diet (B = -1.023, p = 0.002). Adolescents with higher adherence to aMDS had lower levels of interleukins (IL) IL-1, IL-2, IL-6 and TNF-α, compared to those who did not adhere. The association between cortisol and TNF-α was no longer significant when aMDS was included in the model (B = 6.118, p = 0.139). In addition, comparing lower and higher aMDS groups, the association between cortisol and TNF-α was only observed in those with lower aMDS adherence. Our study suggests that adherence to the Mediterranean Diet may counteract the effect of stress on inflammatory biomarkers which may contribute to decreasing the risk of future mental health.

Physical Fitness and Metabolic Syndrome in Children with Repaired Congenital Heart Disease Compared with Healthy Children.

OBJECTIVE: To determine whether children who underwent surgery for congenital heart disease (CHD) are as fit as their peers. STUDY DESIGN: We studied 66 children (6-14 years) who underwent surgery for ventricular septal defect (n = 19), coarctation of aorta (n = 10), tetralogy of Fallot (n = 15), and transposition of great arteries (n = 22); and 520 healthy children (6-12 years). All children performed physical fitness tests: cardiorespiratory fitness, muscular strength, balance, flexibility, and speed. Metabolic score was assessed through z-score standardization using 4 components: waist circumference, blood pressure, blood lipids, and insulin resistance. Assessment also included self-reported and accelerometer-measured physical activity. Linear regression analyses with group (CHD vs control) as a predictor were adjusted for age, body mass index, physical activity, and parental education. RESULTS: Measured physical activity level, body mass index, cardiorespiratory fitness, flexibility, and total metabolic score did not differ between children with CHD and controls, whereas reported physical activity was greater in the CHD group than control group. Boys with CHD were less strong in upper muscular strength, speed, and balance, whereas girls with CHD were better in lower muscular strength and worse in balance. High-density lipoprotein was greater in boys and girls with CHD, whereas boys with CHD showed unhealthier glucose homeostasis. CONCLUSION: Appropriate physical fitness was achieved in children after surgery for CHD, especially in girls. Consequently, children with CHD were not at increased total metabolic risk. Lifestyle counseling should be part of every patient interaction.