Tara Rendo-Urteaga

Il6 gene promoter polymorphism (-174G/C) influences the association between fat mass and cardiovascular risk factors.

During the last decades, the prevalence of obesity has increased rapidly among young people. A polymorphism in the promoter region of the IL6 gene (-174G/C), has been previously reported to be involved in obesity and metabolic syndrome development. Therefore, the aim of the study was to examine whether the IL6-174G/C polymorphism influence the association of body fat with low-grade inflammatory markers and blood lipids and lipoproteins in Spanish adolescents. 504 Spanish adolescents participating in the AVENA study were genotyped for the-174G/C polymorphism of the IL6 gene. Anthropometric and body composition measurements were taken and blood samples were collected for plasma molecules determinations. No differences between genotypes were observed in anthropometric values, body composition measurements and plasma markers concentration. Physical activity level differ between genotypes with subjects carrying the C allele of the polymorphism being significantly (p<0.05) more active than GG subjects. The association between body fat mass and plasma glucose was influenced by the -174G/C polymorphism of the IL6 gene. Subjects carrying the C allele of the mutation seem to have higher values of lipoprotein (a) and C-reactive protein as their percentage of body fat mass increase. Our results suggest that this promoter polymorphism influences the association between adiposity and some plasma markers.

Design of the nutritional therapy for overweight and obese Spanish adolescents conducted by registered dieticians: the EVASYON study

BACKGROUND Dietary treatment for obese adolescents should aim to ensure adequate growth and development, by reducing excessive fat mass accumulation, avoiding loss of lean body mass, improving well-being and self-esteem and preventing cyclical weight regain. The aim of this article is to describe the dietary intervention design and the methods used to evaluate nutritional knowledge and behavior in the EVASYON study (Development, implementation and evaluation of the efficacy of a therapeutic programme for overweight/obese adolescents). METHODS/DESIGN EVASYON is a multi-centre study conducted in 5 Spanish hospital settings (Granada, Madrid, Pamplona, Santander and Zaragoza), where 204 overweight/obese Spanish adolescents were treated in groups of 9 to 11 subjects over 20 visits. The study was implemented in two stages: an intensive, calorie-restricted period for the first 9 weeks, and an extensive body-weight follow-up period for the last 11 months. A moderate energy intake restriction was applied in the intensive period according to the degree of obesity, on the basis of a balanced diet supplying 50-55% of daily energy as carbohydrates; 30-35% as fats and 10-15% as proteins. In the intensive period, adolescents were prescribed both a fixed full-day meal plan for the first three weeks and a full day meal plan with different food-choices for 6 weeks. Later, adolescents received a flexible meal plan based on food exchanges for the follow-up period until the end of the trial. Data on food intake, dietary and meal-related habits and behavior were collected by means of dietary questionnaires. To analyse nutritional knowledge, adolescents were examined regarding nutrient concepts and food adoitems for a healthy diet with the appropriate tools. Participants were given nutritional information with complementary teaching material, which was available on the EVASYON website (www.estudioevasyon.com). DISCUSSION The dietary intervention of the EVASYON programme with a moderate calorie restriction for a limited period of time could be a good strategy in treating overweight and obese adolescents and that will be tested further. Moreover, combining fixed plan with free-choice menus may help adolescents and their families to make right decisions for every day meals.

Decreased cardiotrophin-1 levels are associated with a lower risk of developing the metabolic syndrome in overweight/obese children after a weight loss program

OBJECTIVE Cardiotrophin-1 (CT-1) shares some similarities with other cytokines, and participates in the control of energy metabolism. Higher circulating levels are observed in obese humans, but little information is gathered in weight loss (WL) programs. Therefore, we aimed to investigate the association of serum CT-1 levels with metabolic variables and the risk of developing metabolic syndrome (MetS) after a WL program in overweight/obese children. SUBJECTS AND METHODS Forty-four overweight/obese children (mean age 11.5 y; 50% males) undergoing a 10-week WL program were enrolled. Subjects were dichotomized at the median of Body Mass Index-Standard Deviation Score (BMI-SDS) change, as high and low responders after intervention. RESULTS CT-1 levels were significantly reduced (-48 fmol/mL, p=0.043) in the high responder group after the WL program. They had significantly lower body weight (-3.7 kg, p<0.001), body fat mass (-8%, p<0.001), BMI-SDS (-0.78, p<0.001) and waist circumference (-5.4 cm, p<0.001), and a significant improvement in lipid and glucose profiles (p<0.05). Interestingly, decreased CT-1 levels significantly predicted changes in total cholesterol (41%) and LDL-cholesterol (28%). Moreover, in our participants the lower the CT-1 levels, the higher the reduction in MetS risk components, after the 10-week intervention, (p-ANCOVA=0.040, p-trend=0.024). CONCLUSION We showed, for the first time, a reduction in serum CT-1 levels after a WL program and this decrease in CT-1 was strongly associated with a reduction in cholesterol levels and in MetS risk factors in overweight/obese children. Our findings may suggest that CT-1 could be an indirect marker for the diagnosis of MetS in this population.

Validity and reliability of sleep time questionnaires in children and adolescents: A systematic review and meta-analysis

Sleep duration has been associated with several health outcomes in children and adolescents. As an extensive number of questionnaires are currently used to investigate sleep schedule or sleep time, we performed a systematic review of criterion validation of sleep time questionnaires for children and adolescents, considering accelerometers as the reference method. We found a strong correlation between questionnaires and accelerometers for weeknights and a moderate correlation for weekend nights. When considering only studies performing a reliability assessment of the used questionnaires, a significant increase in the correlations for both weeknights and weekend nights was observed. In conclusion, moderate to strong criterion validity of sleep time questionnaires was observed; however, the reliability assessment of the questionnaires showed strong validation performance.

Serum and gene expression levels of CT‐1, IL‐6, and TNF‐α after a lifestyle intervention in obese children

Inflammation related molecules such as tumor necrosis factor‐α (TNF‐α), interleukin 6 (IL‐6), and cardiotrophin‐1 (CT‐1) are highly expressed in obese individuals and could partly explain some comorbidities associated to obesity. In obese children, lifestyle interventions are able to lower inflammation and reduce cardiovascular risk factors associated with obesity. The aim of the present work was to study changes in inflammation‐related molecules serum and peripheral blood mononuclear cells (PBMC) transcript levels after a 10‐week lifestyle intervention in obese children and asses their potential association with glucose metabolism.

Role of fruits and vegetables in adolescent cardiovascular health: a systematic review

Context Levels of fruit and vegetable consumption are low among adolescents, and the possible effect of this on cardiovascular health in this age group is undefined. Objective The aim of this systematic review was to investigate the potential role of fruit and vegetable consumption in adolescent cardiovascular health. Data Sources Six electronic databases (BioMed Central, MEDLINE, Web of Science, CINAHL, Scopus, PsycINFO) were searched from database inception to December 2015. Study Selection The search strategy used the following sets of descriptors: adolescents; fruits and vegetables; cardiovascular risk indicators; cross-sectional and cohort studies. Data Extraction Potentially eligible articles were selected independently by 2 reviewers. Results Eleven articles meeting the inclusion criteria were included (10 cross-sectional, 1 cohort). The main reasons for study exclusion (n = 71) were misclassification of individuals as adolescents, an unspecified outcome that was incongruent with the definitions provided, and assessment of fruits and vegetables as part of a food pattern. Articles evaluated fruit and vegetable intake (separately, together, only vegetables, or with fruit juice) in diverse units, using food frequency questionnaires, 24-hour dietary recalls, and food records. One-third of the studies showed significant inverse associations of fruit and vegetable intake with systolic blood pressure, abdominal obesity, triglycerides, high-density lipoprotein cholesterol, and metabolic syndrome. Conclusions The associations between fruit and vegetable consumption and indicators of cardiovascular risk in adolescents are inconsistent, likely because of heterogeneity in the methods used to assess and classify consumption and to define cardiovascular risk in adolescents.

Serum oxidized low-density lipoprotein levels are related to cardiometabolic risk and decreased after a weight loss treatment in obese children and adolescents

The oxidation of low‐density lipoprotein (LDL) cholesterol particles is an early atherogeninic event. Obese pediatric populations have higher levels of oxidized LDL (oxLDL) than normal weight children. The aim of this study was to evaluate the effect of a weight loss program on the biochemical profile and oxLDL levels in Spanish obese children and adolescents.

Assessment of physical activity intensity and duration in the paediatric population: evidence to support an a priori hypothesis and sample size in the agreement between subjective and objective methods: Assessing physical activity

We aimed to provide evidence for an a priori hypothesis and sample size for subjectively assessing physical activity intensity and duration in paediatric population, adopting objective methods as the reference. We searched electronic databases, reference lists and author databases. Correlation coefficients were pooled as an indicator of agreement estimates. We found 183 agreement analyses (94.5% based on correlation coefficients) from 89 studies that met our inclusion criteria. We identified four physical activity parameters addressing intensity and two parameters addressing duration. The physical activity parameters focusing on intensity were measured only by questionnaires, and the best correlation was achieved by moderate‐to‐vigorous physical activity compared with a heart rate monitor. In addition, total physical activity duration had a stronger correlation with an accelerometer when measured by diaries or logs than when measured by questionnaires. In both cases, the correlation was moderate. Studies with sample sizes between 50 and 99 subjects showed measurements that were stable in both magnitude and interpretation. Our findings suggest that the agreement between subjective and objective methods for assessing physical activity intensity and duration is weak to moderate. Furthermore, sample sizes ranging from 50 to 99 subjects provide stable agreement estimates between methods.

Development of a Food Frequency Questionnaire for Assessing Dietary Intake in Children and Adolescents in South America: Development of a Food Frequency Questionnaire

This study aimed to describe the development of a food frequency questionnaire (FFQ) to assess dietary intake in South American children and adolescents.

Leptin and adiposity as mediators on the association between early puberty and several biomarkers in European adolescents: the HELENA Study

Abstract Background Adolescents having early puberty (EP) are more likely to have obesity and increased cardiometabolic and inflammatory markers and atherosclerosis risk. We aimed to assess the indirect and mediated effects of leptin and adiposity on the relation between EP and cardiometabolic and inflammatory markers in European adolescents. Methods A sample of 511 adolescents with EP (12.5–17.5 years) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study was studied. To assess whether leptin levels and adiposity mediate the relation between EP and several biomarkers, linear regression models for mediation analyses were performed. Results EP was positively associated with the atherogenic index (Ath-I) (β=0.174; 95%CI 0.029–0.265) and negatively associated with the C-reactive protein (CRP) (β=−0.284; 95%CI −0.542 to −0.028) in girls. These associations were fully mediated by leptin levels (9.5%) and adiposity (44%), respectively. Moreover, EP has indirect effects on the apolipoprotein A-1 (ApoA-1) levels through adiposity in girls (for body mass index [BMI], β=0.014; 95%CI 0.005–0.028, and for waist circumference [WC], β=0.011; 95%CI 0.003–0.024), and on ApoA-1 (β=0.012; 95%CI 0.004–0.025), apolipoprotein B (ApoB) (β=−0.004; 95%CI −0.011 to −0.0004) and CRP (β=−0.265; 95%CI −0.819 to −0.047) through abdominal fat in boys. Conclusions Leptin levels and adiposity seem to play an important indirect and mediation role in the association between EP and cardiometabolic and inflammatory markers in adolescents. Weight control should be recommended in order to control the impaired cardiometabolic and inflammatory status arising in early pubertal adolescents.