Metabolic risk in early childhood: the EarlyBird Study

Development and internal validation of a clinical score to predict neonatal hypoglycaemia in women with gestational diabetes

INTRODUCTION

Gestational diabetes (GD) is a risk factor for neonatal hypoglycaemia (NH), but other factors can increase this risk.

OBJECTIVES

To create a score to predict NH in women with GD.

METHODS

Retrospective study of women with GD with a live singleton birth between 2012 and 2017 from the Portuguese GD registry. Pregnancies with and without NH were compared. A logistic regression was used to study NH predictors. Variables independently associated with NH were used to score derivation. The model's internal validation was performed by a bootstrapping. The association between the score and NH was assessed by logistic regression.

RESULTS

We studied 10216 pregnancies, 410 (4.0%) with NH. The model's AUC was 0.628 (95%CI: 0.599-0.657). Optimism-corrected c-index: 0.626. Points were assigned to variables associated with NH in proportion to the model's lowest regression coefficient: insulin-treatment 1, preeclampsia 3, preterm delivery 2, male sex 1, and small-for-gestational-age 2, or large-for-gestational-age 3. NH prevalence by score category 0-1, 2, 3, 4, and ≥5 was 2.3%, 3.0%, 4.5%, 6.0%, 7.4%, and 11.5%, respectively. Per point, the OR for NH was 1.35 (95% CI: 1.27-1.42). A score of 2, 3, 4, 5 or ≥6 (versus ≤1) had a OR for NH of 1.67 (1.29-2.15), 2.24 (1.65-3.04), 2.83 (2.02-3.98), 3.08 (1.83-5.16), and 6.84 (4.34-10.77), respectively.

CONCLUSION

Per each score point, women with GD had 35% higher risk of NH. Those with ≥6 points had 6.8-fold higher risk of NH compared to a score ≤1. Our score may be useful for identifying women at a higher risk of NH.

Association between foetal sex and adverse neonatal outcomes in women with gestational diabetes

AIMS

Foetal male sex is associated with adverse perinatal outcomes. However, studies evaluating the impact of foetal sex on perinatal outcomes in women with gestational diabetes (GDM) are scarce. We studied whether male new-born sex is associated with neonatal outcomes, in women with GDM.

METHODS

This is a retrospective study based on the national Portuguese register of GDM. All women with live-born singleton pregnancies between 2012 and 2017 were eligible for study inclusion. Primary endpoints under analysis were neonatal hypoglycaemia, neonatal macrosomia, respiratory distress syndrome (RDS) and neonatal intensive care unit (NICU) admission. We excluded women with missing data on the primary endpoint. Pregnancy data and neonatal outcomes between female and male new-borns were compared. Multivariate logistic regression models were built.

RESULTS

We studied 10,768 new-borns in mothers with GDM, 5635 (52.3%) male, 438 (4.1%) had neonatal hypoglycaemia, 406 (3.8%) were macrosomic, 671 (6.2%) had RDS, and 671 (6.2%) needed NICU admission. Male new-borns were more frequently small or large for gestational age. No differences were observed on maternal age, body mass index, glycated haemoglobin, anti-hyperglycaemic treatment, pregnancy complications or gestational age at delivery. In the multivariate regression analysis, male sex was independently associated with neonatal hypoglycaemia [OR 1.26 (IC 95%: 1.04-1.54), p = 0.02], neonatal macrosomia [1.94 (1.56-2.41), p < 0.001], NICU admission [1.29 (1.07-1.56), p = 0.009], and RDS [1.35 (1.05-1.73, p = 0.02].

CONCLUSIONS

Male new-borns have an independent 26% higher risk of neonatal hypoglycaemia, 29% higher risk of NICU admission, 35% higher risk of RDS, and almost twofold higher risk of macrosomia, compared to female new-borns.

Birthweight and Lipids in Adult Life: Population-Based Cross Sectional Study

The purpose of this study was to examine the association of birthweight with lipid profile in the general adult population. Participants in the second-wave of a nationally representative cross sectional AusDiab-study were asked to complete a birthweight questionnaire. Fasting total cholesterol (TC), LDL-C, HDL-C, and triacylglycerol levels were modeled against birthweight. Four thousand five hundred and two people reported their birthweights, mean (SD) of 3.4(0.7) kg. Females with low birthweight-LBW had higher levels of TC, LDL-C, and triacylglycerols, but no difference in HDL-C, than those with normal-birthweight-NBW;≥2.5 kg. People with LBW showed a trend toward increased risk for high TC (≥5.5 mmol/L) compared to NBW. Among females with LBW, the risk for high LDL-C (≥3.5 mmol/L) was increased compared to those of NBW. The risk for low HDL-C (<0.9 mmol/L) was increased among males with LBW compared to those with NBW. Examination of the relationship on the continuum showed no differences except for high triacylglycerol levels among females with the lowest birthweight quintile compared to the higher birthweight quintile. However, the risk for various abnormalities by birthweight quintiles was similar to that when we used the traditional definition of LBW vs. NBW. Females and males with low birthweight differ in their risk for lipids abnormalities. Females had higher risk for high LDL-C, whereas males had high risk for low HDL-C (<0.9 mmol/L). In addition, females with low birthweight had the highest triacylglycerol levels. High LDL-C, low HDL-C, and high triacylglycerols are well-recognized risk factors for cardiovascular disease.

Preschoolers in the Playground: a pilot cluster randomised controlled trial of a physical activity intervention for children aged 18 months to 4 years

Background

The preschool years are considered critical for establishing healthy lifestyle behaviours such as physical activity. Levels of physical activity track through childhood into adulthood and establishing habitual physical activity early in life is therefore vital. Time spent outdoors is associated with greater physical activity and playground interventions have been shown to increase physical activity in school-aged children. There are few preschool, playground-based interventions and these have given inconclusive results. A report published by the UK’s Chief Medical Officer (CMO) highlighted the need for new interventions to promote movement in the early years (0–5 years).

Objectives

This study aimed to undertake a pilot cluster randomised controlled trial (RCT) of an outdoor playground-based physical activity intervention for parents and their children aged from 18 months to 4 years (Preschoolers in the Playground or PiP) and to assess the feasibility of conducting a full-scale cluster RCT.

Design

The study was a two-armed pilot cluster RCT with economic and qualitative evaluations. Participants were randomised on a 1 : 1 basis to the PiP intervention (n = 83) or usual practice (control;n = 81).

Setting

Bradford, West Yorkshire, UK.

Participants

Children aged from 18 months to 4 years.

Intervention

The PiP intervention is grounded in behavioural theory (social cognitive theory) and is in accordance with CMO guidance for physical activity in the early years. It is informed by existing literature and data collected from focus groups with parents. The intervention was delivered in primary school playgrounds. Six 30-minute PiP sessions per week were available for 30 weeks; families were encouraged to come to three a week. The 10-week initiation phase was facilitated by a member of school staff and the maintenance phase was unsupervised.

Main outcome measures

Recruitment and retention of schools and families to the trial were the main outcome measures. The acceptability of trial procedures and the intervention, the feasibility of collecting health outcome data and the fidelity of the implementation of the intervention were also evaluated. A preliminary assessment of cost-effectiveness and a sample size calculation for a full trial were conducted.

Results

In total, 37% of schools and 48% of parents approached agreed to take part. Levels of retention were good at 10 and 52 weeks’ follow-up (82.3% and 83.5% respectively). Both the trial procedures and the intervention were acceptable. However, attendance was low during the autumn and winter/spring initiation phases but somewhat better in the summer initiation phase. Attendance was poor throughout all maintenance phases. The accelerometry protocol for measuring physical activity requires modification. The fidelity of intervention implementation was good (81% adherence). The intervention was borderline cost-effective. A sample size of 600 children from 38 schools is required for a full trial.

Conclusion

A full RCT of the PiP intervention is feasible. The PiP intervention requires some modification, for example running the intervention during the summer term only, but was found to be acceptable to schools and families.

Trial registration

Current Controlled Trials ISRCTN54165860.

Funding

This project was funded by the NIHR Public Health Research programme and will be published in full inPublic Health Research; Vol. 3, No. 5. See the NIHR Journals Library website for further project information.

Plasma non-esterified fatty acid levels in children and their relationship with sex steroids

OBJECTIVE

Puberty is associated with decreased insulin sensitivity. Sexual hormones have been related with the onset of insulin resistance, but their relationship with non-esterified fatty acids (NEFA) remains unexplored. The aim of this study was to evaluate circulating NEFA levels in population-based samples of prepubertal children and adolescents and to analyze the association of NEFA with obesity, insulin resistance, and sexual hormones in adolescents.

EXPERIMENTAL

The studied population included 854 randomly selected 6-8-year-old children and 822 children aged 12-16years. NEFA levels were determined using a commercial kit. Testosterone and estradiol levels were determined by RIA, and insulin and sex hormone binding protein by IRMA. HOMA was calculated as an indicator of insulin resistance.

RESULTS

NEFA levels were lower in adolescents than in 6-8-year-old children, and decreased progressively with age between 12-year-olds and 16-year-olds. No significant differences in NEFA levels were observed between obese and non-obese adolescents. NEFA were not correlated with insulin or HOMA in 12-16-year-old girls, and appear negatively correlated with these variables in boys. Insulin and HOMA were negatively correlated with SHBG levels in both sexes adjusting by age but NEFA levels were not.

CONCLUSIONS

NEFA levels decrease with age in adolescents and are not significantly increased in obese children, supporting the fact that the decreased insulin sensitivity at this age is not affecting NEFA metabolism. Although SHBG is related to insulin and HOMA independently of age in both sexes, SHBG levels are not associated with NEFA.

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.

Biological correlates and predictors of insulin resistance among early adolescents

Abnormal glucose metabolism is associated with obesity, insulin resistance (IR), and Type 2 diabetes mellitus. The purposes of this study were to describe anthropometric and laboratory markers of adolescents, examine correlates of IR, and test ability of anthropometric and laboratory markers to predict risk of exhibiting IR. A total of 150 early adolescents participated. Participants with obesity had increased IR, high-sensitivity C-reactive protein, triglycerides, and blood pressure. Waist circumference and triglycerides were predictive of IR. Multiple risk factors compound and lead to long-term health consequences among youth. Nurses can evaluate these factors to identify IR.

Country-specific birth weight and length in type 1 diabetes high-risk HLA genotypes in combination with prenatal characteristics

OBJECTIVE

To examine the relationship between high-risk human leukocyte antigen (HLA) genotypes for type 1 diabetes and birth size in combination with prenatal ch aracteristics in different countries.

STUDY DESIGN

Four high-risk HLA genotypes were enrolled in the Environmental determinants of Diabetes in the Young study newborn babies from the general population in Finland, Germany, Sweden and the United States. Stepwise regression analyses were used to adjust for country, parental physical characteristics and environmental factors during pregnancy.

RESULT

Regression analyses did not reveal differences in birth size between the four type 1 diabetes high-risk HLA genotypes. Compared with DQ 4/8 in each country, (1) DQ 2/2 children were heavier in the United States (P=0.028) mostly explained however, by parental weight; (2) DQ 2/8 (P=0.023) and DQ 8/8 (P=0.046) children were longer in Sweden independent of parents height and as well as (3) in the United States for DQ 2/8 (P=0.023), but again dependent on parental height.

CONCLUSION

Children born with type 1 diabetes high-risk HLA genotypes have comparable birth size. Longitudinal follow-up of these children should reveal whether birth size differences between countries contribute to the risk for islet autoimmunity and type 1 diabetes.

A review of resistance exercise training in obese adolescents

Resistance training-also known as strength or weight training-has been well recognized by several national organizations as a safe and beneficial exercise modality for the health and well-being of children and adolescents. Resistance exercise improves muscular strength and can improve body composition (eg, increase lean body mass and decrease percent body fat) provided that a sufficient exercise stimulus is prescribed. Effects of resistance exercise training on body composition and metabolic profile are well established in obese adults, but warrant further investigation in obese youth. This article reviews the rationale for including a resistance training component with interventions geared toward overweight and obese adolescents by discussing the effects on various health measures. Shortcomings in published trials, including small, ethnic minority samples of short-duration and low-frequency exercise sessions primarily conducted in prepubertal youth (rather than postpubertal adolescents) limit the generalizability of the published literature on the effectiveness of resistance exercise in obese adolescents.

Thin newborns are more insulin resistant at 10 years of age

AIMS

To investigate the relation between ponderal index or birth weight and insulin resistance in late childhood.

METHODS

An observational study of 92-term appropriate-for-gestational age infants was carried out. Weight and length were measured at birth and at 9 months and duration of breast feeding was noted at 9 months. Follow-up examinations at 10 years of age included measurement of weight, height, pubertal status, fasting insulin and glucose concentrations.

RESULTS

Ponderal index at birth was negatively (B±SE=-0.05±0.02; p=0.025) and current BMI was positively (B±SE=0.14±0.02; p<0.001) associated with insulin resistance measured as homeostasis model assessment (HOMA) at 10 years of age adjusted for gender and pubertal stage. Current BMI and ponderal index at birth were still significant after adjusting for weight at 9 months. Birth weight and weight at 9 months was not correlated with HOMA (p=0.58) adjusted for current BMI, gender and pubertal stage. HOMA was higher in the tertile with the lowest ponderal index than in the two remaining tertiles (p=0.024).

CONCLUSION

Relative thinness at birth, but neither birth weight nor weight gain from 0-9 months, was associated with higher insulin resistance at 10 years of age in this cohort with a low prevalence of overweight at 10 years of age and normal birth weight.

The prediction of preschool children's weight from family environment factors: gender-linked differences

The main objective of this study was to test an explanatory model predicting preschool girls' and boys' body weight from certain child variables (food intake, sedentary behaviors, and eating habits), as well as family variables (interaction during mealtime and level of family financial resources allocated to meeting children's eating needs). A randomized stratified subsample of parents was selected from a larger study (Quebec Longitudinal Study of Child Development, QLSCD-1998-2002), with a breakdown of 581 girls and 611 boys of 4 years of age. Children's skin fold ratio, weight, height, and Body Mass Index (BMI) were recorded. Questionnaires were administered to parents (usually the mother). Using structural equation modeling (SEM) separately for girls and boys, the family environment model of healthy weight development was tested. Results yielded a good fit of the model for both genders. For boys, significant predictors of body weight in the model were family food insecurity and conflicts during mealtime. Healthy eating was predicted by food insecurity, mealtime conflicts, and sedentary behaviors. Mealtime conflicts predicted sedentary behaviors. For girls, none of the variables predicted body weight, however food insecurity predicted less healthy eating. These results outline the importance of prevention and intervention within families with young children.

Determination of the BMI threshold that predicts cardiovascular risk and insulin resistance in late childhood

AIMS

Body mass index (BMI, kg/m(2)) thresholds of children predicting cardiovascular risk, reported in previous studies were inconsistent and that predicting increased insulin resistance is lacking. We determined the BMI threshold that predicts increased cardiovascular risk and insulin resistance in children.

METHODS

The entire 4th grade students (187 boys and 218 girls) from 5 schools were included. Cardiovascular risk was defined as the presence of three or more of cardiovascular risk factors. Increased insulin resistance was estimated using homeostasis model assessment of insulin resistance and fasting insulin level.

RESULTS

The BMI percentile predicting cardiovascular risk was the 71.3th percentile for boys and the 77.1th percentile for girls. The BMI value was 21.4 kg/m(2) for boys and 20.6 kg/m(2) for girls. 34% of boys and 42% of girls with a BMI above the cut-off values had cardiovascular risk. The BMI percentile predicting increased insulin resistance was the 66.3th percentile for boys and the 67.9th percentile for girls. The children with cardiovascular risk had significantly greater (P<0.01) insulin resistance than those without risk.

CONCLUSION

This study demonstrated that the BMI thresholds at which cardiovascular risk and insulin resistance begin to increase in Korean children were lower than current definition of childhood obesity, proposed by the international obesity task force.

The relationship between birth weight and insulin resistance in childhood

Chronic diseases that are typical of adulthood may originate in intra-uterine life through inadequate fetal development. The present epidemiological cohort study of 506 healthy children aged 5–8 years evaluated the relationship between birth weight and insulin resistance in an age group that has been assessed in few similar studies. Insulin concentration was determined by chemiluminescence and insulin resistance by the homeostasis model assessment (HOMA). Blood glucose, total cholesterol and fractions (LDL cholesterol and HDL cholesterol) and TAG concentrations were determined by automated enzymatic methods. Linear regression analysis investigated the relationship between birth weight (assessed as a continuous variable and in three categories: small for gestational age, SGA; adequate for gestational age and large for gestational age) and the HOMA index, using backward stepwise selection and biological models to explain the causal pathway of the relationship. There were negative associations between birth weight (P < 0·001), SGA (P = 0·027) and the HOMA index, and a positive association between waist circumference (P < 0·001) and the HOMA index. Considering the significant associations between birth weight and waist circumference (P < 0·001) and waist circumference and insulin resistance (P < 0·001), we can probably suspect that lower birth weight is a common cause of higher waist circumference and insulin resistance. In summary, the results of the present study showed increased insulin resistance in apparently healthy, young children, who had lower weight at birth and higher measurements of waist circumference. There is a need to develop public health policies that adopt preventive measures to promote adequate maternal-fetal and child development and enable early diagnosis of metabolic abnormalities.

Age at diagnosis, gender, and metabolic control in children with type 1 diabetes

OBJECTIVE

To examine whether age at diagnosis and gender affect early metabolic control in children with type 1 diabetes.

DESIGN AND METHODS

Data on age at diagnosis, gender, pubertal status, and metabolic control were gathered by a retrospective chart review of children diagnosed between 1992 and 2005. Mean hemoglobin A1c (HbA1c) values were compared at five time points: at diagnosis and at 6, 12, 24, and 36 months after diagnosis.

RESULTS

At diagnosis, girls aged 6-12 years presented with significantly higher HbA1c levels than girls diagnosed at older or younger ages. Their HbA1c at diagnosis was also significantly higher than that in boys of the same age. There was no gender difference among children diagnosed at ages 0-5 or 13+ yr. At 6 months after diagnosis, only age at diagnosis was associated with metabolic control, with children diagnosed when older presenting with lower HbA1c levels. At 12, 24, and 36 months after diagnosis, there were no significant effects of age at diagnosis or gender on glycemic status.

CONCLUSION

At initial diagnosis, girls in the 6-12 age group presented with higher HbA1c levels compared with boys and girls of other age groups. Although endocrine changes associated with puberty may partly explain the findings, more investigation to elucidate mechanisms accounting for the interaction of age and gender with glycemic status is needed.

Resting energy expenditure in insulin resistance falls with decompensation of insulin secretion in obese children

BACKGROUND

Low resting energy expenditure (REE) and respiratory quotient (RQ) have been shown in adults to predispose to obesity and diabetes mellitus.

AIM

To correlate REE and RQ in 73 obese children and young adults (body mass index [BMI] 37 +/- 10 kg/m2) with measures of insulin secretion and resistance (IR) indices, percent carbohydrate and fat oxidation, and prolactin and leptin levels.

DESIGN

During a 3-day admission, REE and RQ were determined by indirect calorimetry. Blood chemistries and oral glucose tolerance test (OGTT) were obtained, and intravenous glucose tolerance test (IVGTT) modified by tolbutamide was conducted after an overnight fast, permitting calculation of acute insulin response (AIR), insulin resistance (SiIVGTT), and disposition index (DI).

RESULTS

Patients fell into two groups according to their SiIVGTT: those with normal insulin sensitivity (NIS) and those with insulin resistance (IR). IR patients were subdivided on the basis of DI (cut-off value 0.13 min(-1)) into compensated (CIR) or decompensated (DIR) groups. CIR patients had higher RQ, REE corrected by BMI, AIR, and carbohydrate oxidation and lower fat oxidation than NIS and DIR patients. REE correlated positively with BMI, leptin, and AIR, and negatively with SiIVGTT.

CONCLUSIONS

Findings in the CIR and DIR groups support the correlation of REE with metabolic changes consistent with an increased risk of diabetes mellitus.

Size at birth, obesity and blood pressure at age five

BACKGROUND

The fetal origins hypothesis indicates that morphometric evidence of fetal nutritional deprivation is predictive of excessive weight gain/obesity, insulin resistance, and cardiovascular disease after birth. However, it is unclear whether these effects are present in offspring with "normal" birth weights in contemporary Western society, whether they are population specific, and how early in life they appear. This study was designed to examine these questions in a select populace of morphometrically diverse offspring to test the null hypothesis that morphometric evidence of nutritional restriction in utero has no effect on the presence of either obesity or increased blood pressure at ages 5 and 6.

METHODS

We present a prospective study of 101 offspring born of well-nourished, middle and upper socioeconomic-class women who participated in studies of diet and exercise during pregnancy. At birth and age 5 to 6 the offspring underwent morphometric evaluation with the additional measurement of blood pressure at age 5 to 6.

RESULTS

There were no significant negative correlations between neonatal morphometrics and either blood pressure or obesity at age 5 to 6. There were, however, direct positive correlations between birth weight and both weight and BMI at age 5 to 6 (p < 0.0001).

CONCLUSIONS

In this specific populace, morphometrics at age 5 to 6 correlated with size at birth. However, there was no relationship between mophometric evidence of in utero nutritional deprivation at birth and either blood pressure or obesity at age 5 to 6.

Disorders of glucose regulation in adults and birth weight: results from the Australian Diabetes, Obesity and Lifestyle (AUSDIAB) Study

OBJECTIVE

The purpose of this study was to examine the association of birth weight with indexes of glycemia in a population-based survey.

RESEARCH DESIGN AND METHODS

A total of 10,788 participants in the Australian Diabetes, Obesity and Lifestyle (AusDiab) Study were asked to complete a birth weight questionnaire. Fasting plasma glucose (FPG), postload glucose (PLG), and A1C were modeled against birth weight. World Health Organization criteria were used to define impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and diabetes.

RESULTS

Among 7,157 participants who responded to the questionnaire, 4,502 reported their birth weights, with a mean +/- SD of 3.4 +/- 0.7 kg. FPG, PLG, and A1C were strongly and inversely correlated with birth weight. The odds ratios (95% CI) for high (>90th sex-specific percentile) FPG, PLG, and A1C were 0.83 (0.71-0.96), 0.74 (0.65-0.84), and 0.81 (0.70-0.94), respectively, for a 1-kg increase in birth weight after adjustment for age and sex. In those with low birth weight (LBW), the risks for having IFG, IGT, and diabetes and for all abnormalities combined were increased by 1.75, 2.22, 2.76, and 2.28, respectively, for women and by 1.40, 1.32, 1.98, and 1.49 for men compared with risks for those with normal birth weight. These trends applied across categories of age and BMI.

CONCLUSIONS

In an affluent Western country with a good adult health profile, birth weight has an inverse relationship with indexes of glycemia, and individuals with LBW were predisposed to higher rates of glycemic dysregulation in adult life. These associations were independent of BMI and of other factors significantly correlated with glycemic dysregulation.

[Food consumption of children and adolescents in Germany. Results of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS)]

Since dietary behaviour has an essential impact on health, information on food consumption was obtained in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). The average food frequency and portion size "in recent weeks" was assessed with a food frequency questionnaire. Two versions of the questionnaire, identical in content, exist: one aimed at parents of 1-10-year-olds and the other directly at 11-17-year-olds. The results include data on 7,186 boys and 6,919 girls, aged 3-17. About half of the participants each consume bread, milk and fresh fruits every day. The majority (about three quarter) eat fast food only once a month or less. However, 16 % of the participants eat chocolate, and almost 20 % other sweets every day. More boys than girls individually consume soft drinks, milk, dairy products, meat, sausage, cereals and white bread every day. More girls consume fresh fruits and raw vegetables each day. With increasing age the proportion of daily consumers of soft drinks, cheese (and among boys also meat and sausage) increases, but the proportion of daily consumers of juices, tap water, milk, dairy products, fresh fruits, raw vegetables, cookies, chocolate, sweets (and among girls also breakfast cereals) falls. As expected the consumption of sweets and soft drinks is relatively high. Whereas more than half of the children each consume fruits and vegetables on a daily base, this consumption declines with increasing age.

The gender insulin hypothesis: why girls are born lighter than boys, and the implications for insulin resistance

Girls are born lighter than boys. The consistency of this observation across different populations is striking, suggesting that it may have fundamental significance for those conditions linked with lower birth weight, such as diabetes. Previous hypotheses relating low birth weight to subsequent diabetes have addressed differences in insulin resistance within the sexes, not between them. Here, we propose that gender-specific genes affecting insulin sensitivity are responsible for the gender difference in birth weight--the genetically more insulin resistant female fetus is less responsive to the trophic effects of insulin and is therefore smaller. These genes also render female subjects more susceptible to diabetes, explaining why reports of type 2 diabetes (T2D) in younger populations show a female preponderance. Consistent with our proposal, concentrations of insulin and/or its propeptides are higher at birth in female populations and they are intrinsically more insulin resistant throughout life, with attendant impact on their metabolism, and the regressions describing the relationship between insulin resistance and adiposity in female and male subjects have similar gradients, but different constants. These gender-specific genes have a demonstrable impact on fetal growth and insulin resistance. Diabetes and cardiovascular disease are thought to be driven by insulin resistance, and the observations reported here may help to focus the search for genes that control it.

A common haplotype of the glucokinase gene alters fasting glucose and birth weight: association in six studies and population-genetics analyses

Fasting glucose is associated with future risk of type 2 diabetes and ischemic heart disease and is tightly regulated despite considerable variation in quantity, type, and timing of food intake. In pregnancy, maternal fasting glucose concentration is an important determinant of offspring birth weight. The key determinant of fasting glucose is the enzyme glucokinase (GCK). Rare mutations of GCK cause fasting hyperglycemia and alter birth weight. The extent to which common variation of GCK explains normal variation of fasting glucose and birth weight is not known. We aimed to comprehensively define the role of variation of GCK in determination of fasting glucose and birth weight, using a tagging SNP (tSNP) approach and studying 19,806 subjects from six population-based studies. Using 22 tSNPs, we showed that the variant rs1799884 is associated with fasting glucose at all ages in the normal population and exceeded genomewide levels of significance (P=10-9). rs3757840 was also highly significantly associated with fasting glucose (P=8x10-7), but haplotype analysis revealed that this is explained by linkage disequilibrium (r2=0.2) with rs1799884. A maternal A allele at rs1799884 was associated with a 32-g (95% confidence interval 11-53 g) increase in offspring birth weight (P=.002). Genetic variation influencing birth weight may have conferred a selective advantage in human populations. We performed extensive population-genetics analyses to look for evidence of recent positive natural selection on patterns of GCK variation. However, we found no strong signature of positive selection. In conclusion, a comprehensive analysis of common variation of the glucokinase gene shows that this is the first gene to be reproducibly associated with fasting glucose and fetal growth.

Insulin and HOMA in Spanish prepubertal children: relationship with lipid profile

OBJECTIVE

The effects of insulin or insulin resistance on the lipid profile seem to change with age. The aim of this study was to analyze insulin levels and an insulin resistance index and to investigate the relationship between these and the lipid profile in a population-based sample of Spanish prepubertal children.

METHODS

1048 (524 boys and 524 girls) randomly selected prepubertal children were studied. Children were 6 to 8 years old with a mean age of 6.7. Plasma lipid, FFA and insulin levels were measured. The homeostatic model assessment (HOMA) was calculated as an indicator of insulin resistance.

RESULTS

When analyzing percentile values of insulin, HOMA and FFA by sex, we observed that girls had significantly higher insulin concentrations than boys (except at the 10th percentile) and significantly higher FFA (except at the 90th percentile) with no significant differences between sexes for HOMA. Multivariate regression analyses showed that insulin was positively associated with glucose, triglycerides and apoB in boys but not in girls, and negatively associated with FFA in both genders.

CONCLUSIONS

We report here data about the distribution of insulin in the Spanish prepubertal population. The higher levels of insulin in prepubertal girls could indicate that girls start to be more insulin resistant than boys at this age, although other manifestations of insulin resistance are not yet detectable.

The influence of sex on the protein anabolic response to insulin

We hypothesize that sex influences whole-body protein anabolism in the postabsorptive state and in response to hyperinsulinemia. Kinetics of 3-(3)H-glucose and (13)C-leucine were studied in 16 men and 15 women after energy- and protein-controlled diets, before and during a hyperinsulinemic, euglycemic, isoaminoacidemic clamp. In the postabsorptive state, women had 20% higher rates of leucine Ra (protein breakdown) and nonoxidative Rd (synthesis) adjusted for fat-free mass than men but net leucine balance was as negative. In response to hyperinsulinemia, leucine oxidation rates increased only in women and the change in net leucine balance was less than in men. Net leucine balance during the clamp correlated with rates of glucose disposal. Thus, women showed greater protein turnover rates when adjusted for fat free mass in the postabsorptive state, and lesser insulin sensitivity of protein anabolism and net protein accretion. A relationship exists between the protein anabolic response to insulin and the insulin sensitivity of glucose metabolism.