Pediatric Features of Genetic Predisposition to Polycystic Ovary Syndrome.

CONTEXT: Polycystic ovary syndrome (PCOS) has historically been conceptualized as a disorder of the reproductive system in women. However, offspring of women with PCOS begin to show metabolic features of PCOS in childhood, suggestive of childhood manifestations. OBJECTIVE: To identify childhood manifestations of genetic risk for PCOS. METHODS: We calculated a PCOS polygenic risk score (PRS) for 12 350 girls and boys in 4 pediatric cohorts-ALSPAC (UK), COPSAC (Denmark), Project Viva (USA), and The HOLBÆK Study (Denmark). We tested for association of the PRS with PCOS-related phenotypes throughout childhood and with age at pubarche and age at peak height velocity and meta-analyzed effects across cohorts using fixed-effect models. RESULTS: Higher PRS for PCOS was associated with higher body mass index in midchildhood (0.05 kg/m2 increase per 1 SD of PRS, 95% CI 0.03, 0.07, P = 3 × 10-5) and higher risk of obesity in early childhood (OR 1.34, 95% CI 1.13, 1.59, P = .0009); both persisted through late adolescence (P all ≤.03). Higher PCOS PRS was associated with earlier age at pubarche (0.85-month decrease per 1 SD of PRS, 95% CI -1.44, -0.26, P = .005) and younger age at peak height velocity (0.64-month decrease per 1 SD of PRS, 95% CI -0.94, -0.33, P = 4 × 10-5). CONCLUSION: Genetic risk factors for PCOS are associated with alterations in metabolic, growth, and developmental traits in childhood. Thus, PCOS may not simply be a condition that affects women of reproductive age but, rather, a possible manifestation of an underlying condition that affects both sexes starting in early life.

Genetics of Plasma Bilirubin and Associations between Bilirubin and Cardiometabolic Risk Profiles in Danish Children and Adolescents.

Bilirubin is the end product of heme catabolism, mainly produced by the breakdown of mature red blood cells. Due to its anti-inflammatory, antioxidant, antidiabetic, and antilipemic properties, circulating bilirubin concentrations are inversely associated with the risk of cardiovascular disease, type 2 diabetes, and all-cause mortality in adults. Some genetic loci associated with circulating bilirubin concentrations have been identified by genome-wide association studies in adults. We aimed to examine the relationship between circulating bilirubin, cardiometabolic risk factors, and inflammation in children and adolescents and the genetic architecture of plasma bilirubin concentrations. We measured fasting plasma bilirubin, cardiometabolic risk factors, and inflammatory markers in a sample of Danish children and adolescents with overweight or obesity (n = 1530) and in a population-based sample (n = 1820) of Danish children and adolescents. Linear and logistic regression analyses were performed to analyze the associations between bilirubin, cardiometabolic risk factors, and inflammatory markers. A genome-wide association study (GWAS) of fasting plasma concentrations of bilirubin was performed in children and adolescents with overweight or obesity and in a population-based sample. Bilirubin is associated inversely and significantly with a number of cardiometabolic risk factors, including body mass index (BMI) standard deviation scores (SDS), waist circumference, high-sensitivity C-reactive protein (hs-CRP), homeostatic model assessment for insulin resistance (HOMA-IR), hemoglobin A1c (HbA1c), low-density lipoprotein cholesterol (LDL-C), triglycerides, and the majority of measured inflammatory markers. In contrast, bilirubin was positively associated with fasting plasma concentrations of alanine transaminase (ALT), high-density lipoprotein cholesterol (HDL-C), systolic blood pressure (SDS), and the inflammatory markers GH, PTX3, THBS2, TNFRSF9, PGF, PAPPA, GT, CCL23, CX3CL1, SCF, and TRANCE. The GWAS showed that two loci were positively associated with plasma bilirubin concentrations at a p-value threshold of <5 × 10-8 (rs76999922: ß = -0.65 SD; p = 4.3 × 10-8, and rs887829: ß = 0.78 SD; p = 2.9 × 10-247). Approximately 25% of the variance in plasma bilirubin concentration was explained by rs887829. The rs887829 was not significantly associated with any of the mentioned cardiometabolic risk factors except for hs-CRP. Our findings suggest that plasma concentrations of bilirubin non-causally associates with cardiometabolic risk factors in children and adolescents.

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.

Physical Activity and Insulin Sensitivity Independently Attenuate the Effect of FTO rs9939609 on Obesity.

OBJECTIVE: The association between FTO rs9939609 and obesity is modified by physical activity (PA) and/or insulin sensitivity (IS). We aimed to assess whether these modifications are independent, to assess whether PA and/or IS modify the association between rs9939609 and cardiometabolic traits, and to elucidate underlying mechanisms. RESEARCH DESIGN AND METHODS: Genetic association analyses comprised up to 19,585 individuals. PA was self-reported, and IS was defined based on inverted HOMA insulin resistance index. Functional analyses were performed in muscle biopsies from 140 men and in cultured muscle cells. RESULTS: The BMI-increasing effect of the FTO rs9939609 A allele was attenuated by 47% with high PA (ß [SE], -0.32 [0.10] kg/m2, P = 0.0013) and by 51% with high IS (-0.31 [0.09] kg/m2, P = 0.00028). Interestingly, these interactions were essentially independent (PA, -0.20 [0.09] kg/m2, P = 0.023; IS, -0.28 [0.09] kg/m2, P = 0.0011). The rs9939609 A allele was also associated with higher all-cause mortality and certain cardiometabolic outcomes (hazard ratio, 1.07-1.20, P > 0.04), and these effects tended to be weakened by greater PA and IS. Moreover, the rs9939609 A allele was associated with higher expression of FTO in skeletal muscle tissue (0.03 [0.01], P = 0.011), and in skeletal muscle cells, we identified a physical interaction between the FTO promoter and an enhancer region encompassing rs9939609. CONCLUSIONS: Greater PA and IS independently reduced the effect of rs9939609 on obesity. These effects might be mediated through altered expression of FTO in skeletal muscle. Our results indicated that PA and/or other means of increasing insulin sensitivity could counteract FTO-related genetic predisposition to obesity.

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).

Maternal Intake of Probiotics to Program Offspring Health.

PURPOSE OF REVIEW: Probiotics intake may be considered beneficial by prospective and pregnant mothers, but their effects on offspring development are incompletely understood. The purpose of this review was to examine recent pre-clinical and clinical studies to understand how maternal probiotics exposure affects offspring health outcomes. RECENT FINDINGS: Effects were investigated in the context of supporting offspring growth, intestinal health, and gut microbiota, preventing allergic diseases, supporting neurodevelopment, and preventing metabolic disorders in pre-clinical and clinical studies. Most human studies focused on infancy outcomes, whereas pre-clinical studies also examined outcomes at adolescence and young adulthood. While still understudied, both pre-clinical and clinical studies propose epigenetic modifications as an underlying mechanism. Optimal timing of intervention remains unclear. Administration of selected probiotics to mothers has programming potential for sustaining life-long health of offspring. Administration protocols, specific windows of susceptibility, and individual-specific responses need to be further studied.

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 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.

Genome-wide association study of circulating levels of glucagon during an oral glucose tolerance test.

BACKGROUND: In order to explore the pathophysiology underlying type 2 diabetes we examined the impact of gene variants associated with type 2 diabetes on circulating levels of glucagon during an oral glucose tolerance test (OGTT). Furthermore, we performed a genome-wide association study (GWAS) aiming to identify novel genomic loci affecting plasma glucagon levels. METHODS: Plasma levels of glucagon were examined in samples obtained at three time points during an OGTT; 0, 30 and 120 min, in two separate cohorts with a total of up to 1899 individuals. Cross-sectional analyses were performed separately in the two cohorts and the results were combined in a meta-analysis. RESULTS: A known type 2 diabetes variant in EYA2 was significantly associated with higher plasma glucagon level at 30 min during the OGTT (Beta 0.145, SE 0.038, P = 1.2 × 10-4) corresponding to a 7.4% increase in plasma glucagon level per effect allele. In the GWAS, we identified a marker in the MARCH1 locus, which was genome-wide significantly associated with reduced suppression of glucagon during the first 30 min of the OGTT (Beta - 0.210, SE 0.037, P = 1.9 × 10-8), equivalent to 8.2% less suppression per effect allele. Nine additional independent markers, not previously associated with type 2 diabetes, showed suggestive associations with reduced glucagon suppression during the first 30 min of the OGTT (P < 1.0 × 10-5). CONCLUSIONS: A type 2 diabetes risk variant in the EYA2 locus was associated with higher plasma glucagon levels at 30 min. Ten additional variants were suggestively associated with reduced glucagon suppression without conferring increased type 2 diabetes risk.

Differential pattern of Doppler signals at lower-extremity entheses of healthy children.

BACKGROUND: Ultrasonography might be an important imaging method for assessing the pediatric enthesis. To diagnose pathology, knowledge of physiological findings is essential but limited. OBJECTIVE: To provide a detailed ultrasonographic assessment of four lower-extremity entheses in healthy adolescents as a reference for the correct interpretation of findings in children with rheumatic diseases. MATERIALS AND METHODS: The quadriceps tendon, proximal and distal patella tendon, and Achilles enthesis were examined in B-mode, Power and color Doppler in 41 boys and girls ages 11-14 years in neutral position and 30° flexion. We assessed Doppler signals at various distances from the enthesis and analyzed the data using a marginal logistic regression model with generalized estimating equation. We assessed agreement between observers using weighted kappa and we determined agreement on repeat scans using prevalence- and bias-adjusted kappa. RESULTS: Doppler signals were predominantly in the quadriceps and distal patella tendon with odds ratios of 50.85 and 21.35 (P<0.001) compared to the Achilles tendon. They were within 2 mm or 5 mm of the enthesis (odds ratios [ORs] of 4.58 and 4.24, P<0.001), without significant difference between flexion and neutral position and between the right and the left legs. Agreement between first and second assessment was good, with aggregate kappas from 0.79 to 0.90. The inter-reader agreement was also good, with aggregate kappas ranging from 0.75 to 0.95. CONCLUSION: We found a differential Doppler pattern in lower-extremity entheses, with signals present mostly in the quadriceps and distal patella entheses.