Girls at five are intrinsically more insulin resistant than boys: The Programming Hypotheses Revisited--The EarlyBird Study (EarlyBird 6)

Gender-related differences in cardiometabolic risk factors and oxidative stress among prepubertal children with obesity

OBJECTIVES

Gender-related differences in oxidative stress, nitric oxide bioavailability, and cardiometabolic risk factors were examined in a cross-sectional study involving 313 prepubertal children (8-9 years old) from the generation XXI birth-cohort.

METHODS

Anthropometric measurements, cardiometabolic variables, and redox markers were assessed, including plasma and urinary isoprostanes (P-Isop, U-Isop), plasma total antioxidant status (P-TAS), serum myeloperoxidase (MPO), plasma and urinary nitrates and nitrites (P-NOX, U-NOX), and urinary hydrogen peroxide (U-H2O2).

RESULTS

Girls showed higher levels of total/non-HDL cholesterol, triglycerides, and insulin resistance (HOMA-IR) compared to boys. Notably, U-H2O2 values were lower in girls. When stratifying by body mass index (BMI) and gender, both girls and boys exhibited higher MPO concentration and U-Isop values. Uric acid concentration was higher in overweight and obese girls than in normal weight girls, while no significant differences were observed among boys across BMI categories. Furthermore, U-NOX values differed only in boys, with higher levels observed in overweight and obese individuals compared to those with normal weight. Multivariate analysis, adjusted for age and BMI z-score, demonstrated inverse associations between U-H2O2 and pulse wave velocity values, as well as between U-NOX and total or non-HDL cholesterol, exclusively in boys. In girls, a positive association between U-Isop and HOMA-IR values was observed.

CONCLUSIONS

In conclusion, gender differentially impacts oxidative stress, nitric oxide bioavailability, and cardiometabolic risk factors in prepubertal children. Prepubertal girls appear more susceptible to oxidative stress-induced metabolic dysfunction, while in boys, elevated levels of redox and nitric oxide bioavailability markers seem to provide protection against arterial stiffness and lipid homeostasis.

Do sex differences in paediatric type 1 diabetes care exist? A systematic review

AIMS/HYPOTHESIS

Sex differences are present in cardiovascular care and in outcomes among adults with type 1 diabetes mellitus, which typically commences in childhood. Whether sex influences care and outcomes in childhood is not known. This systematic review provides an overview of sex differences in children with type 1 diabetes, focusing on patient and disease characteristics, treatment, comorbidities and complications.

METHODS

Literature in MEDLINE up to 15 June 2021 was searched, using the terms diabetes mellitus, sex characteristics, sex distribution, children and/or adolescents. All primary outcome studies on children with type 1 diabetes that mentioned a sex difference in outcome were included, with the exception of qualitative studies, case reports or case series. Studies not pertaining to the regular clinical care process and on incidence or prevalence only were excluded. Articles reporting sex differences were identified and assessed on quality and risk of bias using Joanna Briggs Institute critical appraisal tools. Narrative synthesis and an adapted Harvest plot were used to summarise evidence by category.

RESULTS

A total of 8640 articles were identified, rendering 90 studies for review (n=643,217 individuals). Studies were of observational design and comprised cohort, cross-sectional and case-control studies. Most of the included studies showed a higher HbA_1c in young female children both at diagnosis (seven studies, n=22,089) and during treatment (20 out of 21 studies, n=144,613), as well as a steeper HbA_1c increase over time. Many studies observed a higher BMI (all ages, ten studies, n=89,700; adolescence, seven studies, n=33,153), a higher prevalence of being overweight or obese, and a higher prevalence of dyslipidaemia among the female sex. Hypoglycaemia and partial remission occurred more often in male participants, and ketoacidosis (at diagnosis, eight studies, n=3561) and hospitalisation was more often seen in female participants. Most of the findings showed that female participants used pump therapy more frequently (six studies, n=211,324) and needed higher insulin doses than male participants. Several comorbidities, such as thyroid disease and coeliac disease, appeared to be more common in female participants. All studies reported lower quality of life in female participants (15 studies, n=8722). Because the aim of this study was to identify sex differences, studies with neutral outcomes or minor differences may have been under-targeted. The observational designs of the included studies also limit conclusions on the causality between sex and clinical outcomes.

CONCLUSIONS/INTERPRETATION

Sex disparities were observed throughout diabetes care in children with type 1 diabetes. Several outcomes appear worse in young female children, especially during adolescence. Focus on the cause and treatment of these differences may provide opportunities for better outcomes.

REGISTRATION

This systematic review is registered in PROSPERO (CRD42020213640).

Diet and Nutrients Intakes during Infancy and Childhood in Relation to Early Puberty: A Systematic Review and Meta-Analysis

The onset of puberty has become earlier over the decades, and nutrients and diet are related to the timing of puberty onset. Hence, we aimed to investigate the association between diet or nutrients in infancy, childhood and early puberty. PubMed, Embase, and Cochrane library were searched systematically up to 15 April 2022. The pooled relative risks (RRs) or regression coefficients (beta) were estimated using the random-effect model or fixed-effect model according to the heterogeneity between studies. Twenty-two articles on diet or nutrients in childhood and six about breastfeeding in infancy were included. The prolonged breastfeeding duration in infancy could reduce the risk of early menarche (beta 0.31, 95% CI: 0.01, 0.60, p = 0.045). The high intake of yogurt was associated with a 35% reduction in the risk of earlier menarche (RR 0.65, 95% CI: 0.47, 0.89, p = 0.008). Girls with severe food insecurity experienced later menarche (RR 0.81, 95% CI: 0.67, 0.98, p = 0.027). Conversely, due to the high intake of protein, the risk of early menarche increased by 8% (RR 1.08, 95% CI: 1.01, 1.16, p = 0.016). High intake of yogurt, longer duration of breastfeeding, and food insecurity decreased the possibility of earlier menarche, while high intake of protein increased that risk. As a modifiable factor, diet and nutrients in infancy and childhood provide new insights into the future prevention of early puberty.

Breastfeeding and overweight/obesity among children and adolescents: a cross-sectional study

Background

Overweight and obesity are major public health crises among children and adolescents and contribute to a significant economic burden. We aimed to investigate the relationship between breastfeeding duration and overweight and obesity in children and adolescents in Qingdao, China in 2017.

Methods

This study conducted a survey with 10,753 students (5370 boys and 5383 girls) aged 6 to 16 years from the Shibei District of Qingdao, China in 2017. Anthropometric measurements were taken by well-trained personnel and self-completed questionnaires were used to collect data from students. A variety of statistical methods were used in this study, including univariate and multivariate analyses, as well as linear and nonlinear regression models.

Results

The prevalence of overweight and obesity was 15.45% and 19.76%, respectively. There was a significant negative correlation between breastfeeding duration and BMI in children and adolescents (β = -0.025, 95% CI: -0.033, -0.005, P < 0.01). Among boys, the BMI in children and adolescences of those who have been breastfed for more than 12 months was significantly lower than that of others whose breastfeeding duration was less than 12 months (β = -0.440, 95%CI -0.655, -0.224, P < 0.01). Breastfeeding has a particularly positive effect on the prevalence of obesity in boys aged 9 to 11 years (OR = 0.978, 95% CI: 0.958,0.999, P < 0.05).

Conclusion

Breastfeeding can significantly reduce the prevalence of overweight and obesity among children and adolescents aged 6 to 16 years. Those who were breastfed for more than 12 months had a lower risk of developing overweight and obesity, especially boys between the ages of 9 and 11.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03394-z.

Sex differences in childhood sleep and health implications

CONTEXT

Sleep is critical for optimal childhood metabolic health and neurodevelopment. However, there is limited knowledge regarding childhood sex differences in sleep, including children with neurodevelopmental disorders, and the impact of such differences on metabolic health.

OBJECTIVE

To evaluate if sex differences in childhood sleep exist and if sleep associates with metabolic health outcomes equally by sex. Using autism spectrum disorder (ASD) as a case study, we also examine sleep sex differences in children with a neurodevelopmental disorder.

METHODS

A narrative review explored the literature focussing on sex differences in childhood sleep.

RESULTS

Sex differences in sleep were not detected among pre-adolescents. However, female adolescents were more likely to report impaired sleep than males. Childhood obesity is more common in males. Shorter sleep duration may be associated with obesity in male pre-adolescents/adolescents; although findings are mixed. ASD is male-predominant; yet, there was an indication that pre-adolescent female children with ASD had more impaired sleep.

CONCLUSION

Sex differences in sleep appear to emerge in adolescence with more impaired sleep in females. This trend was also observed among pre-adolescent female children with ASD. Further research is needed on sex differences in childhood sleep and metabolic health and the underlying mechanisms driving these differences.

Early life factors and their relevance for markers of cardiometabolic risk in early adulthood

BACKGROUND AND AIMS

Early life exposures could be pertinent risk factors of cardiometabolic diseases in adulthood. We assessed the prospective associations of early life factors with markers of cardiometabolic risk among healthy German adults.

METHODS AND RESULTS

We examined 348 term-born DONALD Study participants with measurement of fasting blood at the age of 18-24 years to assess metabolic indices: fatty liver index (FLI), hepatic steatosis index (HSI), pro-inflammatory score and insulin sensitivity (HOMA2-%S). Early life factors (maternal weight in early pregnancy, maternal early pregnancy BMI, gestational weight gain (GWG), maternal age, birth weight and full breastfeeding (>17 weeks)) were assessed at enrolment of the offspring into the study. Multivariable linear regression models were used to analyze associations between early life factors and markers of cardiometabolic risk in early adulthood with adjustment for potential confounders. A higher early pregnancy BMI was related to notably higher levels of offspring FLI, HSI, pro-inflammatory score and a lower HOMA2-%S (all p < 0.0001). Similarly, a higher gestational weight gain was associated with a higher FLI (p = 0.044), HSI (p = 0.016), pro-inflammatory score (p = 0.032) and a lower HOMA2-%S among females (p = 0.034). Full breastfeeding was associated with a lower adult FLI (p = 0.037). A casual mediation analysis showed that these associations were mediated by offspring adult waist circumference (WC).

CONCLUSION

This study suggests that early pregnancy BMI, gestational weight gain, and full breastfeeding are relevant for offspring markers of cardiometabolic risk which seems to be mediated by body composition in young adulthood.

Longitudinal Associations between Intake of Fruit and Vegetables and Height Attainment from Preschool to School Entry

To examine associations between fruit and vegetable intake in young childhood and height attainment during preschool and at school entry. Data for this study was based on "The Healthy Start" primary intervention study, which included 635 obesity-prone children, (58% boys), from the greater Copenhagen area, with a mean (SD) age of 4.0 (1.1) years (age range 2-6 years) at baseline. In the current study, 553 children (57% boys) were included with information on dietary intake at baseline and height measured at baseline (preschool age), and 511 children (56.8% boys) with the height measured at school entry (~6 years old). Height was measured by trained health professionals during the intervention and by school nurses at school entry. Information on intakes of fruit and vegetables, separately and combined, was gathered with four-day dietary records reported by parents. Participants were grouped into tertiles for their intakes at baseline. Compared to boys with low consumption, those with a moderate and high intakes of fruit and vegetables (F&V) had a greater attained height at preschool of 1.3 cm (95% confidence interval (CI): 0.3; 2.3) and at school entry of 2.4 cm (95% CI: 0.8; 3.9) and 1.8 cm (95% CI: 0.2; 3.4), respectively, also after adjustment for differences in age, body mass index (BMI), and total energy intake. Additional adjustment for mid-parental height and parents' education did not alter the significant associations between moderate consumption of F&V and attained height at preschool and school entry. There was no association among girls. Our results showed that a moderate consumption of F&V was directly associated with higher attainment in height at preschool and school entry in boys. From a public health perspective, it should be prioritized to continue developing intervention programs to improve fruit and vegetable intake.

[Insulin Difference of Boys and Girls at Birth]

BACKGROUND

Different opinions exist whether girls show higher insulin levels than boys at birth. Insulin values of 863 consecutively born babies whose mothers had no screening for gestational diabetes may provide clarification.

METHOD

Cord serum, measured with a commercially available insulin assay, is therefore retrospectively analyzed for insulin differences in boys and girls.

RESULTS

Girls show higher insulin values than boys (♀6.0/♂5.2 µU/ml). Insulin-sex-difference amounts to 0.8 µU/ml [95% CI 0.3 to 1.3]; p-value 0.003. It is also found in AGA babies, in children of multiparous women, after elective caesarean section and spontaneous vaginal delivery (0.8/1.2/1.7/0.9 µU/ml; p-values 0.003/0.001/0.025/0.006). Girls of multiparous women with macrosomia (LGA/≥ 4000 g) show the highest values of insulin (13.8/13.8 µU/ml) and of insulin-sex-difference (5.5/5.6 µU/ml, p-value 0.001/0.001). This insulin difference can be seen in firstborn babies weighing less than 3640 g, but ≥ 4060 g an inverse insulin sex difference (-5.4 µU/ml; p-value 0.023) with higher insulin values in boys exists (11.3 µU/ml). Children with hyperinsulinaemia (≥20 µU/ml) (17♀, 11♂) show no insulin difference, girls weigh more than boys (154 g, p-value 0.463) and later born babies more (695 g, p-value 0.0001) than firstborns.

CONCLUSION

Higher insulin values of girls have been confirmed. An as yet unknown inverse insulin difference with higher insulin values of firstborn boys with macrosomia has been proved.

Combined resistance and aerobic exercise intervention improves fitness, insulin resistance and quality of life in survivors of childhood haemopoietic stem cell transplantation with total body irradiation

PURPOSE

To investigate the effects of a supervised combined resistance and aerobic training programme on cardiorespiratory fitness, body composition, insulin resistance and quality of life (QoL) in survivors of childhood haematopoietic stem cell transplantation (HSCT) with total body irradiation (TBI).

PARTICIPANTS

HSCT/TBI survivors (n = 20; 8 females). Mean (range) for age at study and time since HSCT/TBI was 16.7 (10.9-24.5) and 8.4 (2.3-16.0) years, respectively.

METHODS

After a 6-month run-in, participants undertook supervised 45- to 60-minute resistance and aerobic training twice weekly for 6 months, with a 6-month follow-up. The following assessments were made at 0, 6 (start of exercise programme), 12 (end of exercise programme) and 18 months: Body composition via dual energy X-ray absorptiometry, homeostatic model assessment of insulin resistance (HOMA-IR), cardiorespiratory fitness (treadmill-based peak rate of oxygen uptake (VO₂ peak) test), QoL questionnaires (36-Item Short Form Health Survey (SF-36) and Minneapolis-Manchester Quality of Life Instrument (MMQL).

RESULTS

Results expressed as mean (standard deviation) or geometric mean (range). There were significant improvements in VO₂ peak (35.7 (8.9) vs 41.7 (16.1) mL/min/kg, P = 0.05), fasted plasma insulin (16.56 (1.48-72.8) vs 12.62 (1.04-54.97) mIU/L, P = 0.03) and HOMA-IR (3.65 (0.30-17.26) vs 2.72 (0.22-12.89), P = 0.02) after the exercise intervention. There were also significant improvements in the SF-36 QoL general health domain (69.7 (14.3) vs 72.7 (16.0), P = 0.001) and the MMQL school domain (69.1 (25.2) vs (79.3 (21.6), P = 0.03) during the exercise intervention. No significant changes were observed in percentage body fat, fat mass or lean mass.

CONCLUSION

The supervised 6-month combined resistance and aerobic exercise programme significantly improved cardiorespiratory fitness, insulin resistance and QoL in childhood HSCT/TBI survivors, with no change in body composition, suggesting a metabolic training effect on muscle. These data support a role for targeted physical rehabilitation services in this group at high risk of diabetes and cardiovascular disease.

Determinants of insulin resistance in children exposed to gestational diabetes in utero

BACKGROUND

The evolution of increased adiposity and cardiometabolic risk in offspring exposed to maternal gestational diabetes (GDM) is not well understood.

OBJECTIVE

(a) To evaluate the impact of in utero exposure to GDM and maternal weight status on homeostasis model assessment of insulin resistance (HOMA-IR) in the offspring longitudinally from 1 to 3 years of age and (b) to compare body mass index (BMI) and HOMA-IR in GDM and non-GDM exposed offspring at 1 and 3 years of age.

METHODS

A prospective cohort of children born to mothers with and without GDM underwent metabolic characterization between birth and 3 years of age.

RESULTS

In the overall cohort, weight gain between birth and 3 years of age was positively associated with HOMA-IR (β = 0.1491, P = .02), independent of maternal weight status. HOMA-IR was not different between GDM and non-GDM exposed children from 1 to 3 years of age; however, BMI z score was greater in GDM exposed children at 3 years of age. Among non-GDM exposed children, male sex predicted a 35.1% lower HOMA-IR (P = .03). In GDM exposed offspring, a 1 unit increase in maternal insulin sensitivity predicted a 20.8% decrease in HOMA-IR (P = .002).

CONCLUSIONS

Overall, weight gain in the first 3 years of life was positively associated with HOMA-IR, while insulin sensitivity of mothers with GDM negatively predicted HOMA-IR in the offspring. Our findings indicate the need to target weight trajectories in early life, as well as maternal factors during gestation to improve metabolic outcomes in the offspring, particularly those exposed to GDM.

Cell Type- and Sex-Specific Dysregulation of Thyroid Hormone Receptors in Placentas in Gestational Diabetes Mellitus

Thyroid hormones are essential for development of trophoblasts and the fetus. They also regulate a wide range of metabolic processes. We investigated the influence of maternal gestational diabetes mellitus (GDM) on thyroid hormone receptor (THR) isoforms THRα1, THRα2, THRβ1 and THRβ2 of the human placenta in a sex- and cell-type specific manner. Term placental tissue was obtained from women with (n = 40) or without GDM (control; n = 40). THRs levels were measured by semi-quantitative immunohistochemistry and real-time qRT-PCR. We localized THR immunostaining in syncytiotrophoblast (SCT), which was the tissue with the strongest signal. Double immunofluorescence identified THR in decidual cells in the stroma and in extravillous cytotrophoblasts. GDM did not change THRα1 immunolabelling intensity in decidua, but was associated with a stronger immunolabelling in SCT compared to GDM (p < 0.05). The SCT difference of GDM vs. control was strongest (p < 0.01) in female placentas. THRα2 was only weakly present and immunolabelling was weaker (p < 0.05) in SCT of only male GDM placentas in comparison to male controls. THRβ1/β2 immunostaining was weak in all cell types without changes in GDM. However, more THRβ1/2 protein was present (p < 0.001) in male than female placentas. All these protein changes were paralleled by changes of THR transcript levels. The data show that THR are expressed in term trophoblast in relation to fetal sex. Maternal GDM influences predominantly THRα1 in SCT, with the strongest GDM effect in SCT of female placentas.

Association between pubertal development stages and body adiposity in children and adolescents

Background

The study aimed to analyze the association between pubertal development stages and adiposity in children and adolescents.

Methods

Cross-sectional study conducted in 2007 in Florianópolis, Brazil, with 2339 schoolchildren 32 aged 8 to 14 years old (1107 males). The outcome (adiposity) was evaluated using Z score and 33 percentilee values > = 85 of four skinfolds (triceps, subscapular, suprailiac and calf) and waist 34 circumference. Total body adiposity (Z score of the sum of skinfolds), central adiposity (Z score 35 of waist circumference) and peripheral adiposity (Z scores of triceps and calf skinfolds) were 36 estimated. Pubertal development stages was self-assessed according to Tanner stages of development. Thirty-seven Children and adolescents were classified according to tertiles of age for each pubertal development stages 38 stage - early, normal and late. Statistical analysis was performed using univariate and 39 multivariate Poisson regression models.

Results

Children and adolescent from both sexes with early pubertal development stages presented higher prevalence of central adiposity (waist circumference), with adjusted prevalence ratio (CI 95%) of 2.21 (1.12; 4.35) for males and 2.18 (1.04; 4.57) for females (reference group: normal pubertal development stages). Among females, there was a reduction in the prevalence of excess adiposity with decreased occurrence of early pubertal development stages. There was a strong relationship between adiposity and pubertal development stages.

Conclusions

Excess adiposity was higher in both sexes for those with early pubertal development stages.

Sex differences in the burden of type 2 diabetes and cardiovascular risk across the life course

By 2017 estimates, diabetes mellitus affects 425 million people globally; approximately 90-95% of these have type 2 diabetes. This narrative review highlights two domains of sex differences related to the burden of type 2 diabetes across the life span: sex differences in the prevalence and incidence of type 2 diabetes, and sex differences in the cardiovascular burden conferred by type 2 diabetes. In the presence of type 2 diabetes, the difference in the absolute rates of cardiovascular disease (CVD) between men and women lessens, albeit remaining higher in men. Large-scale observational studies suggest that type 2 diabetes confers 25-50% greater excess risk of incident CVD in women compared with men. Physiological and behavioural mechanisms that may underpin both the observed sex differences in the prevalence of type 2 diabetes and the associated cardiovascular burden are discussed in this review. Gender differences in social behavioural norms and disparities in provider-level treatment patterns are also highlighted, but not described in detail. We conclude by discussing research gaps in this area that are worthy of further investigation.

Preschool children's physical activity and cardiovascular disease risk: A systematic review

OBJECTIVES

Higher physical activity (PA) levels in adults are associated with lower cardiovascular disease risk, however it is unclear whether this association is evident in children younger than five years. Given that cardiovascular disease has early life origins, this study systematically reviews evidence of associations between PA and cardiovascular disease risk factors among children aged 3-5.5years.

DESIGN

Systematic review.

METHOD

A systematic search of multiple data bases was conducted to identify published papers reporting associations between any measure of PA and cardiovascular disease risk factors.

INCLUSION CRITERIA

English language; peer-reviewed; original quantitative research; mean age or majority of sample to be between 3.0-5.5years. Studies where the sample was characterised by a health condition (e.g. obese, hypertensive) were not eligible for inclusion.

RESULTS

Twelve papers met the inclusion criteria. At least one study for each cardiovascular disease risk factor except inflammation was included. PA was not associated with insulin resistance, and inconsistently associated with the remaining cardiovascular disease risk factors. Studies were mostly cross-sectional and methodologically heterogeneous. Longitudinal and experimental study designs and objective measurement of PA may help provide a clearer indication of the interplay between PA and cardiovascular disease risk in the preschool population.

Maternal insulin resistance, triglycerides and cord blood insulin are not determinants of offspring growth and adiposity up to 5 years: a follow-up study

AIMS

Metabolic dysregulation in utero may influence fetal metabolism and early growth. We previously investigated relationships between maternal indices of glucose homeostasis and triglycerides as well as cord blood insulin with offspring anthropometry up to 2 years. The aim of this analysis was to follow these relationships up to the age of 5 years.

METHODS

Associations between maternal metabolic variables of glucose and lipid metabolism measured at 32 weeks' gestation and cord blood insulin with growth and body composition of 162 offspring aged 3-5 years were explored. Both indirect (i.e. body weight, BMI percentiles, sum of four skinfold thicknesses) and direct (i.e. ultrasonography, magnetic resonance imaging in a subgroup) measurement techniques were employed.

RESULTS

Maternal metabolic indices were largely unrelated to child body composition. Cord blood insulin was negatively associated with fat mass and lean body mass at 3 years in unadjusted analyses, and the sum of four skinfold thicknesses and body fat percentage in adjusted analyses, whereas the association with lean body mass was no longer observed. An inverse relationship between cord blood insulin and weight gain up to 5 years was observed in girls only with small effect sizes.

CONCLUSIONS

Results from this follow-up do not provide convincing evidence that these markers are independently related to offspring growth and adiposity in early childhood. Although cord blood insulin was weakly inversely related to weight gain in girls at 5 years, we cannot conclude that the observed changes in outcomes are clinically meaningful. (Clinical Trials Registry No: NCT00362089).

Sex and gender differences in developmental programming of metabolism

BACKGROUND

The early life environment experienced by an individual in utero and during the neonatal period is a major factor in shaping later life disease risk-including susceptibility to develop obesity, diabetes, and cardiovascular disease. The incidence of metabolic disease is different between males and females. How the early life environment may underlie these sex differences is an area of active investigation.

SCOPE OF REVIEW

The purpose of this review is to summarize our current understanding of how the early life environment influences metabolic disease risk in a sex specific manner. We also discuss the possible mechanisms responsible for mediating these sexually dimorphic effects and highlight the results of recent intervention studies in animal models.

MAJOR CONCLUSIONS

Exposure to states of both under- and over-nutrition during early life predisposes both sexes to develop metabolic disease. Females seem particularly susceptible to develop increased adiposity and disrupted glucose homeostasis as a result of exposure to in utero undernutrition or high sugar environments, respectively. The male placenta is particularly vulnerable to damage by adverse nutritional states and this may underlie some of the metabolic phenotypes observed in adulthood. More studies investigating both sexes are needed to understand how changes to the early life environment impact differently on the long-term health of male and female individuals.

Metabolic Profiles in Obese Children and Adolescents with Insulin Resistance

BACKGROUND:

In the past several decades, the increasing frequency of overweight and obese children and adolescents in the world has become a public health problem. It has contributed significantly to the already high tide of diabetes, cardiovascular and cerebrovascular diseases.

AIM:

To investigate the frequency of insulin resistance and to evaluate the metabolic profile of insulin resistant and non-insulin resistant obese children and adolescents.

SUBJECTS AND METHODS:

The study included 96 (45 boys, 51 girls) obese children and adolescents aged 4-17 years old (10.50 ± 2.87 years). Only participants with Body Mass Index ≥ 95 percentile were included. We analysed sera for fasting insulin levels (FI), fasting serum triglycerides (TG), total serum cholesterol (TC), fasting plasma glucose (FPG) and plasma glucose 2 hours after the performance of the oral glucose tolerance test (2-h G). Homeostatic model assessment for insulin resistance (HOMA-IR) index was calculated as fasting insulin concentration (microunits per millilitre) x fasting glucose concentration (millimolar)/22.5. The value of HOMA-IR above 3.16 was used as a cut-off value for both genders.

RESULTS:

Insulin resistance was determined in 58.33% of study participants. Insulin resistant participants had significantly higher level of 2-h G (p = 0.02), FI level (p = 0.000) as well as TG levels (p = 0.01), compared to non-insulin resistant group. Strikingly, 70.73% of the pubertal adolescents were insulin resistant in comparison to 49.09% of the preadolescents (p = 0.03). Significantly higher percentage of insulin-resistant participants were girls (p = 0.009). Moreover, a higher percentage of the girls (70.59%) than boys (44.44%) had HOMA-IR above 3.16 and had elevated FI levels (70.59% vs 48.89%). The difference in the frequency of insulin resistance among obese versus severely obese children and adolescents was not significant (p = 0.73, p > 0.05). Our study results also showed positive, but weak, correlation of HOMA-IR with age, FPG, TG and BMI of the participants (p < 0.05).

CONCLUSION:

Higher percentage of insulin-resistant participants was of female gender and was adolescents. In general, insulin resistant obese children and adolescents tend to have a worse metabolic profile in comparison to individuals without insulin resistance. It is of note that the highest insulin resistance was also linked with the highest concentrations of triglycerides.

Insulin resistance is higher in prepubertal girls but switches to become higher in boys at age 16: A Cohort Study (EarlyBird 57)

BACKGROUND

The risk of type 2 diabetes is increasing in teenage girls, and is associated with their greater insulin resistance (IR).

HYPOTHESIS

We hypothesized that the adverse metabolic profile of girls (compared with boys) would persist from childhood through adolescence.

PATIENTS AND METHODS

Community-based longitudinal cohort of 292 children (147 boys) studied annually from 9 to 16 years.

MEASURES

IR (homeostasis-model-assessment-2), high-density lipoprotein-cholesterol (HDL-C), triglycerides, % body-fat (dual-energy x-ray absorptiometry), pubertal stage (age at peak height velocity), physical activity (accelerometry). Multi-level modelling established the age-related trends in IR and lipids and the influence of covariates.

RESULTS

Each year from 9 to 15 years, girls had 21% to 63% higher IR than boys (girls mean IR 0.73-1.33, boys 0.51-0.89, P < .005). At 16 years the gender difference was not significant (girls IR 0.60, boys 0.56, P = .45). Girls had lower HDL-C from 9 to 12 years, higher triglycerides from 9 to 14 years, greater adiposity throughout, and earlier puberty, but boys were more active than girls (all P < .05). After adjustment for %-fat, puberty and activity, the gender difference in IR between girls and boys aged 9 to 15 years became non-significant (IR girls 0.66-1.01, boys 0.65-1.04, P > .07). However, after adjustment at 16 years, girls' IR was 25% lower than boys' (girls 0.44, boys 0.63, P = .001), and they had 22% higher HDL-C (P < .001) and 20% lower triglycerides (P = .003).

CONCLUSIONS

The higher IR of prepubertal and early pubertal girls diminishes during late puberty, and boys begin to exhibit greater metabolic risk. Despite being leaner and more active, boys at 16 years have higher IR than girls, suggesting future higher risk for diabetes, thus we reject our hypothesis.

Associations among osteocalcin, leptin and metabolic health in children ages 9-13 years in the United States

Background

This study aimed to investigate the relationships among osteocalcin, leptin and metabolic health outcomes in children ages 9–13 years.

Methods

This was a cross-sectional analysis of baseline data from 161 boys and 157 girls (ages 9–13 years) who previously participated in a double-blinded randomized placebo controlled trial of vitamin D supplementation. Relationships among fasting serum total osteocalcin (tOC), undercarboxylated osteocalcin (ucOC), leptin, and metabolic health outcomes were analyzed.

Results

Approximately 52% of study participants were obese based on percent body fat cutoffs (>25% for boys and >32% for girls) and about 5% had fasting serum glucose within the prediabetic range (i.e. 100 to 125 mg/dL). Serum tOC was not correlated with leptin, glucose, insulin, HOMA-IR, or HOMA-β after adjusting for percent body fat. However, serum ucOC negatively correlated with leptin (partial r = −0.16; p = 0.04) and glucose (partial r = −0.16; p = 0.04) after adjustment for percent body fat. Leptin was a positive predictor of insulin, glucose, HOMA-IR, and HOMA-β after adjusting for age, sex and percent body fat (all p < 0.001).

Conclusions

These data depict an inverse relationship between leptin and various metabolic health outcomes in children. However, the notion that tOC or ucOC link fat with energy metabolism in healthy children was not supported.

Clinical trial registration number

NCT00931580.

Generational change in fasting glucose and insulin among children at ages 5-16y: Modelled on the EarlyBird study (2015) and UK growth standards (1990) (EarlyBird 69)

AIM

Pre-diabetes is a state of beta-cell stress caused by excess demand for insulin. Body mass is an important determinant of insulin demand, and BMI has risen substantially over recent time. We sought to model changes in the parameters of glucose control against rising BMI over the past 25years.

METHODS

Using random coefficient mixed models, we established the correlations between HbA1C, fasting glucose, fasting insulin, HOMA2-IR and BMI in contemporary (2015) children (N=307) at ages 5-16y from the EarlyBird study, and modelled their corresponding values 25years ago according to the distribution of BMI in the UK Growth Standards (1990).

RESULTS

There was little change in HbA1C or fasting glucose over the 25y period at any age or in either gender. On the other hand, the estimates for fasting insulin and HOMA2-IR were substantially higher in both genders in 2015 compared with 1990.

CONCLUSION

Insofar as it is determined by body mass, there has been a substantial rise in beta cell demand among children over the past 25years. The change could be detected by fasting insulin and HOMA2-IR, but not by fasting glucose or HbA1C.

Dose-Response Relationship between Alanine Aminotransferase Levels within the Reference Interval and Metabolic Syndrome in Chinese Adults

PURPOSE

Elevation in serum alanine aminotransferase (ALT) levels is a biomarker for metabolic syndrome (MS); however, the relationship has not been fully investigated within the reference interval of ALT levels. Our objective was to explore the relationship between serum ALT levels within the reference interval and MS in Chinese adults.

MATERIALS AND METHODS

This cross-sectional study included 16028 adults, who attended routine health check-ups at Shengli Oilfield Central Hospital from January 2006 to March 2012. The reference interval of serum ALT level was defined as less than 40 U/L. Logistic regression models and restricted cubic spline were used to evaluate the association of ALT with MS.

RESULTS

The prevalence of MS in the total population was 13.7% (6.4% for females and 18.4% for males). Multiple logistic regression showed that ALT levels were positively associated with MS after adjustment for potential confounding factors. The odds ratio of MS in the top quartile was 4.830 [95% confidence interval (CI): 2.980-7.829] in females and 3.168 (95% CI: 2.649-3.790) in males, compared with the ALT levels in the bottom quartile. The restricted cubic spline models revealed a positive non-linear dose-response relationship between ALT levels and the risk of MS in women (p for nonlinearity was 0.0327), but a positive linear dose-response relationship in men (p for nonlinearity was 0.0659).

CONCLUSION

Serum ALT levels within the reference interval are positively associated with MS in a dose-response manner. Elevated ALT levels, even within the reference interval, may reflect early dysmetabolic changes.

Growth in Total Height and Its Components and Cardiometabolic Health in Childhood

BACKGROUND

Short stature or short legs is associated with cardiometabolic disease. Few studies have addressed this issue in children, incorporated repeated measures, or studied modern cohorts.

METHODS

We examined if change in total height, leg length and trunk length between two time points from early (median: 3.2 years) to mid-childhood (median: 7.7 years), with and without adjustment for concurrent change in adiposity (subscapular plus triceps skinfold thickness), was associated with mid-childhood cardiometabolic risk in 315 boys and 295 girls from Project Viva. The main outcome was a cardiometabolic risk score based on sex-specific internal z-scores for systolic blood pressure, waist circumference, homeostatic model assessment of insulin resistance, triglycerides and high-density lipoprotein-cholesterol.

RESULTS

Mean (SD) total height was 97.9 (4.5) cm in boys and 97.1 (4.7) cm in girls in early childhood and 129.1 (7.2) cm in boys and 128.3 (7.9) cm in girls in mid-childhood. Trunk length constituted about half of total height. In linear regression models adjusted for parental anthropometry and socio-demographics, faster growth in total height, leg length and particularly trunk length, were associated with higher cardiometabolic risk in mid-childhood. Per 1 cm annual increase in trunk length, the cardiometabolic risk score was 0.23 z-score (95% confidence interval [CI] 0.08, 0.39) higher among boys and 0.47 z-score (95% CI 0.33, 0.60) higher among girls. Estimates were attenuated after adjusting for adiposity (boys: 0.03 z-score, 95% CI -0.11, 0.18; girls: 0.32 z-score, 95% CI 0.19, 0.45).

CONCLUSION

Rapid linear growth, particularly in trunk length, was associated with higher cardiometabolic risk in childhood, which was explained by relationships of linear growth with adiposity in boys, but only partly in girls.

Insulin resistance in prepubertal obese children correlates with sex-dependent early onset metabolomic alterations

Background:

Insulin resistance (IR) is usually the first metabolic alteration diagnosed in obese children and the key risk factor for development of comorbidities. The factors determining whether or not IR develops as a result of excess body mass index (BMI) are still not completely understood.

Objectives:

This study aimed to elucidate the mechanisms underpinning the predisposition toward hyperinsulinemia-related complications in obese children by using a metabolomic strategy that allows a profound interpretation of metabolic profiles potentially affected by IR.

Methods:

Serum from 60 prepubertal obese children (30 girls/30 boys, 50% IR and 50% non-IR in each group, but with similar BMIs) were analyzed by using liquid chromatography–mass spectrometry, gas chromatography–mass spectrometry and capillary electrophoresis–mass spectrometry following an untargeted metabolomics approach. Validation was then performed on a group of 100 additional children with the same characteristics.

Results:

When obese children with and without IR were compared, 47 metabolites out of 818 compounds (P<0.05) obtained after data pre-processing were found to be significantly different. Bile acids exhibit the greatest changes (that is, approximately a 90% increase in IR). The majority of metabolites differing between groups were lysophospholipids (15) and amino acids (17), indicating inflammation and central carbon metabolism as the most altered processes in impaired insulin signaling. Multivariate analysis (OPLS-DA models) showed subtle differences between groups that were magnified when females were analyzed alone.

Conclusions:

Inflammation and central carbon metabolism, together with the contribution of the gut microbiota, are the most altered processes in obese children with impaired insulin signaling in a sex-specific fashion despite their prepubertal status.

Correlation of Insulin Resistance with Anthropometric Measures and Blood Pressure in Adolescents

BACKGROUND

Blood pressure is directly related to body mass index, and individuals with increased waist circumference have higher risk of developing hypertension, insulin resistance, and other metabolic changes, since adolescence.

OBJECTIVE

to evaluate the correlation of blood pressure with insulin resistance, waist circumference and body mass index in adolescents.

METHODS

Cross-section study on a representative sample of adolescent students. One group of adolescents with altered blood pressure detected by casual blood pressure and/or home blood pressure monitoring (blood pressure > 90th percentile) and one group of normotensive adolescents were studied. Body mass index, waist circumference were measured, and fasting glucose and plasma insulin levels were determined, using the HOMA-IR index to identify insulin resistance.

RESULTS

A total of 162 adolescents (35 with normal blood pressure and 127 with altered blood pressure) were studied; 61% (n = 99) of them were boys and the mean age was 14.9 ± 1.62 years. Thirty-eight (23.5%) adolescents had altered HOMA-IR. The group with altered blood pressure had higher values of waist circumference, body mass index and HOMA-IR (p<0.05). Waist circumference was higher among boys in both groups (p<0.05) and girls with altered blood pressure had higher HOMA-IR than boys (p<0.05). There was a significant moderate correlation between body mass index and HOMA-IR in the group with altered blood pressure (ρ = 0.394; p < 0.001), and such correlation was stronger than in the normotensive group. There was also a significant moderate correlation between waist circumference and HOMA-IR in both groups (ρ = 0.345; p < 0.05). Logistic regression showed that HOMA-IR was as predictor of altered blood pressure (odds ratio - OR = 2.0; p = 0.001).

CONCLUSION

There was a significant association of insulin resistance with blood pressure and the impact of insulin resistance on blood pressure since childhood. The correlation and association between markers of cardiovascular diseases was more pronounced in adolescents with altered blood pressure, suggesting that primary prevention strategies for cardiovascular risk factors should be early implemented in childhood and adolescence.

Reference ranges of HOMA-IR in normal-weight and obese young Caucasians

AIMS

Insulin resistance (IR) may develop very early in life being associated with occurrence of cardiometabolic risk factors (CMRFs). Aim of the present study was to identify in young Caucasians normative values of IR as estimated by the homeostasis model assessment (HOMA-IR) and cutoffs diagnostic of CMRFs.

METHODS

Anthropometrics and biochemical parameters were assessed in 2753 Caucasians (age 2-17.8 years; 1204 F). Reference ranges of HOMA-IR were defined for the whole population and for samples of normal-weight and overweight/obese individuals. The receiver operator characteristic analysis was used to find cutoffs of HOMA-IR accurately identifying individuals with any CMRF among total cholesterol and/or triglycerides higher than the 95th percentile and/or HDL cholesterol lower than the 5th for age and sex, impaired glucose tolerance, and alanine aminotransferase levels ≥40 U/l.

RESULTS

Overweight/obese individuals had higher HOMA-IR levels compared with normal-weight peers (p < 0.0001) at any age. HOMA-IR index rose progressively with age, plateaued between age 13 and 15 years and started decreasing afterward. HOMA-IR peaked at age 13 years in girls and at 15 years in boys. The 75th percentile of HOMA-IR in the whole population (3.02; AUROC = 0.73, 95 % CI = 0.70-0.75), in normal-weight (1.68; AUROC = 0.76, 95 % CI = 0.74-0.79), and obese (3.42; AUROC = 0.71, 95 % CI = 0.69-0.72) individuals identified the cutoffs best classifying individuals with any CMRF.

CONCLUSIONS

Percentiles of HOMA-IR varied significantly in young Caucasians depending on sex, age, and BMI category. The 75th percentile may represent an accurate cutoff point to suspect the occurrence of one or more CMRFs among high total cholesterol and triglycerides, low HDL cholesterol, and ALT ≥ 40 UI/l.

Gender differences in insulin and C-peptide concentrations at birth using cord blood collection

OBJECTIVE

To study gender differences in insulin and C-peptide concentrations at birth using cord blood collection.

SUBJECTS AND METHODS

This study was conducted in a maternity hospital, in Jammu province of Jammu and Kashmir, India. All women with pregnancy who were hospitalized for delivery were followed. All pregnant ladies who had no medical condition affecting insulin levels, as per history and routine antenatal blood testing, were included in the study. The test for cord plasma insulin and C-peptide was done in 60 (30 males) full-term (≥ 37 completed weeks) normal delivery babies within 4 hours of the collection of samples using the electro-chemiluminescence immunoassay (ECLIA) on Roche elecsys module immunoassay analyzer. Weight of the babies was taken immediately after birth using digital scales.

RESULTS

Cord plasma insulin and C-peptide measured in EDTA were compared between boys and girls and also related to birth weight. Girls were lighter (2,830 ± 37 vs. 3,236 ± 46 g; p = < 0.001) but had higher cord insulin (16.48 ± 4.88 vs. 10.53 ± 4.04 µU/mL; p = < 0.001), and C-peptide (2.47 ± 0.66 vs. 0.834 ± 0.26 ng/mL; p = < 0.001) concentrations than newborn boys.

CONCLUSION

Female newborn babies have higher cord plasma insulin and C-peptide concentrations than male newborns, despite being smaller, suggesting intrinsic insulin resistance in girls.

The Effects of Fetal Gender on Maternal and Fetal Insulin Resistance

OBJECTIVE

Gender plays a role in the development of a number of cardiovascular and metabolic diseases and it has been suggested that females may be more insulin resistant in utero. We sought to assess the relationship between infant gender and insulin resistance in a large pregnancy cohort.

STUDY DESIGN

This is a secondary analysis of a cohort from the ROLO randomized control trial of low GI diet in pregnancy. Serum insulin, glucose and leptin were measured in early pregnancy and at 28 weeks. At delivery cord blood C-peptide and leptin were measured. A comparison of maternal factors, fetal biometry, insulin resistance and leptin was made between male and female offspring. A multivariate regression model was built to account for the possible effects of maternal BMI, birthweight and original study group assignment on findings.

RESULTS

A total of 582 women were included in this secondary analysis, of whom 304 (52.2%) gave birth to male and 278 (47.8%) gave birth to female infants. Compared to male infants at birth, female infants were significantly lighter, (3945 ± 436 vs. 4081± 549g, p<0.001), shorter in length (52.36 ± 2.3 vs. 53.05 ± 2.4cm, p<0.001) and with smaller head circumferences (35.36 ± 1.5 vs. 36.10 ± 1.1cm, p<0.001) than males. On multiple regression analysis, women pregnant with female fetuses were less insulin resistant in early pregnancy, i.e. had lower HOMA indices (B = -0.19, p = 0.01). Additionally female fetuses had higher concentrations of both cord blood leptin and C-peptide at birth when compared to male offspring (B = 0.38, p<0.001 and B = 0.31, p = 0.03 respectively).

CONCLUSION

These findings suggest gender is a risk factor for insulin resistance in-utero. Additionally, carrying a female fetus decreases the risk of insulin resistance in the mother, from as early as the first trimester.

Sex-Specific Mediating Role of Insulin Resistance and Inflammation in the Effect of Adiposity on Blood Pressure of Prepubertal Children

Objective

To evaluate the association between obesity indices and blood pressure (BP) at 4 years of age, in each sex, and to quantify to which extent this association is mediated by inflammation and insulin resistance (IR).

Materials and Methods

We studied 1250 4-year-old children selected from the population-based birth cohort Generation XXI. Associations between body mass index (BMI) z-score and waist-to-height ratio (WHtR), office BP, inflammation (high sensitivity C-reactive protein) and IR (HOMA-IR index) were assessed. Path Analysis, a modified multivariate regression approach, was applied to test causal models and quantify direct and indirect effects of predictors of systolic (SBP) and diastolic BP (DBP).

Results

SBP and DBP increased significantly with BMI and WHtR in both sexes. There was a strong direct association (explaining 74.1-93.2% of the total association) of both measures of adiposity with SBP, in both sexes. This association was additionally indirectly mediated by IR, particularly regarding WHtR (20.5% in girls and 9.4% in boys). Mediation by inflammation did not reach statistical significance in either sex. Regarding DBP, the direct effect of adiposity was strong (>95% for BMI and WHtR in boys) and the mediation by IR was much smaller in boys than in girls.

Discussion

The direct association between adiposity and BP in healthy 4-year-old children is strong and IR plays an important mediating role. The strength of effects of IR and inflammation suggests sex differences in the complex interplay between BP, adiposity and inflammation.

Fibroblast growth factor-21, body composition, and insulin resistance in pre-pubertal and early pubertal males and females

OBJECTIVE

Accumulating evidence derived primarily from animal models suggests that fibroblast growth factor-21 (FGF-21) may affect the musculoskeletal system via effects on the capacity of tissues to respond to insulin. A proportion of musculoskeletal properties and underpinnings of promoting/preventing insulin resistance are established early in the pubertal transition. Thus, the objective of this study was to test the hypothesis that insulin resistance and/or obesity will promote greater FGF-21 concentration which will be inversely associated with musculoskeletal parameters [lean mass and bone mineral content (BMC)] in pre-/early pubertal children. Given the sexual dimorphic nature of musculoskeletal development of fat mass accrual, differences by obesity status and sex were also investigated.

DESIGN

Cross-sectional.

PATIENTS

Children ages 7-12 years (n = 69, 38% male, 48% non-Hispanic black, 45% obese).

MEASUREMENTS

Fasting FGF-21, glucose and insulin measures were obtained. An estimate of insulin resistance was derived using the homoeostatic model assessment of insulin resistance (HOMA-IR). Body composition (BMC, lean mass and fat mass) was assessed by DXA. Multivariate regression analysis was used to evaluate the influence of FGF-21 on BMC, lean mass and HOMA-IR as dependent variables. Obesity status was established based on BMI z-score.

RESULTS

FGF-21 concentrations did not differ by obesity status or by sex. There was an inverse association between FGF-21 and BMC among nonobese individuals (P = 0·01) and an inverse association between FGF-21 and lean mass among females (P = 0·02), which were both independent of fat mass. FGF-21 was inversely associated with HOMA-IR in males, but not females (P = 0·04).

CONCLUSIONS

The existence of relationships of FGF-21 with musculoskeletal parameters and insulin resistance raises the possibility of crosstalk between these systems. These findings suggest that circulating FGF-21 may differ in its association with bone, lean mass and insulin resistance depending on sex and weight status.

Interaction between paraoxonase 1 polymorphism and prenatal pesticide exposure on metabolic markers in children using a multiplex approach

Prenatal environmental exposures may influence the risk of cardio-metabolic diseases later in life. This study used a multiplex approach to investigate non-fasting serum levels of metabolic markers in a cohort of school-aged children for whom associations between prenatal pesticide exposure and body fat content and blood pressure were previously found to be dependent on paraoxonase1 (PON1) Q192R genotype. In children with the PON1 192 R-allele, leptin, glucagon, and plasminogen activator inhibitor-1 (PAI-1) were positively associated with prenatal pesticide exposure. For PON1 192 QQ-homozygote children none of the biomarkers were significantly affected by prenatal pesticide exposure. In children with the R-allele, leptin was associated with both body fat measures and prenatal pesticide exposure and seems to mediate body fat accumulation in exposed children. These findings support our previous results of an adverse cardio-metabolic risk profile associated with prenatal pesticide exposure in children with the PON1 192 R-allele.

Plasma insulin levels in childhood are related to maternal factors--results of the Ulm Birth Cohort Study

AIMS

The cardiovascular risk factor profile of a child as well as the development of body weight are influenced by genetic and childhood factors. Circulating insulin concentrations reflect the metabolic cardiovascular risk and may trigger weight gain. We aimed at identifying parental and childhood factors which may influence fasting plasma insulin concentrations in children.

METHODS

The Ulm Birth Cohort study (UBCS) is a prospective birth cohort study. At baseline, birth characteristics, maternal pre-pregnancy body mass index (BMI) values as well as parental socioeconomic parameters were obtained. At the 8-yr follow-up examination, weights, heights, and fasting plasma insulin concentrations in n = 422 children and their parents were measured. Offspring of women with gestational diabetes mellitus were excluded from statistical analysis.

RESULTS

Fasting plasma insulin concentrations of children were significantly correlated with maternal pre-pregnancy BMI values (r = 0.16) as well as with maternal (r = 0.26) but not with paternal fasting plasma insulin concentrations (r = 0.11) at the 8-yr follow-up examination. The risk for high fasting plasma insulin concentrations (≥75th internal percentile) was 2.30 (1.34-3.92) in children who also had high plasma insulin concentrations in umbilical cord blood compared to children having lower plasma insulin concentrations (<75th internal percentile) in umbilical cord blood. In addition, we observed that children with high fasting plasma insulin concentrations at the age of 8 had an altered BMI trajectory in childhood, characterized by higher BMI values from the age of 1 onwards, compared to children with lower insulin concentrations.

CONCLUSION

Our observations support the hypothesis of perinatal programming of offspring insulin concentrations and BMI values by maternal pre-pregnancy BMI values.

Predictors of increasing BMI during the course of diabetes in children and adolescents with type 1 diabetes: data from the German/Austrian DPV multicentre survey

OBJECTIVE

Increased weight gain has been reported prior to disease onset (accelerator hypothesis) and as a side effect of intensified insulin therapy in type 1 diabetes (T1D). Paediatric studies are complicated by the age-dependency and gender-dependency of BMI, and also by a trend towards obesity in the general population. The aim of this study was to evaluate factors related to the increase in BMI during the course of diabetes in children and adolescents with T1D in a large multicentre survey.

DESIGN

Within the DPV database (Diabetespatienten Verlaufsdokumentation) a standardised, prospective, computer-based documentation programme, data of 53,108 patients with T1D, aged <20 years, were recorded in 248 centres. 12,774 patients (53% male, mean age 13.4±3.9, mean diabetes duration 4.7±3.0 years and mean age at diabetes onset 8.7±4.0 years) were included in this analysis. Population-based German reference data were used to calculate BMI-SDS and define overweight and obesity.

RESULTS

12.5% of T1D patients were overweight and 2.8% were obese. Multiple longitudinal regression analysis revealed that female gender, low BMI at diabetes onset, intensified insulin therapy and higher insulin dose, as well as pubertal diabetes onset, long diabetes duration and onset in earlier calendar years among girls, were related to higher BMI-SDS increase during the course of diabetes (p<0.01; all).

CONCLUSIONS

Intensified insulin regimen is associated with weight gain during T1D treatment, in addition to demographic variables. Optimisation of diabetes management, especially in females, might limit weight gain in order to reduce overweight and obesity together with comorbidities among paediatric T1D patients.

Latent protective effects of breastfeeding on late childhood overweight and obesity: a nationwide prospective study

OBJECTIVE

To investigate the latent effect of breastfeeding on overweight and obesity in late childhood.

METHODS

Data on breastfeeding and child anthropometric measurements were collected annually from a nation-wide population-based prospective cohort study in Japan (21,425 boys and 20,147 girls). Breastfeeding status (exclusiveness and duration) was assessed when the child was 6 months old. Mixed effects models were used to evaluate trajectories of body mass index (BMI), together with overweight and obesity status, from 1.5 to 8 years of age.

RESULTS

Mixed-fed boys and exclusively breastfed boys showed lower BMI as the main effect, as well as a slower increase of inclination in BMI as interaction term between feeding type and age, than exclusively formula-fed boys. Breastfed boys had lower BMI at the ages of 7 and 8, in comparison with exclusively formula fed boys (P = 0.002 and P < 0.001, respectively). A similar association was found for girls, although the main effect of feeding type was not statistically significant. The analysis of breastfeeding duration had similar results.

CONCLUSIONS

Breastfeeding, even if partial or for short duration, has a latent protective effect against overweight and obesity in late childhood, especially for boys.

Metabolic risk in contemporary children is unrelated to socio-economic status: longitudinal study of a UK urban population (EarlyBird 42)

Lifestyle interventions to improve health in young children tend to target areas of relative deprivation, but the evidence for so doing is largely historical. Accordingly, we have re-examined the link between deprivation, obesity and metabolic risk in contemporary UK children. Using a postcode-based index of multiple deprivation (IMD), we assessed 269 children from the community-based EarlyBird Study, attending 53 schools representing a wide socio-economic range. Annual measures of fatness from 5 to 8 yr included body mass index (BMI), waist circumference (WC), and sum of five skinfolds (SSF). A metabolic risk score, based on blood pressure, lipids and insulin resistance, was derived from annual fasting blood samples. There were no significant associations between deprivation and any measure of adiposity in girls (all p > 0.37). In boys, there was a weak but consistently inverse relationship between deprivation and WC (r = -0.19, p = 0.03) and BMI (r = -0.14, p = 0.09) at 8 yr. Changes in adiposity over 3 yr were unrelated to deprivation in boys. In girls there was a slight but significant increase in SSF only (1 mm/yr per 20 IMD units, p = 0.001). Importantly, in both genders, metabolic risk score was unrelated to deprivation throughout (r values -0.05 to -0.13, all p > 0.12), as was change in metabolic risk (all p > 0.30). Our data do not support the assumption that obesity, metabolic disturbance and thus risk of type 2 diabetes are more prevalent among poorer children. In today's increasingly obesogenic environment, youngsters from all backgrounds appear to be vulnerable, with population-wide implications for public health spending, and the prevention of diabetes in contemporary youth.

Being macrosomic at birth is an independent predictor of overweight in children: results from the IDEFICS study

Fetal macrosomia is a risk factor for the development of obesity late in childhood. We retrospectively evaluated the relationship between maternal conditions associated with fetal macrosomia and actual overweight/obesity in the European cohort of children participating in the IDEFICS study. Anthropometric variables, blood pressure and plasma lipids and glucose were measured. Socio-demographic data, medical history and perinatal factors, familiar and gestational history, maternal and/or gestational diabetes were assessed by a questionnaire. Variables of interest were reported for 10,468 children (M/F = 5,294/5,174; age 6.0 ± 1.8 years, M ± SD). The sample was divided in four groups according to child birth weight (BW) and maternal diabetes: (1) adequate for gestational age offspring (BW between the 10th and 90th percentiles for gestational age) of mothers without diabetes (AGA-ND); (2) adequate for gestational age offspring of mothers with diabetes (AGA-D); (3) macrosomic offspring (BW > 90th percentile for gestational age) of mothers without diabetes (Macro-ND); (4) macrosomic offspring of mothers with diabetes (Macro-D). Children macrosomic at birth showed significantly higher actual values of body mass index, waist circumference, and sum of skinfold thickness. In both boys and girls, Macro-ND was an independent determinant of overweight/obesity, after the adjustment for confounders [Boys: OR = 1.7 95 % CI (1.3;2.2); Girls: OR = 1.6 95 % CI (1.3;2.0)], while Macro-D showed a significant association only in girls [OR = 2.6 95 % CI (1.1;6.4)]. Fetal macrosomia, also in the absence of maternal/gestational diabetes, is independently associated with the development of overweight/obesity during childhood. Improving the understanding of fetal programming will contribute to the early prevention of childhood overweight/obesity.

Changes in weight and BMI following the diagnosis of type 1 diabetes in children and adolescents

The aim of this study was to study weight and body mass index (BMI) before, at, and after diagnosis of type 1 diabetes (T1D) and to identify factors associated with weight gain. Studied retrospectively were 209 children <18 years with T1D followed for 6 years. Data collected included clinical and laboratory data before diagnosis, at diagnosis, and during 6 years of follow-up. Anthropometric parameters of patients were compared along follow-up and with those of their parents and siblings. Mean BMI-standard deviation score (SDS) was below average at diagnosis (-0.66 ± 1.27), had increased to 0.37 ± 0.93 at 3 months, and decreased to a nadir at 6 months in females and 12 months in males; between 1 and 3 years, there was a slight increase and between 3 and 6 years a further increase only in the females. BMI-SDS at 6 years was significantly higher than pre-diabetes BMI-SDS (0.35 ± 0.83 vs. -0.04 ± 1.23, p < 0.001). Patients' BMI-SDS at 6 years was similar to that of their parents and siblings, was higher in the females (0.53 ± 0.74 vs. 0.27 ± 0.82, p = 0.02) and in those keeping diabetes a secret (0.66 ± 0.82 vs. 0.33 ± 0.78, p = 0.027), and was not associated with age or pubertal stage at diagnosis, ethnicity, or metabolic control. A longer duration of insulin pump therapy was associated with a lower BMI-SDS (r = -0.2375, p < 0.025). BMI-SDS increased during the 6 years following diagnosis of T1D in pediatric patients, especially in the females, but remained in the normal range and was similar to that of other family members.

Elevated alanine aminotransferase is strongly associated with incident metabolic syndrome: a meta-analysis of prospective studies

BACKGROUND

The incidence of metabolic syndrome (MetS) is rapidly increasing worldwide and associated with alanine aminotransferase (ALT) activity. However, the impact of ALT activity on MetS incidence is inconsistent in published literature. We therefore estimated the association between elevated ALT activity and incident MetS through a meta-analysis of prospective cohort studies.

METHODS/PRINCIPAL FINDINGS

All published prospective cohort studies on the association between elevated ALT activity and incident MetS were retrieved from Pubmed, Embase, and the Institute for Scientific Information (ISI). In all, seven prospective cohort studies, with 31545 participants and 2873 cases of incident MetS were recruited. If there was insignificant heterogeneity (P-value>0.05 and I(2)<50%), the fixed-effect model was used to calculate the pooled relative risks (RRs) of incident MetS induced by raised ALT. Otherwise, the random-effect model was used. The calculated RR was 1.81 (95% confidence interval [CI]: 1.49-2.14) when the incidence of MetS was compared between the highest versus the lowest classification of ALT activities. The pooled RR was 1.13 (95% CI: 1.11-1.16) in dose-response analysis with 5 units per liter (U/l) of ALT increment. Subgroup analysis suggested that gender disparity might be the main origin of heterogeneity in overall analysis (P = 0.007 between RRs of gender-specific subgroups evaluated with 5 U/l increments of ALT). Women had a higher dose-response risk of MetS incidence (1.38, 95% CI: 1.20-1.55) than men. Furthermore, sensitivity analysis confirmed the stability of results. No publication bias was found in our meta-analysis.

CONCLUSIONS/SIGNIFICANCE

Current evidence from prospective studies supports the association between ALT elevation and increasing MetS incidence. This association is closer and more consistent in female population. Further studies are needed to confirm this association and to investigate the potential mechanism of ALT activity on MetS occurrence.

Maternal insulin resistance, triglycerides and cord blood insulin in relation to post-natal weight trajectories and body composition in the offspring up to 2 years

AIMS

The intrauterine metabolic environment might have a programming effect on offspring body composition. We aimed to explore associations of maternal variables of glucose and lipid metabolism during pregnancy, as well as cord blood insulin, with infant growth and body composition up to 2 years post-partum.

METHODS

Data of pregnant women and their infants came from a randomized controlled trial designed to investigate the impact of nutritional fatty acids on adipose tissue development in the offspring. Of the 208 pregnant women enrolled, 118 infants were examined at 2 years. In the present analysis, maternal fasting plasma insulin, homeostasis model assessment of insulin resistance and serum triglycerides measured during pregnancy, as well as insulin in umbilical cord plasma, were related to infant growth and body composition assessed by skinfold thickness measurements and abdominal ultrasonography up to 2 years of age.

RESULTS

Maternal homeostasis model assessment of insulin resistance at the 32nd week of gestation was significantly inversely associated with infant lean body mass at birth, whereas the change in serum triglycerides during pregnancy was positively associated with ponderal index at 4 months, but not at later time points. Cord plasma insulin correlated positively with birthweight and neonatal fat mass and was inversely associated with body weight gain up to 2 years after multiple adjustments. Subsequent stratification by gender revealed that this relationship with weight gain was stronger, and significant only in girls.

CONCLUSIONS

Cord blood insulin is inversely associated with subsequent infant weight gain up to 2 years and this seems to be more pronounced in girls.

Breastfeeding and its prospective association with components of the GH-IGF-Axis, insulin resistance and body adiposity measures in young adulthood--insights from linear and quantile regression analysis

BACKGROUND

Breastfeeding may lower chronic disease risk by long-term effects on hormonal status and adiposity, but the relations remain uncertain.

OBJECTIVE

To prospectively investigate the association of breastfeeding with the growth hormone- (GH) insulin-like growth factor- (IGF) axis, insulin sensitivity, body composition and body fat distribution in younger adulthood (18-37 years).

DESIGN

Data from 233 (54% female) participants of a German cohort, the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study, with prospective data on infant feeding were analyzed. Multivariable linear as well as quantile regression were performed with full breastfeeding (not: ≤ 2, short: 3-17, long: >17 weeks) as exposure and adult IGF-I, IGF binding proteins (IGFBP) -1, -2, -3, homeostasis model assessment of insulin resistance (HOMA-IR), fat mass index, fat-free mass index, and waist circumference as outcomes.

RESULTS

After adjustment for early life and socio-economic factors, women who had been breastfed longer displayed higher adult IGFBP-2 (p(trend) = 0.02) and lower values of HOMA-IR (p(trend) = 0.004). Furthermore, in women breastfeeding duration was associated with a lower mean fat mass index (p(trend) = 0.01), fat-free mass index (p(trend) = 0.02) and waist circumference (p(trend) = 0.004) in young adulthood. However, there was no relation to IGF-I, IGFBP-1 and IGFBP-3 (all p(trend) > 0.05). Associations for IGFBP-2 and fat mass index were more pronounced at higher, for waist circumference at very low or high percentiles of the distribution. In men, there was no consistent relation of breastfeeding with any outcome.

CONCLUSIONS

Our data suggest that breastfeeding may have long-term, favorable effects on extremes of adiposity and insulin metabolism in women, but not in men. In both sexes, breastfeeding does not seem to induce programming of the GH-IGF-axis.

Temporal relationship between insulin sensitivity and the pubertal decline in physical activity in peripubertal Hispanic and African American females

OBJECTIVE

Little attention has been paid to possible intrinsic biological mechanisms for the decline in physical activity that occurs during puberty. This longitudinal observational study examined the association between baseline insulin sensitivity (SI) and declines in physical activity and increases in sedentary behavior in peripubertal minority females over a year.

RESEARCH DESIGN AND METHODS

Participants were Hispanic and African American girls (n = 55; 76% Hispanic; mean age 9.4 years; 36% obese). SI and other insulin indices were measured at baseline using the frequently sampled intravenous glucose tolerance test. Physical activity was measured on a quarterly basis by accelerometry and self-report.

RESULTS

Physical activity declined by 25% and time spent in sedentary behaviors increased by ∼13% over 1 year. Lower baseline SI predicted the decline in physical activity measured by accelerometry, whereas higher baseline acute insulin response to glucose predicted the decline in physical activity measured by self-report. Time spent in sedentary behavior increased by ~13% over 1 year, and this was predicted by lower baseline SI. All models controlled for adiposity, age, pubertal stage, and ethnicity.

CONCLUSIONS

When evaluated using a longitudinal design with strong outcome measures, this study suggests that lower baseline SI predicts a greater decline in physical activity in peripubertal minority females.

Low birth weight is associated with high waist-to-height ratio in Japanese elementary school girls

In Japan, the rate of low birth weight infants has increased, due to an increase in the number of women who smoke or are lean. A recent study showed that low birth weight was associated with a high adult waist-to-height ratio in adult Japanese women, but little data is available concerning children. In this cross-sectional study with 568 subjects (276 boys and 292 girls), we examined the association between birth weight and waist-to-height ratio in 7- or 8-year-old Japanese children, all born at full term. The mothers of the subjects responded to a questionnaire about the weight of the children at birth, and physical data were collected from the results of measurements conducted at each school. We divided the subjects into two groups by the median of the birth weight (3,000 g) by sex to elucidate the effects of birth weight on the waist-to-height ratio. There were 119 boys and 164 girls and 157 boys and 128 girls in the < 3,000 g and ≥ 3,000 g birth weight groups, respectively. The Mann-Whitney U test was used to compare the physical conditions in the two birth weight categories. Height was significantly lower in the birth weight < 3,000 g group among both the boys (P < 0.001) and girls (P < 0.001). The waist-to-height ratio was significantly higher in the < 3,000 g group in girls (P = 0.004), but not in the boys. Our results suggest that intrauterine environmental insults might have an effect on children, depending on sex.

The effects of resistance exercise training on body composition and strength in obese prepubertal children

OBJECTIVE

To assess the effects of resistance exercise training on body composition and muscular strength in obese prepubertal children.

DESIGN

Study participants, who were between the ages of 8 and 12 years, met Tanner I (stage) criteria, had a body mass index ≥ 95th percentile for age and sex, were randomized to either high-repetition, moderate-intensity resistance training (n = 12) or to the non-intervention control group (n = 7) for 12 weeks. Exercise training was performed twice a week for 75 minutes per session. Body composition was assessed using dual energy x-ray absorptiometry and muscular strength was evaluated using a 1-repetition-maximum test.

RESULTS

Exercise-group participants attended 98% of the 24 total sessions and showed a significant increase in body weight (57.6± 13.5 vs 59.6± 14.1 kg), height (144.9± 9 vs 146.6± 10.4 cm), lean body mass (32.6± 6.8 vs 34.0± 7.0 kg), lean body mass index (lean body mass in kg/height2; 15.3± 1.6 vs 15.6± 1.5 kg/m2), arm strength (28.4± 5.8 vs 31.2± 6.0 kg), and leg strength (89.4± 31.7 vs 113.4± 34 2 kg) from baseline measures (P < 0.05). Control group participants also showed significant increases in weight, height, and lean body mass from baseline measures (P < 0.05) but not in arm or leg strength. When the changes in participant body composition and muscular strength were compared between the exercise and control groups, significant differences were found in leg lean mass and leg strength (P < 0.05). There were no changes in percent body fat and fat mass index [FM/height2(kg/m2)] in either group.

CONCLUSION

Resistance training increases leg lean mass and leg strength in obese prepubertal youth and may have a positive effect on overall physical activity and health.

Prevalence of metabolic syndrome among urban Indian adolescents and its relation with insulin resistance (HOMA-IR)

AIM

To assess prevalence of metabolic syndrome (MS) in urban Indian adolescents. MS in adolescents is a forerunner of diabetes mellitus and cardiovascular disease in adults, therefore, its identification provides an opportunity to intervene with lifestyle changes to prevent disease progression into adulthood. We randomly selected 900 adolescents (300 for each group) to participate in the study from a total of 15,101 adolescents (10-18 years) who were grouped as normal, overweight, and obese (total population).

METHODS

From the 900 adolescents, 695 consented to participate in the study and underwent a detailed anthropometric and biochemical evaluation, therefore, these adolescents constituted the study population. MS was defined by criteria proposed by the International Diabetes Federation (MS-IDF) and the Adult Treatment Panel (MS-ATP). The prevalence of MS in the study population was used to calculate the prevalence of MS in the total population based on the distribution of the different BMI categories in this larger sample (n=15,101).

RESULTS

Calculated prevalence of MS in urban Indian adolescents was 4.3% and 3.0% in the total population using MS-ATP and MS-IDF criteria, respectively. Among the study population, MS was higher in girls than boys (MS-ATP, G: 22.3% vs. B: 16.6%, p=0.03; MS-IDF, G: 20.5% vs. B: 13.5%, p=0.006). The most common component of MS- ATP and MS-IDF was central obesity (89.8% vs. 100.0%, p<0.00001), followed by hypertriglyceridemia (83.0% vs. 82.2%, p=0.35), low high density lipoprotein-cholesterol (71.1% vs. 71.2%, p=0.48), hypertension (44.4% vs. 44.9%, p=0.025), and dysglycemia (40.0% vs. 34.7%, p=0.94). The mean serum insulin levels and HOMA-IR progressively increased with the increasing number of components present in an individual.

CONCLUSIONS

Metabolic syndrome is common in urban Indian overweight and obese adolescents.

The effect of beverages varying in glycaemic load on postprandial glucose responses, appetite and cognition in 10-12-year-old school children

Reducing glycaemic index (GI) and glycaemic load (GL) inconsistently improves aspects of cognitive function and appetite in children. Whether altering the GL by lowering carbohydrate relative to protein and fat has a role in these effects is unknown. Therefore, we assessed the differential effects of beverages varying in GL and dairy composition on appetite, energy intake and cognitive function in children. A total of forty children (10–12 years) completed a double-blind, randomised, crossover trial, receiving three isoenergetic drinks (approximately 1100 kJ): a glucose beverage (GI 100, GL 65), a full milk beverage (GI 27, GL 5) and a half milk/glucose beverage (GI 84, GL 35). For 3 h post-consumption, subjective appetite and cognitive performance (speed of processing, memory, attention and perceptual speed) were measured hourly. At completion, each child was provided a buffet-style lunch and energy intake was calculated. Blood glucose was objectively measured using the Continuous Glucose Monitoring System. Blood glucose AUC values were significantly different between the drinks (P,0·001), but did not sustain above the baseline for 3 h for any drink. Mixed modelling revealed no effect of beverage on subjective appetite or energy intake. Participant sex and drink GL significantly interacted for short-term memory (P,0·001). When girls consumed either milk-containing beverage, they recalled 0·7–0·8 more words compared with 0·5 less words after the glucose drink (P#0·014). Altering GL of drinks by reducing carbohydrate and increasing protein did not affect appetite or cognition in children. Girls may demonstrate improved short-term memory after consuming beverages with higher protein and lower GL.

Evaluation of metabolic risk in prepubertal girls versus boys in relation to fitness and physical activity

BACKGROUND

Low levels of cardiorespiratory fitness (CRF) and physical activity (PA) are associated with a risk of the development of metabolic syndrome. Contradictory findings are reported in the literature regarding the influence of sex and CRF and PA on metabolic changes.

OBJECTIVE

The aim of this study was to analyze the effects of CRF and PA on lipid and carbohydrate metabolism biomarkers in boys and girls.

METHODS

A total of 82 prepubertal boys and 55 girls (7-12 years of age) were classified according to sex, low or high CRF, and performance or nonperformance of PA. Anthropometric and blood pressure (BP) measurements, plasma lipid profile values, glucose and insulin levels, and homeostasis model assessment for insulin resistance were analyzed.

RESULTS

The percentage of boys with high CRF and performance of PA was higher than that of girls (P < 0.05). When children of the same sex were compared, higher values for body mass index and waist circumference z-scores were found for boys with low CRF compared with boys with high CRF (P < 0.001) without differences between girls, and in all groups classified by PA. Systolic and diastolic BPs were higher in boys than in girls, in both CRF and PA groups (P < 0.05). In the low CRF and no PA groups, girls had higher plasma glucose, total cholesterol, and low-density lipoprotein cholesterol levels than boys, with higher high-density lipoprotein cholesterol and apolipoprotein A levels (P < 0.05).

CONCLUSIONS

Sex in relation to CRF and PA could affect the plasma lipid profile. These changes in girls are associated with low CRF and low levels of PA. Considering these results, we suggest the need to improve CRF and promote PA, especially in girls, to reduce metabolic risk.

Association between low birth weight and high adult waist-to-height ratio in non-obese women: a cross-sectional study in a Japanese population

Low birth weight has been associated with cardiovascular diseases. The waist-to-height ratio is a good indicator of risks for these diseases. The objective of this study was to examine the associations between birth weight and adult waist-to-height ratio in a Japanese population. A cross-sectional study, comprised of 851 subjects (401 men and 450 women) aged 35-62 years who were born at full term, was conducted at a medical checkup. The subjects responded to a questionnaire about weight at birth, and data on physical characteristics were collected from the results of the medical checkup. The subjects were stratified with sex and a Body Mass Index of 25 kg/m(2) to elucidate the effects of birth weight on adult waist-to-height ratio. Analysis of covariance was used to compare the physical condition among the 4 birth weight categories. After adjusting for age, alcohol consumption, smoking status and exercise, the height was significantly lower in the birth weight < 2,500 g category among men (P < 0.001) and women (P < 0.001), while the waist-to-height ratio was significantly higher in the birth weight < 2,500 g category, compared with the > 3,500 g category in the non-obese women (P = 0.004), but not in the obese women. In conclusion, low birth weight was independently associated with a low adult height among men and women and with a high adult waist-to-height ratio among non-obese women. Our results suggest that intrauterine environmental insults might lead to accumulation of visceral fat among non-obese women.

Metabolic Syndrome in Overweight and Obese Japanese Children

OBJECTIVE

To determine the prevalence of and sex differences related to the metabolic syndrome among obese and overweight elementary school children.

RESEARCH METHODS AND PROCEDURES

Subjects were 471 overweight or obese Japanese children. Children meeting at least three of the following five criteria qualified as having the metabolic syndrome: abdominal obesity, elevated blood pressure, low high-density lipoprotein-cholesterol levels, high triglyceride levels, and high fasting glucose levels. Fasting insulin levels were also examined.

RESULTS

Japanese obese children were found to have a significantly lower prevalence (17.7%) of the metabolic syndrome than U.S. obese adolescents (28.7%, p = 0.0014). However, Japanese overweight children had a similar incidence (8.7%) of the metabolic syndrome compared with U.S. overweight adolescents (6.8%). Hyperinsulinemia in girls and abdominal obesity in boys are characteristic features of individual metabolic syndrome factors in Japanese children.

DISCUSSION

The prevalence of the metabolic syndrome is not lower in preteen Japanese overweight children than in U.S. overweight adolescents, although it is significantly lower in Japanese obese preteen children than in U.S. obese adolescents. Primary and secondary interventions are needed for overweight preteen children in Japan.

Growth, body composition and metabolic profile of 8-year-old children exposed to metformin in utero

OBJECTIVES

To investigate the possible long-term effects of metformin exposure on growth and development of the offspring born to mothers with polycystic ovary syndrome (PCOS). The drug passes through the placenta and can potentially influence the fetus.

PATIENTS AND METHODS

This is a follow-up study of a randomized, controlled trial on PCOS women, randomized to metformin or placebo in pregnancy. Out of 37 children aged 7-9 years, 25 agreed to participate. Primary outcome measures were growth, body composition and metabolic parameters.

RESULTS

There were no differences in height, weight or body composition between those exposed to metformin and those exposed to placebo. We found a higher fasting glucose level in the metformin group (4.93 mmol/L vs. 4.60 mmol/L, p = 0.04). In the metformin group there was a trend towards higher systolic blood pressure (106 mmHg vs. 101 mmHg, p = 0.05) and a lower LDL cholesterol level (2.42 mmol/L vs. 2.99 mmol/L, p = 0.07).

CONCLUSION

Metformin exposure during fetal life does not seem to influence growth and body composition at the age of 8 years. A higher fasting glucose level and a possible higher systolic blood pressure and lower LDL cholesterol level in the metformin group may be coincidental and should be further explored.

FTO gene is related to obesity in Chilean Amerindian children and impairs HOMA-IR in prepubertal girls

OBJECTIVE

The objective of this study was to investigate the allelic frequency of the fat mass and obesity-associated (FTO) gene (rs9939609) and its influences on obesity and metabolic risk biomarkers in a cohort of normal weight and obese Chilean children determining its ethnicity.

METHODS

A total of 136 normal weight children and 238 obese children (between 6 and 11 yr old) from an urban setting were recruited for this case-control study. The children were classified as normal weight [body mass index (BMI) ≥ 5th and < 85th percentiles] or obese (BMI >95th percentile), according to the international age- and gender-specific percentiles defined by the Center for Disease Control and Prevention. The analysis of serum markers was carried out using commercial kits. The FTO polymorphism was determined through a high-resolution melting enabled real time polymerase chain reaction. Ethnicity was determined by analyzing mitochondrial DNA by the restriction fragment length polymorphism method.

RESULTS

As much as 85% of the cohort was Amerindian. The minor A allele of rs9939609 was associated with obesity (odds ratio (OR): 1.422 [95% confidence interval (CI) 1.068-1.868] p = 0.015), calculated using an additive model. In sex-stratified analysis we found that the risk variant (A) of rs9939609 was associated with a higher homeostasis model of assessment for insulin (HOMA-IR) in prepubertal obese girls. In male carriers of the A allele, HOMA-IR showed no further deterioration than that already associated with obesity.

CONCLUSIONS

In summary, we confirm the association of the FTO gene single-nucleotide polymorphism rs9939609 with obesity in Chilean Amerindian children. Furthermore we show an association between the risk allele (A) and insulin resistance-related markers in prepubertal obese girls.