Glucose metabolism in children and adolescents: Population-based reference values and comparisons to children and adolescents enrolled in obesity treatment

Associations of adiponectin concentrations from birth until late adolescence with insulin resistance

INTRODUCTION

We investigated associations of adiponectin concentrations from birth to adolescence with insulin resistance in late adolescence using data from Project Viva prospective birth cohort (Eastern Massachusetts, 1999-2002).

METHODS

We conducted multivariable linear regression models between adiponectin (internal z-scores) at birth, early childhood, mid-childhood, early and late adolescence and insulin resistance in late adolescence with the homeostasis model for insulin resistance (HOMA-IR).

RESULTS

In 468 children (52% female, 59% Non-Hispanic White), we observed inverse associations of adiponectin z-scores in mid-childhood (-0.16, 95% CI: -0.33, 0.01), early adolescence (-0.19, 95% CI: -0.37, -0.01) and late adolescence (-0.40, 95% CI: -0.57, -0.23) with HOMA-IR in late adolescence; these associations were attenuated after accounting for BMI z-score. When stratified by sex, we observed these associations in males, while estimates were more modest in females.

CONCLUSION

Overall, starting in mid-childhood, lower adiponectin concentrations were linked with higher insulin resistance in late adolescence, with associations apparent mostly in males.

Genetic factors shaping the plasma lipidome and the relations to cardiometabolic risk in children and adolescents

BACKGROUND

Lipid species are emerging as biomarkers for cardiometabolic risk in both adults and children. The genetic regulation of lipid species and their impact on cardiometabolic risk during early life remain unexplored.

METHODS

Using mass spectrometry-based lipidomics, we measured 227 plasma lipid species in 1149 children and adolescents (44.8% boys) with a median age of 11.2 years. We performed genome-wide association analyses to identify genetic variants influencing lipid species. Colocalisation and Mendelian randomisation (MR) analyses were performed to infer causality between lipid species and cardiometabolic outcomes.

FINDINGS

We identified 37 genome-wide significant loci for 52 lipid species, nine of which are previously unreported. Colocalisation analyses revealed that seven lipid loci shared genetic variants associated with adult cardiometabolic outcomes. One-sample MR analysis identified positive causal associations between ceramides and liver enzymes, sphingomyelins and hemoglobin A1c (HbA1c), and phosphatidylethanolamines and high-sensitivity C-reactive protein in children and adolescents. Two-sample MR using adult-based summary statistics showed consistent direction of associations and indicated additional causal links, specifically between ceramides and elevated HbA1c levels, and phosphatidylinositols with elevated liver enzymes.

INTERPRETATION

These findings highlight the potential long-term implications of plasma lipid genetic determinants on cardiometabolic risk.

FUNDING

Novo Nordisk Foundation, The Innovation Fund Denmark, The Danish Heart Foundation, EU Horizon, and LundbeckFonden.

Nonpharmacological Childhood Obesity Management in Denmark Reduces Steatotic Liver Disease and Obesity

Background: Steatotic liver disease (SLD) represents a multisystem disease and is a common complication of childhood obesity. We studied fat content at the abdominal level (liver, subcutaneous, and visceral) and the response to childhood obesity management. Methods: In this retrospective longitudinal study, 8-18-year-olds with a body mass index (BMI) z-score above 1.28 (corresponding to a BMI above the 90th percentile), as a proxy for obesity, were offered person-centered, family-oriented obesity management in a hospital setting and in a magnetic resonance (MR) scan. Liver fat content (LFC) was assessed by MR spectroscopy, whereas subcutaneous adipose tissue and visceral adipose tissue (VAT) were assessed by MR imaging. We conducted nonparametric tests to evaluate baseline-to-follow-up changes and comparisons between participants with and without an MR assessment. Additionally, a logistic regression model examined the association between changes in LFC and BMI z-score. Results: The study group comprised 1002 children and adolescents (52% females) with an MR assessment at baseline. The median age was 13.0 years, the median BMI was 28.4, and the BMI z-score was 2.90. At baseline, 378 (38%) exhibited SLD defined by an LFC above 1.5%. Among the 322 with a follow-up MR scan, 76% of the patients with SLD reduced their LFC. BMI z-score and VAT (both p < 0.001) were reduced during intervention. Conclusions: SLD is highly prevalent (38%) in children and adolescents with obesity. A chronic care obesity management model reduced the fat content in the liver, the visceral fat, and the degree of obesity.

Cardiorespiratory Fitness and Body Mass Index as Predictors of Metabolic Syndrome in Schoolchildren (PACH Study)

Purpose

Metabolic syndrome (MetS) has become a condition not rarely diagnosed in children and adolescents, leading to changes in physical and mental health. Simple and cost-effective screening methods applied in schools are needed to take preventive measures and reduce the risk of the development of MetS in children.

Methods

This prospective longitudinal study aims to investigate the prevalence of MetS and its risk factors in 8-10-year-old schoolchildren (46 boys and 60 girls) over 3 consecutive years. General Linear Mixed Model (GLMM) was used to assess the effect of recommended daily levels of moderate to vigorous physical activity (MVPA), body mass index (BMI), waist circumference (WC), cardiorespiratory fitness (CRF), and obesity level on a new set of orthogonal variables formed from various parameters of MetS (eg blood pressure (BP), lipid panel and glucose homeostasis) determined by Principal Component Analysis (PCA).

Results

The prevalence of MetS was 2% in the years 2017, 2018 and 2019, while in 2020 prevalence reached 7.7%. The most prevalent combination of criteria defining MetS syndrome in children was increased WC, BP, and blood triglycerides (TG). PCA identified non-high-density lipoprotein (non-HDL), low-density lipoprotein (LDL), and total cholesterol (TCHOL) as important predictors of metabolic syndrome (MetS). Additionally, cardiorespiratory fitness (CRF) and body mass index (BMI) were found to significantly influence the variance in MetS criteria. However, moderate to vigorous physical activity (MVPA) did not have a notable effect on the variance of these criteria.

Conclusion

The prevalence of MetS in children is increasing with age. Non-HDL turned out to be the most influential parameter across all principal components. The CRF, being accessible, simple to use, non-invasive and cost-effective, proved to be a superior predictor of variance of glucose homeostasis compared to BMI.

An adult-based genetic risk score for liver fat associates with liver and plasma lipid traits in children and adolescents

BACKGROUND & AIMS

Genome-wide association studies have identified steatogenic variants that also showed pleiotropic effects on cardiometabolic traits in adults. We investigated the effect of eight previously reported genome-wide significant steatogenic variants, individually and combined in a weighted genetic risk score (GRS), on liver and cardiometabolic traits, and the predictive ability of the GRS for hepatic steatosis in children and adolescents.

APPROACH & RESULTS

Children and adolescents with overweight (including obesity) from an obesity clinic group (n = 1768) and a population-based group (n = 1890) were included. Cardiometabolic risk outcomes and genotypes were obtained. Liver fat was quantified using 1 H-MRS in a subset of 727 participants. Variants in PNPLA3, TM6SF2, GPAM and TRIB1 were associated with higher liver fat (p < .05) and with distinct patterns of plasma lipids. The GRS was associated with higher liver fat content, plasma concentrations of alanine transaminase (ALT), aspartate aminotransferase (AST) and favourable plasma lipid levels. The GRS was associated with higher prevalence of hepatic steatosis (defined as liver fat ≥5.0%) (odds ratio per 1-SD unit: 2.17, p = 9.7E-10). A prediction model for hepatic steatosis including GRS alone yielded an area under the curve (AUC) of 0.78 (95% CI 0.76-0.81). Combining the GRS with clinical measures (waist-to-height ratio [WHtR] SDS, ALT, and HOMA-IR) increased the AUC up to 0.86 (95% CI 0.84-0.88).

CONCLUSIONS

The genetic predisposition for liver fat accumulation conferred risk of hepatic steatosis in children and adolescents. The liver fat GRS has potential clinical utility for risk stratification.

High Plasma Levels of Soluble Lectin-like Oxidized Low-Density Lipoprotein Receptor-1 Are Associated With Inflammation and Cardiometabolic Risk Profiles in Pediatric Overweight and Obesity

Background Lectin-like oxidized low-density lipoprotein (ox-LDL) receptor-1 is a scavenger receptor for oxidized low-density lipoprotein. In adults, higher soluble lectin-like ox-LDL receptor-1 (sLOX-1) levels are associated with cardiovascular disease, type 2 diabetes, and obesity, but a similar link in pediatric overweight/obesity remains uncertain. Methods and Results Analyses were based on the cross-sectional HOLBAEK Study, including 4- to 19-year-olds from an obesity clinic group with body mass index >90th percentile (n=1815) and from a population-based group (n=2039). Fasting plasma levels of sLOX-1 and inflammatory markers were quantified, cardiometabolic risk profiles were assessed, and linear and logistic regression analyses were performed. Pubertal/postpubertal children and adolescents from the obesity clinic group exhibited higher sLOX-1 levels compared with the population (P<0.001). sLOX-1 positively associated with proinflammatory cytokines, matrix metalloproteinases, body mass index SD score, waist SD score, body fat %, plasma alanine aminotransferase, serum high-sensitivity C-reactive protein, plasma low-density lipoprotein cholesterol, triglycerides, systolic and diastolic blood pressure SD score, and inversely associated with plasma high-density lipoprotein cholesterol (all P<0.05). sLOX-1 positively associated with high alanine aminotransferase (odds ratio [OR], 1.16, P=4.1 E-04), insulin resistance (OR, 1.16, P=8.6 E-04), dyslipidemia (OR, 1.25, P=1.8 E-07), and hypertension (OR, 1.12, P=0.02). Conclusions sLOX-1 levels were elevated during and after puberty in children and adolescents with overweight/obesity compared with population-based peers and associated with inflammatory markers and worsened cardiometabolic risk profiles. sLOX-1 may serve as an early marker of cardiometabolic risk and inflammation in pediatric overweight/obesity. Registration The HOLBAEK Study, formerly known as The Danish Childhood Obesity Biobank, ClinicalTrials.gov identifier number NCT00928473, https://clinicaltrials.gov/ct2/show/NCT00928473 (registered June 2009).

Hyperglucagonemia in Pediatric Adiposity Associates With Cardiometabolic Risk Factors but Not Hyperglycemia

CONTEXT

In adults, hyperglucagonemia is associated with type 2 diabetes, impaired glucose tolerance, and obesity. The role of glucagon in pediatric overweight/obesity remains unclear.

OBJECTIVE

We examined whether fasting concentrations of glucagon are elevated in youth with overweight/obesity and whether this associates with cardiometabolic risk profiles.

METHODS

Analyses were based on the cross-sectional HOLBAEK study, including children and adolescents 6 to 19 years of age, with overweight/obesity from an obesity clinic group (n = 2154) and with normal weight from a population-based group (n = 1858). Fasting concentrations of plasma glucagon and cardiometabolic risk outcomes were assessed, and multiple linear and logistic regressions models were performed.

RESULTS

The obesity clinic group had higher glucagon concentrations than the population-based group (P < 0.001). Glucagon positively associated with body mass index (BMI) standard deviation score (SDS), waist, body fat %, liver fat %, alanine transaminase (ALT), high-sensitivity C-reactive protein, homeostasis model assessment of insulin resistance, insulin, C-peptide, LDL-C, triglycerides, SDS of diastolic and systolic blood pressure, and was inversely associated with fasting glucose. The inverse relationship between glucagon and glucose was attenuated in individuals with high BMI SDS and high fasting insulin. Glucagon was associated with a higher prevalence of insulin resistance, increased ALT, dyslipidemia, and hypertension, but not with hyperglycemia. Glucagon was positively associated with fasting total glucagon-like peptide-1.

CONCLUSION

Compared with normal weight peers, children and adolescents with overweight/obesity had elevated concentrations of fasting glucagon, which corresponded to worsened cardiometabolic risk outcomes, except for hyperglycemia. This suggests hyperglucagonemia in youth may precede impairments in glucose regulation.

Fasting C-peptide values among adolescents in the National Health and Nutrition Examination Surveys

AIM

To report fasting C-peptide values and variations across demographics in healthy non-diabetic adolescents included in the National Health and Nutrition Examination Surveys (NHANES) dataset.

RESEARCH DESIGN AND METHODS

In this analysis, we used fasting C-peptide data from the 1999 to 2004 NHANES dataset for participants aged 12 to <18 years (n = 2063).

RESULTS

The mean ± SE age of the participants was 14.99 ± 0.06 years. The participants included 992 girls and 1071 boys, and more than 80% of participants had a body mass index (BMI) percentile of <85%. Among boys, the most notable finding was the increase in geometric mean C-peptide level from 0.51 nmol/L at age 12, to 0.65 nmol/L at age 15 years. Among girls, levels fluctuated around a geometric mean of 0.67 nmol/L. Girls had significantly higher mean log-transformed C-peptide concentrations than boys (P < 0.0001) after adjusting for age, race and BMI percentile category. After adjusting for age and BMI percentile category, non-Hispanic Black boys and girls had significantly lower C-peptide levels than non-Hispanic White (P = 0.0026 and P = 0.0093) and Mexican American boys and girls (P < 0.0001 and P < 0.0001), respectively. Despite these findings, both insulin and homeostatic model assessment of insulin resistance were greater in non-Hispanic Black compared to non-Hispanic White participants.

CONCLUSIONS

Here we describe fasting C-peptide levels in a non-diabetic adolescent population. These data provide crucial insight into evaluating racial differences in endogenous insulin release and clearance and will provide novel information which can be used in assessing residual β-cell function and response to intervention therapy.

Fasting Plasma GLP-1 Is Associated With Overweight/Obesity and Cardiometabolic Risk Factors in Children and Adolescents

CONTEXT

The importance of fasting glucagon-like peptide-1 (GLP-1) in altered metabolic outcomes has been questioned.

OBJECTIVE

This work aimed to assess whether fasting GLP-1 differs in children and adolescents with overweight/obesity compared to a population-based reference, and whether concentrations predict cardiometabolic risk (CMR) factors.

METHODS

Analyses were based on The Danish Childhood Obesity Data- and Biobank, a cross-sectional study including children and adolescents, aged 6 to 19 years, from an obesity clinic group (n = 1978) and from a population-based group (n = 2334). Fasting concentrations of plasma total GLP-1 and quantitative CMR factors were assessed. The effects of GLP-1 as a predictor of CMR risk outcomes were examined by multiple linear and logistic regression modeling.

RESULTS

The obesity clinic group had higher fasting GLP-1 concentrations (median 3.3 pmol/L; interquartile range, 2.3-4.3 pmol/L) than the population-based group (2.8 pmol/L; interquartile range, 2.1-3.8 pmol/L; P < 2.2E-16). Body mass index SD score (SDS), waist circumference, and total body fat percentage were significant predictors of fasting GLP-1 concentrations in boys and girls. Fasting GLP-1 concentrations were positively associated with homeostasis model assessment of insulin resistance, fasting values of insulin, high-sensitivity C-reactive protein, C-peptide, triglycerides, alanine transaminase (ALT), glycated hemoglobin A1c, and SDS of diastolic and systolic blood pressure. A 1-SD increase in fasting GLP-1 was associated with an increased risk of insulin resistance (odds ratio [OR] 1.59), dyslipidemia (OR 1.16), increased ALT (OR 1.14), hyperglycemia (OR 1.12) and hypertension (OR 1.12).

CONCLUSION

Overweight/obesity in children and adolescents is associated with increased fasting plasma total GLP-1 concentrations, which was predictive of higher CMR factors.

Risk of gestational diabetes mellitus in nulliparous women - Associations with early life body size and change in body mass index from childhood to adulthood

AIMS

We examined whether a woman's birthweight, childhood height, body mass index (BMI), and BMI changes from childhood to pregnancy were associated with risks of gestational diabetes mellitus (GDM).

METHODS

We studied 13,031 women from the Copenhagen School Health Records Register born 1959-1996 with birthweight and measured anthropometric information at ages 7 and/or 13. The diagnosis of GDM (n = 255) was obtained from a national health register. Risk ratios (RR) were estimated using log-linear binomial regression.

RESULTS

Own birthweight and childhood height were inversely associated with GDM. Girls with overweight at age 7 had a higher risk of GDM than girls with normal-weight (RR: 1.79, 95% CI: 1.31, 2.47). Compared to women with normal-weight in childhood and adulthood, risks of GDM were higher in women who developed overweight from age 7 to pregnancy (RR: 4.62; 3.48, 6.14) or had overweight at both times (RR: 4.71; 3.24, 6.85). In women whose BMI normalized from age 7 to pregnancy the RR for GDM was 1.08 (0.47, 2.46).

CONCLUSIONS

Lower birthweight, shorter childhood height, and higher childhood BMI are associated with increased risks of GDM. Efforts to help girls maintain a normal BMI before pregnancy may be warranted to minimize risks of GDM.

High prevalence of undiagnosed comorbidities among adolescents with obesity

Metabolic diseases are increasing among adolescents with obesity. Although the reported prevalence of metabolic syndrome is approximately 30% worldwide, its prevalence is largely unknown among New Zealand adolescents. Therefore, we assessed the health of adolescents with obesity (BMI ≥ 30 kg/m2) enrolled in a randomised clinical trial (Gut Bugs Trial), to identify the prevalence of undiagnosed comorbidities. Assessments included anthropometry, 24-h ambulatory blood pressure monitoring, and insulin sensitivity. We report on baseline data (pre-randomisation) on 87 participants (14-18 years; 59% females), with mean BMI 36.9 ± 5.3 kg/m2 (BMI SDS 3.33 ± 0.79). Approximately 40% of participants had undiagnosed metabolic syndrome, which was twice as common among males. Half (53%) had pre-diabetes and 92% a reduction in insulin sensitivity. Moreover, 31% had pre-hypertension/hypertension, 69% dyslipidaemia, and 25% abnormal liver function. Participants with class III obesity had a greater risk of metabolic syndrome than those with classes I/II [relative risk 1.99 (95% CI 1.19, 3.34)]. Risks for pre-hypertension/hypertension and inflammation were also greater among those with class III obesity. We identified a high prevalence of undiagnosed comorbidities among adolescents with obesity in New Zealand. As adolescent obesity tracks into adulthood, early interventions are needed to prevent progression to overt cardiometabolic diseases.

Low-grade inflammation independently associates with cardiometabolic risk in children with overweight/obesity

BACKGROUND AND AIMS

Pediatric obesity associates with both low-grade inflammation and cardiometabolic risk on the population level. Yet on an individual patient level, overweight/obesity does not always equal increased cardiometabolic risk. In this study, we examine whether low-grade inflammation associates with cardiometabolic risk in Danish children, independent of degree of adiposity. We further assess the value of integrating multiple inflammation markers to identify children with very-high cardiometabolic risk profiles.

METHOD AND RESULTS

We studied 2192 children and adolescents aged 6-18 years from an obesity clinic cohort and a population-based cohort, in a cross-sectional study design. Anthropometry, blood pressure, pubertal stage and body composition by dual-energy X-ray absorptiometry were assessed, and biomarkers including fasting serum high sensitivity C-reactive protein (hsCRP), white blood cells (WBC), resistin, lipid profile and glucose metabolism were measured. Adjusted correlation analysis and odds ratios were calculated. We found that, independent of degree of adiposity, having high-normal inflammation marker concentrations associated with increased cardiometabolic risk: for girls, hsCRP >0.57-9.98 mg/L (mid/upper tertile) associated with ~2-fold higher odds of dyslipidemia and hepatic steatosis (vs. lower tertile). For both sexes, WBC >7.0-12.4 10⁹/L (upper tertile) associated with 2.5-fold higher odds of insulin resistance. Lastly, children with multiple inflammation markers in the high-normal range exhibited the most severe cardiometabolic risk profile.

CONCLUSION

Low-grade inflammation associates with cardiometabolic risk in children independent of degree of adiposity. The associations vary with sex and inflammation marker measured. Finally, integrating multiple low-grade inflammation markers identifies a very-high-risk subgroup of children with overweight/obesity and may have clinical value.

Changes in Thyroid and Glycemic Status and Food Intake in Children with Excess Weight Who Were Submitted for a Multi-Component School Intervention for 16 Months

We investigated if children with excess weight who submitted to two types of intervention at school for 16 months showed improvements in thyroid and glycemic function and food intake. Children (8-11 years) with a body mass index-for-age (BMI/A) of ≥1 Z score were divided into two groups: Treatment 1 (n = 73) involved motivation to adopt healthier lifestyle; Treatment 2 (n = 103) involved performing weekly nutritional education, motivational, and physical activities at school. A semi-quantitative food frequency questionnaire was used. The delta BMI/A were similar after 16 months; Treatment 1 showed higher decrease in thyroid-stimulating hormone (TSH; median (range)): -0.45 (-3.19 to 2.17) and 0.06 (-4.57 to 1.63) mIU/L, p = 0.001), FreeT3 (-0.46 (-2.92 to 1.54) and -0.15 (-2.46 to 1.38) pmol/L, p = 0.038), and FreeT4 -1.41 (-6.18 to 3.47) and -0.90 (-4.89 to 2.96) pmol/L, p = 0.018), followed by decrease in energy intake (7304 (6806 to 7840) and 8267 (7739 to 8832) kJ, Ptreatment = 0.439, Ptime <0.001, interaction group-time p < 0.001), macronutrients and sugar. A positive correlation between FreeT3 and BMI/A, and a negative correlation with FreeT4 and insulin were found at baseline (r 0.212, p < 0.01; r -0.155, p < 0.01, respectively) and follow-up (r 0.222, p < 0.01; r -0.221, p < 0.01). The decrease in overall diet and particularly sugar intake was accompanied by a greater reduction in TSH and FreeT3 in Treatment 1, demonstrating the impact of dietary intake on thyroid function.

Leptin, adiponectin, and their ratio as markers of insulin resistance and cardiometabolic risk in childhood obesity

BACKGROUND

It is imperative to develop markers for risk stratification and detection of cardiometabolic comorbidities in children with obesity. The adipokines leptin and adiponectin are both involved in fat mass regulation and the development of obesity-related disorders; furthermore, their ratio (leptin/adiponectin ratio) is suggested to be associated with insulin resistance and cardiometabolic risk.

OBJECTIVE

To evaluate associations between fasting serum concentrations of the adipokines (total leptin and adiponectin as well as the L/A ratio) and cardiometabolic comorbidities in children with overweight/obesity.

METHODS

A total of 2258 children with overweight/obesity or normal weight aged 6 to 18 years were studied. Differences in anthropometrics and adipokine concentrations were tested using Wilcoxon rank-sum test. Associations between the adipokines and cardiometabolic risk were tested using Spearman's correlation and logistic regression, adjusted for age and body mass index SD score (BMI-SDS).

RESULTS

Compared to normal weight children; children with overweight/obesity exhibited higher leptin concentrations, lower adiponectin concentrations, and higher L/A ratios. After adjusting for age and degree of obesity, girls with overweight/obesity in the upper quartile range for the L/A ratio, when compared with girls in the lower quartile range, were more likely to have insulin resistance (odds ratio [OR]: 7.78 [95% confidence interval [CI], 3.78-16.65]), dysglycemia (OR: 3.08 [95% CI, 1.35-7.31]), and dyslipidemia (OR: 2.53 [95% CI, 1.18-5.59]); while boys were more likely to have insulin resistance (OR: 4.45 [95% CI, 2.03-10.10]).

CONCLUSIONS

Independent of the degree of obesity, leptin, adiponectin, and the L/A ratio were associated with insulin resistance and other cardiometabolic comorbidities in children with overweight/obesity, but the L/A ratio exhibited stronger associations than the respective adipokines.