Prevalence of metabolic syndrome at age 16 using the International Diabetes Federation paediatric definition

Sleep duration is associated with metabolic syndrome in adolescents and children: a systematic review and meta-analysis

STUDY OBJECTIVES

Studies on the associations between sleep duration and metabolic syndrome in adolescents and children have reported mixed results. To shed more light on this issue, we conducted this meta-analysis by synthesizing the results of previous studies.

METHODS

Studies were retrieved from PubMed, Ovid, Cochrane, and Embase from inception to October 2021. Fixed-effects models and random-effects models were used to analyze the effects of sleep time on metabolic syndrome in adolescents.

RESULTS

Data from 7 studies, including 13,305 adolescents and children, were meta-analyzed. Compared with the control group, short sleep durations were not associated with a high prevalence of metabolic syndrome in adolescents and children using a random-effects model (odds ratio = 0.92, 95% confidence interval = 0.48-1.37, I2 = 56.5%, P = .378). Using a fixed-effects model on long sleep duration, this association was statistically significant (odds ratio = 0.57, 95% confidence interval = 0.38-0.76, I2 = 0.0%, P < .001) as a protective factor compared with shorter sleep duration.

CONCLUSIONS

Long sleep duration, instead of short sleep duration, was significantly associated with a lower prevalence of metabolic syndrome among adolescents and children.

CITATION

Xu Y, Hua J, Wang J, Shen Y. Sleep duration is associated with metabolic syndrome in adolescents and children: a systematic review and meta-analysis. J Clin Sleep Med. 2023;19(10):1835-1843.

Prevalence of Metabolic Syndrome among Children and Adolescents in High-Income Countries: A Systematic Review and Meta-Analysis of Observational Studies

Introduction. Metabolic syndrome (MetS) is an assemblage of interconnected cardiovascular risk factors that are prevalent among children and adolescents in high-income countries (HICs). Despite the presence of several studies on the issue, the study findings are incongruent due to the absence of a gold standard diagnostic method of MetS in children. Thus, the findings of the original studies are inconclusive for policy makers and other stakeholders. This systematic review and meta-analysis is aimed at giving conclusive evidence about MetS among children and adolescents in HICs. Methods. We conducted searches using electronic databases (PubMed, Scopus, Web of Science, CINAHL (EBSCOhost), EMBASE (Elsevier), and Medline (EBSCOhost)) and other sources (Google Scholar and Google) up to September 2020. Observational studies reporting the prevalence of MetS were eligible in this study. The pooled estimates were computed in fixed and random effect models using six diagnostic methods (IDF, ATP III, de Ferranti et al., WHO, Weiss et al., and Cruz and Goran). Publication bias was verified using funnel plots and Egger’s regression tests. Subgroup and sensitivity analysis were performed in case of higher heterogeneities among the included studies. Result. In this study, 77 studies with a total population of 125,445 children and adolescents were used in the final analysis. Metabolic syndrome among the overweight and obese population was computed from 28 studies with the pooled prevalence of 25.25%, 24.47%, 39.41%, 29.52%, and 33.36% in IDF, ATP III, de Ferranti et al., WHO, and Weiss et al. criteria, respectively. Likewise, 49 studies were eligible to compute the pooled prevalence of MetS in the general population of children and adolescents. Hence, MetS was found in 3.70% (IDF), 5.40% (ATP III), 14.78% (de Ferranti et al.), 3.90% (WHO), and, 4.66% (Cruz and Goran) of study participants. Regarding the components of MetS, abdominal obesity in the overweight and obese population, and low HDL-C in the general population were the most common components. Besides, the prevalence of Mets among males was higher than females. Conclusion. This study demonstrates that MetS among children and adolescents is undoubtedly high in HICs. The prevalence of MetS is higher among males than females. Community-based social and behavioral change communications need to be designed to promote healthy eating behaviors and physical activities. Prospective cohort studies could also help to explore all possible risk factors of MetS and to design specific interventions accordingly.

Novel Insights into the Pathogenesis and Management of the Metabolic Syndrome

The metabolic syndrome, by definition, is not a disease but is a clustering of individual metabolic risk factors including abdominal obesity, hyperglycemia, hypertriglyceridemia, hypertension, and low high-density lipoprotein cholesterol levels. These risk factors could dramatically increase the prevalence of type 2 diabetes and cardiovascular disease. The reported prevalence of the metabolic syndrome varies, greatly depending on the definition used, gender, age, socioeconomic status, and the ethnic background of study cohorts. Clinical and epidemiological studies have clearly demonstrated that the metabolic syndrome starts with central obesity. Because the prevalence of obesity has doubly increased worldwide over the past 30 years, the prevalence of the metabolic syndrome has markedly boosted in parallel. Therefore, obesity has been recognized as the leading cause for the metabolic syndrome since it is strongly associated with all metabolic risk factors. High prevalence of the metabolic syndrome is not unique to the USA and Europe and it is also increasing in most Asian countries. Insulin resistance has elucidated most, if not all, of the pathophysiology of the metabolic syndrome because it contributes to hyperglycemia. Furthermore, a major contributor to the development of insulin resistance is an overabundance of circulating fatty acids. Plasma fatty acids are derived mainly from the triglycerides stored in adipose tissues, which are released through the action of the cyclic AMP-dependent enzyme, hormone sensitive lipase. This review summarizes the latest concepts in the definition, pathogenesis, pathophysiology, and diagnosis of the metabolic syndrome, as well as its preventive measures and therapeutic strategies in children and adolescents.

Pediatric siMS score: A new, simple and accurate continuous metabolic syndrome score for everyday use in pediatrics

BACKGROUND

The dichotomous nature of the current definition of metabolic syndrome (MS) in youth results in loss of information. On the other hand, the calculation of continuous MS scores using standardized residuals in linear regression (Z scores) or factor scores of principal component analysis (PCA) is highly impractical for clinical use. Recently, a novel, easily calculated continuous MS score called siMS score was developed based on the IDF MS criteria for the adult population.

OBJECTIVE

To develop a Pediatric siMS score (PsiMS), a modified continuous MS score for use in the obese youth, based on the original siMS score, while keeping the score as simple as possible and retaining high correlation with more complex scores.

SUBJECTS AND METHODS

The database consisted of clinical data on 153 obese (BMI ≥95th percentile) children and adolescents. Continuous MS scores were calculated using Z scores and PCA, as well as the original siMS score. Four variants of PsiMS score were developed in accordance with IDF criteria for MS in youth and correlation of these scores with PCA and Z score derived MS continuous scores was assessed.

RESULTS

PsiMS score calculated using formula: (2xWaist/Height) + (Glucose(mmol/l)/5.6) + (triglycerides(mmol/l)/1.7) + (Systolic BP/130)-(HDL(mmol/l)/1.02) showed the highest correlation with most of the complex continuous scores (0.792-0.901). The original siMS score also showed high correlation with continuous MS scores.

CONCLUSION

PsiMS score represents a practical and accurate score for the evaluation of MS in the obese youth. The original siMS score should be used when evaluating large cohorts consisting of both adults and children.

Maternal Thyroid Antibodies Associates With Cardiometabolic Risk Factors in Children at the Age of 16

CONTEXT AND OBJECTIVE

The objective of this study was to determine the effects of maternal thyroid dysfunction or antibodies during pregnancy on the cardiometabolic risk factors in children.

DESIGN, SETTING, AND PARTICIPANTS

This prospective population-based cohort study, Northern Finland Birth Cohort 1986, included all pregnancies within a year in the area. Maternal serum samples were collected before the 20th week of gestation and analyzed for thyrotropin, free T4, thyroid-peroxidase antibodies (TPO-Abs), and thyroglobulin antibodies (Tg-Abs). Cardiometabolic risk factors in children at the age of 16 years were evaluated via blood sampling and clinical examination. Data were available for 3229 to 4176 mother-child pairs.

MAIN OUTCOME MEASURES

Waist circumference, blood pressure, lipids and lipoproteins, and insulin resistance were measured. Odds ratios (ORs) with 95% confidence intervals (CIs) of cardiometabolic risk factors in children with and without mothers with thyroid dysfunction or antibodies were calculated with logistic regression and adjusted for covariates.

RESULTS

Children of TPO-Ab-positive mothers had higher odds of metabolic syndrome (OR, 2.57; 95%, CI 1.26 to 5.25) and waist circumference indicative of metabolic syndrome (OR, 1.69; 95% CI, 1.14 to 2.50). They were also more likely to be overweight or obese (OR, 1.56; 95% CI, 1.04 to 2.34). Maternal thyroid dysfunction or Tg-Ab positivity did not associate with cardiometabolic risk factors in children.

CONCLUSION

Metabolic syndrome, greater waist circumference, and higher body mass index were more prevalent in children of TPO-Ab-positive mothers, indicating an adverse cardiovascular health profile.

An update on the assessment and management of metabolic syndrome, a growing medical emergency in paediatric populations

In the last decades the increasing rate of obesity in children and adolescents worldwide has led to the onset in paediatric age of metabolic syndrome, a disease commonly associated to adulthood. Central obesity, dyslipidaemia, hyperglycaemia, and hypertension are typical features of metabolic syndrome that seem to hesitate often in type 2 diabetes, cardiovascular disease, non-alcoholic fatty liver disease, and many other clinical conditions. Thus preventing and curing metabolic syndrome in paediatric patients is becoming an urgent need for public health. While diagnostic criteria and therapy of metabolic syndrome in adults are very well defined, there is no consensus on the definition of metabolic syndrome in children and adolescents as well as on healing approaches. The aim of this review is to describe the recent advances on the pathogenesis and clinical outcomes of paediatric metabolic syndrome. We then detail the therapeutic strategies (i.e. dietary regimens, physical exercise, nutraceuticals, and medications) employed to manage the disease. Finally, we analyse the safety profile of the drugs used in children and adolescents by performing a retrospective review of paediatric adverse reactions reported in the FDA's Adverse Event Reporting System database.

Metabolic syndrome in children and adolescents: Old concepts in a young population

Many years after first being described, there is still no clear consensus on diagnostic criteria for metabolic syndrome, particularly in children. However, identification of this cluster of cardiovascular risk factors especially in children with co-morbidities, is important in order to reduce their future risk of chronic disease and morbidity. Sustained multidisciplinary and family-based early intervention is required, aiming primarily at life-style change.

Utility of the hypertriglyceridemic waist phenotype in the cardiometabolic risk assessment of youth stratified by body mass index

BACKGROUND

It is unclear whether the hypertriglyceridemic waist phenotype (HTWP) can be used to identify those at most risk of cardiometabolic disorders.

OBJECTIVES

The utility of the HTWP as a useful predictor of cardiometabolic risk in youth stratified by body mass index was assessed.

METHODS

Three hundred and eighty-seven children (12-17.5 years) were used within this cross-sectional study. Participants were classified as normal weight or overweight/obese according to the International Obesity Task Force criteria. The HTWP phenotype was defined as having a waist circumference ≥90th percentile for age and gender with concomitant triglyceride concentrations ≥1.24 mmol L(-1) . Cardiometabolic risk profiles were compared using MANCOVA.

RESULTS

Normal weight participants with the HTWP had significantly higher levels of C-reactive protein 2.6 ± 0.4 vs. 1.6 ± 0.3 mg L(-1) (P < 0.05) and cardiometabolic risk scores (1.3 ± 0.3 vs. -0.7 ± 0.2 and 2.1 ± 0.4 vs. -0.5 ± 0.2; both P < 0.05) compared with those of a normal weight without the HTWP. Overweight/obese participants with the HTWP had significantly higher C-reactive protein levels (3.5 ± 0.6 vs. 2.6 ± 0.5; P < 0.05) as well as both cardiometabolic risk scores (1.6 ± 0.6 vs. 0.9 ± 0.2 and 2.2 ± 0.6 vs. 0.8 ± 0.2; both P < 0.001) when compared with overweight/obese participants without the HTWP.

CONCLUSIONS

The HTWP may serve as a simple and clinically useful approach to identify youth at increased cardiometabolic risk.

Metabolic syndrome in obese children and adolescents in Serbia: prevalence and risk factors

OBJECTIVE

To assess the prevalence of metabolic syndrome (MS) in obese children and adolescents in Serbia.

SUBJECTS AND METHODS

The study group consisted of 254 subjects (148 female and 106 male), aged 4.6-18.9 years with diet-induced obesity (body mass index ≥95th percentile). Presence of MS using the International Diabetes Federation definition was assessed in all subjects, as well as oral glucose tolerance test and insulin resistance indices.

RESULTS

Overall prevalence of MS in all subjects aged ≥10 years was 31.2%, namely, 28.7% in children aged 10 to <16 years and 40.5% in adolescents ≥16 years. When adjusted for age, gender and pubertal development, higher degree of obesity was a strong predictor of MS. Multivariate analysis showed that taller subjects and those with higher degree of insulin resistance were at significantly higher risk of MS, independent of the degree of obesity.

CONCLUSIONS

High prevalence of MS emphasizes the need for prevention and treatment of childhood obesity.

High cardiometabolic risk in healthy Chilean adolescents: associations with anthropometric, biological and lifestyle factors

OBJECTIVE

To analyse the prevalence of cardiovascular risk factors in healthy adolescents of low to middle socio-economic status and to study the influence of anthropometric, biological and lifestyle factors on the risk of metabolic syndrome (MetS).

DESIGN

Cross-sectional study. BMI, waist circumference, blood pressure, fat and lean mass (by dual-energy X-ray absorptiometry), TAG, HDL-cholesterol, glucose, insulin, homeostatic model assessment-insulin resistance index (HOMA-IR), food intake and physical activity were measured. Cardiovascular risk factors were defined using the International Diabetes Federation criteria and insulin resistance using HOMA-IR ≥2.6. Bivariate and multivariate regressions examined the associations between MetS and anthropometric, biological and lifestyle factors.

SETTING

Observational cohort study including Chilean adolescents, who were part of a follow-up study beginning in infancy.

SUBJECTS

Adolescents aged 16-17 years (n 667).

RESULTS

In the sample, 16.2% had obesity and 9.5% had MetS. Low HDL-cholesterol (69.9%), abdominal obesity (33.3%) and fasting hyperglycaemia (8.7%) were the most prevalent cardiovascular risk factors. In males, obesity (OR=3.7; 95% CI 1.2, 10.8), insulin resistance (OR=3.0; 95% CI 1.1, 8.2), physical inactivity (OR=2.9; 95% CI 1.1, 7.7) and sarcopenia (OR=21.2; 95% CI 4.2, 107.5) significantly increased the risk of MetS. In females, insulin resistance (OR=4.9; 95% CI 1.9, 12.6) and sarcopenia (OR=3.6; 95% CI 1.1, 11.9) were significantly associated with MetS.

CONCLUSIONS

High prevalences of obesity, abdominal obesity, dyslipidaemia, fasting hyperglycaemia and MetS were found in healthy adolescents. In both sexes, sarcopenia and insulin resistance were important risk factors of MetS. Promotion of active lifestyles at the school level and regulation of the sale of energy-dense foods are needed.

Cardiovascular risk factors in adolescents born preterm

BACKGROUND

Adolescents and adults born as small preterm infants show more pronounced risk factors of cardiovascular disease. Whether similar risks apply across all degrees of preterm birth is poorly known.

METHODS

We studied the association between preterm birth and cardiovascular risk factors in 6642 16-year-old adolescents of the population-based Northern Finland Birth Cohort 1986. Of these, 79 (1.2%) were born at <34 gestational weeks (early preterm), 238 (3.6%) at 34 to 36 weeks (late preterm), and 6325 at term (controls).

RESULTS

Girls born early preterm had 6.7 mm Hg (95% confidence interval: 3.1-10.2) higher systolic blood pressure (BP) and 3.5 mm Hg (1.1-5.8) higher diastolic BP, but no difference in serum lipid levels compared with control girls. Boys showed no differences in BP, but boys born early preterm had 6.7% (0.2%-13.7%) higher total cholesterol, 11.7% (2.1%-22.3%) higher low-density lipoprotein cholesterol, and 12.3% (3.1%-22.4%) higher apolipoprotein B concentrations. The differences were similar (BP) or stronger (lipids) when adjusted for maternal smoking, birth weight SD score, parental education, pubertal stage, BMI, and lifestyle. There were similar associations with length of gestation as a continuous variable. Accordingly, mean differences between late preterm and controls were in the same direction but weaker, although most were not statistically significant.

CONCLUSIONS

Preterm birth was associated with elevated BP in adolescent girls and an atherogenic lipid profile in boys. Because these associations were strongest among those born early preterm, our findings are consistent with a dose-response relationship between shorter length of gestation and cardiovascular risk factors.

Metabolic syndrome in children and adolescents from Mérida city, Venezuela: Comparison of results using local and international reference values (CREDEFAR study)

OBJECTIVE

To obtain local reference values for blood lipids and blood pressure (BP), and to determine the prevalence of metabolic syndrome (MS) in children and adolescents from Mérida, Venezuela, and to compare results using local and international cut-off values.

MATERIALS AND METHODS

The study enrolled 916 participants of both sexes aged 9-18 years of age from educational institutions. Demographic, anthropometric, and BP data were collected. Fasting blood glucose and lipid profile were measured. Percentile distribution of lipid and BP values was done by age group and sex. Prevalence of MS was estimated based on the NCEP-ATPIII classification (as modified by Cook et al.) and the classification of the International Diabetes Federation, using percentiles of Mérida and the USA as cut-off points. Agreement between both classifications was estimated using the kappa test (κ).

RESULTS

Prevalence of MS was 2.2% by Cook-Merida percentiles, as compared to 1.8% by Cook-USA percentiles, a moderate agreement (κ=0.54). Agreement between Cook et al. and IDF using Merida percentiles was weak (κ=0.28). There was a higher frequency of abdominal obesity, hypertriglyceridemia and hypertension, and a lower frequency of low HDL-C using Mérida percentiles. The risk (odds ratio) of having MS is greater if abdominal obesity exists (OR: 98.63, CI: 22.45-433.35, p=0.0001). MS was significantly more common in obese subjects (18.3%, p=0.0001).

CONCLUSIONS

Prevalence of MS in this sample of children and adolescents was 2.2%. Lipid and BP values were lower in Venezuelan as compared to US, European, and Asian children and adolescents, and similar to those in Latin-American references. Own reference values are required for accurate diagnosis of MS, as well as a worldwide consensus on its diagnostic criteria.

Association between obesity and metabolic co-morbidities among children and adolescents in South Korea based on national data

Background

Childhood obesity has become a serious public health threat worldwide due to its many short- and long-term adverse health effects. We assessed the association between weight status and metabolic co-morbidities among South Korean children using nationally representative data.

Methods

Data from the 2007-2008 Korea National Health and Nutrition Examination Surveys for 1,526 children aged 10-19 years were used. Logistic regression models were fit to examine the association between weight status [overweight, 85^th percentile ≤ BMI <95^th percentile; obese, BMI ≥95^th percentile; and central obesity, waist circumference ≥90^th percentile, based on 2007 Korean National Growth Charts] and metabolic outcomes.

Results

More obese children had metabolic co-morbidities than normal-weight children (P < 0.05). Boys had higher means BMI than girls, WC, and BP, while girls had higher means of total blood cholesterol and HDL-cholesterol (P < 0.05). Attributable risk of metabolic syndrome was high due to overweight and obesity: 91.1% for central obesity and 29.6% for high TG. Obese children had increased risk of having high BP (adjusted odds ratio (OR): 1.90; 95% CI: 1.05-3.45), dyslipidemia (OR: 6.21; 95% CI: 3.59-10.75), high TG (OR: 6.87; 95% CI: 4.05-11.64), low HDL (OR: 4.46; 95% CI: 2.23-8.89), and ≥2 co-morbidities (OR: 26.97; 95% CI: 14.95-48.65) compared to normal-weight subjects, while the associations between weight status and metabolic outcomes were stronger in boys.

Conclusions

Obesity was strongly associated with metabolic co-morbidities in South Korean children.

The prevalence of metabolic syndrome in children: a systematic review of the literature

BACKGROUND

Metabolic syndrome has been identified as a condition of childhood relatively recently. The aim in this study was to describe the prevalence of metabolic syndrome in children allowing for differences in metabolic syndrome definitions.

METHODS

This was a systematic review of the OVID, EMBASE, and CINAHL databases, capturing details of overall prevalence and prevalence within groups categorized by obesity, gender, age, and ethnicity.

RESULTS

In all, 378 studies published since 2003 were identified, and of these 85 papers were included in the present review. When all studies were considered, the median prevalence of metabolic syndrome in whole populations was 3.3% (range 0%-19.2%), in overweight children was 11.9% (range 2.8%-29.3%), and in obese populations was 29.2% (range 10%-66%). Within-study analyses confirmed higher prevalence for obese compared to overweight (P=0.012) and obese compared to nonobese, nonoverweight children (P<0.001). Within-study analyses also revealed higher median metabolic syndrome prevalence for boys compared to girls (5.1% versus 3.0%, P<0.001) and also in older compared with younger children (5.6% versus 2.9%, P=0.001). Limited evidence was found to suggest differences between ethnic groups, and there were insufficient studies to determine whether metabolic syndrome prevalence was increasing over time.

CONCLUSIONS

This is the first systematic review of all of the relevant literature. It describes the magnitude of associations between metabolic syndrome and obesity, age, and gender. We find evidence that ethnicity and geography may be important to metabolic syndrome prevalence in children and these associations require further study.

The absence of insulin resistance in metabolic syndrome definition leads to underdiagnosing of metabolic risk in obese patients

This study explores in a group of obese children and adolescents aged 10 to 16 years, the prevalence of metabolic syndrome (MS) according to the criteria of International Diabetes Federation (IDF). In addition, the prevalence of insulin resistance (IR) was investigated to find correlations between MS and IR. IDF definition was compared to a modified WHO definition. A total of 159 obese patients (74 male and 85 female; median age 12.7 years) were included in the study. Anthropometric measurements, blood pressure, and serum fasting lipids were evaluated. An oral glucose tolerance test (OGTT) was performed, and serum glucose and insulin levels were measured at 0, 30, 60, 90, and 120 min. Homeostasis model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), fasting glucose/insulin ratio (FGIR), Matsuda index, and total insulin levels during OGTT were calculated. For the IR diagnosis, we used cutoff values described in previous publications (HOMA-IR of >3.16, QUICKI of <0.357, FGIR of <7, and/or the sum of insulin levels during OGTT of >300 mIU/mL). MS prevalence, defined according to IDF criteria, was 34.6 %. Using the IDF definition, there was no statistically significant difference for the surrogate IR indices between patients with or without MS (QUICKI, 94.5 vs. 83.7 %), FGIR (81.1 vs. 78.8 %), HOMA-IR (70.9 vs. 63.5 %), and total insulin levels during OGTT (61.8 vs. 51.9 %). The Matsuda index values, the prevalence of fasting hyperinsulinemia, and impaired glucose tolerance were also similar in these two groups. In conclusion, IR was prominent in obese patients with and without MS. IDF definition of MS fails to discover individuals with IR, unless it is specifically investigated.

Does sleep duration predict metabolic risk in obese adolescents attending tertiary services? A cross-sectional study

STUDY OBJECTIVES

To determine, in a clinical sample of obese adolescents, whether shorter sleep duration is associated with metabolic risk and obesity severity.

DESIGN

Cross-sectional study.

SETTING

Tertiary care weight-management clinic in Cincinnati, OH, USA.

PARTICIPANTS

133 obese adolescents aged 10-16.9 years.

INTERVENTIONS

N/A.

MEASUREMENTS

Multifaceted sleep duration data were examined with fasting venipuncture and anthropometric data collected during clinical care.

PRIMARY OUTCOME

presence of metabolic syndrome.

SECONDARY OUTCOMES

waist circumference, triglycerides, HDL-cholesterol, blood pressure, glucose, insulin resistance (HOMA-IR), and body mass index (BMI).

PREDICTORS

Sleep duration by (1) parent-report, (2) self-report, and (3) multi-night actigraphy.

ANALYSIS

Relationships between sleep duration and each outcome were examined via regression models, adjusted for potential confounders.

RESULTS

Regardless of how measured, sleep duration showed no strong association with metabolic syndrome (OR 1.1 to 1.5, P = 0.2 to 0.8), BMI (β -0.03 to -0.01, P = 0.2 to 0.8), or most other outcomes. Lower triglycerides were predicted by shorter sleep duration by self-report (β 12.3, P = 0.01) and actigraphy (β 13.6, P = 0.03), and shorter parent-reported sleep duration was associated with higher HDL-cholesterol (β = -2.7, P = 0.002).

CONCLUSIONS

Contrary to expectations, sleep duration was not associated with metabolic outcomes, and showed limited associations with lipid profiles. Although inadequate sleep may affect other areas of functioning, it appears premature to expect that lengthening sleep will improve BMI or metabolic outcomes in clinical samples of obese adolescents.

Incidence and trend of a metabolic syndrome phenotype among Tehranian adolescents: findings from the Tehran Lipid and Glucose Study, 1998-2001 to 2003-2006

OBJECTIVE

To assess the incidence and trend of the metabolic syndrome phenotype in adolescents from the Tehran Lipid and Glucose Study during 3.6 years of follow-up.

RESEARCH DESIGN AND METHODS

A total of 932 adolescents, aged 10-19 years, who had complete data and returned for reassessment 3.6 years later were investigated.

RESULTS

Prevalence of metabolic syndrome at baseline and after 3.6 years was 7.4 and 6.7%, respectively, based on the Adult Treatment Panel (ATP) III definitions; 3.5 and 8.0%, respectively, based on the International Diabetes Federation (IDF) definitions; 4.1 and 9.4%, respectively, based on the American Heart Association (AHA) definitions; and 13.6 and 13.4%, respectively, based on the National Health and Nutrition Examination Survey (NHANES) definitions. Incidence rates were 5.2% (95% CI 3-6) based on ATP III, 6.8% (5-8) based on IDF, 8.3% (6-10) based on AHA, and 8.8% (6-10) based on NHANES definitions.

CONCLUSIONS

Incidence of metabolic syndrome is high in Tehranian adolescents.

Dietary and lifestyle counselling reduces the clustering of overweight-related cardiometabolic risk factors in adolescents

AIM

The aim of this study was to evaluate the impact of individualised dietary and lifestyle counselling, primarily aimed to decrease serum low-density lipoprotein cholesterol, on the clustering of overweight-related cardiometabolic risk factors in children.

DESIGN AND PARTICIPANTS

The 7-month-old study children were randomized either to counselling (n = 540) or control group (n = 522).

MAIN OUTCOME MEASURES

The 5- to 15-year-old participants who fulfilled the international criteria were classified as overweight. Being in the highest [lowest for high-density lipoprotein (HDL) cholesterol] age- and gender-specific quintile of body mass index (BMI), blood pressure, serum triglycerides, HDL cholesterol or glucose was considered a risk factor. A cluster was defined as having high BMI and > or = 2 other risk factors.

RESULTS

The counselling did not reduce the prevalence of overweight in 5- to 15-year-old participants. From age 7 onwards, the proportion of children with > or = 2 risk factors was lower in the intervention than in the control group (p = 0.005). At the age of 15 years, 13.0% of girls and 10.8% of boys in the intervention group and 17.5% of girls and 18.8% of boys in the control group had the risk factor cluster (p = 0.046 for main effect of the study group). Having even one risk factor at the age of 5 years predicted the clustering of risk factors at the age of 15 years (OR: 3.8, p < 0.001).

CONCLUSION

Repeated, individualized dietary and lifestyle counselling may reduce the clustering of overweight-related cardiometabolic risk factors in adolescents even though the counselling is not intense enough to prevent overweight.

Behind and beyond the pediatric metabolic syndrome

The growing use of the Metabolic Syndrome in pediatric age need a critical approach, on the basis of recent concerns on definition and usefulness for individual management in clinical practice. We reviewed these aspects from a pediatric point of view, providing a set of questions about what the Metabolic Syndrome means in a clinical setting. The new proposed pediatric definition by IDF was discussed, by outlying how it does not fully consider the peculiarities of children and adolescents. The comparison between two cases of obese children was used in order to show how this diagnosis could be confusing for a correct management. We stressed the need for health-related limits for each component of the Metabolic Syndrome instead of percentile-derived cut-points, as well as the opportunity to extend the estimation to other family or individual risk factors by means of a multiple-items screening form. In conclusion, Metabolic Syndrome use in pediatric age suffers at present from important limitations (i.e., adult derived definition, possibility to rule-in but not to rule-out the individual metabolic risk, instability of MetS during adolescence, poor usefulness of the diagnosis for specific treatment). Consequently, a prudent use of Metabolic Syndrome for children and adolescents seems to be the best and honest position for paediatricians, waiting for long term, longitudinal follow-up studies that could clarify the entire question.

Metabolic syndrome in the pediatric population: a short overview

The metabolic syndrome (MS) in adults is defined as a concurrence of obesity, disturbed glucose and insulin metabolism, hypertension and dyslipidemia, and is associated with increased morbidity and mortality from cardiovascular diseases and type 2 diabetes. Studies now indicate that many of its components are also present in children and adolescents. Moreover, the clustering of these risk factors has been documented in some children, who are at increased cardiovascular risk in adulthood. The MS is highly prevalent among overweight children and adolescents. Identifying these children is important for early prevention and treatment of different components of the syndrome. The first-line treatment comprises lifestyle modification consisting of diet and exercise. The most effective tool for prevention of the MS is to stop the development of childhood obesity. The first attempt at consensus-based pediatric diagnostic criteria was published in 2007 by the International Diabetes Federation. Nevertheless, national prevalence data, based on uniform pediatric definition, protocols for prevention, early recognition and effective treatment of pediatric MS are still needed.The aim of this article is to provide a short overview of the diagnosis and treatment options of childhood MS, as well as to present the relationships between MS and its individual components.

Adolescent manifestations of metabolic syndrome among children born to women with gestational diabetes in a general-population birth cohort

The association between maternal gestational diabetes (GDM) and manifestations of metabolic syndrome among Caucasian adolescents was studied with data from the population-based Northern Finland 1986 Birth Cohort. This is a longitudinal cohort study from early pregnancy until offspring age 16 years and includes data from a risk group-based GDM screen of pregnant mothers by an oral glucose tolerance test. Metabolic outcomes were compared between the offspring of women with GDM (OGDM; n = 95) and reference group offspring (n = 3,909). The prevalence of overweight was significantly higher in the OGDM group (18.8 vs. 8.4%; P < 0.001) than in the reference group. The median body mass index (20.8 vs. 20.2 kg/m(2), 95% confidence interval (CI) for the percentage difference adjusted for sex: 3.5%, 9.5%), waist circumference (73.3 vs. 71.5 cm, 95% CI: 3.2%, 7.5%), and fasting insulin (10.20 vs. 9.30 milliunits/L, 95% CI: 5.9%, 26.0%) were higher, and homeostatic model assessment-insulin sensitivity (74.7 vs. 82.3, 95% CI: -20.6%, -5.4%) was lower in the OGDM group. These differences were similar after an additional adjustment for birth weight and gestational age. The differences in waist circumference, insulin, and homeostatic model assessment-insulin sensitivity were attenuated but remained statistically significant after additional adjustment for body mass index at 16 years. These findings highlight the importance of prevention strategies among children born to women with GDM.

Prevalence and correlates of the metabolic syndrome in a population-based sample of European youth

BACKGROUND

Until recently, there has been no unified definition of the metabolic syndrome (MetS) in the youth. Therefore, the prevalence of MetS and its association with potential correlates are largely unknown.

OBJECTIVE

The objective was to quantify the prevalence, identify the correlates, and examine the independent associations between potential correlates with MetS.

DESIGN

A population-based cohort study was conducted in 10- and 15-y-old youth from Estonia, Denmark, and Portugal (n = 3193). MetS was defined according to the International Diabetes Federation. Correlates included maternal socioeconomic status, body mass index (BMI), hypertension, and prevalent diabetes and maternally reported child's birth weight and duration of breastfeeding. Data on sexual maturity, objectively measured physical activity, cardiorespiratory fitness, self-reported sports participation, television viewing, and regular play were collected for the children.

RESULTS

The prevalence of MetS was 0.2% and 1.4% in 10- and 15-y-olds, respectively. Cardiorespiratory fitness (standardized odds ratio: 0.33; 95% CI: 0.15, 0.75), physical activity (standardized odds ratio: 0.40; 95% CI: 0.18, 0.88), and maternal BMI (standardized odds ratio: 1.61; 95% CI: 1.11, 2.34) were all independently associated with MetS after adjustment for sex, age group, study location, birth weight, and sexual maturity. An increase in daily moderate-intensity physical activity by 10-20% was associated with a 33% lower risk of being categorized with MetS.

CONCLUSIONS

High maternal BMI and low levels of cardiorespiratory fitness and physical activity independently contribute to the MetS and may be targets for future interventions. Relatively small increases in physical activity may significantly reduce the risk of MetS in healthy children.