Metabolic syndrome in overweight and obese adolescents: a comparison of two different diagnostic criteria

Breastfeeding Duration and Cardiometabolic Health during Adolescence: A Longitudinal Analysis

OBJECTIVE

To investigate the longitudinal association between breastfeeding duration and cardiometabolic health, using repeated measures study design among children and adolescents.

STUDY DESIGN

This study included 634 offsprings aged 10 to 21 years (52% female) from the Early Life Exposure in Mexico to Environmental Toxicants birth cohort followed up to four time points during adolescence. Breastfeeding duration was prospectively quantified using questionnaires during early childhood. Cardiometabolic risk factors, body composition, and weight-related biomarkers were assessed as outcomes during adolescent follow-up visits. Sex-stratified linear mixed-effects models were used to model the association between quartiles of breastfeeding duration and outcomes, adjusting for age and additional covariates.

RESULTS

Median breastfeeding duration was 7 months (minimum = 0, maximum = 36). Boys in the second quartile (median breastfeeding = 5 months) had lower total fat mass % (β (SE) -3.2 (1.5) P = .037), and higher lean mass % (3.1 (1.6) P = .049) and skeletal muscle mass % (1.8 (0.8) P = .031) compared with the reference group (median breastfeeding = 2 months). A positive linear trend between breastfeeding duration and trunk lean mass % (0.1 (0.04) P = .035) was found among girls. No association was found with other cardiometabolic indicators.

CONCLUSION

Despite sex-specific associations of breastfeeding duration with body composition, there was a lack of substantial evidence for the protective effects of breastfeeding against impaired cardiometabolic health during adolescence among Mexican youth. Further longitudinal studies with a robust assessment of breastfeeding are recommended.

Polymorphisms of Fat Mass and Obesity-Associated Gene in the Pathogenesis of Child and Adolescent Metabolic Syndrome

Childhood metabolic syndrome (MetS) is prevalent around the world and is associated with a high likelihood of suffering from severe diseases such as cardiovascular disease later in adulthood. MetS is associated with genetic susceptibility that involves gene polymorphisms. The fat mass and obesity-associated gene (FTO) encodes an RNA N6-methyladenosine demethylase that regulates RNA stability and molecular functions. Human FTO contains genetic variants that significantly contribute to the early onset of MetS in children and adolescents. Emerging evidence has also uncovered that FTO polymorphisms in intron 1, such as rs9939609 and rs9930506 polymorphisms, are significantly associated with the development of MetS in children and adolescents. Mechanistic studies reported that FTO polymorphisms lead to aberrant expressions of FTO and the adjacent genes that promote adipogenesis and appetite and reduce steatolysis, satiety, and energy expenditure in the carriers. The present review highlights the recent observations on the key FTO polymorphisms that are associated with child and adolescent MetS with an exploration of the molecular mechanisms underlying the development of increased waist circumference, hypertension, and hyperlipidemia in child and adolescent MetS.

DNA Methylation Is a Potential Biomarker for Cardiometabolic Health in Mexican Children and Adolescents

DNA methylation (DNAm) is a plausible mechanism underlying cardiometabolic abnormalities, but evidence is limited among youth. This analysis included 410 offspring of the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) birth cohort followed up to two time points in late childhood/adolescence. At Time 1, DNAm was quantified in blood leukocytes at long interspersed nuclear elements (LINE-1), H19, and 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD-2), and at Time 2 in peroxisome proliferator-activated receptor alpha (PPAR-α). At each time point, cardiometabolic risk factors were assessed including lipid profiles, glucose, blood pressure, and anthropometry. Linear mixed effects models were used for LINE-1, H19, and 11β-HSD-2 to account for the repeated-measure outcomes. Linear regression models were conducted for the cross-sectional association between PPAR-α with the outcomes. DNAm at LINE-1 was associated with log glucose at site 1 [β = -0.029, p = 0.0006] and with log high-density lipoprotein cholesterol at site 3 [β = 0.063, p = 0.0072]. 11β-HSD-2 DNAm at site 4 was associated with log glucose (β = -0.018, p = 0.0018). DNAm at LINE-1 and 11β-HSD-2 was associated with few cardiometabolic risk factors among youth in a locus-specific manner. These findings underscore the potential for epigenetic biomarkers to increase our understanding of cardiometabolic risk earlier in life.

Diet Quality Scores and Cardiometabolic Risk Factors in Mexican Children and Adolescents: A Longitudinal Analysis

There is limited evidence for the effects of diet on cardiometabolic profiles during the pubertal transition. We collected repeated measures of diet quality and cardiometabolic risk factors among Mexican youth. This analysis included 574 offspring of the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) birth cohort followed up to three time points. Dietary Approaches to Stop Hypertension (DASH), alternate Mediterranean Diet (aMedDiet), and Children’s Dietary Inflammatory Index (C-DIITM) scores were computed from food frequency questionnaires. Higher DASH and aMedDiet scores reflect a higher diet quality, and lower C-DII scores reflect an anti-inflammatory diet. Cardiometabolic risk factors were lipid profile, glucose homeostasis, blood pressure, and waist circumference. Linear mixed models were used between quartiles of each diet score and outcomes. Compared to the first quartile, the fourth DASH quartile was inversely associated with log serum insulin (μIU/mL) [β = −0.19, p = 0.0034] and log-Homeostatic Model Assessment of Insulin Resistance [β = −0.25, p = 0.0008]. Additionally, log serum triglycerides (mg/dL) was linearly associated with aMedDiet score [β = −0.03, p = 0.0022]. Boys in the highest aMedDiet quartile had higher serum high-density lipoprotein cholesterol (mg/dL) [β = 4.13, p = 0.0034] compared to the reference quartile. Higher diet quality was associated with a better cardiometabolic profile among Mexican youth.

Concordance among diagnostic criteria for metabolic syndrome is inconsistent in Spanish adolescents

BACKGROUND

The metabolic syndrome (MetS), although more frequent in adults, is a growing health problem in adolescent population. There are different criteria for the diagnosis, however without a consensus of which is the best to be used in this population. The heterogeneity of the different diagnostic criteria makes it necessary to carry out more studies that analyse the degree of agreement among these criteria. The present study was aimed to evaluate the agreement between different criteria for diagnosis of MetS in adolescents.

MATERIALS AND METHODS

A cross-sectional study was performed on 981 adolescents (13.2 ± 1.2 years) randomly recruited from 18 schools in south-east Spain. MetS was diagnosed by eight different criteria.

RESULTS

The criteria proposed by the IDF showed the highest mean values for WC and systolic blood pressure in boys and girls with MetS, and the lowest for glucose and triglycerides in boys. Depending on the diagnostic criteria used, the prevalence of MetS cases in boys ranged from 5.5% to 14.9%, while in girls varied from 3.4% to 32.6%. Both in boys and girls, the criteria proposed by the IDF was the less concordant with the other suggested criteria, while those proposed by Duncan et al, Rodriguez-Moran et al and Cruz and Goran, were very concordant among each other. However, in girls, concordance values were not as high as those found for boys.

CONCLUSION

The variability observed in the agreement among the existing criteria suggests the need to validate uniform criteria for the diagnosis of MetS in adolescents.

Prevalence of Metabolic Syndrome and Impaired Glucose Metabolism among 10- to 17-Year-Old Overweight and Obese Lithuanian Children and Adolescents

BACKGROUND

Overweight (Ow) and obesity among adults and children increases the risk of metabolic consequences. Metabolic syndrome (MS) and impaired glucose metabolism are well-known risk factors for cardiovascular diseases and type 2 diabetes. The aim of this study was to evaluate the prevalence of MS and impaired glucose metabolism among Ow and obese (Ob) children and adolescents (aged 10-17 years) in Lithuania, and to evaluate the associations between insulin resistance (IR) indices and anthropometric parameters as well as metabolic disturbances.

METHODS

The study population consisted of 344 OwOb children and adolescents of all pubertal stages. Oral glucose tolerance tests (OGTTs), IR and β cell function indices, lipid profile, and anthropometric parameters of all subjects were analyzed. MS was defined according to the International Diabetes Federation consensus guidelines.

RESULTS

MS was found in 21.3% of the OwOb children and adolescents, and 12.1% had impaired glucose metabolism (6.9% with impaired fasting glucose, 4.5% with impaired glucose tolerance, and 0.6% with type 2 diabetes). IR was directly related to body mass index and waist circumference, waist-to-height and waist-to-hip ratios, and sum of skin-fold thicknesses. Children with MS were more insulin-resistant, had higher odds ratio for prediabetes and had a more disturbed lipid profile than subjects without MS. Moreover, total cholesterol and low-density lipoprotein cholesterol levels were significantly lower in the more mature OwOb adolescents.

CONCLUSION

MS and lipid profile disturbances are common in OwOb children and adolescents. MS is directly associated with IR. Therefore, OwOb children and adolescents should be carefully followed up for metabolic abnormalities during late childhood as these can persist into adulthood.

Metabolic syndrome among children and adolescents in low and middle income countries: a systematic review and meta-analysis

BACKGROUND

Metabolic syndrome (MetS) is a clustering of cardiovascular risk factors, which is rising in the low and middle income countries (LMICs). There are various studies with inconsistent findings that are inconclusive for policy makers and program planners. Thus, this systematic review and meta-analysis aimed at estimating the pooled prevalence of MetS and its components in LMICs.

METHODS

Electronic searches were conducted in international databases including PubMed, Web of Science, EMBASE (Elsevier), Scopus, CINAHL (EBSCOhost), Science direct (Elsevier), Food Science and Technology Abstracts (FSTA), Global Health and Medline, and other sources (World Cat, Google Scholar, and Google). The pooled estimates were computed in the random effect model. The pooled prevalence was computed using the three diagnostic methods (IDF, ATP III and de Ferranti). Publication bias was verified using funnel plot and Egger's regression test. Subgroup and sensitivity analysis were performed to identify the possible sources of heterogeneity among the included studies.

RESULT

In this study, 142,142 children and adolescents from 76 eligible articles were included to compute the pooled prevalence of MetS and its components in LMCIs. MeTs among overweight and obese population was computed from 20 articles with the pooled prevalence of 24.09%, 36.5%, and 56.32% in IDF, ATP III and de Ferranti criteria, respectively. Similarly, a total of 56 articles were eligible to compute the pooled prevalence of MetS in the general population of children and adolescents. Hence, Mets was found in 3.98% (IDF), 6.71% (ATP III) and 8.91% (de Ferranti) of study subjects. Regarding the components of MetS, abdominal obesity was the major component in overweight and obese population and low HDL-C was the most common component in the general population. This study also revealed that males were highly affected by MetS than females.

CONCLUSION

This study illustrates that MetS among children and adolescents is an emerging public health challenge in LMICs, where the prevalence of obesity is on the move. Preventive strategies such as community and school based intervention need to be designed. Promoting physical activities and healthy eating behaviors could avert this problem.

Anthropometric measurements as a potential non-invasive alternative for the diagnosis of metabolic syndrome in adolescents

OBJECTIVE

To identify which anthropometric measurement would be the best predictor of metabolic syndrome (MetS) in Brazilian adolescents.

SUBJECTS AND METHODS

Cross-sectional study conducted on 222 adolescents (15-17 years) from a city in southern Brazil. Anthropometric, physical activity, blood pressure and biochemical parameters were investigated. MetS criteria were transformed into a continuous variable (MetS score). Linear regression analyses were performed to assess the associations of BMI, hip circumference, neck circumference (NC), triceps skinfold, subscapular skinfold and body fat percentage with MetS score. ROC curves were constructed to determine the cutoff for each anthropometric measurement.

RESULTS

The prevalence of MetS was 7.2%. Each anthropometric measurement was significantly (p < 0.001) associated with MetS score. After adjusting for potential confounding variables (age, sex, physical activity, and maternal education), the standardized coefficients of NC and body fat percentage appeared to have the strongest association (beta = 0.69 standard deviation) with MetS score. The regression of BMI provided the best model fit (adjusted R2 = 0.31). BMI predicted MetS with high sensitivity (100.0%) and specificity (86.4%).

CONCLUSIONS

Our results suggest that BMI and NC are effective screening tools for MetS in adolescents. The early diagnosis of MetS combined with targeted lifestyle interventions in adolescence may help reduce the burden of cardiovascular diseases and diabetes in adulthood.

Using height-corrected definition of metabolic syndrome in children and adolescents

Metabolic syndrome (MS) is common among children and adolescents. Age- and gender-specific references or age-, gender- and height-specific references were used in pediatric MS definitions. More recently, an increasing number of studies documented that the ratio of waist circumference (WC) to height (WHtR) and blood pressure to height (BPHR) were easy anthropometric indexes for detection of obesity and hypertension in children and adolescents. For these reasons, height-corrected MS definition was proposed. WHtR and BPHR were used as alternatives to WC and BP in the definition of MS. In the present review, we discuss the possibility of the height-corrected MS definition for identifying MS in children.

New Insights about How to Make an Intervention in Children and Adolescents with Metabolic Syndrome: Diet, Exercise vs. Changes in Body Composition. A Systematic Review of RCT

OBJECTIVE

To record which interventions produce the greatest variations in body composition in patients ≤19 years old with metabolic syndrome (MS).

METHOD

search dates between 2005 and 2017 in peer reviewed journals, following the PRISMA method (Preferred Reporting Items for Systematic reviews and Meta-Analyses). The selection criteria were: diagnostic for MS or at least a criterion for diagnosis; randomized clinical trials, ≤19 years of age; intervention programs that use diet and/or exercise as a tool (interventions showing an interest in body composition).

RESULTS

1781 clinical trials were identified under these criteria but only 0.51% were included. The most frequent characteristics of the selected clinical trials were that they used multidisciplinary interventions and were carried out in America. The most utilized parameters were BMI (body mass index) in kg/m² and BW (body weight) in kg.

CONCLUSIONS

Most of the clinical trials included had been diagnosed through at least 2 diagnostic criteria for MS. Multidisciplinary interventions obtained greater changes in body composition in patients with MS. This change was especially prevalent in the combinations of dietary interventions and physical exercise. It is proposed to follow the guidelines proposed for patients who are overweight, obese, or have diabetes type 2, and extrapolate these strategies as recommendations for future clinical trials designed for patients with MS.

C-reactive protein in Brazilian adolescents: distribution and association with metabolic syndrome in ERICA survey

BACKGROUND/OBJECTIVES

C-reactive protein (CRP) is a marker of inflammation that has been shown to be predictive of cardiovascular diseases in adults. To evaluate the distribution of CRP as well as its association with metabolic syndrome and its components.

SUBJECTS/METHODS

This is a cross-sectional study on adolescents aged 12-17, participants in the Study of Cardiovascular Risk in Adolescents (ERICA). Anthropometric, biochemical and blood pressure data were collected from 6316 adolescents, selected from a random sample of students in the cities of Brasilia, Fortaleza, João Pessoa, Manaus, Porto Alegre and Rio de Janeiro. Metabolic syndrome was defined by the criteria proposed by International Diabetes Federation for adolescent. Poisson regression model with robust variance, taking into consideration the study's complex sampling design, was used to determine multivariate-adjusted prevalence rate ratios expressing the relationship of metabolic syndrome with CRP.

RESULTS

In adolescents with metabolic syndrome, CRP concentrations were five times higher (1.01 mg/l; interquartile range (IQR): 0.54-3.47) compared with those without metabolic syndrome (0.19 mg/l; IQR: 0.10-0.78). In multivariate Poisson regression analysis adjusted by sex, age and skin color, the prevalence of elevated CRP (>3.0 mg/l) was almost three times higher in adolescents with metabolic syndrome than in those without this condition (prevalence ratio (PR): 2.9; 95%CI: 2.0-4.3; P<0.001). Of the metabolic syndrome components, elevated waist circumference, low high-density lipoprotein-cholesterol and high triglycerides were significantly related to CRP in a graded (dose-response) manner.

CONCLUSIONS

The association of CRP with metabolic syndrome and its components suggests that inflammation may be useful in assessing cardiovascular risk in adolescents.

How Accurate Is a Single Cutpoint to Identify High Blood Pressure in Adolescents?

In 2007 the International Diabetes Federation (IDF) proposed single blood pressure (BP) cutpoints (systolic: ≥130 mm Hg and diastolic: ≥85 mm Hg) for the diagnosis of high blood pressure (HBP) in adolescents. Before this proposal, HBP had been defined as BP at or above the 95th percentile for age, sex, and height percentile (reference standard). In this study, we evaluated the risk for misclassification when using the IDF single-cutpoints criteria. We first applied the IDF criteria to a reconstructed population with the same age, sex, and height distribution as the population used to develop the reference standard. The proposed single cutpoints corresponded to percentiles from the 81.6th to 99.9th for systolic BP and from the 92.9th to 98.9th for diastolic BP in the reconstructed population. Using IDF criteria, there were high false-negative fractions for both systolic and diastolic BP (from 54% to 93%) in 10- to 12-year-olds and a false-positive fraction up to 35% in older subjects. We then applied the IDF criteria to 1,162 overweight/obese adolescents recruited during 1998-2000 from pediatric clinical centers in Milano, Varese, and Modena in Italy and in Zaragoza, Spain. Overall false-negative and false-positive fractions were 22% and 2%, respectively; negative predictive values were especially low for 10- to 12-year-old subjects. The use of IDF's single cutpoints carries a high risk of misclassification, mostly due to false negatives in younger subjects. The effort to simplify diagnosis could be overcome by the risk of undiagnosed HBP.

ERICA: prevalence of metabolic syndrome in Brazilian adolescents

OBJECTIVE

To determine the prevalence of metabolic syndrome and its components in Brazilian adolescents.

METHODS

We evaluated 37,504 adolescents who were participants in the Study of Cardiovascular Risks in Adolescents (ERICA), a cross-sectional, school-based, national study. The adolescents, aged from 12 to 17 years, lived in cities with populations greater than 100,000 inhabitants. The sample was stratified and clustered into schools and classes. The criteria set out by the International Diabetes Federation were used to define metabolic syndrome. Prevalences of metabolic syndrome were estimated according to sex, age group, school type and nutritional status.

RESULTS

Of the 37,504 adolescents who were evaluated: 50.2% were female; 54.3% were aged from 15 to 17 years, and 73.3% were from public schools. The prevalence of metabolic syndrome was 2.6% (95%CI 2.3-2.9), slightly higher in males and in those aged from 15 to 17 years in most macro-regions. The prevalence was the highest in residents from the South macro-region, in the younger female adolescents and in the older male adolescents. The prevalence was higher in public schools (2.8% [95%CI 2.4-3.2]), when compared with private schools (1.9% [95%CI 1.4-2.4]) and higher in obese adolescents when compared with nonobese ones. The most common combinations of components, referring to 3/4 of combinations, were: enlarged waist circumference (WC), low HDL-cholesterol (HDL-c) and high blood pressure; followed by enlarged WC, low HDL-c and high triglycerides; and enlarged WC, low HDL-c, high triglycerides and blood pressure. Low HDL was the second most frequent component, but the highest prevalence of metabolic syndrome (26.8%) was observed in the presence of high triglycerides.

CONCLUSIONS

ERICA is the first Brazilian nation-wide study to present the prevalence of metabolic syndrome and describe the role of its components. Despite the prevalence of Metabolic Syndrome being low, the high prevalences of some components and participation of others in the syndrome composition shows the importance of early diagnosis of this changes, even if not grouped within the metabolic syndrome.

Pharmacogenetics of Risperidone and Cardiovascular Risk in Children and Adolescents

Objective. To identify the frequency of obesity and metabolic complications in child and adolescent users of risperidone. Potential associations with clinical parameters and SNPs of the HTR2C, DRD2, LEP, LEPR, MC4R, and CYP2D6 genes were analyzed. Methods. Samples from 120 risperidone users (8-20 years old) were collected and SNPs were analyzed, alongside assessment of chronological and bone ages, prescribed and weight-adjusted doses, use of other psychotropic drugs, waist circumference, BMI z-scores, blood pressure, HOMA-IR index, fasting levels of serum glucose, insulin, cholesterol, triglycerides, transaminases, and leptin. Results. Thirty-two (26.7%) patients were overweight and 5 (4.2%) obese. Hypertension was recorded in 8 patients (6.7%), metabolic syndrome in 6 (5%), and increased waist circumference in 20 (16.7%). The HOMA-IR was high for 22 patients (18.3%), while total cholesterol and triglycerides were high in 20 (16.7%) and 41 (34.2%) patients, respectively. SNP associations were found for LEP, HTR2C, and CYP2D6 with BMI; CYP2D6 with blood pressure, ALT, and HOMA-IR; HTR2C and LEPR with leptin levels; MC4R and DRD2 with HOMA-IR; HTR2C with WC; and LEP with ALT. Conclusions. Although not higher than in the general pediatric population, a high frequency of patients was overweight/obese, with abnormalities in metabolic parameters and some pharmacogenetic associations.

Association between serum free fatty acid levels and nonalcoholic fatty liver disease: a cross-sectional study

High serum free fatty acid (FFA) levels are associated with metabolic syndrome (MS). This study aimed to assess the association of fasting serum FFAs with nonalcoholic fatty liver disease (NAFLD) in a Chinese population. A total of 840 subjects fulfilled the diagnostic criteria of NAFLD and 331 healthy control participants were enrolled in this cross-sectional study. Fasting serum FFA levels and other clinical and laboratory parameters were measured. NAFLD patients had significantly higher serum FFA levels than controls (P < 0.001). Serum FFA levels were significantly and positively correlated with parameters of MS, inflammation indexes, and markers of hepatocellular damage. Elevated serum FFA levels were found in NAFLD subjects with individual components of MS (obesity, hypertriglyceridaemia, and hyperglycaemia). Stepwise regression showed that serum FFA levels were an independent factor predicting advanced fibrosis (FIB-4 ≥ 1.3) in NAFLD patients. Serum FFA levels correlated with NAFLD and could be used as an indicator for predicting advanced fibrosis in NAFLD patients.