Maternal pregravid weight is the primary determinant of serum leptin and its metabolic associations in pregnancy, irrespective of gestational glucose tolerance status

Association of gestational metabolic syndrome with the Chinese Healthy Eating Index in mid-pregnancy: a cross-sectional study

BACKGROUND

This study aims to investigate the relationship between gestational metabolic syndrome (GMS) and the Chinese Healthy Eating Index (CHEI) in mid-pregnancy, and to identify potentially beneficial or high-risk dietary habits. We have developed a mid-pregnancy version of CHEI-2022, adapting the Chinese Healthy Eating Index to align with the food quantity recommendations outlined in the 2022 Dietary Guidelines for Chinese Residents for mid-pregnancy.

METHODS

Using the inclusion and exclusion criteria, data from 2411 mid-pregnant individuals were collected through interviews. The Total CHEI score and its component scores were determined through analysis of responses from the food frequency questionnaire. GMS diagnosis involved conducting physical examinations and performing blood biochemical tests. A logistic regression model was employed to analyze the relationship between GMS or related indices and both the total CHEI score and its component scores.

RESULTS

The study identified an overall GMS prevalence of 21.65% (522 out of 2411 participants). During mid-pregnancy, participants diagnosed with GMS exhibited higher BMI, FBG, 1hPBG, 2hPBG, TC, TG, HDL, SBP, as well as higher educational levels and daily activity, compared to those without GMS (P < 0.001). After adjusting for potential confounders, participants with higher total CHEI scores (≥ 80) were found to have lower odds of GMS or related indices (P < 0.05). Increasing dietary intake of potatoes, whole grains, beans, dark green vegetables, and fruits, as per the CHEI recommendations, was associated with reduced odds of GMS or related indices (P < 0.05).

CONCLUSION

A high-quality diet, as indicated by a total CHEI score of 80 or higher, and increased consumption of specific dietary components, namely potatoes, beans, dark green vegetables, and fruits, were found to effectively reduce the odds of GMS or related indices during mid-pregnancy.

Gestational Diabetes Mellitus—Recent Literature Review

Gestational diabetes mellitus (GDM), which is defined as a state of hyperglycemia that is first recognized during pregnancy, is currently the most common medical complication in pregnancy. GDM affects approximately 15% of pregnancies worldwide, accounting for approximately 18 million births annually. Mothers with GDM are at risk of developing gestational hypertension, pre-eclampsia and termination of pregnancy via Caesarean section. In addition, GDM increases the risk of complications, including cardiovascular disease, obesity and impaired carbohydrate metabolism, leading to the development of type 2 diabetes (T2DM) in both the mother and infant. The increase in the incidence of GDM also leads to a significant economic burden and deserves greater attention and awareness. A deeper understanding of the risk factors and pathogenesis becomes a necessity, with particular emphasis on the influence of SARS-CoV-2 and diagnostics, as well as an effective treatment, which may reduce perinatal and metabolic complications. The primary treatments for GDM are diet and increased exercise. Insulin, glibenclamide and metformin can be used to intensify the treatment. This paper provides an overview of the latest reports on the epidemiology, pathogenesis, diagnosis and treatment of GDM based on the literature.

Early Identification of the Maternal, Placental and Fetal Dialog in Gestational Diabetes and Its Prevention

Gestational diabetes mellitus (GDM) complicates between 5 and 12% of pregnancies, with associated maternal, fetal, and neonatal complications. The ideal screening and diagnostic criteria to diagnose and treat GDM have not been established and, currently, diagnostic use with an oral glucose tolerance test occurs late in pregnancy and produces poor reproducibility. Therefore, in recent years, significant research has been undertaken to identify a first-trimester biomarker that can predict GDM later in pregnancy, enable early intervention, and reduce GDM-related adverse pregnancy outcomes. Possible biomarkers include glycemic markers (fasting glucose and hemoglobin A1c), adipocyte-derived markers (adiponectin and leptin), pregnancy-related markers (pregnancy-associated plasma protein-A and the placental growth factor), inflammatory markers (C-reactive protein and tumor necrosis factor-α), insulin resistance markers (sex hormone-binding globulin), and others. This review summarizes current data on first-trimester biomarkers, the advantages, and the limitations. Large multi-ethnic clinical trials and cost-effectiveness analyses are needed not only to build effective prediction models but also to validate their clinical use.

Predictive role of altered leptin, adiponectin and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid secretion in gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy, leading to considerable maternal and fetal risks. The main aim of this study was to determine the predictive value of the levels of adiponectin (AN), leptin (L) and CMPF (3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid) in the development of GDM. We conducted a prospective longitudinal study on 68 pregnant women that were not at risk of developing GDM, in whom we determined AN, L, CMPF levels at 11-13 weeks +6 days of pregnancy during the first trimester screening. Twenty-one of all the patients included in the study developed GDM during pregnancy. Oral glucose tolerance test (OGTT)/75 g was performed at 24-28 weeks of gestation. L levels were significantly higher in patients who developed GDM than in those who did not develop diabetes (P<0.001). The AN/L ratio was significantly lower in patients with GDM (P=0.03). AN and CMPF levels were not associated with GDM. The probability of developing gestational diabetes was higher in patients with L levels above the L cut-off value of 16 ng/ml [area under the curve (AUC), 0.775; 95% confidence interval (CI) 0.658-0.867], sensitivity 100% (95% CI 83.9-100), specificity 48.9% (95% CI 34.1-63.9) (P<0.001). Advanced maternal age and higher L levels were found to be predictive factors [odds ratio (OR)=1.16 and OR=1.06, respectively] independently associated with gestational diabetes. In as far as general factors are concerned, the patient BMI (body mass index) at the beginning of the pregnancy and smoking were found to be the main risk factors for the onset of GDM. This study showed that elevated L levels are a strong predictor of GDM, while AN and CMPF levels are not, as they failed to show a significant association.

Exploring the Relationship Between Maternal Circulating Hormones and Gestational Weight Gain in Women Without Obesity: A Cross-Sectional Study

Background

Central homeostatic regulation of fat stores is attenuated during pregnancy, to allow for adequate fat deposition to support fetal development and lactation. What factors particular to pregnancy facilitate fat accumulation, and why gestational weight gain (GWG) is so variable, are not clear. The aim of this cross-sectional study was to examine the associations between GWG and circulating hormones with known effects on appetite and growth.

Methods

Women without obesity (body mass index, BMI <30 kg/m²), with a healthy singleton pregnancy, were recruited at the time of delivery by elective Caesarean section at a tertiary obstetric hospital. Women with preterm (<37 weeks) delivery and smokers were excluded. Maternal blood was collected at the time of delivery for measurement of fasting oestradiol, progesterone, prolactin, insulin, leptin, insulin-like growth factor 1 and insulin-like growth factor binding protein 3. Comparisons were made between women who gained weight within the range recommended by Institute of Medicine guidelines for normal weight women (11.5–16 kg; n=34) and those who gained excessive weight (>16 kg; n=35) during pregnancy. Analysis of covariance was carried out using multiple linear regression to test the effect of GWG group on biochemical parameters, accounting for pre-pregnancy BMI.

Results

The 69 participants had a mean age of 34.6 ± 4.3 years, and pre-pregnancy BMI of (23.3 ± 1.8 kg/m²), with no significant differences between groups in pre-pregnancy weight, BMI, age, birthweight or parity. Mean GWG was 14.0 ± 1.3 kg in the “recommended” group and 19.6 ± 3.2 kg in the “excessive” group. Leptin was significantly higher (43.4 ± 21.6 vs 33.4 ± 15.0 ng/mL, p=0.03) and prolactin tended to be lower (159.5 ± 66.1 vs 194.0 ± 85.6 ng/mL, p=0.07) at delivery in women with excessive (vs recommended) GWG. No other circulating factors were found to differ between groups. The between-group difference in leptin remained after adjustment for pre-pregnancy BMI in multiple linear regression and quantile regression analyses.

Conclusion

In women without obesity, leptin remains a marker of adiposity during pregnancy. GWG was not associated with other circulating hormones with effects on appetite and growth.

Gestational Diabetes Mellitus Treatment Schemes Modify Maternal Plasma Cholesterol Levels Dependent to Women´s Weight: Possible Impact on Feto-Placental Vascular Function

: Gestational diabetes mellitus (GDM) associates with fetal endothelial dysfunction (ED), which occurs independently of adequate glycemic control. Scarce information exists about the impact of different GDM therapeutic schemes on maternal dyslipidemia and obesity and their contribution to the development of fetal-ED. The aim of this study was to evaluate the effect of GDM-treatments on lipid levels in nonobese (N) and obese (O) pregnant women and the effect of maternal cholesterol levels in GDM-associated ED in the umbilical vein (UV). O-GDM women treated with diet showed decreased total cholesterol (TC) and low-density lipoproteins (LDL) levels with respect to N-GDM ones. Moreover, O-GDM women treated with diet in addition to insulin showed higher TC and LDL levels than N-GDM women. The maximum relaxation to calcitonin gene-related peptide of the UV rings was lower in the N-GDM group compared to the N one, and increased maternal levels of TC were associated with even lower dilation in the N-GDM group. We conclude that GDM-treatments modulate the TC and LDL levels depending on maternal weight. Additionally, increased TC levels worsen the GDM-associated ED of UV rings. This study suggests that it could be relevant to consider a specific GDM-treatment according to weight in order to prevent fetal-ED, as well as to consider the possible effects of maternal lipids during pregnancy.

Effect of gestational weight gain on insulin resistance mediated by serum adipokine concentrations in advanced maternal age

INTRODUCTION

With the implementation of the universal two-child policy, the number of pregnant women of advanced maternal age (AMA) will increase steadily. We aimed to investigate whether the effect of gestational weight gain on insulin resistance (IR) before delivery was mediated by serum adipokine concentrations in AMA.

MATERIAL AND METHODS

This cross-sectional study included 80 pregnant women of AMA recruited consecutively before delivery from the Department of Obstetrics and Gynecology between August 2016 and July 2017. At delivery, maternal weight during the third trimester was recorded and serum adipokines were measured. IR was calculated using the homeostasis model assessment 2 (HOMA2) method.

RESULTS

Weight gain (WG) during the third trimester was positively associated with serum leptin concentrations (r = 0.34, p = 0.0018) and HOMA-IR indices (r = 0.25, p = 0.025), but not related with serum concentration of adiponectin (r = 0.12, p = 0.28). WG during the third trimester and serum concentration of leptin were independently associated with the level of HOMA-IR by multivariate analysis. Subsequently, according to mediation analysis, the association between WG during the third trimester and HOMA-IR mediated by serum leptin concentrations was statistically significant (z = 1.588, p < 0.05).

CONCLUSIONS

Taken together, our findings suggest that the relationship between WG during the third trimester and IR was mediated by serum leptin concentrations in AMA, but not serum adiponectin concentrations.

Adipokine levels in overweight women with early-onset gestational diabetes mellitus

PURPOSE

The study of adipokines in overweight women with early-onset (diagnosed before 20 weeks) gestational diabetes mellitus (GDM) could help to understand the ethiopathological mechanisms of this disorder. Our aim was to assess adipokine levels in overweight pregnant women with early-onset GDM compared to patients with standard-onset (diagnosed at 24-28 weeks) GDM and to glucose-tolerant women at the same gestational ages.

METHODS

This nested case-control study included 133 overweight pregnant women: 33 with early-onset (diagnosed < 20 weeks) GDM; 40 with standard-onset (diagnosed ≥ 24 weeks) GDM and 60 glucose-tolerant (normal oral glucose tolerance tests < 20 and ≥ 24 weeks). Adiponectin, leptin, resistin, visfatin and ghrelin serum levels were measured by ELISA.

RESULTS

Adiponectin serum levels were significantly lower in early-onset GDM women than in standard-onset GDM patients or controls matched for gestational age. Leptin serum levels were significantly higher in women with early-onset GDM than in controls. Women with early-onset GDM had lower adiponectin/leptin ratio than those with standard-onset GDM. There were no significant differences in resistin, ghrelin and visfatin serum levels among the participants.

CONCLUSIONS

Our results suggest that, compared to overweight glucose-tolerant women and patients with standard-onset GDM, overweight women with early-onset GDM have unbalanced adipokine levels, suggesting that they have a more inflammatory profile.

The Role of Inflammation in the Development of GDM and the Use of Markers of Inflammation in GDM Screening

Gestational diabetes mellitus is a hyperglycaemic state first recognised in pregnancy. GDM affects both mother and child. Women with GDM and their new-borns are at risk of developing type 2 diabetes in the future. The screening and diagnostic criteria for GDM are inconsistent and thus novel biomarkers of GDM are required to strengthen the screening and diagnostic processes in GDM. Chronic low-grade inflammation is linked to the majority of the well-established risk factors of GDM such as old age, obesity and PCOS. This review provides an overview of the present knowledge on the pathology of GDM, the screening criteria applied, the role of inflammation in the development of GDM and the use of markers of inflammation namely cytokines, oxidative stress markers, lipids, amino acids and iron markers in screening and diagnosis of GDM.

The Pathophysiology of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a serious pregnancy complication, in which women without previously diagnosed diabetes develop chronic hyperglycemia during gestation. In most cases, this hyperglycemia is the result of impaired glucose tolerance due to pancreatic β-cell dysfunction on a background of chronic insulin resistance. Risk factors for GDM include overweight and obesity, advanced maternal age, and a family history or any form of diabetes. Consequences of GDM include increased risk of maternal cardiovascular disease and type 2 diabetes and macrosomia and birth complications in the infant. There is also a longer-term risk of obesity, type 2 diabetes, and cardiovascular disease in the child. GDM affects approximately 16.5% of pregnancies worldwide, and this number is set to increase with the escalating obesity epidemic. While several management strategies exist-including insulin and lifestyle interventions-there is not yet a cure or an efficacious prevention strategy. One reason for this is that the molecular mechanisms underlying GDM are poorly defined. This review discusses what is known about the pathophysiology of GDM, and where there are gaps in the literature that warrant further exploration.

Controversies in Screening and Diagnostic Criteria for Gestational Diabetes in Early and Late Pregnancy

This review serves to evaluate the screening and diagnostic strategies for gestational diabetes and overt diabetes in pregnancy. We focus on the different early screening and diagnostic approaches in first trimester including fasting plasma glucose, random plasma glucose, oral glucose tolerance test, hemoglobin A1c, risk prediction models and biomarkers. Early screening for gestational diabetes is currently not recommended since the potential benefits and harms of early detection and subsequent treatment need to be further evaluated in randomized controlled trials.

Could a remarkable decrease in leptin and insulin levels from colostrum to mature milk contribute to early growth catch-up of SGA infants?

BACKGROUND

Breast milk is known to contain many bioactive hormones and peptides, which can influence infant growth and development. In this context, the purpose of this study was to evaluate the influence of different clinical pregnancy conditions on hormone concentrations in colostrum and mature breast milk.

METHODS

An observational study was performed with mother-newborn pairs divided into five groups according to maternal clinical background: diabetes (12), hypertension (5), smoking (19), intrauterine growth restriction of unknown causes with small-for-gestational-age newborns at delivery (12), and controls (21). Socioeconomic data, anthropometric measurements and breast milk samples were collected between the first 24 and 48 h and 30 days postpartum. Leptin, adiponectin, and insulin levels in breast milk were measured by immunoassays.

RESULTS

A significant decrease in leptin (p = 0.050) and insulin (p = 0.012) levels from colostrum to mature breast milk in mothers of small-for-gestational-age infants was observed. Maternal body mass index was correlated with both leptin and insulin, but not with adiponectin. Insulin levels were negatively correlated to infant weight gain from birth to one month (p = 0.050). In addition, catch-up growth was verified for small-for-gestational-age infants throughout the first month of life.

CONCLUSIONS

This study suggests that a remarkable decrease in leptin and insulin levels in mature milk of mothers of small-for-gestational-age newborns may be involved in the rapid weight gain of these newborns. The physiological and external mechanisms by which these significant decreases and rapid weight gains occur in this group remain to be elucidated.

Adiponectin and leptin as first trimester markers for gestational diabetes mellitus: a cohort study

BACKGROUND

Gestational diabetes mellitus (GDM) is increasing partly due to the obesity epidemic. Adipocytokines have thus been suggested as first trimester screening markers for GDM. In this study we explore the associations between body mass index (BMI) and serum concentrations of adiponectin, leptin, and the adiponectin/leptin ratio. Furthermore, we investigate whether these markers can improve the ability to screen for GDM in the first trimester.

METHODS

A cohort study in which serum adiponectin and leptin were measured between gestational weeks 6+0 and 14+0 in 2590 pregnant women, categorized into normal weight, moderately obese, or severely obese.

RESULTS

Lower concentrations of adiponectin were associated with GDM in all BMI groups; the association was more pronounced in BMI<35 kg/m2 (p=0.30 for interaction). Leptin was inversely associated with GDM in severely obese (p=0.033), but showed no association in women with BMI<35 kg/m2. The adiponectin/leptin ratio was associated with GDM in women with BMI<35 kg/m2 but not in severely obese women (p=0.79). In regard to predicting GDM, maternal characteristics combined with adiponectin alone, adiponcetin and leptin, and adiponcetin/leptin ratio had the strongest associations in women with BMI<35 kg/m2. These models had a detection rate of 77.3%-80.3% when the false positive rate was fixed at 25%.

CONCLUSIONS

Low adiponectin measured in the first trimester is associated with the development of GDM; higher BMI was associated with lower performance of adiponectin, though this was insignificant. Leptin had an inverse relationship with GDM in severely obese women and did not improve the ability to predict GDM.

The Effects of Myo-Inositol and B and D Vitamin Supplementation in the db/+ Mouse Model of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a growing concern, affecting an increasing number of pregnant women worldwide. By predisposing both the affected mothers and children to future disease, GDM contributes to an intergenerational cycle of obesity and diabetes. In order to stop this cycle, safe and effective treatments for GDM are required. This study sought to determine the treatment effects of dietary supplementation with myo-inositol (MI) and vitamins B2, B6, B12, and D in a mouse model of GDM (pregnant db/+ dams). In addition, the individual effects of vitamin B2 were examined. Suboptimal B2 increased body weight and fat deposition, decreased GLUT4 adipose tissue expression, and increased expression of inflammatory markers. MI supplementation reduced weight and fat deposition, and reduced expression of inflammatory markers in adipose tissue of mice on suboptimal B2. MI also significantly reduced the hyperleptinemia observed in db/+ mice, when combined with supplemented B2. MI was generally associated with adipose tissue markers of improved insulin sensitivity and glucose uptake, while the combination of vitamins B2, B6, B12, and D was associated with a reduction in adipose inflammatory marker expression. These results suggest that supplementation with MI and vitamin B2 could be beneficial for the treatment/prevention of GDM.

Early Pregnancy Biochemical Predictors of Gestational Diabetes Mellitus

PURPOSE OF REVIEW

Universal oral glucose tolerance-based screening is employed to identify pregnant women with gestational diabetes mellitus (GDM), as treatment of this condition decreases the risk of associated complications. A simple and accurate blood test which identifies women at low or high risk for GDM in the first trimester would have the potential to decrease costs and improve outcomes through prevention or treatment. This review summarizes published data on early pregnancy biomarkers which have been tested as predictors of GDM.

RECENT FINDINGS

A large number of first-trimester biochemical predictors of GDM have been reported, mostly in small case-control studies. These include glycemic markers (fasting glucose, post-load glucose, hemoglobin A1C), inflammatory markers (C-reactive protein, tumor necrosis factor-alpha), insulin resistance markers (fasting insulin, sex hormone-binding globulin), adipocyte-derived markers (adiponectin, leptin), placenta-derived markers (follistatin-like-3, placental growth factor, placental exosomes), and others (e.g., glycosylated fibronectin, soluble (pro)renin receptor, alanine aminotransferase, ferritin). A few large studies suggest that first-trimester fasting glucose or hemoglobin A1C may be useful for identifying women who would benefit from early GDM treatment. To translate the findings from observational studies of first-trimester biomarkers for GDM to clinical practice, trials or cost-effectiveness analyses of screening and treatment strategies based on these novel biomarkers are needed.

Maternal Hyperleptinemia Is Associated with Male Offspring's Altered Vascular Function and Structure in Mice

Children of mothers with gestational diabetes have greater risk of developing hypertension but little is known about the mechanisms by which this occurs. The objective of this study was to test the hypothesis that high maternal concentrations of leptin during pregnancy, which are present in mothers with gestational diabetes and/or obesity, alter blood pressure, vascular structure and vascular function in offspring. Wildtype (WT) offspring of hyperleptinemic, normoglycemic, Leprdb/+ dams were compared to genotype matched offspring of WT-control dams. Vascular function was assessed in male offspring at 6, and at 31 weeks of age after half the offspring had been fed a high fat, high sucrose diet (HFD) for 6 weeks. Blood pressure was increased by HFD but not affected by maternal hyperleptinemia. On a standard diet, offspring of hyperleptinemic dams had outwardly remodeled mesenteric arteries and an enhanced vasodilatory response to insulin. In offspring of WT but not Leprdb/+ dams, HFD induced vessel hypertrophy and enhanced vasodilatory responses to acetylcholine, while HFD reduced insulin responsiveness in offspring of hyperleptinemic dams. Offspring of hyperleptinemic dams had stiffer arteries regardless of diet. Therefore, while maternal hyperleptinemia was largely beneficial to offspring vascular health under a standard diet, it had detrimental effects in offspring fed HFD. These results suggest that circulating maternal leptin concentrations may interact with other factors in the pre- and post -natal environments to contribute to altered vascular function in offspring of diabetic pregnancies.

ENDOCRINOLOGY OF PREGNANCY: Gestational diabetes mellitus: definition, aetiological and clinical aspects

Gestational diabetes (GDM) is defined as a glucose intolerance resulting in hyperglycaemia of variable severity with onset during pregnancy. This review aims to revisit the pathogenesis and aetiology of GDM in order to better understand its clinical presentation and outcomes. During normal pregnancy, insulin sensitivity declines with advancing gestation. These modifications are due to placental factors, progesterone and estrogen. In a physiological situation, a compensatory increase in insulin secretion maintains a normal glucose homeostasis. GDM occurs if pancreatic β-cells are unable to face the increased insulin demand during pregnancy. GDM is most commonly a forerunner of type 2 diabetes (T2D) - the most prevalent form of diabetes. These women share similar characteristics with predisposed subjects to T2D: insulin resistance before and after pregnancy, and carry more T2D risk alleles. Auto-immune and monogenic diabetes are more rare aetiologies of GDM. Adverse pregnancy outcomes of GDM are mainly related to macrosomia caused by fetal hyperinsulinism in response to high glucose levels coming from maternal hyperglycaemia. Screening recommendations and diagnosis criteria of GDM have been recently updated. High risk patients should be screened as early as possible using fasting plasma glucose, and if normal, at 24-28 weeks of gestation using 75 g oral glucose tolerance test. The treatment of GDM is based on education with trained nurses and dieticians, and if necessary insulin therapy.

Hyperleptinemia During Pregnancy Decreases Adult Weight of Offspring and Is Associated With Increased Offspring Locomotor Activity in Mice

Pregnant women who are obese or have gestational diabetes mellitus have elevated leptin levels and their children have an increased risk for child and adult obesity. The goals of this study were to determine whether offspring weights are altered by maternal hyperleptinemia, and whether this occurs via behavioral changes that influence energy balance. We used 2 hyperleptinemic mouse models. The first was females heterozygous for a leptin receptor mutation (DB/+), which were severely hyperleptinemic, and that were compared with wild-type females. The second model was wild-type females infused with leptin (LEP), which were moderately hyperleptinemic, and were compared with wild-type females infused with saline (SAL). Total food consumption, food preference, locomotor activity, coordinated motor skills, and anxiety-like behaviors were assessed in wild-type offspring from each maternal group at 3 postnatal ages: 4-6, 11-13, and 19-21 weeks. Half the offspring from each group were then placed on a high-fat diet, and behaviors were reassessed. Adult offspring from both groups of hyperleptinemic dams weighed less than their respective controls beginning at 23 weeks of age, independent of diet or sex. Weight differences were not explained by food consumption or preference, because female offspring from hyperleptinemic dams tended to consume more food and had reduced preference for palatable, high-fat and sugar, food compared with controls. Offspring from DB/+ dams were more active than offspring of controls, as were female offspring of LEP dams. Maternal hyperleptinemia during pregnancy did not predispose offspring to obesity, and in fact, reduced weight gain.

Maternal body mass index during early pregnancy, gestational weight gain, and risk of autism spectrum disorders: Results from a Swedish total population and discordant sibling study

BACKGROUND

Prenatal environmental factors such as maternal adiposity may influence the risk of offspring autism spectrum disorders (ASD), though current evidence is inconsistent. The objective of this study was to assess the relationship of parental BMI and gestational weight gain (GWG) with risk of offspring ASD in a population-based cohort study using family-based study designs.

METHODS

The cohort was based in Stockholm County, Sweden, including 333,057 individuals born 1984-2007, of whom 6420 were diagnosed with an ASD. We evaluated maternal body mass index (BMI) at first antenatal visit, GWG and paternal BMI at the time of conscription into the Swedish military as exposures using general estimating equation (GEE) models with logit link.

RESULTS

At the population level, maternal overweight/obesity was associated with increased risk of offspring ASD [odds ratio (OR)25 ≤ BMI < 30 1.31, 95% confidence interval = 1.21-1.41; ORBMI ≥ 30 1.94, 1.72-2.17], as was paternal underweight (ORBMI < 18.5, 1.19, 1.06-1.33) and obesity (ORBMI ≥ 30 1.47, 1.12-1.92) in mutually adjusted models. However, in matched sibling analyses, the relationship between elevated maternal BMI and ASD risk was not apparent. GWG had a U-shaped association with offspring ASD at the population level (ORinsufficient 1.22, 1.07-1.40; ORexcessive 1.23, 1.08-1.40). Matched sibling analyses were suggestive of elevated risk with excessive GWG (ORinsufficient 1.12, 0.68-1.84; ORexcessive 1.48, 0.93-2.38).

CONCLUSIONS

Whereas population-level results suggested that maternal BMI was associated with ASD, sibling analyses and paternal BMI analyses indicate that maternal BMI may also be a proxy marker for other familial risk factors. Evidence is stronger for a direct link between GWG and ASD risk.

Patterns of gestational weight gain related to fetal growth among women with overweight and obesity

OBJECTIVE

Maternal obesity is associated with increased risk of large-for-gestational-age (LGA) and small-for-gestational-age (SGA) births. Both are related to childhood obesity. This study considers that the patterns of gestational weight gain (GWG) may help to disentangle these competing risks.

METHODS

Patterns of GWG were characterized among a cohort of women with overweight or obesity (n = 651). Polytomous logistic regression models were tested for associations between GWG patterns and birth weight outcomes: SGA (<10th) and LGA (>90th percentile).

RESULTS

Rates of SGA were higher than those for LGA (14.9% vs. 7.8%). Four GWG patterns were identified: consistently high (29%), early adequate/late high (33%), consistently adequate (18%), and consistently low (20%). Risk of LGA was highest in women with consistently high GWG (adjusted odds ratio [OR] 4.62 [1.53, 13.96]), and risk was elevated, but with lower magnitude, among women with early adequate/late high gains (OR 3.07 [1.01, 9.37]). High GWG before 20 weeks, regardless of later gain, was related to LGA. Low gain before 20 weeks accompanied by high gain later may be associated with reduced SGA risk (0.55 [0.29, 1.07]).

CONCLUSIONS

The pattern of weight gain during pregnancy may be an important contributor to or marker of abnormal fetal growth among women with overweight or obesity.

Fetal sex and maternal risk of gestational diabetes mellitus: the impact of having a boy

OBJECTIVE

Retrospective analyses of perinatal databases have raised the intriguing possibility of an increased risk of gestational diabetes mellitus (GDM) in women carrying a male fetus, but it has been unclear if this was a spurious association. We thus sought to evaluate the relationship between fetal sex and maternal glucose metabolism in a well-characterized cohort of women reflecting the full spectrum of gestational glucose tolerance from normal to mildly abnormal to GDM.

RESEARCH DESIGN AND METHODS

A total of 1,074 pregnant women underwent metabolic characterization, including oral glucose tolerance test (OGTT), at mean 29.5 weeks' gestation. The prevalence of GDM, its pathophysiologic determinants (β-cell function and insulin sensitivity/resistance), and its clinical risk factors were compared between women carrying a female fetus (n = 534) and those carrying a male fetus (n = 540).

RESULTS

Women carrying a male fetus had lower mean adjusted β-cell function (insulinogenic index divided by HOMA of insulin resistance: 9.4 vs. 10.5, P = 0.007) and higher mean adjusted blood glucose at 30 min (P = 0.025), 1 h (P = 0.004), and 2 h (P = 0.02) during the OGTT, as compared with those carrying a female fetus. Furthermore, women carrying a male fetus had higher odds of developing GDM (odds ratio 1.39 [95% CI 1.01-1.90]). Indeed, male fetus further increased the relative risk of GDM conferred by the classic risk factors of maternal age >35 years and nonwhite ethnicity by 47 and 51%, respectively.

CONCLUSIONS

Male fetus is associated with poorer β-cell function, higher postprandial glycemia, and an increased risk of GDM in the mother. Thus, fetal sex potentially may influence maternal glucose metabolism in pregnancy.

Maternal lipid levels during pregnancy and gestational diabetes: a systematic review and meta-analysis

BACKGROUND

Lipid levels during pregnancy in women with gestational diabetes mellitus (GDM) have been extensively studied; however, it remains unclear whether dyslipidaemia is a potential marker of preexisting insulin resistance.

OBJECTIVE

To evaluate the relationship between lipid measures throughout pregnancy and GDM.

SEARCH STRATEGY

We searched PubMed-MedLine and SCOPUS (inception until January 2014) and reference lists of relevant studies.

SELECTION CRITERIA

Publications describing original data with at least one raw lipid (total cholesterol, high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], or triglyceride) measurement during pregnancy in women with GDM and healthy pregnant controls were retained.

DATA COLLECTION AND ANALYSIS

Data extracted from 60 studies were pooled and weighted mean difference (WMD) in lipid levels was calculated using random effects models. Meta-regression was also performed to identify sources of heterogeneity.

MAIN RESULTS

Triglyceride levels were significantly elevated in women with GDM compared with those without GDM (WMD 30.9, 95% confidence interval [95% CI] 25.4-36.4). This finding was consistent in the first, second and third trimesters of pregnancy. HDL-C levels were significantly lower in women with GDM compared with those without GDM in the second (WMD -4.6, 95% CI -6.2 to -3.1) and third (WMD -4.1, 95% CI -6.5 to -1.7) trimesters of pregnancy. There were no differences in aggregate total cholesterol or LDL-C levels between women with GDM and those without insulin resistance.

AUTHOR'S CONCLUSIONS

Our meta-analysis shows that triglycerides are significantly elevated among women with GDM compared with women without insulin resistance and this finding persists across all three trimesters of pregnancy.

Adipokines in gestational diabetes

Gestational diabetes is characterised by glucose intolerance with onset or first recognition during pregnancy. The disease shows facets of the metabolic syndrome including obesity, insulin resistance, and dyslipidaemia. Adipokines are a group of proteins secreted from adipocytes, which are dysregulated in obesity and contribute to metabolic and vascular complications. Recent studies have assessed the role of various adipokines including leptin, adiponectin, tumour necrosis factor α (TNFα), adipocyte fatty acid-binding protein (AFABP), retinol-binding protein 4 (RBP4), resistin, NAMPT, SERPINA12, chemerin, progranulin, FGF-21, TIMP1, LCN2, AZGP1, apelin (APLN), and omentin in gestational diabetes. This Review provides an overview of these key adipokines, their regulation in, and potential contribution to gestational diabetes. Based on the evidence so far, the adipokines adiponectin, leptin, TNFα, and AFABP seem to be the most probable candidates involved in the pathophysiology of gestational diabetes.