Metabolic risk-factor clustering estimation in obese children

Improving prediction algorithms for cardiometabolic risk in children and adolescents

Clustering of abnormal metabolic traits, the Metabolic Syndrome (MetS), has been associated with an increased cardiovascular disease (CVD) risk. Several algorithms including the MetS and other risk factors exist for adults to predict the risk of CVD. We discuss the use of MetS scores and algorithms in an attempt to predict later cardiometabolic risk in children and adolescents and offer suggestions for developing clinically useful algorithms in this population. There is little consensus in how to define the MetS or to predict future CVD risk using the MetS and other risk factors in children and adolescents. The MetS scores and prediction algorithms we identified had usually not been tested against a clinical outcome, such as CVD, and they had not been validated in other populations. This makes comparisons of algorithms impossible. We suggest a simple two-step approach for predicting the risk of adult cardiometabolic disease in overweight children. It may have advantages in terms of cost-effectiveness since it uses simple measurements in the first step and more complex, costly measurements in the second step. It also takes advantage of the continuous distributions of the metabolic features. We suggest piloting and validating any new algorithms.

Prevalence of insulin resistance and impaired glucose tolerance in a sample of obese Spanish children and adolescents

The prevalence of obesity in children has increased in developed countries in the last decades. It is associated with alterations in glucose metabolism that may be present in childhood. To assess the frequency of glucose metabolism alterations and insulin resistance and their possible determinants in a sample of obese children from Valladolid (Spain), we retrospectively studied 100 obese children and adolescents (11.59 ± 2.73 years). Anthropometric measures, biochemical parameters, and oral glucose tolerance test (OGTT) were performed. Insulin resistance was evaluated with fasting insulin, HOMA index, and insulin values in OGTT. Impaired glucose tolerance was found in 15% of the sample, and was the most frequent of glucose metabolism alterations. Impaired fasting glucose was found in 2%. No case of type 2 diabetes was found. Acanthosis nigricans was present in 22%, with predominance in females, but not all presented insulin resistance. The prevalence of insulin resistance was 29% when HOMA index was used, and 50% when the insulin response in OGTT was used. Not all patients with impaired glucose tolerance had a pathological HOMA index, and not all with pathological HOMA index presented insulin resistance when insulin values in OGTT were used. Higher 2-h post-OGTT insulin levels were found in children with impaired glucose tolerance. It is paramount to identify young people with glucose regulation alterations for early, intensive intervention to prevent or at least postpone the onset of type 2 diabetes. OGTT is a screening tool necessary to fulfill this objective.

[Obesity and cardiovascular risk factors in adolescents. Association with cardiovascular risk factors in first degree relatives]

BACKGROUND AND OBJECTIVE

Obesity is a major concern in public health. The fact that most teenagers stop contacting the health system during this period of life prevents detection of this problem and its associated morbidity. The aim of this study is to measure the prevalence of obesity at 18. We also aimed to detect overweight, cardiovascular risk factors (CVRF) and association with CVRF in parents and siblings.

PATIENTS AND METHOD

The research includes 153 children followed up to 18 years old in a community health center. Measures of body mass index (BMI), waist perimeter, CVRF, and familiar history were taken.

RESULTS

The prevalence of obesity in our study group was 7.18%, (IC: 3.0-11.0), (6.25% male and 7.86% female). The prevalence of overweight was 18.3% (IC: 11.9-24.0), (26.56% male and 12.35% female). A familiy history of CVRF was found in 53.9% (IC: 46.1-61.9) of cases, including high blood pressure (25%), obesity (23.6%), dyslipemia (21.7%), and diabetes (7.2%). This finding was more prevalent in the obesity group (72.72%) than in those with overweight only (64.2%), or with normal weight (49.59%). A family history of obesity and diabetes in first-degree relatives was associated to obesity in the study group. Also, a family history of high blood pressure was associated to the presence of high blood pressure in this group.

CONCLUSIONS

In order to detect obesity, overweight, and associated complications in young adults, specific attention to children and siblings of persons who present risk factors is recommended. Those with high blood pressure, diabetes or obesity have the higher risk.

Serum transaminases concentrations in obese children and adolescents

The aim of the study was to investigate the relationship between liver transaminase levels and metabolic syndrome (MS) features in obese children and adolescents. A total of 132 children and adolescents (73 males and 59 females) aged 8 - 16, participated in the study. All were studied at the department of Paediatrics, University Hospital of Zaragoza (Spain). Inclusion criteria were the existence of obesity as defined by body mass index (BMI) according to Cole cut-off values (when BMI was higher than the age and sex specific equivalent to 30 kg/m2). The definition of metabolic syndrome was according to the International Diabetes Federation criteria. Weight (kg), height (cm), waist circumference (cm), blood pressure and BMI were measured. Laboratory determinations after overnight fasting included: transaminases (ALT, AST, GGT), fasting glucose, insulin, triglycerides and HDL-C. The MS was found in 21.6% of the obese children and adolescents and the prevalence was higher in males (25.9%) than in females (15.9%). Serum transaminases (ALT, AST and GGT) mean concentrations were higher in males than in females, and decreased during pubertal development. The obese children and adolescents with the MS did not show higher transaminases concentrations when compared with those without the MS. Some MS manifestations (mainly waist circumference) showed a correlation with ALT, although all transaminases values were normal according to adult references. Liver transaminases, a surrogate marker of NAFLD, did not show an early and consistent manifestation of abnormalities in the obese children and adolescents studied. In order to define the presence of the disease, it would be necessary to obtain aminotransferase reference standards for children and adolescents, considering pubertal stage and gender.

Evaluation of AAP guidelines for cholesterol screening in youth: Project HeartBeat!

BACKGROUND

The American Academy of Pediatrics (AAP) criterion for screening for hypercholesterolemia in children is family history of hypercholesterolemia or cardiovascular disease or BMI > or =85th percentile. This paper aims to determine the sensitivity, specificity, and positive predictive value (PPV) of dyslipidemia screening using AAP criteria along with either family history or BMI.

METHODS

Height, weight, plasma total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, and family history were obtained for 678 children aged 8, 11, and 14 years, enrolled from 1991 to 1993 in Project HeartBeat!. Sensitivity, specificity, and PPV screening of each lipid component using family history alone, BMI > or =85th percentile alone, or family history and/or BMI > or =85th percentile, were calculated using 2008 AAP criteria (total cholesterol, LDL-C, and triglycerides > or =90th percentile; HDL-C <10th percentile).

RESULTS

Sensitivity of detecting abnormal total cholesterol, LDL-C, HDL-C, and triglycerides using family history alone ranged from 38% to 43% and significantly increased to 54%-66% using family history and/or BMI. Specificity significantly decreased from approximately 65% to 52%, and there were no notable changes in PPV. In black children, cholesterol screening using the BMI > or =85th percentile criterion had higher sensitivity than when using the family history criterion. In nonblacks, family history and/or BMI > or =85th percentile had greater sensitivity than family history alone.

CONCLUSIONS

When the BMI screening criterion was used along with the family history criterion, sensitivity increased, specificity decreased, and PPV changed trivially for detection of dyslipidemia. Despite increased screening sensitivity by adding the BMI criterion, a clinically significant number of children still may be misclassified.

On the use of a continuous metabolic syndrome score in pediatric research

Background

The constellation of elevated levels of abdominal adiposity, blood pressure, glucose, and triglycerides and lowered high-density lipoprotein-cholesterol has been termed the metabolic syndrome. Given the current pediatric obesity epidemic, it is perhaps not surprising that recent reports suggest the emergence of the metabolic syndrome during childhood and adolescence. The aim of this paper is to provide an overview of the derivation and utility of the continuous metabolic syndrome score in pediatric epidemiologic research.

Methods/Design

Data were generated from published papers related to the topic.

Conclusion

Although there is no universal definition in children or adolescence, recent estimates indicate that approximately 2–10% of youth possess the metabolic syndrome phenotype. Since there is no clear definition and the prevalence rate is relatively low, several authors have derived a continuous score representing a composite risk factor index (i.e., the metabolic syndrome score). This paper provides an overview of the derivation and utility of the continuous metabolic syndrome score in pediatric epidemiological research.

On the use of a continuous metabolic syndrome score in pediatric research

BACKGROUND

The constellation of elevated levels of abdominal adiposity, blood pressure, glucose, and triglycerides and lowered high-density lipoprotein-cholesterol has been termed the metabolic syndrome. Given the current pediatric obesity epidemic, it is perhaps not surprising that recent reports suggest the emergence of the metabolic syndrome during childhood and adolescence. The aim of this paper is to provide an overview of the derivation and utility of the continuous metabolic syndrome score in pediatric epidemiologic research.

METHODS/DESIGN

Data were generated from published papers related to the topic.

CONCLUSION

Although there is no universal definition in children or adolescence, recent estimates indicate that approximately 2-10% of youth possess the metabolic syndrome phenotype. Since there is no clear definition and the prevalence rate is relatively low, several authors have derived a continuous score representing a composite risk factor index (i.e., the metabolic syndrome score). This paper provides an overview of the derivation and utility of the continuous metabolic syndrome score in pediatric epidemiological research.