New pediatric percentiles of liver enzyme serum levels (alanine aminotransferase, aspartate aminotransferase, γ-glutamyltransferase): Effects of age, sex, body mass index, and pubertal stage.

The present study aims to clarify the effects of sex, age, body mass index (BMI), and puberty on transaminase serum levels in children and adolescents and to provide new age- and sex-related percentiles for alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyltransferase (GGT). Venous blood and anthropometric data were collected from 4,126 cases. Excluded were cases of participants with potential hepatotoxic medication, with evidence of potential illness at the time of blood sampling and non-normal BMI (BMI <10th or >90th). The resulting data (N = 3,131 cases) were used for the calculations of ALT, AST, and GGT percentiles. Age- and sex-related reference intervals were established by using an LMS method of Cole-type method. Serum levels of transaminases follow age-specific patterns and relate to the onset of puberty. This observation is more pronounced in girls than in boys. ALT percentiles showed similar-shaped patterns in both sexes. Multivariate regression confirmed significant effects of puberty and BMI-SDS (ß = 2.21) on ALT. Surprisingly, AST serum levels were negatively influenced by age (ß = -1.42) and BMI-SDS (ß = -0.15). GGT percentiles revealed significant sex-specific differences, correlated positively with age (ß = 0.37) and showed significant association with BMI-SDS (ß = 1.16). CONCLUSION: Current reference values of ALT, AST, and GGT serum levels were calculated for children between 11 months and 16.0 years, using modern analytical and statistical methods. This study extends the current knowledge about transaminases by revealing influences of age, sex, BMI, and puberty on serum concentrations of all three parameters and has for these parameters one of the largest sample sizes published so far. (Hepatology 2017).

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.

Relations between sleep duration with overweight and academic stress-just a matter of the socioeconomic status?

OBJECTIVES: Shorter sleep duration in childhood has already been associated with health-related and psychological factors, such as overweight/obesity or stress. This study investigates associations of sleep duration with overweight/obesity and stress related to academic success in school ("academic stress") in dependence on children's socioeconomic status. DESIGN: Cross-sectional. SETTING: LIFE Child Study, a study investigating child development from pregnancy to adulthood. PARTICIPANTS: A total of 1537 (2325 observations) 1- to 14-year-old children were considered. Analyses on academic stress were performed in a subgroup of 450 school-aged children (631 observations). MEASUREMENTS: Associations between sleep duration and overweight/obesity as well as academic stress were analyzed using linear mixed-effect regression models controlling for multiple visits. Importantly, all associations were checked for interactions with families' socioeconomic status. RESULTS: The analyses revealed negative associations between sleep duration and overweight/obesity as well as academic stress, which, however, were only observable in children from families with a low socioeconomic status. The associations were consistent across all ages. CONCLUSIONS: The findings suggest that children from families with a low socioeconomic status have a higher susceptibility for risk factors promoting sleep deficiency, overweight, or academic stress, for example, unhealthy food intake, high media consumption, or the loss of coping strategies for academic stress at school.

Age- and Sex-Related Percentiles of Skinfold Thickness, Waist and Hip Circumference, Waist-to-Hip Ratio and Waist-to-Height Ratio: Results from a Population-Based Pediatric Cohort in Germany (LIFE Child).

BACKGROUND: Skinfold thickness (ST), waist circumference (WC) and hip circumference (HC) measurements are simple methods for assessing fat tissue at defined body parts. We examined these parameters in a cohort of healthy children and adolescents in Leipzig. Our study provides current percentile curves for biceps, triceps, subscapular and iliac crest ST, plus WC, HC, waist-to-hip ratio and waist-to-height ratio. METHODS: 6,344 visits were recorded involving 2,363 individuals from 3 to 16 years in age. Continuous age- and gender-related percentiles (3rd, 10th, median, 90th, 97th percentiles) were estimated using Cole's LMS method. RESULTS: For biceps and triceps ST, boys show a peak at the beginning of adolescence with a subsequent decrease, while percentile values among girls rise across the age range. Subscapular and iliac crest percentiles also show increasing curves with disproportionately high values for P90 and P97. Boys show higher values of WC, girls have higher levels of HC. WC and HC median percentiles constantly increase in both sexes with a plateau at the age of 16 for girls. CONCLUSION: Trends for all parameters of body fat are in line with other national and international studies. Unlike the KiGGS study, our study provides circumference data across the whole of our age range, i.e. from 3 to 16 years.

Novel Insights in the Metabolic Syndrome in Childhood and Adolescence.

Metabolic syndrome (MetS) is recognized as an escalating major health risk in adults as well as in children and adolescents. Its prevalence ranges from 6 to 39% depending on the applied definition criteria. To date, there is no consensus on a MetS definition for children and adolescents. However, most authors agree on essential components such as glucose intolerance, central obesity, hypertension, and dyslipidemia; each representing a risk for cardiovascular disease. Recently, associations between MetS and non-alcoholic fatty liver disease, hyperuricemia, and sleep disturbances have emerged. Biomarkers like adipocytokines are a subject of current research as they are implicated in the pathogenesis of the MetS. Epigenetics and gestational programming, especially the role of microRNA, comprise a novel, rapidly developing and promising research focus on the topic of MetS. MicroRNAs are increasingly valued for potential roles in the diagnosis, stratification, and therapeutics of MetS. Early detection of risk factors, screening for metabolic disturbances, and the identification of new therapies are major aims to reduce morbidity and mortality related to MetS. Dietary modification and physical activity are currently the only adopted treatment approaches. Pharmacological therapies and bariatric surgery are still contradictory and, therefore, are only recommended in selected high-risk cases.