The chromosome 3q25 genomic region is associated with measures of adiposity in newborns in a multi-ethnic genome-wide association study

Newborns characterized as large and small for gestational age are at risk for increased mortality and morbidity during the first year of life as well as for obesity and dysglycemia as children and adults. The intrauterine environment and fetal genes contribute to the fetal size at birth. To define the genetic architecture underlying the newborn size, we performed a genome-wide association study (GWAS) in 4281 newborns in four ethnic groups from the Hyperglycemia and Adverse Pregnancy Outcome Study. We tested for association with newborn anthropometric traits (birth length, head circumference, birth weight, percent fat mass and sum of skinfolds) and newborn metabolic traits (cord glucose and C-peptide) under three models. Model 1 adjusted for field center, ancestry, neonatal gender, gestational age at delivery, parity, maternal age at oral glucose tolerance test (OGTT); Model 2 adjusted for Model 1 covariates, maternal body mass index (BMI) at OGTT, maternal height at OGTT, maternal mean arterial pressure at OGTT, maternal smoking and drinking; Model 3 adjusted for Model 2 covariates, maternal glucose and C-peptide at OGTT. Strong evidence for association was observed with measures of newborn adiposity (sum of skinfolds model 3 Z-score 7.356, P = 1.90×10⁻¹³, and to a lesser degree fat mass and birth weight) and a region on Chr3q25.31 mapping between CCNL and LEKR1. These findings were replicated in an independent cohort of 2296 newborns. This region has previously been shown to be associated with birth weight in Europeans. The current study suggests that association of this locus with birth weight is secondary to an effect on fat as opposed to lean body mass.

Maternal obesity and vitamin D sufficiency are associated with cord blood vitamin D insufficiency

CONTEXT

An inverse relationship between total serum 25-hydroxyvitamin D (25-OH D) and increased adiposity has been established in children, adolescents, and adults. However, the relationship between neonatal adiposity and vitamin D status has not been reported. Both maternal obesity and vitamin D deficiency in pregnancy are common and are associated with adverse pregnancy outcomes.

OBJECTIVE

The aim of the study was to determine the relationship between vitamin D levels in mothers and newborns, as influenced by maternal obesity, and evaluate these associations with neonatal adiposity.

DESIGN, SETTING, AND PATIENTS

Sixty-one maternal-neonatal pairs participated in this cross-sectional study at an academic medical center. Mothers had a prepregnancy body mass index that was normal or obese.

OUTCOME MEASURES

Maternal and cord blood sera were assayed for 25-OH D, and neonatal body composition was measured by air displacement plethysmography.

RESULTS

Mothers had similar and sufficient levels of 25-OH D when measured at 36-38 wk gestation, irrespective of body mass index category (normal weight, 46.05, vs. obese, 49.84 ng/ml; P = not significant). However, cord blood 25-OH D was higher in neonates of normal-weight mothers compared to neonates of obese mothers (27.45 vs. 20.81 ng/ml; P = 0.02). The variance in cord blood 25-OH D was explained by four factors: maternal 25-OH D level, the presence of maternal obesity, maternal age, and neonatal adiposity (r(2) = 0.66).

CONCLUSION

Obese women transfer less 25-OH D to offspring than normal-weight women, despite similar serum levels. Cord blood 25-OH D levels directly correlate to neonatal percentage body fat. These novel findings underscore the evolving relationships between maternal obesity, vitamin D nutritional status, and adiposity in the neonatal period that may influence subsequent childhood and adulthood vitamin D-dependent processes.

The diagnosis of gestational diabetes mellitus: new paradigms or status quo?

The Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study showed significant perinatal risks at levels of maternal hyperglycemia below values that are diagnostic for diabetes. A Consensus Panel of the International Association of Diabetes and Pregnancy Study Groups (IADPSG) reviewed HAPO Study results and other work that examined associations of maternal glycemia with perinatal and long-term outcomes in offspring and published recommendations for diagnosis and classification of hyperglycemia in pregnancy in 2010. Subsequently, some commentaries and debate challenged the IADPSG recommendations. In this review, we provide details regarding some points that were considered by the IADPSG Consensus Panel but not published and address the following issues: 1) what should be the frequency of gestational diabetes mellitus (GDM); 2) were appropriate outcomes and odds ratios used to define diagnostic thresholds for GDM; 3) to improve perinatal outcome, should the focus be on GDM, obesity, or both; 4) should results of randomized controlled trials of treatment of mild GDM influence recommendations for diagnostic thresholds; and, 5) other issues related to diagnosis of GDM. Other groups are independently considering strategies for the diagnosis of GDM. However, after careful consideration of these issues, we affirm our support for the recommendations of the IADPSG Consensus Panel.

The hyperglycemia and adverse pregnancy outcome study: associations of GDM and obesity with pregnancy outcomes

OBJECTIVE

To determine associations of gestational diabetes mellitus (GDM) and obesity with adverse pregnancy outcomes in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study.

RESEARCH DESIGN AND METHODS

Participants underwent a 75-g oral glucose tolerance test (OGTT) between 24 and 32 weeks. GDM was diagnosed post hoc using International Association of Diabetes and Pregnancy Study Groups criteria. Neonatal anthropometrics and cord serum C-peptide were measured. Adverse pregnancy outcomes included birth weight, newborn percent body fat, and cord C-peptide >90th percentiles, primary cesarean delivery, preeclampsia, and shoulder dystocia/birth injury. BMI was determined at the OGTT. Multiple logistic regression was used to examine associations of GDM and obesity with outcomes.

RESULTS

Mean maternal BMI was 27.7, 13.7% were obese (BMI ≥33.0 kg/m(2)), and GDM was diagnosed in 16.1%. Relative to non-GDM and nonobese women, odds ratio for birth weight >90th percentile for GDM alone was 2.19 (1.93-2.47), for obesity alone 1.73 (1.50-2.00), and for both GDM and obesity 3.62 (3.04-4.32). Results for primary cesarean delivery and preeclampsia and for cord C-peptide and newborn percent body fat >90th percentiles were similar. Odds for birth weight >90th percentile were progressively greater with both higher OGTT glucose and higher maternal BMI. There was a 339-g difference in birth weight for babies of obese GDM women, compared with babies of normal/underweight women (64.2% of all women) with normal glucose based on a composite OGTT measure of fasting plasma glucose and 1- and 2-h plasma glucose values (61.8% of all women).

CONCLUSIONS

Both maternal GDM and obesity are independently associated with adverse pregnancy outcomes. Their combination has a greater impact than either one alone.

The role of inflammatory pathway genetic variation on maternal metabolic phenotypes during pregnancy

Background

Since mediators of inflammation are associated with insulin resistance, and the risk of developing diabetes mellitus and gestational diabetes, we hypothesized that genetic variation in members of the inflammatory gene pathway impact glucose levels and related phenotypes in pregnancy. We evaluated this hypothesis by testing for association between genetic variants in 31 inflammatory pathway genes in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) cohort, a large multiethnic multicenter study designed to address the impact of glycemia less than overt diabetes on pregnancy outcome.

Results

Fasting, 1-hour, and 2-hour glucose, fasting and 1-hour C-peptide, and HbA1c levels were measured in blood samples obtained from HAPO participants during an oral glucose tolerance test at 24-32 weeks gestation. We tested for association between 458 SNPs mapping to 31 genes in the inflammatory pathway and metabolic phenotypes in 3836 European ancestry and 1713 Thai pregnant women. The strongest evidence for association was observed with TNF alpha and HbA1c (rs1052248; 0.04% increase per allele C; p-value = 4.4×10⁻⁵), RETN and fasting plasma glucose (rs1423096; 0.7 mg/dl decrease per allele A; p-value = 1.1×10⁻⁴), IL8 and 1 hr plasma glucose (rs2886920; 2.6 mg/dl decrease per allele T; p-value = 1.3×10⁻⁴), ADIPOR2 and fasting C-peptide (rs2041139; 0.55 ug/L decrease per allele A; p-value = 1.4×10⁻⁴), LEPR and 1-hour C-peptide (rs1171278; 0.62 ug/L decrease per allele T; p-value = 2.4×10⁻⁴), and IL6 and 1-hour plasma glucose (rs6954897; −2.29 mg/dl decrease per allele G, p-value = 4.3×10⁻⁴).

Conclusions

Based on the genes surveyed in this study the inflammatory pathway is unlikely to have a strong impact on maternal metabolic phenotypes in pregnancy although variation in individual members of the pathway (e.g. RETN, IL8, ADIPOR2, LEPR, IL6, and TNF alpha,) may contribute to metabolic phenotypes in pregnant women.

Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study: associations of maternal A1C and glucose with pregnancy outcomes

OBJECTIVE

To compare associations of maternal glucose and A1C with adverse outcomes in the multinational Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study and determine, based on those comparisons, if A1C measurement can provide an alternative to an oral glucose tolerance test (OGTT) in pregnant women.

RESEARCH DESIGN AND METHODS

Eligible pregnant women underwent a 75-g OGTT at 24-32 weeks' gestation. A sample for A1C was also collected. Neonatal anthropometrics and cord serum C-peptide were measured. Associations with outcomes were assessed using multiple logistic regression with adjustment for potential confounders.

RESULTS

Among 23,316 HAPO Study participants with glucose levels blinded to caregivers, 21,064 had a nonvariant A1C result. The mean ± SD A1C was 4.79 ± 0.40%. Associations were significantly stronger with glucose measures than with A1C for birth weight, sum of skinfolds, and percent body fat >90th percentile and for fasting and 1-h glucose for cord C-peptide (all P < 0.01). For example, in fully adjusted models, odds ratios (ORs) for birth weight >90th percentile for each measure higher by 1 SD were 1.39, 1.45, and 1.38, respectively, for fasting, 1-, and 2-h plasma glucose and 1.15 for A1C. ORs for cord C-peptide >90th percentile were 1.56, 1.45, and 1.35 for glucose, respectively, and 1.32 for A1C. ORs were similar for glucose and A1C for primary cesarean section, preeclampsia, and preterm delivery.

CONCLUSIONS

On the basis of associations with adverse outcomes, these findings suggest that A1C measurement is not a useful alternative to an OGTT in pregnant women.

Frequency of gestational diabetes mellitus at collaborating centers based on IADPSG consensus panel-recommended criteria: the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study

OBJECTIVE

To report frequencies of gestational diabetes mellitus (GDM) among the 15 centers that participated in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study using the new International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria.

RESEARCH DESIGN AND METHODS

All participants underwent a 75-g oral glucose tolerance test between 24 and 32 weeks' gestation. GDM was retrospectively classified using the IADPSG criteria (one or more fasting, 1-h, or 2-h plasma glucose concentrations equal to or greater than threshold values of 5.1, 10.0, or 8.5 mmol/L, respectively).

RESULTS

Overall frequency of GDM was 17.8% (range 9.3-25.5%). There was substantial center-to-center variation in which glucose measures met diagnostic thresholds.

CONCLUSIONS

Although the new diagnostic criteria for GDM apply globally, center-to-center differences occur in GDM frequency and relative diagnostic importance of fasting, 1-h, and 2-h glucose levels. This may impact strategies used for the diagnosis of GDM.

Executive Summary: Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Multiple laboratory tests are used in the diagnosis and management of patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory analysis in patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. A draft of the guidelines was posted on the Internet, and the document was modified in response to comments. The guidelines were reviewed by the joint Evidence-Based Laboratory Medicine Committee of the AACC and the National Academy of Clinical Biochemistry and were accepted after revisions by the Professional Practice Committee and subsequent approval by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to the long-standing criteria based on measurement of venous plasma glucose, diabetes can be diagnosed by demonstrating increased hemoglobin A1c (Hb A1c) concentrations in the blood. Monitoring of glycemic control is performed by the patients measuring their own plasma or blood glucose with meters and by laboratory analysis of Hb A1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Position statement executive summary: guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus

BACKGROUND

Multiple laboratory tests are used in the diagnosis and management of patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory analysis in patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. A draft of the guidelines was posted on the Internet, and the document was modified in response to comments. The guidelines were reviewed by the joint Evidence-Based Laboratory Medicine Committee of the AACC and the National Academy of Clinical Biochemistry and were accepted after revisions by the Professional Practice Committee and subsequent approval by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to the long-standing criteria based on measurement of venous plasma glucose, diabetes can be diagnosed by demonstrating increased hemoglobin A(1c) (HbA(1c)) concentrations in the blood. Monitoring of glycemic control is performed by the patients measuring their own plasma or blood glucose with meters and by laboratory analysis of HbA(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus

BACKGROUND

Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence-Based Laboratory Medicine Committee of the American Association for Clinical Chemistry jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A(1c) (HbA(1c)) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of HbA(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended.

Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus

BACKGROUND

Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence Based Laboratory Medicine Committee of the AACC jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A(1c) (Hb A(1c)) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of Hb A(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended.

Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus

BACKGROUND

Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence Based Laboratory Medicine Committee of the AACC jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A(1c) (Hb A(1c)) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of Hb A(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended.

Ethnic variation in allele distribution of the androgen receptor (AR) (CAG)n repeat

The androgen receptor (AR) is important in reproductive organ development, as well as tissue homeostasis of the pancreas, liver, and skeletal muscle in adulthood. The trinucleotide (CAG)(n) repeat polymorphism in exon 1 of the AR gene is thought to regulate AR activity, with longer alleles conferring reduced receptor activity. Therefore, the evaluation of the allelic distribution of the AR (CAG)(n) repeat in various ethnic groups is crucial in understanding the interindividual variability in AR activity. We evaluated ethnic variation of this AR polymorphism by genotyping individuals from the multiethnic Hyperglycemia and Adverse Pregnancy Outcome study cohort. We genotyped 4421 Caucasian mothers and 3365 offspring of European ancestry; 1494 Thai mothers and 1742 offspring; 1119 Afro-Caribbean mothers and 1142 offspring; and 780 Hispanic mothers and 770 offspring of Mexican ancestry from Bellflower, California. The distributions of (CAG)(n) alleles among all 4 ethnic groups are significantly different (P < .0001). Pairwise tests confirmed significant differences between each pair of ethnicities tested (P < 10(-28)). The relative AR (CAG)(n) repeat length in the different groups was as follows: Afro-Caribbean (shortest repeat lengths and greatest predicted AR activity) < Caucasian < Hispanic < Thai (longest repeat length and lowest predicted AR activity). Significant interethnic differences in the allele frequencies of the AR exon 1 (CAG)(n) polymorphism exist. Our results suggest that there may be potential ethnic differences in androgenic pathway activity and androgen sensitivity.

Inflammatory mediators and glucose in pregnancy: results from a subset of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study

CONTEXT

Inflammatory mediators are associated with type 2 and gestational diabetes. It is unknown whether there are associations with glucose in pregnant women with lesser degrees of hyperglycemia.

OBJECTIVE

The objective of the study was to examine associations of inflammatory mediators with maternal glucose levels and neonatal size in a subset of participants in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study.

DESIGN

Eligible pregnant women underwent a 75-g oral glucose tolerance test between 24 and 32 wk gestation, and levels of C-peptide, adiponectin, plasminogen activator inhibitor type 1 (PAI-1), C-reactive protein (CRP), and resistin were measured in fasting serum samples. Associations of inflammatory mediators with maternal glucose and with birth size were assessed using multiple linear regression analyses, adjusting for maternal body mass index (BMI), fasting C-peptide, and other potential confounders.

RESULTS

Mean levels of adiponectin declined, and PAI-1 and CRP increased across increasing levels of maternal glucose, BMI, and C-peptide. For example, for fasting plasma glucose less than 75 mg/dl and fasting plasma glucose of 90 mg/dl or greater, adiponectin was 22.5 and 17.4 μg/ml and PAI-1 was 30.9 and 34.2 ng/ml, respectively. Associations with 1- and 2-h plasma glucose remained significant for adiponectin (P<0.001), PAI-1 (P<0.05), and CRP (P<0.01) after adjustment for BMI and C-peptide. Adiponectin and CRP were inversely associated with birth weight, sum of skinfolds and percent body fat, and PAI-1 with sum of skinfolds (all P<0.05) after adjustment for confounders. Resistin was not associated with 1- or 2-h glucose or birth size.

CONCLUSION

Levels of inflammatory mediators are associated with levels of maternal glucose in pregnant women without overt diabetes.

Hyperglycemia and adverse pregnancy outcome study: neonatal glycemia

OBJECTIVE

The goal was to describe the temporal pattern of neonatal plasma glucose levels and associations with maternal glucose levels, cord serum C-peptide levels, and neonatal size and adiposity.

METHODS

A total of 17,094 mothers and infants were included in the Hyperglycemia and Adverse Pregnancy Outcome Study (15 centers in 9 countries). Mothers underwent a 75-g, 2-hour, oral glucose tolerance test (OGTT) at 24 to 32 weeks of gestation. Cord blood and neonatal blood samples were collected. Biochemical neonatal hypoglycemia was defined as glucose levels of <10th percentile (2.2 mmol/L). Clinically identified hypoglycemia was ascertained through medical record review and associations were assessed.

RESULTS

Plasma glucose concentrations were stable during the first 5 hours after birth. Maternal glucose levels were weakly positively associated with biochemical neonatal hypoglycemia (odds ratios: 1.07-1.14 for 1-SD higher OGTT glucose levels). Frequency of neonatal hypoglycemia was higher with higher cord C-peptide levels (odds ratio: 11.6 for highest versus lowest C-peptide category). Larger and/or fatter infants were more likely to have hypoglycemia (P < .001), and infants with hypoglycemia tended to have a higher frequency of cord C-peptide levels of >90th percentile.

CONCLUSIONS

Mean neonatal plasma glucose concentrations varied little in the first 5 hours after birth, which suggests normal postnatal adjustment. Biochemical and clinical hypoglycemia were weakly related to maternal OGTT glucose measurements but were strongly associated with elevated cord serum C-peptide levels. Larger and/or fatter infants were more likely to develop hypoglycemia and hyperinsulinemia. These relationships suggest physiologic relationships between maternal glycemia and fetal insulin production.

Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study: common genetic variants in GCK and TCF7L2 are associated with fasting and postchallenge glucose levels in pregnancy and with the new consensus definition of gestational diabetes mellitus from the International Association of Diabetes and Pregnancy Study Groups

OBJECTIVE

Common genetic variants in GCK and TCF7L2 are associated with higher fasting glucose and type 2 diabetes in nonpregnant populations. However, their associations with glucose levels from oral glucose tolerance tests (OGTTs) in pregnancy have not been assessed in a large sample. We hypothesized that these variants are associated with quantitative measures of glycemia in pregnancy.

RESEARCH DESIGN AND METHODS

We analyzed the associations between variants rs1799884 (GCK) and rs7903146 (TCF7L2) and OGTT outcomes at 24-32 weeks' gestation in 3,811 mothers of European (U.K. and Australia) and 1,706 mothers of Asian (Thailand) ancestry from the HAPO cohort. We also tested associations with offspring birth anthropometrics.

RESULTS

The maternal GCK variant was associated with higher fasting glucose in Europeans (P = 0.001) and Thais (P < 0.0001), 1-h glucose in Europeans (P = 0.001), and 2-h glucose in Thais (P = 0.005). It was also associated with higher European offspring birth weight, fat mass, and skinfold thicknesses (P < 0.05). The TCF7L2 variant was associated with all three maternal glucose outcomes (P = 0.03, P < 0.0001, and P < 0.0001 for fasting and 1-h and 2-h glucose, respectively) in the Europeans but not in the Thais (P > 0.05). In both populations, both variants were associated with higher odds of gestational diabetes mellitus according to the new International Association of Diabetes and Pregnancy Study Groups recommendations (P = 0.001-0.08).

CONCLUSIONS

Maternal GCK and TCF7L2 variants are associated with glucose levels known to carry an increased risk of adverse pregnancy outcome in women without overt diabetes. Further studies will be important to determine the variance in maternal glucose explained by all known genetic variants.

The role of the polycystic ovary syndrome susceptibility locus D19S884 allele 8 in maternal glycemia and fetal size

CONTEXT

The high incidence of insulin resistance, type 2 diabetes, and metabolic syndrome in Western societies and their impact on quality of life emphasize the importance of identifying underlying susceptibility loci for metabolic diseases. The polycystic ovary syndrome (PCOS) susceptibility locus D19S884 allele 8 (A8) is associated with measures of insulin resistance, beta-cell dysfunction, and other metabolic phenotypes in PCOS families. We now investigate the role of D19S884 A8 in pregnancy.

OBJECTIVE

Using the multiethnic Hyperglycemia and Adverse Pregnancy Outcome cohort, we assessed the associations of D19S884 A8 with measures of maternal glycemia and fetal size.

DESIGN

We tested for association of maternal D19S884 A8 with maternal outcomes (fasting, 1-h, and 2-h plasma glucose, and fasting and 1-h C-peptide from an oral glucose tolerance test) and fetal and maternal D19S884 A8 with fetal outcomes (birth weight, length, head circumference, sum of skin folds, fat mass, cord C-peptide, and 2-h neonatal plasma glucose).

SUBJECTS

We analyzed 4424 Caucasian mothers and 3347 offspring of northern European ancestry, 1957 Thai mothers and 2089 offspring from Bangkok, 1208 Afro-Caribbean mothers and 1209 offspring from Barbados, and 774 Hispanic mothers and 762 offspring from Bellflower, California.

RESULTS

After adjusting for confounding variables and multiple testing, neither maternal nor fetal D19S884 A8 showed significant evidence for association with any of the outcomes tested.

CONCLUSIONS

The PCOS susceptibility locus, D19S884 A8, is not a major factor contributing to glycemia during pregnancy or fetal size in a general obstetric population.

Establishing diagnosis of gestational diabetes mellitus: Impact of the hyperglycemia and adverse pregnancy outcome study

The diagnosis of gestational diabetes mellitus (GDM) remains controversial, without universal acceptance of a particular set of diagnostic criteria, and, in fact, a lack of consensus as to whether this is an entity worth diagnosis. Some of the debate derives from differences of opinion about what degree of glucose intolerance should be labeled as GDM. Therefore, it is to be expected that there are different viewpoints on how to detect and screen for GDM. It is believed that early diagnosis will result in a significant improvement in perinatal outcome in these patients. In this review, we discuss the current data concerning screening for GDM and new strategies for GDM diagnosis in light of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study.

Prevention of diabetes in women with a history of gestational diabetes: effects of metformin and lifestyle interventions

CONTEXT

A past history of gestational diabetes mellitus (GDM) confers a very high risk of postpartum development of diabetes, particularly type 2 diabetes.

OBJECTIVE

The Diabetes Prevention Program (DPP) sought to identify individuals with impaired glucose tolerance (IGT) and intervene in an effort to prevent or delay their progression to diabetes. This analysis examined the differences between women enrolled in DPP with and without a reported history of GDM.

DESIGN

The DPP was a randomized, controlled clinical trial.

SETTING

The study was a multicenter, National Institutes of Health-sponsored trial carried out at 27 centers including academic and Indian Health Services sites.

PATIENTS

A total of 2190 women were randomized into the DPP and provided information for past history of GDM. This analysis addressed the differences between those 350 women providing a past history of GDM and those 1416 women with a previous live birth but no history of GDM.

INTERVENTIONS

Subjects were randomized to either standard lifestyle and placebo or metformin therapy or to an intensive lifestyle intervention.

MAIN OUTCOMES

The primary outcome was the time to development of diabetes ascertained by semiannual fasting plasma glucose and annual oral glucose tolerance testing. Assessments of insulin secretion and insulin sensitivity were also performed.

RESULTS

Whereas entering the study with similar glucose levels, women with a history of GDM randomized to placebo had a crude incidence rate of diabetes 71% higher than that of women without such a history. Among women reporting a history of GDM, both intensive lifestyle and metformin therapy reduced the incidence of diabetes by approximately 50% compared with the placebo group, whereas this reduction was 49 and 14%, respectively in parous women without GDM. These data suggest that metformin may be more effective in women with a GDM history as compared with those without.

CONCLUSIONS

Progression to diabetes is more common in women with a history of GDM compared with those without GDM history despite equivalent degrees of IGT at baseline. Both intensive lifestyle and metformin are highly effective in delaying or preventing diabetes in women with IGT and a history of GDM.

Subsequent pregnancy after gestational diabetes mellitus: frequency and risk factors for recurrence in Korean women

OBJECTIVE

The purpose of this study was to determine the frequency of recurrent gestational diabetes mellitus (GDM) and to find risk factors that can predict the recurrence of GDM in Korean women with previous GDM.

RESEARCH DESIGN AND METHODS

We evaluated women who had GDM in an index pregnancy (1993-2001) and a subsequent pregnancy by 2003. An oral glucose tolerance test (OGTT) was performed during the index pregnancy and 2 months postpartum. The recurrence rate of GDM was assessed among 111 women who had a subsequent pregnancy. Multivariate logistic regression analysis was used to identify independent predictors of recurrent GDM.

RESULTS

The frequency of recurrent GDM in subsequent pregnancies was 45.0% (95% CI 35.6-54.4%). Women with impaired fasting glucose and/or impaired glucose tolerance 2 months postpartum were at increased risk for recurrent GDM (relative risk 2.31, 95% CI 1.24-4.30). Higher BMI before the subsequent pregnancy (P = 0.024), higher fasting glucose concentration (P = 0.007) 2 months postpartum, and lower 1-h insulin concentration (P = 0.004) of the diagnostic OGTT in the index pregnancy were independent risk factors for recurrence of GDM in subsequent pregnancies.

CONCLUSIONS

GDM recurred in nearly half of subsequent pregnancies in Korean women. Fasting glucose 2 months postpartum might be a clinically valuable predictor of recurrent GDM risk.