Birth weight and risk of adiposity among adult Inuit in Greenland

Skeletal and Adipose Manifestations of Stress in a Contemporary Pediatric Sample

INTRODUCTION

Adverse experiences leading to physiological disruptions (stress) in early life produce cascade effects on various biological systems, including the endocrine and metabolic systems, which, in turn, shape the developing skeletal system. To evaluate the effects of stress on adipose and skeletal tissues, we examine the relationship between skeletal indicators of stress (porotic hyperostosis [PH] and cribra orbitalia [CO]), bone mineral density (BMD), vertebral neural canal (VNC) diameters, and adipose tissue distribution in a contemporary pediatric autopsy sample.

METHODS

Data is from 702 (409 males, 293 females) individuals from a pediatric (0.5-20.9 years) autopsy sample from New Mexico who died between 2011 and 2022. Data includes visceral adipose tissue (VAT) in the abdomen, heart, and liver, CO/PH, VNC size of the fifth lumbar vertebra, and BMD.

RESULTS

We find that adipose tissue distribution and location are differentially associated with CO/PH, BMD, and VNC size; VNC size is smaller, and liver adiposity is higher in those with CO/PH. Further, increased VAT and small VNC size are associated with PH presence and low BMD. Body mass index categories do not correspond with porous cranial lesion presence.

CONCLUSIONS

This paper provides evidence for the complex relationship between skeletal markers of early-life stress (CO/PH, reduced VNC size, low BMD) and endocrine system function. VAT distribution and VNC size are partly shaped by stressors during gestation, likely through alterations of the HPA axis. It is possible that alterations of the HPA axis due to gestational stress also shape the expression of porous cranial lesions during exposure to childhood stressors.

Life-course obesity and heart failure: a two-sample Mendelian randomization study

Heart failure is a multifaceted clinical syndrome, with obesity identified as a significant modifiable risk factor. This study employed a two-sample Mendelian randomization (MR) design, incorporating obesity data across life stages, to elucidate the causal link between obesity and heart failure. Data on heart failure from the 2023 Finngen database and genetic predictors of obesity from the IEU OpenGWAS project were analyzed using the IVW method, MR-Egger regression, weighted median, simple mode, weighted mode, and scatter plots. Heterogeneity was assessed with Cochran's Q test, and horizontal pleiotropy with MR-Egger intercept test. Sensitivity to single-nucleotide polymorphisms (SNPs) was tested via leave-one-out analysis, and funnel plots were utilized for visual inspection of horizontal pleiotropy. Statistical powers were also calculated. The MR analysis findings indicate a significant relationship between birth weight and the likelihood of developing heart failure (Odds Ratio [OR] 1.134, 95% Confidence Interval [CI] 1.033-1.245, P = 0.008). In addition, a heightened childhood BMI was found to be a significant predictor of heart failure risk (OR 1.307, 95% CI 1.144-1.494, P = 8.51E-05), as was childhood obesity (OR 1.123, 95% CI 1.074-1.173, P = 2.37E-07). Furthermore, adult BMI sex-combined exhibited a strong correlation with the risk of heart failure (OR 2.365, 95% CI 2.128-2.629, P = 1.91E-57). Sensitivity analyses provided further support for the reliability of these results, with no significant indication of horizontal pleiotropy observed. This study shows that obesity, including childhood obesity, is linked to a higher risk of heart failure. These findings highlight the urgent need for early weight management interventions in public health and clinical settings to reduce heart failure rates.

Small for gestational age and anthropometric body composition from early childhood to adulthood: the Aboriginal Birth Cohort study

Background

In Australia the estimated rate of small for gestational age (SGA) births is 9% among non-Indigenous births compared to 14% among Aboriginal and Torres Strait Islanders. There is limited research investigating the effect of being born SGA on body composition later in life in Indigenous Australians.

Methods

Using data from the Aboriginal Birth Cohort longitudinal study, we compared the body composition of those born SGA to non-SGA by analysing anthropometric measures (height, weight, waist circumference, fat percentage [FAT%], body mass index [BMI], waist-to-height ratio, and A body shape index [ABSI]) collected at four follow-up periods (from childhood to adult). For cross-sectional analyses, linear regression models were employed to assess factors associated with anthropometric measures. For longitudinal analyses linear mixed models were employed to assess differences in anthropometric measures among SGA versus non-SGA individuals while adjusting for repeated measures.

Results

The analytic baseline cohort were those who participated in Wave 2 (n = 570). In cross-sectional analyses, across all waves those born SGA had smaller anthropometric z-scores compared to non-SGA individuals (β ranging from -0.50 to -0.25). Participants residing in urban environments were significantly larger in Waves 2 to 4 (β ranged 0.26 to 0.65). Those born SGA had higher ABSI scores in Waves 2 and 4 (β 0.26 and 0.37, respectively). In longitudinal analyses, those born SGA had smaller measures of body composition across the life course; these differences were larger in urban communities. In remote communities those born SGA had significantly higher ABSI scores during adolescence and young adulthood, and this difference was not observed in urban communities.

Conclusion

Indigenous Australians born SGA are smaller anthropometrically later in life compared to their non-SGA counterparts. In remote communities, those born SGA had higher levels of central adiposity compared to non-SGA.

No association between early maternal HbA1c and offspring birthweight among women without pre-existing diabetes in Greenland

Studies of the association between maternal blood glucose measured by glycated haemoglobin (HbA1c) during pregnancy and the offspring’s birthweight have been heterogeneous. The aim of this study was to examine the association between maternal HbA1c level before gestational week 20 and the offspring’s birthweight among predominantly indigenous women in Greenland. A retrospective cohort study including all women (n = 503) and their offspring delivered from September 2015 to September 2016 at Queen Ingrid’s Hospital in Nuuk was conducted. Data were obtained from the electronic medical record. Linear regression models were used to analyse the effect of maternal HbA1c on the offspring’s birthweight with adjustment and stratification for relevant confounders and effect modifiers. Birthweight increased with 3.3 g per mmol/mol increase in HbA1c. Yet, no significant association between maternal HbA1c and the offspring’s birthweight was found after adjustment for maternal age, ethnicity, residence, smoking, and parity (β = 0.058, p = 0.711). Among obese women, a borderline significant positive association (β = 0.657, p = 0.059) was found. For term newborns, this corresponded to an increase in birthweight of 31 g per mmol/mol increase in HbA1c. Based on the current study, the use of HbA1c during pregnancy to detect the risk of delivering a newborn with macrosomia is not recommended in Greenland.

Abbreviation: HbA1c: glycosylated haemoglobin; GA: gestational age; SD: standard deviation; CI: confidence interval.

Adult-Onset Diseases in Low Birth Weight Infants: Association with Adipose Tissue Maldevelopment

Low birth weight (LBW) infants have higher risk of developing insulin resistance and its comorbidities later in life. The concept of “developmental origins of health and disease” suggests that intrauterine and postnatal environments have an important role in increasing these risks. The risk of such adult-onset diseases in LBW infants might be associated with adipose tissue maldevelopment including altered body composition and increased amount of visceral fat, which is the same mechanism as that in children and adults with metabolic syndrome. However, LBW infants often have different characteristics: they are not always overweight or obese over their life course. The inconsistency might be associated with the thrifty phenotype, which is produced in response to impaired growth potential and decreased lean body mass. LBW infants tend to be obese within the limits of impaired growth potential. Through our previous investigations evaluating longitudinal changes in adiponectin levels at an early stage of life, we speculated that probably, the intrauterine life of term infants or the period up to term-equivalent age in preterm infants might be the key age for the development of adipose tissues including fat cells. Because of that, we hypothesized that the smaller number of adipocytes in LBW infants might be associated with overloading of single adipocytes and impaired adipose tissue expandability. The possible mechanisms are discussed from the perspective of adipose tissue maldevelopment in LBW infants.

From conception to infancy - early risk factors for childhood obesity

Maternal lifestyle during pregnancy, as well as early nutrition and the environment infants are raised in, are considered relevant factors for the prevention of childhood obesity. Several models are available for the prediction of childhood overweight and obesity, yet most have not been externally validated. Moreover, the factors considered in the models differ among studies as the outcomes manifest after birth and depend on maturation processes that vary between individuals. The current Review examines and interprets data on the early determinants of childhood obesity to provide relevant strategies for daily clinical work. We evaluate a selection of prenatal and postnatal factors associated with child adiposity. Actions to be considered for preventing childhood obesity include the promotion of healthy maternal nutrition and weight status at reproductive age and during pregnancy, as well as careful monitoring of infant growth to detect early excessive weight gain. Paediatricians and other health-care professionals should provide scientifically validated, individual nutritional advice to families to counteract excessive adiposity in children. Based on systematic reviews, original papers and scientific reports, we provide information to help with setting up public health strategies to prevent overweight and obesity in childhood.

Gestational diabetes and macrosomia among Greenlanders. Time to change diagnostic strategy?

Gestational diabetes mellitus (GDM) is a serious condition associated to both maternal and offspring complications. Yet, no globally accepted consensus exists on how to test and diagnose GDM. In Greenland, the clinical criteria for testing and diagnosing GDM are adapted from Danish guidelines. The aim of this study was to estimate the prevalence of GDM among Greenlanders using both the current clinical GDM criteria and the recent WHO 2013 criteria and, further, to study the association between GDM, pre-pregnant overweight or obesity and macrosomia. A cross-sectional study of all 450 Greenlandic women who gave birth to a singleton in Nuuk within 1 year was performed. Based on an oral glucose tolerance test measuring capillary whole blood glucose, 119 women were categorised as having clinical GDM, WHO 2013 GDM or not GDM. Macrosomia defined as birth weight above 4,000 g was used as outcome variable. The prevalence of clinical GDM and WHO 2013 GDM was 0.4% (95% CI; 0-1.1) and 6.9% (95% CI; 4.5-9.2). WHO 2013 GDM, fasting blood glucose, pre-pregnant maternal overweight and obesity were associated with macrosomia. WHO 2013 GDM criteria were superior to clinical criteria in predicting macrosomia indicating that it may be time to consider the diagnostic strategy used in Greenland. Pre-pregnant overweight may also need more intensified lifestyle-intervention.

ABBREVIATIONS

GDM: Gestational diabetes mellitus; VP: venous plasma; CWB: capillary whole blood; OGTT: oral glucose tolerance test; WHO: World Health Organisation; FIGO: The International Federation of Gynaecology and Obstetrics; BMI: body mass index; GA: gestational age.

Associations between birth weight and glucose intolerance in adulthood among Greenlandic Inuit

AIMS

To examine the association between birth weight and glucose intolerance in adult Greenlandic Inuit.

METHODS

We examined 1429 participants aged 18-56 years from two population-based, cross-sectional studies in Greenland with information on birth weight. Oral glucose tolerance tests, anthropometric measures and ultrasound of abdominal tissue were performed. Associations of birth weight with glucose markers were analysed using linear or logistic regressions. Spline analyses were conducted to examine u-shaped associations. Adjustments were done for age, sex, birth place, family history of diabetes, genetic admixture, TBC1D4 p.Arg684Ter carrier status, BMI and visceral adipose tissue.

RESULTS

The median birthweight was 3300 g and 3.9% had type 2 diabetes, T2DM. Spline analyses indicated overall linear associations. In fully adjusted analyses, an increase in birth weight of 1 kg was associated with a change in fasting plasma glucose of -0.06 mmol/L (95%CI: -0.11, -0.01), 2-h plasma glucose of -0.16 mmol/L (95%CI: -0.35, 0.02), HOMA-IR of -5.45% (95%CI: -10.34, -0.29), insulin sensitivity index of 7.04% (95%CI: 1.88, 12.45) and a trend towards a reduced risk of hyperglycaemia and T2DM, although statistically insignificant.

CONCLUSIONS

Birth weight was inversely associated with hepatic and peripheral insulin resistance independently of adult adiposity. Thus, the findings support low birth weight as a contributing factor for glucose intolerance in adult Inuit in Greenland.

Nonlinear Relationship between Birth Weight and Visceral Fat in Adolescents

OBJECTIVE

To determine the association of birth weight with abdominal fat distribution and markers known to increase risk for cardiovascular disease and type 2 diabetes in adolescents.

STUDY DESIGN

In 575 adolescents aged 14-18 years (52% female, 46% black), birth weight was obtained by parental recall. Fasting blood samples were measured for glucose, insulin, lipids, adiponectin, leptin, and C-reactive protein. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed by magnetic resonance imaging.

RESULTS

When we compared markers of cardiometabolic risk across tertiles of birth weight, adjusting for age, sex, race, Tanner stage, physical activity, socioeconomic status, and body mass index, there were significant U-shaped trends for homeostasis model assessment of insulin resistance, leptin, and visceral adipose tissue (all Pquadratic < .05). A significant linear downward trend across tertiles of birth weight was observed for triglycerides (Plinear = .03). There were no differences in fasting glucose, blood pressure, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, adiponectin, C-reactive protein, or subcutaneous abdominal adipose tissue across tertiles of birth weight.

CONCLUSIONS

Our data suggest that both low and high birth weights are associated with greater visceral adiposity and biomarkers implicated in insulin resistance and inflammation in adolescents.