The roles of triglyceride/high-density lipoprotein cholesterol ratio and uric acid as predisposing factors for metabolic syndrome in healthy children

Triglyceride glucose index, pediatric NAFLD fibrosis index, and triglyceride-to-high-density lipoprotein cholesterol ratio are the most predictive markers of the metabolically unhealthy phenotype in overweight/obese adolescent boys

Introduction

The prevalence of obesity constantly increases worldwide and definitely increases the risk of premature death in early adulthood. While there is no treatment yet with proven efficacy for the metabolic clamp such as arterial hypertension, dyslipidemia, insulin resistance, diabetes type 2, and fatty liver disease, it is imperative to find a way to decrease cardiometabolic complications. Early prevention strategies beginning in childhood are the most logical step to reduce future cardiovascular morbidity and mortality. Therefore, the aim of the current study is to determine the most sensitive and specific predictive markers of the metabolically unhealthy phenotype with high cardiometabolic risk in overweight/obese adolescent boys.

Methods

This study was carried out at the Ternopil Regional Children's hospital (Western Ukraine) and involved 254 randomly chosen adolescent overweight or obese boys [median age was 16.0 (15.0,16.1) years]. A control group of 30 healthy children with proportional body weight comparable in gender and age to the main group was presented. A list of anthropometrical markers with biochemical values of carbohydrate and lipid metabolism with hepatic enzymes was determined. All overweight/obese boys were divided into three groups: 51.2% of the boys with metabolic syndrome (MetS) based on the IDF criteria; 19.7% of the boys were metabolically healthy obese (MHO) without hypertension, dyslipidemia, and hyperglycemia; and the rest of the boys (29.1%) were classified as metabolically unhealthy obese (MUO) with only one criterion (hypertension, dyslipidemia, or hyperglycemia).

Results

Based on multiple logistic regression analysis that included all anthropometric and biochemical values and calculated indexes in boys from the MHO group and MetS, it was revealed that the maximum likelihood in the prediction of MetS makes the combination of triglyceride glucose index, pediatric nonalcoholic fatty liver disease fibrosis index (PNFI), and triglyceride-to-high-density lipoprotein cholesterol ratio (R² =0.713, p<0.000). By tracing the receiver operating characteristic curve, the model is confirmed as a good predictor of MetS (AUC=0.898, odds ratio=27.111 percentage correct=86.03%) in overweight and obese boys.

Conclusion

Triglyceride glucose index, pediatric NAFLD fibrosis index, and triglyceride-to-high-density lipoprotein cholesterol ratio are a valuable combination of predictive markers of the metabolically unhealthy phenotype in Ukrainian overweight/obese boys.

Subcutaneous Adipose Tissue Transcriptome Highlights Specific Expression Profiles in Severe Pediatric Obesity: A Pilot Study

The prevalence of pediatric obesity is rising rapidly worldwide, and "omic" approaches are helpful in investigating the molecular pathophysiology of obesity. This work aims to identify transcriptional differences in the subcutaneous adipose tissue (scAT) of children with overweight (OW), obesity (OB), or severe obesity (SV) compared with those of normal weight (NW). Periumbilical scAT biopsies were collected from 20 male children aged 1-12 years. The children were stratified into the following four groups according to their BMI z-scores: SV, OB, OW, and NW. scAT RNA-Seq analyses were performed, and a differential expression analysis was conducted using the DESeq2 R package. A pathways analysis was performed to gain biological insights into gene expression. Our data highlight the significant deregulation in both coding and non-coding transcripts in the SV group when compared with the NW, OW, and OB groups. A KEGG pathway analysis showed that coding transcripts were mainly involved in lipid metabolism. A GSEA analysis revealed the upregulation of lipid degradation and metabolism in SV vs. OB and SV vs. OW. Bioenergetic processes and the catabolism of branched-chain amino acids were upregulated in SV compared with OB, OW, and NW. In conclusion, we report for the first time that a significant transcriptional deregulation occurs in the periumbilical scAT of children with severe obesity compared with those of normal weight or those with overweight or mild obesity.

Comparison of Diagnostic Models to Estimate the Risk of Metabolic Syndrome in a Chilean Pediatric Population: A Cross-Sectional Study

The pediatric population has various criteria for measuring metabolic syndrome (MetS). The diversity of consensus for diagnosis has led to different non-comparable reported prevalence. Given the increase in its prevalence in pediatric ages, it is necessary to develop efficient methods to encourage early detection. Consequently, early screening for the risk of MetS could favor timely action in preventing associated comorbidities in adulthood. This study aimed to establish the diagnostic capacity of models that use non-invasive (anthropometric) and invasive (serum biomarkers) variables for the early detection of MetS in Chilean children. A cross-sectional study was carried out on 220 children aged 6 to 11. Multivariate logistic regressions and discriminant analyses were applied to determine the diagnostic capacity of invasive and non-invasive variables. Based on these results, four diagnostic models were created and compared: (i) anthropometric, (ii) hormonal (insulin, leptin, and adiponectin), (iii) Lipid A (high-density cholesterol lipoprotein [HDL-c] and triglycerides [TG]) and (iv) Lipid B (TG/HDL-c). The prevalence of MetS was 26.8%. Lipid biomarkers (HDL-c and TG) and their ratio (TG/HDL-c) presented higher diagnostic capacity, above 80%, followed by body mass index (BMI, 0.71-0.88) and waist-to-height ratio (WHtR, 0.70-0.87). The lipid model A was the most accurate (sensitivity [S] = 62.7%, specificity [E] = 96.9%, validity index 87.7%), followed by the anthropometric model (S = 69.5%, E = 88.8% and validity index = 83.6%). In conclusion, detecting MetS was possible through invasive and non-invasive methods tested in overweight and obese children. The proposed models based on anthropometric variables, or serum biomarkers of the lipid model A, presented acceptable validity indices. Moreover, they were higher than those that measured adipokines, leptin, and adiponectin. The anthropometric model was the most cost-effective and easy to apply in different environments.

Association between Fasting and Postprandial Levels of Liver Enzymes with Metabolic Syndrome and Suspected Prediabetes in Prepubertal Children

Elevated liver enzyme activity may be associated with metabolic syndrome (MetS); however, it is not included in the MetS definition for children. Postprandial changes in the levels of biochemistry tests are related to manifestations of metabolic abnormalities. We assessed the association between fasting and postprandial liver enzymes levels with MetS and elevated hemoglobin A1c (HbA1c) in children aged 9-11. The study included 51 girls and 48 boys, all presumably healthy. In all participants' anthropometric indices, fasting glucose, insulin, lipid profile and HbA1c were measured. Enzymes, including alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT), were assayed in fasting and postprandial states. Individuals were divided into subgroups: with (MetS(+): n = 26); without MetS (MetS(-): n = 73); with HbA1c levels ≤ 5.3% (n = 39); and ≥5.7% (n = 11). Elevated fasting GGT levels were found in 23% of MetS(+) children and rarely in MetS(-) children; increased postprandial GGT was noted in 35% of MetS(+) individuals. Postprandial GGT changes tend to predict MetS (OR = 1.16; p = 0.092). Increased fasting ALT was found rarely in MetS(+) children, but did not occur in MetS(-) children. HbA1c ≥ 5.7% occurred rarely and neither fasting ALT nor GGT were related to elevated HbA1c. However, postprandial change of ALT was a good positive predictor of increased HbA1c (OR = 1.33; p = 0.021). Postprandial GGT performs better as an indicator of metabolic syndrome occurrence, and instead postprandial ALT may predict prediabetes in prepubertal children.

Comparison of Lipid-Derived Markers for Metabolic Syndrome in Youth: Triglyceride/HDL Cholesterol Ratio, Triglyceride-Glucose Index, and non-HDL Cholesterol

Triglyceride/high-density lipoprotein (HDL) cholesterol ratio (TG/HDL-C), triglyceride-glucose index (TyG), and non-HDL cholesterol level (non-HDL-C) have been proposed as surrogate markers for predicting metabolic syndrome (MetS). This study investigated whether these lipid-derived surrogate markers can predict MetS in Korean children and adolescents. Data from 1,814 participants were analyzed from the 2013-2016 Korean National Health and Nutrition Examination Survey. MetS was defined using three sets of criteria: Cook et al. (MetS1), de Ferranti et al. (MetS2), and the International Diabetes Federation (MetS3). The prevalence of MetS1, MetS2, and MetS3 was 4.6%, 11.3%, and 2.7%, respectively. In receiver operating characteristic curve analysis of MetS and lipid-derived surrogate markers, TG/HDL-C (0.937 for MetS1, 0.894 for MetS2, and 0.897 for MetS3) had the largest area under the curve (AUC), followed by TyG (0.906 for MetS1, 0.864 for MetS2, and 0.887 for MetS3), and non-HDL-C (0.752 for MetS1, 0.708 for MetS2, and 0.703 for MetS3) (all P < 0.001). The cutoff values for detecting MetS with TG/HDL-C, TyG, and non-HDL-C were 2.64, 8.52, and 111.6 for MetS1; 2.23, 8.47, and 110.7 for MetS2; and 2.64, 8.74, and 110.8 for MetS3, respectively. In conclusion, TG/HDL-C and TyG were similarly predictive of MetS. We propose using TG/HDL-C and TyG as surrogate markers for assessing MetS in Korean children and adolescents.

Association of the apoptotic marker APO1/Fas with children's predisposing factors for metabolic syndrome and with mean platelet volume

BACKGROUND

Apoptosis antigen 1/FAS receptor (APO1/Fas) signaling in endothelial cells plays a significant role in angiogenesis while increased mean platelet volume (MPV) is an important marker for platelet activation. We investigated the possible correlation between APO1/Fas and both metabolic parameters and platelet activity (indicated by the MPV) in a healthy pediatric population.

METHODS

One hundred and eighty-five children, aged 5-17 years old, were enrolled in the study. The participants were divided into subgroups according to their age and body mass index percentile (BMI%). APO1/Fas was measured by enzyme-linked immunosorbent assay (ELISA) and MPV by the MEK-6410K.

RESULTS

Eighty-one children (43.8%) had excess weight, which was more prevalent in children ≤9 years of age. Sixty-five children (35.1%) exhibited a predisposition for metabolic syndrome. A negative correlation was found between APO1/Fas and predisposing factors for metabolic syndrome: Glucose, cholesterol, uric acid, low-density lipoprotein (LDL), and triglycerides. In contrast, a positive correlation was found between APO1/Fas and C-reactive protein (CRP). Receiver operating characteristic (ROC) analysis showed a predisposition to metabolic syndrome when APO1/Fas was <78.46 pg/mL. A negative correlation was also observed between APO1/Fas and MPV. MPV was also positively correlated with predisposing factors for metabolic syndrome: BMI%, glucose, cholesterol, uric acid, LDL, and negatively with high-density lipoprotein.

CONCLUSIONS

APO1/Fas expression is associated with a lower predisposition to metabolic syndrome may be through endothelial homeostasis, the induction of apoptosis of cells involved in atherosclerosis, and platelet activity. It may also enhance CRP-mediated noninflammatory clearance of apoptotic cells. Early monitoring of all the components of metabolic syndrome in overweight children is important in order to prevent metabolic and cardiovascular complications.

The association of obstructive sleep apnea with dyslipidemia in Korean children and adolescents: a single-center, cross-sectional study

STUDY OBJECTIVES

To evaluate whether obstructive sleep apnea (OSA) and its severity are related to dyslipidemia and alanine transaminase elevation as a marker of nonalcoholic fatty liver disease in children.

METHODS

The data collected from polysomnography, laboratory measurements (lipid profile and liver enzyme), and body mass index in children aged 0-18 years who visited the pediatric department between 2012 and 2018 were retrospectively analyzed.

RESULTS

There were a total of 273 participants in the study (ages 0-6 years, 7-12 years, and 13-18 years: 61.9%, 26.4%, and 11.7%, respectively). In the ages 7-12 and 13-18 years groups, obesity was strongly associated with OSA severity (Cramer's V = 0.498, P < .001). High-density lipoprotein cholesterol levels were significantly lower in the OSA group than in the non-OSA group, irrespective of the presence of obesity. In addition, high-density lipoprotein cholesterol levels were significantly different between the OSA severity groups after adjusting for body mass index (P = .000). In participants who were obese, moderate and severe OSA were associated with alanine transaminase elevation (P = .023 and P = .045, respectively).

CONCLUSIONS

This study suggests that OSA may be an independent risk factor for dyslipidemia and that OSA and obesity have a synergistic effect on alanine transaminase elevation. Early diagnosis and treatment of OSA from childhood, especially in obese children, will reduce metabolic complications.

CITATION

Kang EK, Jang MJ, Kim KD, Ahn YM. The association of obstructive sleep apnea with dyslipidemia in Korean children and adolescents: a single-center, cross-sectional study. J Clin Sleep Med. 2021;17(8):1599-1605.

Management of severe pediatric obesity

Background: Pediatric obesity has increased over the decades, and in particular, severe pediatric obesity has become a serious public health problem. A concern has arisen that the COVID-19 pandemic may exacerbate the incidence of childhood obesity.Current Concepts: The consequences of severe pediatric obesity are more devastating than those of moderate obesity. Children with severe obesity are at a greater risk for hypertension, type 2 diabetes, metabolic syndrome, non-alcoholic fatty liver disease, atherosclerosis, and adult obesity. Correct assessment and diagnosis of a child with severe obesity is key to successful therapy. A thorough history and physical examination are important in identifying monogenic obesity or metabolic syndrome. Eating behaviors and psychosocial factors should be assessed to improve weight management outcomes. Treatment options for severe pediatric obesity include lifestyle modification, pharmacotherapy, and metabolic and bariatric surgery. Even though progress has been made with regard to the treatment of obesity, safe and effective treatment of severe pediatric obesity is challenging.Discussion and Conclusion: More efforts and innovations are needed to find a solution for the huge medical and emotional burden the children with severe obesity and their families are enduring.

Prevalence and treatment of pediatric dyslipidemia

Background: As dyslipidemia at a young age is a risk factor for cardiovascular disease in adulthood, the screening and management of dyslipidemia in children and adolescents might be an important health issue. This review deals with issues related to the prevalence, diagnosis, screening, and treatment of pediatric dyslipidemia.Current Concepts: In Korea, the prevalence of pediatric dyslipidemia was 19.7% between 2007 and 2009. Dyslipidemia was defined according to the guidelines of the Korean Society of Pediatric Endocrinology: total cholesterol ≥200 mg/dL, low-density lipoprotein cholesterol ≥130 mg/dL, triglycerides ≥130 mg/dL, high-density lipoprotein cholesterol <40 mg/dL, or non-high-density lipoprotein cholesterol ≥145 mg/dL.Discussion and Conclusion: We recommend universal screening tests for dyslipidemia at ages 9–11 years and 17–21 years. Diet and lifestyle modifications are essential in the treatment of dyslipidemia. In children aged ≥10 years with a poor response to lifestyle modification, drug therapy is recommended. Pediatric dyslipidemia should be diagnosed and treated properly to reduce adult cardiovascular diseases and improve quality of life in this age group.

Prediction of Insulin Resistance by Modified Triglyceride Glucose Indices in Youth

The triglyceride glucose (TyG) index, derived from a combination of fasting glucose and triglycerides, has been suggested as a useful marker for insulin resistance (IR), in addition to modified TyG indices that combine obesity parameters. This study investigated the association and utility of TyG and modified TyG indices for IR prediction in youth. Based on the Korea National Health and Nutritional Examination Survey, the data of 3728 youth aged 10–19 years were analyzed. Odds ratios (ORs) and 95% confidence intervals (CIs) of tertiles 2 and 3 for each parameter were calculated and compared with tertile 1 as a reference. To compare the parameters for identifying IR, receiver operating characteristic curves were plotted and the area under the curve (AUC) was calculated. The ORs and 95% CIs for insulin resistance (IR) progressively increased across tertiles of each parameter. Overall, all modified TyG indices presented higher ORs and AUC than the TyG index. The TyG-body mass index standard deviation score showed the largest AUC for IR detection in all subjects. In conclusion, TyG and modified TyG indices could be used as valuable markers for the prediction of IR in youth. Moreover, modified TyG indices had better diagnostic accuracy than the TyG index.

High uric acid promotes dysfunction in pancreatic β cells by blocking IRS2/AKT signalling

Hyperuricaemia is a disorder of purine metabolism. Elevated serum uric acid is strongly associated with many diseases, including gout, abdominal obesity, insulin resistance, and cardiovascular and kidney disease. Our previous studies showed that high uric acid (HUA) induced insulin resistance in several peripheral organs, including the liver, myocardium and adipose tissue. However, whether HUA directly induces insulin resistance of pancreatic β cells, the only source of insulin in the body and also a sensitive insulin target, is unknown. In this study, pancreatic β cells pretreated with HUA showed impaired insulin expression/secretion, glucose uptake and the glycolytic pathway. RNA-seq revealed that HUA affected the biological processes of INS-1 cells broadly, including oxidoreduction coenzyme metabolic process, pyruvate metabolic process, and glycolytic process. In addition, HUA reduced mitochondrial membrane potential and increased the production of reactive oxygen species(ROS) in INS-1 cells. INS-1 cells pretreated with probenecid, an organic anion transporter inhibitor, protected INS-1 cells against HUA-induced insulin secretion decrease, Pretreatment with N-acetyl-L-cysteine(NAC), a globally used antioxidant, recovered HUA-decreased insulin secretion and glucose uptake by pancreatic β cells. Insulin-like growth factor 1 (IGF-1), the phosphatidylinositol 3-kinase (PI3K) activator, rescues HUA-decreased insulin secretion by re-activating AKT phosphorylation. Thus, HUA induce insulin resistance, impaired insulin secretion and glycolytic pathway of pancreatic ꞵ cell through IRS2/AKT pathway.

Association of uric acid with cardiovascular risk in Brazilian children and adolescents

BACKGROUND AND AIM

Hyperuricemia in adults is associated with cardiovascular risk factors. However, there is less data regarding this association in children and adolescents. Our purpose was to determine association between serum uric acid (SUA) and cardiovascular risk.

METHODS AND RESULTS

A fasting blood sample was collected from 1750 participants aged 6-17 years enrolled in a social project and public schools in Espírito Santo, Brazil. Internal cut-offs were generated to define high SUA (≥90th percentile of SUA concentration for sex and age group). Body mass index percentile (pBMI), body fat percentage (BFP) and muscle mass were determined by bioimpedance. Data are given as mean ± standard deviation. High SUA was associated with overweight/obesity (OR 3.7 CI 95% 2.7-5.0), high waist circumference (WC) (OR 3.9 CI 95% 2.9-5.4), low HDL (OR 2.0 CI 95% 1.5-2.8), high blood pressure (BP) (OR 1.8 CI 95% 1.1-3.2), high BFP (OR 4.1 CI 95% 2.7-6.4), metabolic syndrome (MetS) (OR 3.6 CI 95% 1.8-7.1) and insulin resistance (OR 1.7 CI 95% 1.1-2.7). Individuals in the fourth quartile of SUA, compared to those in the first quartile, showed higher age, pBMI, WC, BFP and muscle mass. Using a reference value of 5.5 mg/dL, the prevalence of hyperuricemia in the sample was 10.3% (CI 95% 8.9-11.7%).

CONCLUSION

Higher SUA values are associated with higher cardiovascular risk in childhood and adolescence. The main cardiovascular risk factors associated with hyperuricemia were overweight/obesity, high WC, dyslipidemia, high BFP, high BP, insulin resistance and MetS.

Trends in Serum Lipid Profiles Among Korean Adolescents, 2007-2018

PURPOSE

An adverse lipid profile in adolescence often persists into adulthood, resulting in cardiovascular disease. We aimed to investigate the trends in the prevalence of adverse lipid profiles among Korean adolescents from 2007 to 2018.

PATIENTS AND METHODS

The data were obtained from 9044 adolescents aged 10-19 years who participated in the Korean National Health and Nutrition Examination Surveys (KNHANES) from 2007 to 2018. Fasting serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels were analyzed.

RESULTS

Significantly increasing trends in age-standardized prevalence of hypercholesterolemia [from 5.6% to 9.4% in boys (P = 0.004); from 8.1% to 12.4% in girls (P = 0.01)] and hyper-LDL-cholesterolemia [from 4.3% to 8.0% in boys (P = 0.003); from 6.6% to 9.7% in girls (P = 0.035)] were noted in both sexes. In contrast, the prevalence of hypo-HDL-cholesterolemia decreased significantly from 20.0% to 12.5% in boys (<0.001) and from 12.4% to 6.9% in girls (P < 0.001). There were no significant changes in the prevalence of hypertriglyceridemia and hyper-non-HDL-cholesterolemia in both sexes. Accordingly, the overall prevalence of dyslipidemia showed only a modest decline in boys (from 31.8% to 28.7%) and a stable trend in girls (from 28.9% to 28.2%).

CONCLUSION

The prevalence of hypercholesterolemia and hyper-LDL-cholesterolemia increased and that of hypo-HDL-cholesterolemia decreased among Korean adolescents over the recent 12 years. Further studies are needed to explain these trends and possible associations with lifestyle factors.