Inflammation markers are associated with Cardiovascular diseases risk in adolescents The Young Hearts Project 2000

Purose: The traditional approach for identifying subjects at risk from cardiovascular diseases (CVD) is to determine the extent of clustering of biological risk factors adjusted for lifestyle. Recently, markers of endothelial dysfunction and low grade inflammation, including high sensitivity C-reactive protein (hsCRP), soluble intercellular adhesion molecules (sICAM), and soluble vascular adhesion molecules (sVCAM), have been included in the detection for high risk individuals. However, the relationship of these novel biomarkers with CVD risk in adolescents remains unclear. The purpose of this study, therefore, was to establish the association of hsCRP, sICAM, and sVCAM with CVD risk in an adolescent population.
Methods: Data from the Young Hearts 2000 cross-sectional cohort study, carried out in 1999-2001, were used. From a total of 2,017 male and female participants, 95 obese subjects were identified and matched according to age, sex, and cigarette smoking, with 95 overweight and 95 normal-weight adolescents. Clustered CVD risk was computed using a sum of Z-scores of biological risk factors. The relationship was described using multiple linear regression analyses.
Results: hsCRP, sICAM, and sVCAM showed significant associations with CVD risk. hsCRP and sICAM had a positive relation with CVD risk, whereas sVCAM showed an inverse relationship. In this study, lifestyle factors showed no relation with CVD risk.
Conclusion: The results fit the hypothesized role of low grade inflammation and endothelial dysfunction in CVD risk in asymptomatic adolescents. The inverse relationship of VCAM, however, is hard to explain and indicates the complex mechanisms underlying CVD. Further research is needed to draw firm conclusions on the biomarkers used.

Is dieting behaviour decreasing in young adolescents?

Abstract Objective: To report trends in underweight, overweight and obesity in 12–15-year-old adolescents and examine changes in dieting behaviour, which have been less well documented. Design: Comparison of two independent representative cross-sectional surveys. Setting: Northern Ireland. Subjects: Weight and height were objectively measured in 1324 boys and 1160 girls in 1996 and 1274 boys and 1374 girls in 2007. Participants reported whether they were following any particular diet including a self-proposed or prescribed weight-reduction diet. Results: Overweight and obesity increased in girls from 15% to 23% and 2% to 6%, respectively. Increases were more modest in boys with overweight increasing from 13% to 18% and obesity from 3% to 6%. The proportion of underweight adolescents decreased from 9% to 6% in girls and 8% to 5% in boys. Evidence of social disparity was observed in girls from a manual socio-economic background, with overweight/obesity prevalence rates increasing from 21% to 36% compared with 15% to 26% in girls from a non-manual background. Despite these trends fewer adolescents, in particular girls, reported following weight-reduction diets (14% of overweight/obese girls in 2007 v. 21% in 1996; 8% of boys in 2007 v. 13% in 1996). Of these girls, the proportion from a manual background following weight-reduction diets decreased from 25% to 11%. Conclusions: Overweight and obesity are continuing to increase in adolescents despite government and media awareness strategies. There also appears to be reduced dieting behaviour, despite increasing body weight, particularly in girls from manual socio-economic backgrounds.

High-density lipoprotein subfractions display proatherogenic properties in overweight and obese children

BACKGROUND: In adults, obesity-driven inflammation can lead to increased cardiovascular disease (CVD). However, information regarding childhood obesity and its inflammatory sequelae is less well defined. Serum amyloid-A (SAA) is an inflammatory molecule that rapidly associates with high-density lipoproteins (HDLs) and renders them dysfunctional. Therefore, SAA may be a useful biomarker to identify increased CVD potential in overweight and obese children.

METHODS: Young Hearts 2000 is a cross-sectional cohort study in which 92 children who were obese were matched for age and sex with 92 overweight and 92 lean children. HDL2 and HDL3 (HDL2&3) were isolated from plasma by a three-step rapid-ultracentrifugation procedure. SAA was measured in serum and HDL2&3 by an enzyme-linked immunosorbent assay procedure, and the activities of cholesterol ester transfer protein (CETP) and lecithin cholesteryl acyltransferase (LCAT) were measured by fluorimetric assays.

RESULTS: Trends across the groups indicated that SAA increased in serum and HDL2&3 as BMI increased, as did HDL2-CETP and HDL2-LCAT activities.

CONCLUSION: These results have provided evidence that overweight and obese children are exposed to an inflammatory milieu that impacts the antiatherogenic properties of HDL and that could increase CVD risk. This supports the concept that it is important to target childhood obesity to help minimize future cardiovascular events.

Obesity markers and blood pressure in a sample of Portuguese children and adolescents.

Little information exists regarding the effect of several obesity markers on blood pressure (BP) levels in youth. Transverse study including 2494 boys and 2589 girls. Height, weight and waist were measured according to the international criteria and body fat (BF) by bioimpedance. BP was measured by an automated device. Hypertension was defined using sex-specific, age-specific and height-specific observation-points. Body mass index (BMI) and waist were positively related with systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate in both sexes, whereas the relationships with BF were less consistent. Stepwise linear regression analysis showed that BMI was positively related with SBP and DBP in both sexes, whereas BF was negatively related with SBP in both sexes and with heart rate in boys only; finally, waist was positively related with SBP in boys and heart rate in girls. Age and heart rate-adjusted values of SBP and DBP increased with BMI: for SBP, 117+/-1, 123+/-1 and 124+/-1 mmHg in normal, overweight and obese boys, respectively; corresponding values for girls were 111+/-1, 114+/-1 and 116+/-2 mmHg (mean+/-SE, P<0.001). Overweight and obese boys had an odds ratio for being hypertensive of 2.26 (95% confidence interval: 1.79-2.86) and 3.36 (2.32-4.87), respectively; corresponding values for girls were 1.58 (confidence interval 1.25-1.99) and 2.31 (1.53-3.50). BMI, not BF or waist, is consistently and independently related to BP levels in children; overweight and obesity considerably increase the risk of hypertension.

The Nutritional Status of Children and Adolescents with HIV/AIDS on Antiretroviral Therapy

The objective of this cross-sectional study was to assess the nutritional status of children and adolescents with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) receiving highly active antiretroviral therapy (HAART). One hundred and eighteen subjects aged 6-19 years attending an outpatient clinic in Sao Paulo city were involved in the study. The following anthropometric measurements were assessed: weight, height, waist circumference and triceps and subscapular skinfold thickness. One (0.9%) adolescent was diagnosed with abdominal obesity based on waist circumference measurement; three (2.5%) adolescents were obese based on subscapular skinfold thickness. According to the body mass index, the population studied was mainly eutrophic. The prevalence of fat redistribution, a characteristic of patients with HIV/AIDS under HAART, was low. We advise the development of further studies to assess the nutritional status of children and adolescents with HIV/AIDS using anthropometric measurements as well as computed tomography to detect fat redistribution.

Resting Heart Rate is Associated with Blood Pressure in Male Children and Adolescents

Objectives To analyze the association between resting heart rate and blood pressure in male children and adolescents and to identify if this association is mediated by important confounders.Study design Cross-sectional study carried out with 356 male children and adolescents from 8 to 18 years old. Resting heart rate was measured by a portable heart rate monitor according to recommendations and stratified into quartiles. Blood pressure was measured with an electronic device previously validated for pediatric populations. Body fatness was estimated by a dual-energy x-ray absorptiometry.Results Obese subjects had values of resting heart rate 7.8% higher than nonobese (P = .001). Hypertensive children and adolescents also had elevated values of resting heart rate (P = .001). When the sample was stratified in nonobese and obese, the higher quartile of resting heart rate was associated with hypertension in both groups of children and adolescents.Conclusions This study confirms the existence of a relationship between elevated resting heart rate and increased blood pressure in a pediatric population, independent of adiposity, ethnicity and age. (J Pediatr 2011; 158:634-7).

Modifiable risk factors for overweight and obesity in children and adolescents from São Paulo, Brazil

Background: Brazil is currently experiencing a nutrition transition: the displacement of traditional diets with foods high in saturated fat, sodium, and cholesterol and an increase in sedentary lifestyles. Despite these trends, our understanding of child obesity in Brazil is limited. Thus, the aims of this study were (1) to investigate the current prevalence of overweight and obesity in a large sample of children and adolescents living in São Paulo, Brazil, and (2) to identify the lifestyle behaviors associated with an increased risk of obesity in young Brazilians.Methods: A total of 3,397 children and adolescents (1,596 male) aged 7-18 years were randomly selected from 22 schools in São Paulo, Brazil. Participants were classified as normal weight, overweight, or obese based on international age-and sex-specific body mass index thresholds. Selected sociodemographic, physical activity, and nutrition behaviors were assessed via questionnaire.Results: Overall, 19.4% of boys and 16.1% of girls were overweight while 8.9% and 4.3% were obese. Two-way analysis of variance revealed that the prevalence of overweight and obesity was significantly higher in boys and in younger children when compared to girls and older children, respectively (P < 0.05 for both). Logistic regression analysis revealed that overweight was associated with more computer usage, parental encouragement to be active, and light soft drink consumption after controlling for differences in sex, age, and parental education (P < 0.05 for all). Conversely, overweight was associated with less active transport to school, eating before sleep, and consumption of breakfast, full-sugar soft drinks, fried food and confectionery (P < 0.05 for all).Conclusions: Our results show that obesity in São Paulo children and adolescents has reached a level equivalent to that seen in many developed countries. We have also identified three key modifiable factors related to obesity that may be appropriate targets for future intervention in Brazilian youth: transport mode to school, computer usage, and breakfast consumption.

Construct validity of a figure rating scale for Brazilian adolescents

Background: Figure rating scales were developed as a tool to determine body dissatisfaction in women, men, and children. However, it lacks in the literature the validation of the scale for body silhouettes previously adapted. We aimed to obtain evidence for construct validity of a figure rating scale for Brazilian adolescents.Methods: The study was carried out with adolescent students attending three public schools in an urban region of the municipality of Florianopolis in the State of Santa Catarina (SC). The sample comprised 232 10-19-year-old students, 106 of whom are boys and 126 girls, from the 5th series (i.e. year) of Primary School to the 3rd year of Secondary School. Data-gathering involved the application of an instrument containing 8 body figure drawings representing a range of children's and adolescents' body shapes, ranging from very slim (contour 1) to obese (contour 8). Weights and heights were also collected, and body mass index (BMI) was calculated later. BMI was analyzed as a continuous variable, using z-scores, and as a dichotomous categorical variable, representing a diagnosis of nutritional status (normal and overweight including obesity).Results: Results showed that both males and females with larger BMI z-scores chose larger body contours. Girls with higher BMI z-scores also show higher values of body image dissatisfaction.Conclusion: We provided the first evidence of validity for a figure rating scale for Brazilian adolescents.

Intra-abdominal fat is related to metabolic syndrome and non-alcoholic fat liver disease in obese youth

Background: Previous studies have shown an association between adiposity, especially intra-abdominal adipose tissue, and hemodynamic/metabolic comorbidities in adults, however it is not clear in pediatric population. The aim of the study was to analyze the relationship between non-alcoholic fatty liver disease (NAFLD) and components of metabolic syndrome (MS) with values of intra-abdominal (IAAT) and subcutaneous (SCAT) adipose tissue in obese children and adolescents.Methods: Cross-sectional study. Subjects: 182 obese sedentary children and adolescents (aged 6 to 16 y), identified by the body mass index (BMI). Measurements: Body composition and trunk fat by dual-energy X-ray absorptiometry- DXA; lipid profile, blood pressure and pubertal stage were also assessed. NAFLD was classified as absent (0), mild (1), moderate (2) and severe (3), and intra-abdominal and subcutaneous abdominal fat thickness were identified by ultrasound. The MS was identified according to the cut offs proposed by World Health Organization adapted for children and adolescents. The chi-square test was used to compare categorical variables, and the binary logistic regression indicated the magnitude of the associations adjusted by potential cofounders (sex, age, maturation, NAFLD and HOMA-IR).Results: Higher quartile of SCAT was associated with elevated blood pressure (p = 0.015), but not associated with NAFLD (p = 0.665). Higher IAAT was positively associated with increased dyslipidemia (p = 0.001), MS (p = 0.013) and NAFLD (p = 0.005). Intermediate (p = 0.007) and highest (p = 0.001) quartile of IAAT were also associated with dyslipidemia, independently of age, sex, maturation, NAFLD and HOMA-IR (homeostatic model assessment-insulin resistance).Conclusion: Obese children and adolescents, with higher IAAT are more prone to develop MS and NAFLD than those with higher values of SCAT, independent of possible confounding variables. © 2013 Silveira et al.; licensee BioMed Central Ltd.

Prevalence of cardiovascular risk factors among Latin American adolescents: a multilevel analysis

High blood pressure (HBP) and obesity is a well-established major risk factor for stroke and coronary heart disease. However, the literatures are scarce about these informations in adolescents from low-and-middle income countries. This school-based survey was carried out among students from Maringá (Brazil) and Buenos Aires (Argentina) selected random sampling. We studied 991 Brazilian adolescents (54.5% girls) in the age range of 14-18 years. In Argentina, we studied 933 adolescents (45.9% female) in the age range of 11-17 years. The outcomes of this study are general obesity, abdominal obesity and HBP. The associated factors analysed were gender, age and health behaviours. The prevalence of obesity was 5.8% in Brazil and 2.8% in Argentina, the prevalence of abdominal obesity was 32.7% in Brazil and 11.1% in Argentina, the prevalence of HBP was 14.9% in Brazil and 13.5% in Argentina. The multilevel analysis showed that older adolescents (>14 years old) have a little likelihood of being overweight, whereas male adolescents are more likely to be obese and have HBP. The abdominal obesity in both indicators were not associated with the independent variables. The prevalence of cardiovascular risk factors is high in Latin American adolescents independent of each country, and was associated with male gender.Journal of Human Hypertension advance online publication, 15 August 2013; doi:10.1038/jhh.2013.74.

Higher screen time is associated with overweight, poor dietary habits and physical inactivity in Brazilian adolescents, mainly among girls

To analyse the associations between high screen time and overweight, poor dietary habits and physical activity in adolescents according to sex. The study comprised 515 boys and 716 girls aged 14-17 years from Londrina, Brazil. Nutritional status (normal weight or overweight/obese) was assessed by calculating the body mass index. Eating habits and time spent in physical activity were reported using a questionnaire. The measurement of screen time considered the time spent watching television, using a computer and playing video games during a normal week. Associations between high screen time and dependent variables (nutritional status, eating habits and physical activity levels) were assessed by binary logistic regression, adjusted for sociodemographic and lifestyle variables. Most adolescents (93.8% of boys and 87.2% of girls) spent more than 2 hours per day in screen-time activities. After adjustments, an increasing trend in the prevalence of overweight and physical inactivity with increasing time spent on screen activities was observed for both sexes. Screen times of >4 hours/day compared with <2 hours/day were associated with physical inactivity, low consumption of vegetables and high consumption of sweets only in girls and the consumption of soft drinks in both sexes. The frequency of overweight and physical inactivity increased with increasing screen time in a trending manner and independently of the main confounders. The relationship between high screen time and poor eating habits was particularly relevant for adolescent girls.

Matrix metalloproteinase-9 genetic variations affect MMP-9 levels in obese children

Objective: Matrix metalloproteinase-9 (MMP-9) is involved in the atherosclerotic process and functional polymorphisms in the MMP-9 gene affect MMP-9 expression/activity, and are associated with cardiovascular diseases. However, no study has tested the hypothesis that functional MMP-9 polymorphisms could affect MMP-9 levels in obese children. We investigated whether three MMP-9 gene polymorphisms (C-1562T (rs3918242), 90(CA)((14-24)) (rs2234681) and Q279R (rs17576)), or haplotypes, affect MMP-9 levels in obese children. Methods: We studied 175 healthy control children and 127 obese children. Plasma MMP-9, tissue inhibitor of MMPs (TIMP)-1 and adiponectin concentrations were measured using enzyme-linked immunosorbent assay. Results: We found similar MMP-9 genotypes, allelic and haplotypes distributions in the two study groups (P > 0.05). However, we found lower plasma MMP-9 concentrations in obese subjects carrying the CC or the QQ genotypes for the C-1562T and the Q279R polymorphisms, respectively, in obese children compared with children with the other genotypes, or with non-obese children with the same genotypes (all P < 0.05). Moreover, we found lower MMP-9 levels and lower MMP-9/TIMP-1 ratios (which reflect net MMP-9 activity) in obese children carrying the H2 haplotype (which combines the C, H and Q alleles for the three polymorphisms, respectively) when compared with obese children carrying the other haplotypes, or with non-obese children carrying the same haplotype (P < 0.05). Conclusions: Our findings show that MMP-9 genotypes and haplotypes affect MMP-9 levels in obese children and adolescents, and suggest that genetic factors may modify relevant pathogenetic mechanisms involved in the development of cardiovascular complications associated with obesity in childhood. International Journal of Obesity (2012) 36, 69-75; doi:10.1038/ijo.2011.169; published online 16 August 2011

Influence of obesity and cardiometabolic makers on lipoprotein-associated phospholipase A2 (Lp-PLA2) activity in adolescents: the healthy young cross-sectional study

Abstract Background Lipoprotein-associated phospholipase A2 activity (Lp-PLA2) is a good marker of cardiovascular risk in adults. It is strongly associated with stroke and many others cardiovascular events. Despite this, the impact of obesity on this enzyme activity and its relation to biomarkers of cardiovascular disease in adolescents is not very well investigated. The purpose of this article is to evaluate the influence of obesity and cardiometabolic markers on Lp-PLA2 activity in adolescents. Results This cross-sectional study included 242 adolescents (10–19 years) of both gender. These subjects were classified in Healthy Weight (n = 77), Overweight (n = 82) and Obese (n = 83) groups. Lipid profile, glucose, insulin, HDL size, LDL(−) and anti-LDL(−) antibodies were analyzed. The Lp-PLA2 activity was determined by a colorimetric commercial kit. Body mass index (BMI), waist circumference and body composition were monitored. Food intake was evaluated using three 24-hour diet recalls. The Lp-PLA2 activity changed in function to high BMI, waist circumference and fat mass percentage. It was also positively associated with HOMA-IR, glucose, insulin and almost all variables of lipid profile. Furthermore, it was negatively related to Apo AI (β = −0.137; P = 0.038) and strongly positively associated with Apo B (β = 0.293; P < 0.001) and with Apo B/Apo AI ratio (β = 0.343; P < 0.001). The better predictor model for enzyme activity, on multivariate analysis, included Apo B/Apo AI (β = 0.327; P < 0.001), HDL size (β = −0.326; P < 0.001), WC (β = 0.171; P = 0.006) and glucose (β = 0.119; P = 0.038). Logistic regression analysis demonstrated that changes in Apo B/Apo AI ratio were associated with a 73.5 times higher risk to elevated Lp-PLA2 activity. Conclusions Lp-PLA2 changes in function of obesity, and that it shows important associations with markers of cardiovascular risk, in particular with waist circumference, glucose, HDL size and Apo B/Apo AI ratio. These results suggest that Lp-PLA2 activity can be a cardiovascular biomarker in adolescence.

Effectiveness of dietary intervention in children and adolescents with elevated blood pressure

Hypertension is a known risk factor for cardiovascular disease in adults. Essential hypertension in children and adolescents is increasing in prevalence in the United States, and hypertension in children may track into adulthood. This increasing prevalence is attributed to the trends of increasing overweight and obese children and adolescents. Family history and being of African-American/black descent may predispose youth to elevated blood pressure. Interventions targeted to reduce and treat hypertension in youth include non-pharmaceutical interventions such as weight reduction, increased physical activity, and dietary changes and pharmaceutical treatment when indicated. The effectiveness of non-pharmaceutical interventions is well documented in adults, but there are limited studies with regards to children and adolescents, specifically in the arena of dietary interventions. Lifestyle modifications such as dietary interventions are the mainstay of recommended treatment for those children and adolescents with prehypertension or stage 1 hypertension. Given the association of being overweight and hypertension, efficacy of dietary interventions are of interest because of reduced cost, easy implementation and potential for multiple beneficial outcomes such as reduced weight and reduction of other metabolic or cardiovascular derangements. Barriers to dietary interventions often include socioeconomic status, ethnicity, personal, and external factors. The goal of this systematic review of the literature is to identify interventions targeted to children and adolescents that focus on recommended dietary changes related to blood pressure. Dietary interventions found for this review mostly focused on a particular nutrient or food group with the one notable exception that focused on the DASH pattern of eating. The effects of the interventions on blood pressure varied, but overall dietary modifications can be achieved in youth and can serve a role in producing positive outcomes on blood pressure. Increasing potassium and following a DASH diet seemed to provide the most clinically significant results. Further studies are still needed to evaluate long-term effectiveness and to contribute more supporting evidence for particular modifications in these age cohorts.^

Is obesity associated with increased symptoms of psychiatric morbidity among Indian adolescents?

The relationship between obesity and mental health disorders has not been explored among adolescents in India. Although evidence from western countries has failed to demonstrate conclusive associations, a tremendous increase in the prevalence of obesity and overweight among urban adolescents in India, along with an absolute lack of studies into mental health of Indian adolescents, necessitate the need for research in this population. This present study used data collected from 861 urban 6th and 8th graders from Delhi, India and tested for the associations of weight status with psychiatric symptomatology and other weight related behaviors. The Strengths and Difficulties questionnaire (SDQ) was used to collect data on psychiatric symptoms. Falling into the overweight or obese category was hypothesized to be associated with borderline or abnormal scores on the SDQ scales. Results indicated a high prevalence for overweight/obesity among the population (>30%). No significant associations were demonstrated between weight status and borderline/abnormal SDQ scores on all the scales. However, significant associations were found between sedentary behaviors (screen time >2 hrs daily), positive and negative weight-control behaviors and borderline/abnormal SDQ scores on various scales. In light of these new findings, a further exploration of the relationship in this population is indicated.^