New indices in predicting cardiometabolic risk and its relation to endothelial dysfunction in adolescents: The HELENA study.

BACKGROUND AND AIMS: Blood pressure (BP) changes and insulin resistance (IR) are important cardiometabolic risk (CMR) factors; their early identification can contribute to the reduction of cardiovascular events in adulthood. This necessitates the search for more accessible and easily applied indicators for their prediction. Therefore, this study aimed to evaluate the predictive power of the indices, TyG, TG/HDL-c, height-corrected lipid accumulation product (HLAP), and visceral adiposity index (VAI), in identifying the CMR obtained by high BP and IR and to verify their relationship with biomarkers of endothelial dysfunction (ED) in European adolescents. METHODS AND RESULTS: The anthropometric data and blood biomarkers of 744 adolescents (343 boys and 401 girls) from the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study (HELENA-CSS), with a mean age of 14.67 (SD 1.15) years, were assessed. The adolescents were then classified according to the presence or absence of high BP and IR. The cut-off points of the indices evaluated for the identification of CMR were determined. The relationship between CMR diagnosed using these indices and ED biomarkers was tested. The HLAP and TG/HDL-c were fair predictors of CMR obtained by IR in male adolescents. These indices showed association with hsCRP in sVCAM-1 in boys, but it lost significance after adjusting for age and body mass index. CONCLUSION: TG/HDL-c and HLAP indices showed a fair performance in predicting CMR, obtained by IR, in male adolescents. ED showed no association with the CMR identified by the indices.

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.

Dietary Patterns in European and Brazilian Adolescents: Comparisons and Associations with Socioeconomic Factors.

Associations between dietary patterns (DP) and socioeconomic factors have been little explored in adolescents. The aim of this study was to identify DP in European and Brazilian adolescents and to investigate their associations with a range of socioeconomic indicators. Adolescents from the HELENA-study and the Household Budget Survey were analyzed. Factor analysis was used to obtain DP. Linear regression was used to examine the association between DP and SES. In Europeans, the Western DP was associated with low education of the mother, high socioeconomic status (boys), older age (boys), and living in cities of the Northern Europe; in Brazilians, the Western DP was associated with high secondary education of the mother, high socioeconomic status and living in Southern areas of the country. The Traditional European DP, in both genders, was associated with high secondary education of the mother and inversely associated with a high socioeconomic status; the Traditional Brazilian DP, was associated with university level education of the mother and older age (boys). The association between DP and socioeconomic factors is relevant for the understanding of food-related practices and highlight the importance of performing a complete assessment of the socioeconomic influence in adolescent's DP from developed and developing countries.

More physically active and leaner adolescents have higher energy intake.

OBJECTIVE: To test whether youths who engage in vigorous physical activity are more likely to have lean bodies while ingesting relatively large amounts of energy. For this purpose, we studied the associations of both physical activity and adiposity with energy intake in adolescents. STUDY DESIGN: The study subjects were adolescents who participated in 1 of 2 cross-sectional studies, the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study (n = 1450; mean age, 14.6 years) or the European Youth Heart Study (EYHS; n = 321; mean age, 15.6 years). Physical activity was measured by accelerometry, and energy intake was measured by 24-hour recall. In the HELENA study, body composition was assessed by 2 or more of the following methods: skinfold thickness, bioelectrical impedance analysis, plus dual-energy X-ray absorptiometry or air-displacement plethysmography in a subsample. In the EYHS, body composition was assessed by skinfold thickness. RESULTS: Fat mass was inversely associated with energy intake in both studies and using 4 different measurement methods (P ≤ .006). Overall, fat-free mass was positively associated with energy intake in both studies, yet the results were not consistent across measurement methods in the HELENA study. Vigorous physical activity in the HELENA study (P < .05) and moderate physical activity in the EYHS (P < .01) were positively associated with energy intake. Overall, results remained unchanged after adjustment for potential confounding factors, after mutual adjustment among the main exposures (physical activity and fat mass), and after the elimination of obese subjects, who might tend to underreport energy intake, from the analyses. CONCLUSION: Our data are consistent with the hypothesis that more physically active and leaner adolescents have higher energy intake than less active adolescents with larger amounts of fat mass.

Physical activity, fitness, and serum leptin concentrations in adolescents.

OBJECTIVE: To examine the association of physical activity and fitness with leptin concentrations in European adolescents, after taking into account several potential confounders including total body fat (TBF). STUDY DESIGN: We conducted a cross-sectional study in a school setting for the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study. This study included 902 (509 girls) adolescents aged 12.5-17.5 years. Weight, height, and TBF (sum of 6 skinfold thickness) were measured, and fat free mass and body mass index were calculated. Physical activity was assessed by accelerometry. Physical fitness was assessed by the handgrip, standing long jump, 4 × 10-m shuttle run, and 20-m shuttle run tests. Serum fasting leptin, insulin, and glucose concentrations were measured, and homeostasis model assessment was computed. Multiple linear regression models were used. RESULTS: Vigorous physical activity and fitness tests (all P < .05) were negatively associated with leptin, independently of several confounders including TBF and homeostasis model assessment. These associations remained significant after further controlling for each other (physical activity and fitness). CONCLUSION: These results suggest that vigorous physical activity and fitness moderate the levels of leptin concentrations, regardless of relevant confounders including TBF. Intervention programs addressed to increase high intensity physical activity and fitness as well as to assess its impact on leptin concentration are required.

Are muscular and cardiovascular fitness partially programmed at birth? Role of body composition.

OBJECTIVE: To determine whether birth weight is associated with handgrip strength and cardiovascular fitness in adolescence and, if so, how these associations are influenced by current body composition. STUDY DESIGN: A total of 1801 adolescents (983 females), age 13 to 18.5 years, from the AVENA (Alimentación y Valoración del Estado Nutricional de los Adolescentes Españoles [Food and Assessment of the Nutritional Status of Spanish Adolescents]) study were evaluated. Handgrip strength and cardiovascular fitness were assessed using the handgrip test and the 20-m shuttle run test, respectively. RESULTS: Birth weight was positively associated with handgrip strength in females after controlling for current age, gestational age, breast-feeding, and adolescent body mass index (P = .002), body fat percentage (P < .001), or waist circumference (P = .005), but not after controlling for fat-free mass. The associations were similar yet weaker in males. Females with high birth weight (>90th percentile) had greater handgrip strength than those with normal (10th to 90th percentile) or low (<10th percentile) birth weight, after adjusting for body fat percentage (P = .004). All of the differences became nonsignificant after adjusting for adolescent fat-free mass. Birth weight was not associated with cardiovascular fitness. CONCLUSIONS: High birth weight is associated with greater handgrip strength in adolescents, especially in females, yet these associations seem to be highly explained by fat-free mass.