The structure of metabolic syndrome components across follow-up survey from childhood to adolescence

Definition and early diagnosis of metabolic syndrome in children

With this review, we aim to focus the attention on some established as well as new concepts for the metabolic syndrome (MetS) in children and adolescents spanning from definition to recommendations for the diagnostic approach. Even though there is no international commonly used definition of the metabolic syndrome in children and adolescents, all definitions include obesity as precondition for the development of MetS even in children. Obesity is one of the major cardiometabolic risk factors and it is strongly linked to other metabolic diseases like hyperlipidemia, hyperinsulinemia as well as hypertension. The metabolic syndrome is commonly known as a constellation of the mentioned morbidities. Pediatricians and researchers agree that early diagnosis and early interventions of the MetS are important to improve the prevention of cardiovascular disease and type 2 diabetes in adulthood. However, this requires appropriate screening tools for children and adolescents at risk for the MetS and its comorbidities. Due to controversies regarding the definition of MetS and the lack of consensus thresholds for the single components in children and adolescents, there is no internationally accepted diagnostic pathway for MetS available. However, several consensus statements and national guidelines for the assessment of obesity and its comorbidities in children and adolescents are available. Obesity seems to be the driving factor for the development of the other risk factors of MetS. In order to avoid conflicts concerning the definition of overweight and obesity, we recommend using the WHO definition of overweight (one standard deviation body mass index for age and sex and obesity; two standard deviations body mass index for age and sex) in children and adolescents.

Metabolic Syndrome: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

In recent decades, investigations have been focused on the definition, incidence and predictors of metabolic syndrome (MetS) in Iranians. This study aimed to review systematically investigations on MetS, conducted among the Tehran lipid and glucose study (TLGS) participants.

EVIDENCE ACQUISITION

Literature on MetS documented by TLGS studies published from 2000 to 2017 were searched using Pubmed and Scopus database in English language with a combination of following keywords: Metabolic syndrome, TLGS.

RESULTS

The harmonized definition of MetS was confirmed, based on the estimated cut point of waist circumference (WC) ≥ 95 cm for both genders in Iran. The incidence rate was 550.9/10000 person/years, lower among women (433.5/10000) than men (749.2/10000). The prevalence of abdominal obesity, high triglycerides (TG), low high density lipoprotein cholesterol (HDL-C), high blood pressure (BP), and high fasting blood glucose (FBG) was 30, 46, 69, 34, and 12%, respectively. The prevalence of MetS in adolescents was 10.1% with no significant difference between boys and girls (10.3% in boys and 9.9% in girls). A strong association of WC (OR: 2.32, CI: 2.06 - 2.59) and TGs (OR: 1.95, CI: 1.65 - 2.11) with development of MetS was found. In adolescent boys, WC had the highest OR for MetS risk. WHO-defined MetS was a significant predictor of total and cardiovascular mortality both in men (HR: 1.66, CI: 1.23 - 2.24; HR:1.93, CI: 1.26 - 2.94) and women (HR: 2.01, CI: 1.39 - 2.88; HR:2.71, CI: 1.44 - 5.09).

CONCLUSIONS

Our results indicate high incidence of MetS in Tehranian adults and adolescents; high WC also appears to be a strong predictor of MetS. All definitions of MetS predicted cardiovascular disease.

Association of serum lead and mercury level with cardiometabolic risk factors and liver enzymes in a nationally representative sample of adolescents: the CASPIAN-III study

This study aims to determine the difference of serum Pb and Hg levels in adolescents with or without metabolic syndrome (MetS) and the association of serum levels of these heavy metals with cardiometabolic risk factors and liver enzymes in Iranian adolescents. The study population consisted of 320 adolescents (160 with MetS and 160 healthy controls). The relationship between serum heavy metals and cardiometabolic risk factors was assessed by linear regression. The odds ratios (OR) of having metabolic syndrome across Pb and Hg quartiles were determined by multiple logistic regression analysis. The mean (SD) of Pb and Hg concentrations were higher in adolescents with MetS than in those without it (0.83 (0.27) and 0.17 (0.01) vs. 0.65 (0.15) and 0.10 (0.08) μg/L, P = 0.01 and 0.0001, respectively). Increase in serum Pb and Hg was associated with increase in some cardiometabolic risk factors. Among boys and girls, diastolic blood pressure (DBP), fasting blood glucose, total cholesterol (TC), triglycerides (TG), and alanine aminotransaminase increased significantly across quartiles of serum Pb. Among girls, SBP, DBP, TC, and TG had a significant increase across Hg quartiles. The corresponding figure among boys was significant for SBP, DBP, and TG. Higher quartiles of Pb increased the risk of having MetS (OR 95 % CI 3.10, 2.25-4.27), the corresponding figure was 2.03, 1.75-3.16, across Hg quartiles. Our study showed significant associations between serum Pb and Hg levels with cardiometabolic risk factors in adolescents. In future surveys, the role of potential confounders should be considered more extensively. The clinical significance of these findings needs to be confirmed in longitudinal studies. By considering the origins of chronic diseases from early life, controlling environmental pollutants should be considered as a health priority for primordial or primary prevention of noncommunicable diseases.

Metabolic syndrome in Spanish adolescents and its association with birth weight, breastfeeding duration, maternal smoking, and maternal obesity: a cross-sectional study

PURPOSE

The metabolic syndrome (MetS) in adolescents is a growing problem. The objectives were to verify the association among early predictors such as birth weight, breastfeeding, maternal weight status, smoking during pregnancy, and the development of MetS.

METHODS

A cross-sectional study was performed of 976 children and adolescents, 10-15 years of age, at schools in the provinces of Granada and Almeria (Spain). For this purpose, we analyzed the physical characteristics as well as the biochemical markers of the participants with a view to ascertaining the prevalence of the MetS. Relevant data were also extracted from the clinical histories of their mothers.

RESULTS

It was found that 3.85% of the female subjects and 5.38% of the male subjects in the sample population suffered from MetS. In both sexes, there was an association between birth weight and positive MetS diagnosis (OR 1.27). For both males and females, there was an inverse association between the length of time that they had been breastfed and positive MetS diagnosis (OR1-3 months 3.16; OR4-6 months 1.70; OR(>6 months) 0.13). There was also a significant association between maternal weight (OR(overweight )30.79; OR(obesity) 49.36) and cigarette consumption during pregnancy (OR 1.47) and the subsequent development of MetS in the children of these mothers.

CONCLUSIONS

Those subjects born with a higher than average birth weight had a greater risk of developing MetS in childhood and adolescence. Breastfeeding children for longer than 6 months protected them from MetS in their early years as well as in their teens. Other risk factors for MetS were maternal smoking during pregnancy as well as maternal overweight and obesity.