Modestly elevated glucose levels during pregnancy are associated with a higher risk of future diabetes among women without gestational diabetes mellitus

The Glucose Challenge Test in Pregnancy Identifies Future Risk of Diabetes

CONTEXT

Women with gestational diabetes (GDM) have an increased future risk of type 2 diabetes but, in practice, their recommended postpartum glucose tolerance testing is often missed or substituted with measurement of A1c instead.

OBJECTIVE

We hypothesized that the antenatal screening glucose challenge test (GCT) should predict future diabetes risk and, if so, would have thresholds that identify the same degree of risk as the diagnosis of prediabetes on postpartum measurement of A1c.

METHODS

With population-based administrative databases, we identified all women in Ontario, Canada, who had a GCT in pregnancy with delivery between January 2007 and December 2017, followed by measurement of A1c and fasting glucose within 2 years postpartum (n = 141 858, including 19 034 with GDM). Women were followed over a median of 3.5 years for the development of diabetes.

RESULTS

Under the assumption of a linear exposure effect, the 1-hour post-challenge glucose concentration on the GCT was associated with an increased likelihood of developing diabetes (hazard ratio 1.39; 95% CI, 1.38-1.40). A GCT threshold of 8.0 mmol/L predicted the same 5-year risk of diabetes (6.0%; 95% CI, 5.8-6.2) as postpartum A1c 5.7% (identifying prediabetes). Moreover, in women with GDM, a GCT threshold of 9.8 mmol/L equaled prediabetes on postpartum A1c in predicting a 5-year risk of diabetes of 16.5% (14.8-18.2).

CONCLUSION

The GCT offers predictive capacity for future diabetes in pregnant women. In women with GDM, this insight could identify those at highest risk of diabetes, toward whom postpartum screening efforts should be most strongly directed.

Glucose intolerance in pregnancy and risk of early-onset type 2 diabetes: a population-based cohort study

BACKGROUND

The risk of type 2 diabetes among women with glucose intolerance during pregnancy that does not meet gestational diabetes criteria requires further investigation. We aimed to explore the associations between various degrees of gestational glucose intolerance and the risk of type 2 diabetes in young adulthood.

METHODS

For this population-based cohort study, the national Israeli conscription database was linked to Maccabi Healthcare Services (MHS), the second-largest state-mandated health provider in Israel. We included 177 241 women who underwent a pre-recruitment evaluation at adolescence (age 16-20 years), 1 year before mandatory military service, and later underwent, from Jan 1, 2001, to Dec 31, 2019, two-step gestational diabetes screening with a 50 g glucose challenge test (GCT) based on a threshold of 140 mg/dL (7·8 mmol/L), followed as needed by a 100 g oral glucose tolerance test (OGTT). Abnormal OGTT values were defined according to the Carpenter-Coustan thresholds: 95 mg/dL (5·3 mmol/L) or higher in the fasting state; 180 mg/dL (10·0 mmol/L) or higher at 1 h; 155 mg/dL (8·6 mmol/L) or higher at 2 h; and 140 mg/dL (7·8 mmol/L) or higher at 3 h. The primary outcome was incident type 2 diabetes in the MHS diabetes registry. Cox proportional hazards models were applied to estimate adjusted hazard ratios (HRs) with 95% CIs for incident type 2 diabetes.

FINDINGS

During a cumulative follow-up of 1 882 647 person-years, and with a median follow-up of 10·8 (IQR 5·2-16·4) years, 1262 women were diagnosed with type 2 diabetes. Crude incidence rates of type 2 diabetes were 2·6 (95% CI 2·4-2·9) per 10 000 person-years in women with gestational normoglycaemia, 8·9 (7·4-10·6) per 10 000 person-years in women with an abnormal GCT and normal OGTT, 26·1 (22·4-30·1) per 10 000 person-years in women with one abnormal OGTT value (in the fasting state or 1 h, 2 h, or 3 h post-challenge), and 71·9 (66·0-78·3) per 10 000 person-years in women with gestational diabetes. After adjustment for sociodemographic characteristics, adolescent BMI, and age at gestational screening, the risk of type 2 diabetes was higher, compared to the gestational normoglycaemia group, in women with an abnormal GCT and normal OGTT (adjusted hazard ratio [HR] 3·39 [95% CI 2·77-4·16]; p<0·0001), in women with one abnormal OGTT value (9·11 [7·64-10·86]; p<0·0001), and in women with gestational diabetes (24·84 [21·78-28·34]; p<0·0001). The risk of type 2 diabetes was modestly increased in women with isolated elevated fasting glucose (adjusted HR 11·81 [95% CI 8·58-16·25]; p<0·0001), and in women with gestational diabetes and an abnormal fasting glucose (38·02 [32·41-44·61]; p<0·0001).

INTERPRETATION

Gestational glucose intolerance, including conditions not meeting gestational diabetes criteria of the two-step strategy, confers a high risk of type 2 diabetes in young adulthood. These conditions should be recognised as risk factors for type 2 diabetes, especially among women with abnormal fasting glucose concentrations during pregnancy.

FUNDING

None.

Association between gestational abnormal glucose tolerance and maternal-fetal outcomes

AIM

To investigate the relationship between abnormal glucose tolerance during pregnancy and maternal-fetal outcomes, after categorizing women into groups with different levels of gestational abnormal glucose tolerance.

METHODS

A total of 1858 pregnant women who received two-step screening for gestational diabetes mellitus (GDM) at Fooyin University Hospital were categorized into four groups, according to their glucose abnormalities, and their maternal-fetal outcomes were investigated from October 2015 to June 2020.

RESULTS

Among the groups having different levels of abnormal glucose tolerance, there were significant differences and trends in mother's age, currently married status, and prepregnancy overweight or obesity, incidences of cesarean section, preterm, and gestational hypertension or preeclampsia; and with respect to neonatal incidence of large for gestational age (LGA), average weight, and average height (p < 0.05). After adjusting for potential factors, there were higher incidences of cesarean section (AOR = 1.71; 95% confidence interval [CI]: 1.12-2.61), preterm (AOR = 2.20; 95% CI: 1.23-3.91), neonatal LGA (AOR = 4.94; 95% CI: 2.87-8.51), and neonatal intensive care unit (NICU) admission (AOR = 2.66; 95% CI: 1.14-6.24) in the GDM group, relative to the control group. Furthermore, the women in the oral glucose tolerance test (OGTT)-1 group had a higher incidence of neonatal LGA when compared with the women in the normal group (AOR = 2.31; 95% CI: 1.02-5.33).

CONCLUSIONS

We found higher incidences of cesarean section, preterm, and neonatal LGA and NICU admission in the GDM women, and a higher incidence of neonatal LGA in the OGTT-1 group, relative to control group.

Urinary phthalate and DINCH metabolite concentrations and gradations of maternal glucose intolerance

BACKGROUND

Studies suggest a link between pregnancy phthalate exposures and gestational diabetes mellitus (GDM). Few studies have evaluated associations between phthalate biomarkers (individual or mixtures) with gradations of maternal glucose intolerance.

METHODS

In a subset of 606 women participating in LIFECODES pregnancy cohort, a combination of 50-gram 1-h non-fasting glucose load test (GLT) and 100-gram 3-h fasting oral glucose tolerance test was used to determine pregnancy glycemic status (median: 27 weeks gestation): normoglycemia (n = 136), impaired glucose tolerance (IGT) (n = 296), and GDM (n = 174). Nineteen metabolites of phthalates and their replacements were measured during each trimester. We used multivariable logistic regression models to evaluate associations between biomarkers (in quartiles) and maternal glycemic status (GDM v. normoglycemia and IGT v. normoglycemia), adjusting for potential confounders. We also used principal component analysis to evaluate associations jointly accounting for metabolites as chemical mixtures.

RESULTS

Higher 1st trimester mono-3-carboxypropyl phthalate (MCPP) was associated with decreased odds of GDM (Q4 v. Q1: 0.30; 95% CI: 0.13, 0.67) and IGT (Q4 v. Q1 OR: 0.37; 95% CI: 0.17, 0.79). Higher 2nd trimester mono-isobutyl phthalate (MiBP) was associated with increased IGT (Q4 v. Q1 OR: 2.07; 95% CI: 1.06, 4.07), and 2nd trimester mono-3-hydroxybutyl phthalate (MHBP) was non-monotonically associated with increased GDM (Q2 v. Q1 OR: 3.21; 95% CI: 1.54, 6.87). Mixture analyses showed similar associations (Q4 v. Q1 for 2nd trimester dibutyl phthalates metabotlites mixtures OR: 2.08; 95% CI: 1.04, 4.22).

CONCLUSION

Some phthalate biomarkershad trimester-specific associations with glycemic outcomes, with long and short term health implications.

The association of parity/live birth number with incident type 2 diabetes among women: over 15 years of follow-up in The Tehran Lipid and Glucose Study

Background

Childbearing may increase the future risk of developing type 2 diabetes mellitus (T2DM) in mothers. However, the issue is not clear completely and not investigated in the Middle East, a region with a high burden of T2DM. In the current study, we examined the association of parity/live birth number with incident T2DM among Iranian women.

Methods

The study population included 2552 women aged 30–65 years recruited in 1999–2001 and were followed for incident T2DM by 3-year intervals. Multivariable Cox proportional hazard models were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of the parity/live birth number for incident T2DM. Parity number was defined as the number of live childbirth (number of live birth) plus the number of stillbirth (defined as birth of an infant that died after the 20th week of pregnancy in the uterus).

Results

During a median follow-up of 15.4 years, 557 incident T2DM cases have occurred. After adjustment for potential T2DM risk factors and reproductive factors, each additional parity caused a 9% higher risk for incident T2DM. Moreover, compared to women with one parity, those with 3 and ≥ 4 parity had HRs of 1.73 [95% CI: 1.06–2.83] and 2.23 [1.36–3.65], respectively. After further adjustment for body mass index (BMI) and waist circumference, although the HRs were attenuated prominently, parity ≥ 4 was associated with significantly higher risk (HR: 1.72 [1.05–2.83]); even after further adjustment for triglycerides (TG)/ high-density lipoprotein cholesterol (HDL-C), the risk remained marginally significant (HR: 1.64 [1.00–2.70; P value: 0.051]). For the number of live birth, the results were also similar. Moreover, in a sensitivity analysis, when we considered BMI change during follow-up as another covariate, generally, the effect sizes did not change; the trend of HRs across categories of parity number remained marginally significant (P value: 0.064).

Conclusions

During a long-term follow-up, after adjustment for potential T2DM risk factors, reproductive factors, obesity indices, and TG/HDL-C (insulin resistance surrogate), we demonstrated that higher parity/live birth numbers could be associated with increased risk of T2DM development among Iranian women. Moreover, even after further adjustment for BMI change, the suggestive higher risk was still found.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-021-01519-7.

Ambient PM gross β-activity and glucose levels during pregnancy

BACKGROUND

Exposure to ionizing radiation has been associated with insulin resistance and type 2 diabetes. In light of recent work showing an association between ambient particulate matter (PM) gross β-activity and gestational diabetes mellitus (GDM) among pregnant women, we examined pregnancy glucose levels in relation to PM gross β-activity to better understand this pathway.

METHODS

Our study included 103 participants receiving prenatal care at Beth Israel Deaconess Medical Center in Boston, MA. PM gross β-activity was obtained from US Environmental Protection Agency's RadNet program monitors, and blood glucose levels were obtained from the non-fasting glucose challenge test performed clinically as the first step of the 2-step GDM screening test. For each exposure window we examined (i.e., moving average same-day, one-week, first-trimester, and second-trimester PM gross β-activity), we fitted generalized additive models and adjusted for clinical characteristics, socio-demographic factors, temporal variables, and PM with an aerodynamic diameter ≤ 2.5 μm (PM_2.5). Subgroup analyses by maternal age and by body mass index were also conducted.

RESULTS

An interquartile range increase in average PM gross β-activity during the second trimester of pregnancy was associated with an increase of 17.5 (95% CI: 0.8, 34.3) mg/dL in glucose concentration. Associations were stronger among younger and overweight/obese participants. Our findings also suggest that the highest compared to the lowest quartile of one-week exposure was associated with 17.0 (95% CI: - 4.0, 38.0) mg/dL higher glucose levels. No associations of glucose were observed with PM gross β-activity during same-day and first-trimester exposure windows. PM_2.5 was not associated with glucose levels during any exposure window in our data.

CONCLUSIONS

Exposure to higher levels of ambient PM gross β-activity was associated with higher blood glucose levels in pregnant patients, with implications for how this novel environmental factor could impact pregnancy health.

Review of methods for detecting glycemic disorders

Prediabetes (intermediate hyperglycemia) consists of two abnormalities, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) detected by a standardized 75-gram oral glucose tolerance test (OGTT). Individuals with isolated IGT or combined IFG and IGT have increased risk for developing type 2 diabetes (T2D) and cardiovascular disease (CVD). Diagnosing prediabetes early and accurately is critical in order to refer high-risk individuals for intensive lifestyle modification. However, there is currently no international consensus for diagnosing prediabetes with HbA1c or glucose measurements based upon American Diabetes Association (ADA) and the World Health Organization (WHO) criteria that identify different populations at risk for progressing to diabetes. Various caveats affecting the accuracy of interpreting the HbA1c including genetics complicate this further. This review describes established methods for detecting glucose disorders based upon glucose and HbA1c parameters as well as novel approaches including the 1-hour plasma glucose (1-h PG), glucose challenge test (GCT), shape of the glucose curve, genetics, continuous glucose monitoring (CGM), measures of insulin secretion and sensitivity, metabolomics, and ancillary tools such as fructosamine, glycated albumin (GA), 1,5- anhydroglucitol (1,5-AG). Of the approaches considered, the 1-h PG has considerable potential as a biomarker for detecting glucose disorders if confirmed by additional data including health economic analysis. Whether the 1-h OGTT is superior to genetics and omics in providing greater precision for individualized treatment requires further investigation. These methods will need to demonstrate substantially superiority to simpler tools for detecting glucose disorders to justify their cost and complexity.

Association of Gestational Diabetes With Maternal Disorders of Glucose Metabolism and Childhood Adiposity

IMPORTANCE

The sequelae of gestational diabetes (GD) by contemporary criteria that diagnose approximately twice as many women as previously used criteria are unclear.

OBJECTIVE

To examine associations of GD with maternal glucose metabolism and childhood adiposity 10 to 14 years' postpartum.

DESIGN, SETTING, AND PARTICIPANTS

The Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study established associations of glucose levels during pregnancy with perinatal outcomes and the follow-up study evaluated the long-term outcomes (4697 mothers and 4832 children; study visits occurred between February 13, 2013, and December 13, 2016).

EXPOSURES

Gestational diabetes was defined post hoc using criteria from the International Association of Diabetes and Pregnancy Study Groups consisting of 1 or more of the following 75-g oral glucose tolerance test results (fasting plasma glucose ≥92 mg/dL; 1-hour plasma glucose level ≥180 mg/dL; 2-hour plasma glucose level ≥153 mg/dL).

MAIN OUTCOMES AND MEASURES

Primary maternal outcome: a disorder of glucose metabolism (composite of type 2 diabetes or prediabetes). Primary outcome for children: being overweight or obese; secondary outcomes: obesity, body fat percentage, waist circumference, and sum of skinfolds (>85th percentile for latter 3 outcomes).

RESULTS

The analytic cohort included 4697 mothers (mean [SD] age, 41.7 [5.7] years) and 4832 children (mean [SD] age, 11.4 [1.2] years; 51.0% male). The median duration of follow-up was 11.4 years. The criteria for GD were met by 14.3% (672/4697) of mothers overall and by 14.1% (683/4832) of mothers of participating children. Among mothers with GD, 52.2% (346/663) developed a disorder of glucose metabolism vs 20.1% (791/3946) of mothers without GD (odds ratio [OR], 3.44 [95% CI, 2.85 to 4.14]; risk difference [RD], 25.7% [95% CI, 21.7% to 29.7%]). Among children of mothers with GD, 39.5% (269/681) were overweight or obese and 19.1% (130/681) were obese vs 28.6% (1172/4094) and 9.9% (405/4094), respectively, for children of mothers without GD. Adjusted for maternal body mass index during pregnancy, the OR was 1.21 (95% CI, 1.00 to 1.46) for children who were overweight or obese and the RD was 3.7% (95% CI, -0.16% to 7.5%); the OR was 1.58 (95% CI, 1.24 to 2.01) for children who were obese and the RD was 5.0% (95% CI, 2.0% to 8.0%); the OR was 1.35 (95% CI, 1.08 to 1.68) for body fat percentage and the RD was 4.2% (95% CI, 0.9% to 7.4%); the OR was 1.34 (95% CI, 1.08 to 1.67) for waist circumference and the RD was 4.1% (95% CI, 0.8% to 7.3%); and the OR was 1.57 (95% CI, 1.27 to 1.95) for sum of skinfolds and the RD was 6.5% (95% CI, 3.1% to 9.9%).

CONCLUSIONS AND RELEVANCE

Among women with GD identified by contemporary criteria compared with those without it, GD was significantly associated with a higher maternal risk for a disorder of glucose metabolism during long-term follow-up after pregnancy. Among children of mothers with GD vs those without it, the difference in childhood overweight or obesity defined by body mass index cutoffs was not statistically significant; however, additional measures of childhood adiposity may be relevant in interpreting the study findings.

Postpartum glucose intolerance: an updated overview

The prevalence of type 2 diabetes mellitus has increased worldwide over the past three decades, as a consequence of the more westernized lifestyle, which is responsible for the increasing obesity rate in the modern adult's life. Concomitant with this increase there has been a gradual rise in the overall prevalence of gestational diabetes mellitus, a condition that strongly predisposes to overt diabetes later in life. Many women with previous gestational diabetes mellitus show glucose intolerance in the early postpartum period. Although the best screening strategy for postpartum glucose intolerance is still debated, numerous evidences indicate that identification of these women at this time is of critical importance, as efforts to initiate early intensive lifestyle modification, including hypocaloric diet and physical activity, and to ameliorate the metabolic profile of these high-risk subjects can prevent or delay the onset of type 2 diabetes mellitus. Nevertheless, less than one fifth of women attend the scheduled postpartum screening following gestational diabetes mellitus and they are at increased risk to develop type 2 diabetes mellitus later in their lives. Unsatisfying results have also come from early intervention strategies and tools that have been developed during the last few years to help improving the rate of adherence to postpartum glycemic testing, thereby indicating that more effective strategies are needed to improve women's participation in postpartum screening.

Single abnormal value on 3-hour oral glucose tolerance test during pregnancy is associated with adverse maternal and neonatal outcomes: a systematic review and metaanalysis

OBJECTIVE DATA

The purpose of this study was to determine whether women with 1 abnormal value on 3-hour 100-g oral glucose tolerance test are at an increased risk for adverse pregnancy outcomes.

STUDY

Gestational diabetes mellitus is diagnosed by a 2-step method, with a 3-hour, 100-g oral glucose tolerance test that is reserved for women with an abnormal 1-hour, 50-g glucose challenge test. Although the increased maternal-fetal morbidity with gestational diabetes mellitus is well established, controversy remains about the risk that is associated with an isolated abnormal value during a 3-hour, 100-g oral glucose tolerance test.

STUDY APPRAISAL AND SYNTHESIS METHODS

Prospective and retrospective studies that evaluated the maternal and perinatal impact of 1 abnormal glucose value during a 3-hour, 100-g oral glucose tolerance test were identified with the use of computerized databases. Data were extracted and quantitative analyses were performed.

RESULTS

Twenty-five studies (7 prospective and 18 retrospective) that met criteria for metaanalysis included 4466 women with 1 abnormal glucose value on oral glucose tolerance test. Patients with 1 abnormal glucose value had significantly worse pregnancy outcomes compared with women with zero abnormal values with the following pooled odds ratios: macrosomia, 1.59 (95% confidence interval, 1.16-2.19); large for gestational age, 1.38 (95% confidence interval, 1.09-1.76); increased mean birthweight, 44.5 g (95% confidence interval, 8.10-80.80 g); neonatal hypoglycemia, 1.88 (95% confidence interval, 1.05-3.38); total cesarean delivery, 1.69 (95% confidence interval, 1.40-2.05); pregnancy-induced hypertension, 1.55 (95% confidence interval, 1.31-1.83), and Apgar score of <7 at 5 minutes, 6.10 (95% confidence interval, 2.65-14.02). There was also an increase in neonatal intensive care unit admission and respiratory distress syndrome. Similar results were seen that compared 1 abnormal glucose value to a population with a normal 1-hour 50-g glucose challenge test (normal glucose screen). With the exception of birthweight, outcomes of patients with 1 abnormal glucose value were similar to outcomes of patients with gestational diabetes mellitus.

CONCLUSION

Women with 1 abnormal value on 3-hour, 100-g oral glucose tolerance test have a significantly increased risk for poor outcomes comparable with women who have gestational diabetes mellitus.

Pregnancy Hyperglycaemia and Risk of Prenatal and Postpartum Depressive Symptoms

BACKGROUND

Glucose dysregulation in pregnancy may affect maternal depressive symptoms during the prenatal and postpartum periods via both physiologic and psychological pathways.

METHODS

During mid-pregnancy, a combination of 50-g 1-h non-fasting glucose challenge test (GCT) and 100-g 3-h fasting oral glucose tolerance test was used to determine pregnancy glycaemic status among women participating in Project Viva: normal glucose tolerance (NGT), isolated hyperglycaemia (IHG), impaired glucose tolerance (IGT) and gestational diabetes mellitus (GDM). Using the Edinburgh Postnatal Depression Scale (EPDS), we assessed depressive symptoms at mid-pregnancy and again at 6 months postpartum. We used logistic regression, adjusted for sociodemographic, anthropometric and lifestyle factors, to estimate the odds of elevated prenatal and postpartum depressive symptoms (EPDS ≥ 13 on 0-30 scale) in relation to GCT glucose levels and GDM status in separate models.

RESULTS

A total of 9.6% of women showed prenatal and 8.4% postpartum depressive symptoms. Women with higher GCT glucose levels were at greater odds of elevated prenatal depressive symptoms [multivariable-adjusted odds ratio (OR) per standard deviation (SD) increase in glucose levels (27 mg/dL): 1.25; 95%: 1.07, 1.48]. Compared with NGT women, the association appeared stronger among women with IHG [OR: 1.80; 95% confidence interval (CI): 1.08, 3.00] than among those with GDM (OR: 1.45; 95% CI: 0.72, 2.91) or IGT (OR: 1.43; 95% CI: 0.59, 3.46). Neither glucose levels assessed from the GCT nor pregnancy glycaemic status were significantly associated with elevated postpartum depressive symptoms.

CONCLUSION

Pregnancy hyperglycaemia was cross-sectionally associated with higher risk of prenatal depressive symptoms, but not with postpartum depressive symptoms.

Incorporating first trimester analytes to predict delivery of a large for gestational infant in women with impaired glucose tolerance

AIM

To investigate first trimester maternal characteristics of women with impaired glucose tolerance that deliver large for gestational age (LGA) infants.

METHODS

Nested analysis from a prospective study of singleton pregnancies enrolled at first trimester. We studied women with an abnormal 1 h glucose challenge test that had normal follow-up oral glucose tolerance testing. Maternal characteristics, ultrasound parameters and serum analytes were stratified by subsequent delivery of an LGA infant. Parameters identified as significant on univariate analysis were used for a derivation of prediction by logistic regression. Odds ratio and prediction performance was determined using receiver operator curve (ROC) statistics.

RESULTS

A total of 33/114 (28.9%) women meeting the criteria delivered LGA infants. Maternal height (cm), and first trimester pregnancy-associated protein-A and free β-hCG (MoM) predicted delivery of an LGA infant (ROC area under curve 0.73; 95% CI 0.63-0.83). At a cutoff value of 0.172 the prediction rule achieved 91% sensitivity, 44% specificity, 41% positive predictive and 92% negative predictive value.

CONCLUSION

Maternal height and first trimester high free β-hCG and PAPP-A levels may be used as predictors for delivery of LGA infants in women with impaired glucose tolerance.

Abnormal glucose tolerance later in life in women affected by glucose intolerance during pregnancy

Gestational diabetes mellitus (GDM) is a condition of abnormal maternal glucose tolerance that occurs, or is detected, for the first time during pregnancy. The new diagnostic strategies recommend a 75 g, 2-h glucose tolerance test for all women not already known to be diabetic, in the early 3rd trimester of pregnancy. GDM is diagnosed when one or more values is equal to or exceeds the thresholds suggested (i.e. fasting ≥ 5.1 mmol/l, 1-h ≥ 10.0 mmol/l and 2-h ≥ 8.5 mmol/l). This criteria will determine a significant increase of the prevalence of GDM, primarily because only one abnormal value (OAV), not two, is sufficient to make the diagnosis. We also suppose that the new cases of gestational diabetes diagnosed with the new criteria will have an increased risk for subsequent abnormal glucose tolerance later in life, as it was largely confirmed in the past for the patients with two or more abnormal values.

Type 2 diabetes after gestational diabetes: The influence of changing diagnostic criteria

A previous diagnosis of gestational diabetes (GDM) carries a lifetime risk of progression to type 2 diabetes of up to 60%. Identification of those women at higher risk of progression to diabetes allows the timely introduction of measures to delay or prevent diabetes onset. However, there is a large degree of variability in the literature with regard to the proportion of women with a history of GDM who go on to develop diabetes. Heterogeneity between cohorts with regard to diagnostic criteria used, duration of follow-up, and the characteristics of the study population limit the ability to make meaningful comparisons across studies. As the new International Association for Diabetes in Pregnancy Study Group criteria are increasingly adopted worldwide, the prevalence of GDM is set to increase by two-to three-fold. Here, we review the literature to examine the evolution of diagnostic criteria for GDM, the implications of changing criteria on the proportion of women with previous GDM progressing to diabetes, and how the use of different diagnostic criteria may influence the development of appropriate follow-up strategies.

Each degree of glucose intolerance in pregnancy predicts distinct trajectories of β-cell function, insulin sensitivity, and glycemia in the first 3 years postpartum

OBJECTIVE

Glucose intolerance in pregnancy predicts an increased risk of future type 2 diabetes mellitus (T2DM) that is proportional to the severity of antepartum dysglycemia (i.e., highest in women with gestational diabetes mellitus [GDM], followed by those with milder dysglycemia). However, the pathophysiologic changes driving this risk are not known. Thus, we evaluated the longitudinal changes in β-cell function, insulin sensitivity, and glycemia in the first 3 years postpartum after gestational dysglycemia.

RESEARCH DESIGN AND METHODS

A total of 337 women underwent glucose challenge test (GCT) and oral glucose tolerance test (OGTT) in pregnancy, followed by repeat OGTT at 3 months, 1 year, and 3 years postpartum. The antepartum GCT/OGTT identified four gestational glucose tolerance groups: GDM (n = 105); gestational impaired glucose tolerance (GIGT; n = 60); abnormal GCT, followed by normal glucose tolerance (NGT) on the OGTT (abnormal GCT NGT; n = 96); and normal GCT with NGT (n = 76).

RESULTS

At each of 3 months, 1 year, and 3 years postpartum, the prevalence of glucose intolerance increased from normal GCT NGT to abnormal GCT NGT to GIGT to GDM (all P < 0.001), whereas β-cell function, assessed by the Insulin Secretion-Sensitivity Index-2 (ISSI-2), and insulin sensitivity (Matsuda index), progressively decreased across the groups (all P < 0.002). Each group predicted distinct trajectories of ISSI-2, Matsuda index, and fasting and 2-h glucose (all P < 0.001). Notably, GDM, GIGT, and abnormal GCT NGT predicted varying rates of declining β-cell function and insulin sensitivity, as well as rising glycemia, compared with normal GCT NGT.

CONCLUSIONS

Each degree of gestational glucose intolerance predicts distinct trajectories of β-cell function, insulin sensitivity, and glycemia in the first 3 years postpartum that drive their differential risk of future T2DM.

Predictors of postpartum glucose tolerance testing in italian women with gestational diabetes mellitus

Postpartum screening is critical for early identification of type 2 diabetes in women previously diagnosed with gestational diabetes mellitus (GDM). Nevertheless, its rate remains disappointingly low. Thus, we plan to examine the rate of postpartum glucose tolerance test (ppOGTT) for Italian women with GDM, before and after counseling, and identify demographic, clinical, and/or biochemical predictors of adherence. With these aims, we retrospectively enrolled 1159 women with GDM, in Calabria, Southern Italy, between 2004 and 2011. During the last year, verbal and written counseling on the importance of followup was introduced. Data were analyzed by multiple regression analysis. A significant increase of the return rate was observed following introduction of the counseling [adjusted odds ratio (AOR) 5.17 (95% CI, 3.83–6.97), P < 0.001]. Interestingly, previous diagnosis of polycystic ovary syndrome (PCOS) emerged as the major predictor of postpartum followup [AOR 5.27 (95% CI, 3.51–8.70), P < 0.001], even after stratification for the absence of counseling. Previous diagnosis of GDM, higher educational status, and insulin treatment were also relevant predictors. Overall, our data indicate that counseling intervention is effective, even if many women fail to return, whereas PCOS represents a new strong predictor of adherence to postpartum testing.

The lipid accumulation product for the early prediction of gestational insulin resistance and glucose dysregulation

BACKGROUND

Recent insights linking insulin resistance and lipid overaccumulation suggest a novel approach for the early identification of women who may soon experience glucose dysregulation. Among women without a history of gestational diabetes, we tested the association between the lipid accumulation product (LAP) obtained in early pregnancy and glucose dysregulation or insulin resistance in the second trimester.

METHODS

A total of 180 white pregnant women of French-Canadian origin were included in this study. At 11–14 weeks' gestation, fasting insulin, glucose, C-peptide concentrations, and estimated insulin resistance (HOMA-IR) were obtained. The waist circumference (WC) and fasting triglycerides (TG) were measured to calculate LAP as(WC[cm] - 58) · TG[mmol/L]. At 24–28 weeks' gestation, glucose was measured 2 hours after a 75-g oral glucose challenge and other fasting variables were repeated.

RESULTS

Among the nulliparous women tested at the end of the second trimester, fasting insulin, C-peptide, insulin resistance (HOMA-IR index), fasting glucose, and 2-hour glucose progressively increased ( p £ 0.002)according to their first-trimester LAP tertiles. Similar results were observed in parous women except for the glucose variables. The first-trimester LAP tended to show a stronger correlation to the second-trimester HOMAIR index (r = 0.56) than fasting triglyceride levels alone (r = 0.40) or waist circumference alone (r = 0.44) among nulliparous women. Similar associations were observed for parous women. Adjustment for body mass index weakened these associations, especially among parous women.

CONCLUSIONS

An increased value of LAP at the beginning of a pregnancy could be associated with an increased risk of insulin resistance or hyperglycemia later in gestation.

Maternal and preterm fetal sheep responses to dexmedetomidine

BACKGROUND

The α(2) adrenergic receptor agonist dexmedetomidine has some unique pharmacologic properties that could benefit pregnant patients (and their fetuses) when they require sedation, analgesia, and/or anesthesia during pregnancy. The purpose of the present study was to delineate maternal and fetal responses to an intravenous infusion of dexmedetomidine.

METHODS

This study was conducted on surgically-recovered preterm sheep instrumented for physiologic recording and blood sampling. Maternal and fetal cardiovascular and blood gas parameters and fetal cerebral oxygenation levels were recorded before, during, and after 3h of dexmedetomidine infusion to the ewe at a rate of 1 μg/kg/h.

RESULTS

Drug infusion produced overt sedation but no apparent respiratory depression as evidenced by stable maternal arterial blood gases; fetal blood gases were also stable. The one blood parameter to change was serum glucose, By the end of the 3-h infusion, glucose increased from 49±10 to 104±33mg/dL in the ewe and from 22±3 to 48±16mg/dL in the fetus; it declined post-drug exposure but remained elevated compared to the starting levels (maternal, 63±12mg/dL, P=0.0497; and fetal, 24±4mg/dL, P=0.012). With respect to cardiovascular status, dexmedetomidine produced a decrease in maternal blood pressure and heart rate with fluctuations in uterine blood flow but had no discernable effect on fetal heart rate or mean arterial pressure. Likewise, maternal drug infusion had no effect on fetal cerebral oxygenation, as measured by in utero near-infrared spectroscopy.

CONCLUSIONS

Using a clinically-relevant dosing regimen, intravenous infusion of dexmedetomidine produced significant maternal sedation without altering fetal physiologic status. Results from this initial acute assessment support the conduct of further studies to determine if dexmedetomidine has clinical utility for sedation and pain control during pregnancy.

Maternal adaptations and inheritance in the transgenerational programming of adult disease

Adverse exposures in utero have long been linked with an increased susceptibility to adult cardio-renal and metabolic diseases. Clear gender differences exist, whereby growth-restricted females, although exhibiting some phenotypic modifications, are often protected from overt disease outcomes. One of the greatest physiological challenges facing the female gender, however, is that of pregnancy; yet little research has focused on the outcomes associated with this, as a potential 'second-hit' for those who were small at birth. We review the limited evidence suggesting that pregnancy may unmask cardio-renal and metabolic disease states and the consequences for long-term maternal health in females who were born small. Additionally, a growing area of research in this programming field is in the transgenerational transmission of low birth weight and disease susceptibility. Pathways for transmission might include an abnormal adaptation to pregnancy by the growth-restricted mother and/or inheritance via the parental germline. Strategies to optimise the pregnancy environment and/or prevent the consequences of inheritance of programmed deficits and dysfunction are of critical importance for future generations.

1-Hour OGTT Plasma Glucose as a Marker of Progressive Deterioration of Insulin Secretion and Action in Pregnant Women

Considering old GDM diagnostic criteria, alterations in insulin secretion and action are present in women with GDM as well as in women with one abnormal value (OAV) during OGTT. Our aim is to assess if changes in insulin action and secretion during pregnancy are related to 1-hour plasma glucose concentration during OGTT. We evaluated 3 h/100 g OGTT in 4,053 pregnant women, dividing our population on the basis of 20 mg/dL increment of plasma glucose concentration at 1 h OGTT generating 5 groups (<120 mg/dL, n = 661; 120-139 mg/dL, n = 710; 140-159 mg/dL, n = 912; 160-179 mg/dL, n = 885; and ≥180 mg/dL, n = 996). We calculated incremental area under glucose (AUC(gluc)) and insulin curves (AUC(ins)), indexes of insulin secretion (HOMA-B), and insulin sensitivity (HOMA-R), AUC(ins)/AUC(gluc). AUC(gluc) and AUC(ins) progressively increased according to 1-hour plasma glucose concentrations (both P < 0.0001 for trend). HOMA-B progressively declined (P < 0.001), and HOMA-R progressively increased across the five groups. AUC(ins)/AUC(gluc) decreased in a linear manner across the 5 groups (P < 0.001). Analysing the groups with 1-hour value <180 mg/dL, defects in insulin secretion (HOMA-B: -29.7%) and sensitivity (HOMA-R: +15%) indexes were still apparent (all P < 0.001). Progressive increase in 1-hour OGTT is associated with deterioration of glucose tolerance and alterations in indexes of insulin action and secretion.

Gestational glucose tolerance and maternal metabolic profile at 3 years postpartum

OBJECTIVE

To estimate the independent effect of gestational impaired glucose tolerance, defined as a single abnormal oral glucose tolerance test value, on metabolic dysfunction at 3 years postpartum.

METHODS

We used multiple linear regression to measure associations between glucose testing during pregnancy and metabolic markers at 3 years postpartum in Project Viva, a prospective cohort study of maternal and infant health. We compared metabolic measures at 3 years postpartum among four groups: normal glucose challenge test (less than 140 mg/dL, n=461); abnormal glucose challenge test but normal glucose tolerance test (n=39); impaired glucose tolerance (a single abnormal glucose tolerance test value, n=21); and gestational diabetes mellitus (n=16).

RESULTS

Adjusting for age, race, parity, parental history of diabetes, and maternal body mass index at 3 years postpartum, we found women with gestational diabetes mellitus had lower adiponectin (11.2 ng/mL compared with 20.7 ng/mL) and higher homeostatic model assessments of insulin resistance (3.1 compared with 1.3) and waist circumference (91.3 cm compared with 86.2 cm) compared with women with impaired glucose tolerance or normal glucose tolerance. Women in both the impaired glucose tolerance and gestational diabetes mellitus groups had lower high-density lipoprotein (gestational diabetes mellitus 44.7 mg/dL; impaired glucose tolerance 45.4/dL compared with normal glucose tolerance 55.8 mg/dL) and higher triglycerides (gestational diabetes mellitus 136.1 mg/dL; impaired glucose tolerance 140.1 mg/dL compared with normal glucose tolerance 78.3) compared with women in the normal glucose tolerance group. We found the highest values for hemoglobin A1c (gestational diabetes mellitus 5.1%, impaired glucose tolerance 5.3%, normal glucose tolerance 5.1%) and high-sensitivity C-reactive protein (gestational diabetes mellitus 1.4 mg/dL, impaired glucose tolerance 2.2 mg/dL, normal glucose tolerance 1.0 mg/dL) among women with impaired glucose tolerance.

CONCLUSION

Gestational diabetes mellitus and impaired glucose tolerance during pregnancy are associated with persistent metabolic dysfunction at 3 years postpartum, independent of other clinical risk factors.

Cardio-renal and metabolic adaptations during pregnancy in female rats born small: implications for maternal health and second generation fetal growth

Intrauterine growth restriction caused by uteroplacental insufficiency increases risk of cardiovascular and metabolic disease in offspring. Cardio-renal and metabolic responses to pregnancy are critical determinants of immediate and long-term maternal health. However, no studies to date have investigated the renal and metabolic adaptations in growth restricted offspring when they in turn become pregnant. We hypothesised that the physiological challenge of pregnancy in growth restricted females exacerbates disease outcome and compromises next generation fetal growth. Uteroplacental insufficiency was induced by bilateral uterine vessel ligation (Restricted) or sham surgery (Control) on day 18 of gestation in WKY rats and F1 female offspring birth and postnatal body weights were recorded. F1 Control and Restricted females were mated at 4 months and blood pressure, renal and metabolic parameters were measured in late pregnancy and F2 fetal and placental weights recorded. Age-matched non-pregnant Control and Restricted F1 females were also studied. F1 Restricted females were born 10-15% lighter than Controls. Basal insulin secretion and pancreatic β-cell mass were reduced in non-pregnant Restricted females but restored in pregnancy. Pregnant Restricted females, however, showed impaired glucose tolerance and compensatory glomerular hypertrophy, with a nephron deficit but normal renal function and blood pressure. F2 fetuses from Restricted mothers exposed to physiological measures during pregnancy were lighter than Controls highlighting additive adverse effects when mothers born small experience stress during pregnancy. Female rats born small exhibit mostly normal cardio-renal adaptations but altered glucose control during late pregnancy making them vulnerable to lifestyle challenges.

Contribution of first trimester fasting plasma insulin levels to the incidence of glucose intolerance in later pregnancy: Tanaka women's clinic study

AIMS

To clarify risk factors predictive of glucose intolerance in later pregnancy.

METHODS

We prospectively studied 509 pregnant women who visited the obstetrics clinic in Tokyo prior to week 13 of gestation, between September 2008 and January 2010. Biochemical parameters were measured in fasting plasma samples collected at week 8.0 ± 2.0 of gestation. A 50 g glucose challenge test (GCT) was performed between weeks 26 and 29: plasma glucose levels ≥ 7.8 mmol/l 1h after ingestion indicated a positive GCT. Logistic regression was performed, adjusting for relevant covariates.

RESULTS

We identified 114 patients with positive GCTs, including 8 with gestational diabetes mellitus (GDM). After correcting for baseline body mass index, only the homeostasis model assessment of insulin resistance value remained a significant predictor of GCT positivity (OR 2.07; 1.21-3.55). We identified threshold values of fasting plasma glucose (FPG) ≥ 3.66 mmol/l and fasting plasma insulin (FPI) ≥ 36.69 pmol/l as indicative of a higher risk of positive GCT (OR 2.38; 1.49-3.80).

CONCLUSIONS

First trimester FPI levels improve the predictive ability of FPG level on subsequent GCT positivity.

Outcomes in women with a history of gestational diabetes. Screening and prevention of type 2 diabetes. Literature review

Women with a history of gestational diabetes mellitus (GDM) are characterized by a high risk of type 2 diabetes mellitus (T2DM) (x 7), metabolic syndrome (x 2 to 5) and cardiovascular diseases (x 1,7). Women with lesser degrees of glucose intolerance share the same risks. T2DM may occur from post-partum (5 to 14%) to several years later, up to 25 years. Some factors associated with T2DM are identified: obesity, early diagnosis of GDM before 24 weeks gestation, high pregnancy OGTT blood glucose or insulin-therapy during GDM. Screening for T2DM only with fasting glucose provides less sensibility than with OGTT; HbA1c may supplant these dosages. The recurrence rate of GDM is between 30 and 84%, non-white ethnicity and insulinotherapy during GDM being the best proven predictors. High risk women need repeated life-long screenings for glycaemic abnormalities, or when another pregnancy is planned. Among obese women with history of GDM who show minor glycoregulation disturbances, modifications of lifestyle in intensive programs or metformin halve the risk of DT2. However, studies analysing practices show low adhesion to screening; without an intensive program, few women implement lifestyle modifications. These intensive programs should be implemented and proposed to high-risk women. Their therapeutic education should also include prevention of cardiovascular risk factors.

[Outcomes in women with history of gestational diabetes mellitus. Screening and prevention of type 2 diabetes mellitus. Literature review]

Women with a history of gestational diabetes mellitus (GDM) are characterized by a high risk of type 2 diabetes mellitus (T2DM) (X 7), metabolic syndrome (X 2 to 5) and cardiovascular diseases (X 1,7). Women with lesser degrees of glucose intolerance share the same risks. T2DM may occur from postpartum (5 to 14%) to several years later, up to 25 years. Some factors associated with T2DM are identified: obesity, early diagnostic before 24 weeks, high pregnancy OGTT blood glucose or insulinotherapy. Screening for T2DM only with fasting glucose provides less sensibility than with OGTT; HbA1c may supplant these dosages. The recurrence rate of GDM is between 30 and 84%, non-white ethnicity and insulinotherapy during GDM being the best proven predictors. High risk women need repeated life-long screenings for glycemic abnomalies, or when another pregnancy is planned. Among overweight or obese women with history of GDM who show minor glycoregulation disturbances, it is proved that modifications of lifestyle in intensive programs or metformin halve the risk of DT2. However, studies analysing practices show low adhesion to screening; without an intensive program, few women implement lifestyle modifications. These intensive programs should be implemented and proposed to high-risk women. Their therapeutic education should also include prevention of cardiovascular risk factors.

The "hypertriglyceridemic waist" phenotype and glucose intolerance in pregnancy

BACKGROUND

Abdominal visceral adiposity in early pregnancy has been associated with impaired glucose tolerance in later pregnancy. The "hypertriglyceridemic waist" phenotype (i.e., abdominal obesity in combination with hyper-triglyceridemia) is a clinical marker of visceral obesity. Our study aimed to assess the association between the hyper-triglyceridemic-waist phenotype in early pregnancy and glucose intolerance in later pregnancy.

METHODS

Plasma triglycerides and waist girth were measured at 11-14 weeks of gestation among 144 white pregnant women. Glycemia was measured following a 75-g oral glucose tolerance test performed at 24-28 weeks of gestation.

RESULTS

A waist girth greater than 85 cm in combination with a triglyceride level ≥ 1.7 mmol/L in the first trimester was associated with an increased risk of two-hour glucose ≥ 7.8 mmol/L following the 75-g oral glucose tolerance test (odds ratio [OR] 6.1, p = 0.002). This risk remained significant even after we controlled for maternal age, fasting glucose at first trimester and previous history of gestational diabetes (OR 4.7, p = 0.02).

INTERPRETATION

Measurement of waist girth in combination with measurement of triglyceride concentrations in the first trimester of pregnancy could improve early screening for gestational glucose intolerance.

Beta-cell function declines within the first year postpartum in women with recent glucose intolerance in pregnancy

OBJECTIVE

Both gestational diabetes mellitus (GDM) and mild glucose intolerance in pregnancy identify women at increased risk of future type 2 diabetes. In this context, we queried whether metabolic changes that occur in the 1st year postpartum vary in relation to gestational glucose tolerance status.

RESEARCH DESIGN AND METHODS

Three-hundred-and-ninety-two women underwent glucose challenge test (GCT) and oral glucose tolerance test (OGTT) in pregnancy followed by repeat OGTT at both 3 months' postpartum and 12 months' postpartum. The antepartum testing defined four gestational glucose tolerance groups: GDM (n = 107); gestational impaired glucose tolerance (GIGT) (n = 75); abnormal GCT with normal glucose tolerance (NGT) on OGTT (abnormal GCT NGT) (n = 137); and normal GCT with NGT on OGTT (normal GCT NGT) (n = 73).

RESULTS

The prevalence of dysglycemia progressively increased across the groups from normal GCT NGT to abnormal GCT NGT to GIGT to GDM at both 3 months' postpartum (2.7% to 10.2% to 18.7% to 34.6%, P < 0.0001) and 12 months' postpartum (2.7% to 11.7% to 17.3% to 32.7%, P < 0.0001). Between 3 and 12 months' postpartum, the groups did not differ with respect to changes in waist circumference, weight, or insulin sensitivity. Importantly, however, they exhibited markedly different changes in beta-cell function (Insulin Secretion-Sensitivity Index-2 [ISSI-2]) (P = 0.0036), with ISSI-2 declining in both the GDM and GIGT groups. Furthermore, on multiple linear regression analysis, both GDM (t = -3.06, P = 0.0024) and GIGT (t = -2.18, P = 0.03) emerged as independent negative predictors of the change in ISSI-2 between 3 and 12 months' postpartum.

CONCLUSIONS

Women with GDM and GIGT exhibit declining beta-cell function in the 1st year postpartum that likely contributes to their future diabetic risk.

The risk of overt diabetes mellitus among women with gestational diabetes: a population-based study

AIMS

To determine the incidence of postpartum diabetes mellitus in the years following a diagnosis of gestational diabetes mellitus (GDM) and to determine whether the severity of GDM, represented by the magnitude of the deviation of diagnostic tests from the normal values or requirement for medications, is associated with the development of diabetes.

METHODS

A retrospective cohort study was performed among 185 416 pregnant women who had glucose challenge test or 3 h oral glucose tolerance test (OGTT) in a large health maintenance organization in Israel. Subsequent diagnosis of diabetes was ascertained by using an automated patient registry.

RESULTS

A total of 11 270 subjects were diagnosed with GDM, comprising 6.07% of the cohort. During a total follow-up period of 1 049 334 person-years there were 1067 (16.9 per 1000 person-years) and 1125 (1.1 per 1000 person-years) diagnoses of postpartum diabetes among GDM and non-GDM women, respectively. The cumulative risk of incident diabetes in GDM patients with up to 10 years of follow-up was 15.7%, compared with 1% among the non-GDM population. Gestational diabetes mellitus was associated with nearly an eightfold higher risk of postpartum diabetes after adjusting for important confounders, such as socioeconomic status and body mass index. Among women with a history of GDM, the number of abnormal OGTT values and use of insulin were associated with a substantially higher risk for developing diabetes.

CONCLUSIONS

Three or four abnormal OGTT values and GDM requiring insulin or oral hypoglycaemic medications are important predictors of postpartum diabetes risk in women with a history of GDM.

Glucose intolerance in pregnancy and postpartum risk of metabolic syndrome in young women

CONTEXT/OBJECTIVE

Gestational diabetes mellitus (GDM) and even mild glucose intolerance in pregnancy are both associated with increased risks of developing type 2 diabetes and cardiovascular disease in the future. Because the metabolic syndrome also identifies patients at risk of type 2 diabetes and cardiovascular disease, we hypothesized that gestational dysglycemia may be associated with an unrecognized latent metabolic syndrome. Thus, we sought to evaluate the relationship between gestational glucose tolerance status and postpartum risk of metabolic syndrome.

DESIGN/SETTING/PARTICIPANTS

In this prospective cohort study, 487 women underwent oral glucose tolerance testing in pregnancy and cardiometabolic characterization at 3 months postpartum. The antepartum testing defined three gestational glucose tolerance groups: GDM (n = 137); gestational impaired glucose tolerance (GIGT) (n = 91); and normal glucose tolerance (NGT) (n = 259).

MAIN OUTCOME MEASURE

The primary outcome was the presence of the metabolic syndrome at 3 months postpartum, as defined by International Diabetes Federation (IDF) and American Heart Association/National Heart Lung and Blood Institute (AHA/NHLBI) criteria, respectively.

RESULTS

The postpartum prevalence of IDF metabolic syndrome progressively increased from NGT (10.0%) to GIGT (17.6%) to GDM (20.0%) (overall P = 0.016). The same progression was observed for AHA/NHLBI metabolic syndrome (NGT, 8.9%; GIGT, 15.4%; and GDM, 16.8%; overall P = 0.046). On logistic regression analysis, both GDM (odds ratio, 2.05; 95% confidence interval, 1.07-3.94) and GIGT (odds ratio, 2.16; 95% confidence interval, 1.05-4.42) independently predicted postpartum metabolic syndrome.

CONCLUSIONS

Both GDM and mild glucose intolerance in pregnancy predict an increased likelihood of metabolic syndrome at 3 months postpartum, supporting the concept that women with gestational dysglycemia may have an underlying latent metabolic syndrome.

An application of artificial immune recognition system for prediction of diabetes following gestational diabetes

Diabetes mellitus (DM) is a disease prevalent in population and is not easily perceived in its initial stage but may sway a patient very seriously in later stage. In accordance with the estimation of World Health Organization (WHO), there will be 370 million diabetics which are 5.4% of the global people in 2030, so it becomes more and more important to predict whether a pregnant woman has or is likely to acquire diabetes. This study is conducted with the use of the machine learning-Artificial Immune Recognition System (AIRS)-to assist doctors in predicting pregnant women who have premonition of type 2 diabetes. AIRS is proposed by Andrew Watkins in 2001 and it makes use of the metaphor of the vertebrate immune system to recognize antigens, select clone, and memorize cells. Additionally, AIRS includes a mechanism, limited resource, to restrain the number of memory cells from increasing uncontrollably. It has also showed positive results on problems in which it was applied. The objective of this study is to investigate the feasibility in using AIRS to predict gestational diabetes mellitus (GDM) subsequent DM. The dataset of diabetes has imbalanced data, but the overall classification recall could still reach 62.8%, which is better than the traditional method, logistic regression, and the technique which is thought as one of the powerful classification approaches, support vector machines (SVM).

Mild glucose intolerance in pregnancy and risk of cardiovascular disease: a population-based cohort study

BACKGROUND

Pregnant women commonly receive screening for gestational diabetes mellitus by use of a 50 g glucose challenge test, followed by a diagnostic oral glucose tolerance test for those whose glucose challenge test result is abnormal. Although women with gestational diabetes have an increased risk of cardiovascular disease, it is not known whether mild glucose intolerance during pregnancy is also associated with cardiovascular disease. Thus, we sought to determine whether pregnant women with an abnormal glucose challenge test result but without gestational diabetes have an increased risk of cardiovascular disease.

METHODS

We conducted a retrospective population-based cohort study that included all women in Ontario aged 20-49 years with live deliveries between April 1994 and March 1998. We excluded women with pregestational diabetes. The population was stratified into 3 cohorts: women with gestational diabetes (n = 13,888); women who received an antepartum oral glucose tolerance test (suggestive of an abnormal result of the glucose challenge test) but who did not have gestational diabetes (n = 71,831); and women who did not receive an oral glucose tolerance test (suggestive of a normal result of the glucose challenge test) (n = 349,977). The primary outcome was cardiovascular disease (admission to hospital for acute myocardial infarction, coronary bypass, coronary angioplasty, stroke or carotid endarterectomy).

RESULTS

Compared with women who did not receive an oral glucose tolerance test, women with gestational diabetes and women who received an oral glucose tolerance test but did not have gestational diabetes had a higher risk of cardiovascular disease over 12.3 years of median follow-up (adjusted hazard ratio [HR] for women with gestational diabetes 1.66, 95% confidence interval [CI] 1.30-2.13, p < 0.001; adjusted HR for those with an oral glucose test but not gestational diabetes 1.19, 95% CI 1.02-1.39, p = 0.03).

INTERPRETATION

Mild glucose intolerance in pregnancy may be associated with an increased risk of cardiovascular disease.

An abnormal screening glucose challenge test in pregnancy predicts postpartum metabolic dysfunction, even when the antepartum oral glucose tolerance test is normal

OBJECTIVE

In pregnancy, a normal result on the oral glucose tolerance test (OGTT) that follows an abnormal screening glucose challenge test (GCT) is considered a reassuring finding, requiring no further intervention. The obstetrical and metabolic implications of this presentation, however, have not been well studied. Thus, we sought to characterize the obstetrical and postpartum metabolic significance of an abnormal GCT in women with normal glucose tolerance (NGT) on antepartum OGTT.

DESIGN/PATIENTS/MEASUREMENTS

A total of 259 women with NGT on antepartum OGTT (166 with an abnormal GCT and 93 with a normal GCT) underwent (i) metabolic evaluation in pregnancy, (ii) assessment of obstetrical outcome at delivery and (iii) repeat metabolic characterization by OGTT at 3 months postpartum.

RESULTS

Neither infant birthweight nor Caesarean section rate differed between the abnormal GCT and normal GCT groups. At 3 months postpartum, however, compared to the normal GCT group, the abnormal GCT group exhibited greater glycaemia (mean area under the glucose curve (AUC(gluc)) 19.6 vs. 18.3, P = 0.0021), lower insulin sensitivity (median insulin sensitivity index (IS(OGTT)) 9.5 vs. 11.3, P = 0.0243) and poorer beta-cell function (median insulinogenic index/Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) 9.8 vs. 14.1, P = 0.0013). On multiple linear regression analyses, an abnormal GCT emerged as (i) the strongest independent predictor of postpartum AUC(gluc) (t = 2.77, P = 0.006) and (ii) the strongest independent negative predictor of log insulinogenic index/HOMA-IR (t = -2.36, P = 0.0191). Furthermore, the GCT was the antepartum parameter that best predicted postpartum pre-diabetes (area under the receiver operating characteristic curve (AROC) = 0.754).

CONCLUSIONS

An abnormal antepartum GCT, even when followed by a normal OGTT, is associated with postpartum glycaemia and beta-cell dysfunction, factors that may portend an increased future risk of diabetes in this patient population.

The impact of gestational weight gain and diet on abnormal glucose tolerance during pregnancy in Hispanic women

OBJECTIVE

To examine the association of gestational weight gain and dietary factors with abnormal glucose tolerance (AGT).

METHODS

We conducted a prospective cohort study among 813 Hispanic prenatal care patients in Massachusetts. Gestational weight gain and oral glucose tolerance test results were abstracted from medical records. Dietary intake was assessed using a semi-quantitative food frequency questionnaire. Target weight gain was based on BMI-specific weekly weight gain rates established by the Institute of Medicine (IOM).

RESULTS

We observed a statistically significant interaction between prepregnancy BMI and weight gain in relation to AGT (P < 0.01). Class II/III (BMI > or = 35 kg/m2) obese women who had a high rate of weight gain (>0.30 kg/week) or who exceeded target weight were 3-4 times as likely to develop AGT compared to women who gained within IOM ranges (OR = 4.2, 95% CI 1.1-16.0, OR = 3.2 95% CI 1.0-10.5, respectively). Decreasing levels of saturated fatty acids and energy-dense snack foods and increasing levels of fiber and polyunsaturated:saturated fat ratio were significantly associated with decreased risk of AGT, independent of gestational weight gain [corrected].

CONCLUSIONS

Weight gain among class II/III obese women and certain dietary components may represent modifiable risk factors for AGT.

Abnormal screening glucose challenge test in pregnancy and future risk of diabetes in young women

AIMS

Pregnant women commonly undergo screening for gestational diabetes mellitus (GDM) using a 50-g glucose challenge test (GCT), followed by a diagnostic oral glucose tolerance test (OGTT) in those women in whom the GCT is abnormal. Although it has long been recognized that GDM is associated with subsequent Type 2 diabetes, it has recently emerged that any degree of abnormal antepartum glucose homeostasis predicts an increased risk of postpartum glucose intolerance. Thus, in this context, we sought to determine whether women who have a pregnancy complicated by an abnormal GCT, but who do not have GDM, are at increased risk of subsequent diabetes, compared with their peers with an abnormal GCT.

METHODS

A population-based, retrospective cohort study was conducted. Women referred for an antepartum OGTT indicative of an abnormal GCT (n = 15 381), but without GDM, were matched (for age, region, socioeconomic status, and year of delivery) with up to four other women without such referral (n = 61 237). The two cohorts were followed over a median 6.4 years for the development of diabetes.

RESULTS

The rate of incident diabetes was 5.04 cases per 1000 person-years in the cohort of women who underwent an antepartum OGTT, compared with 1.74 cases per 1000 person-years in women without an OGTT. The hazard ratio for subsequent diabetes in women with an antepartum OGTT was 2.56 (95% confidence interval 2.28, 2.87) (P < 0.0001).

CONCLUSIONS

Even in the absence of GDM, abnormal screening GCT in pregnancy is associated with an increased future risk of diabetes in young women.

Glucose intolerance in pregnancy and future risk of pre-diabetes or diabetes

OBJECTIVE

The purpose of this study was to test the hypothesis that any degree of abnormal glucose homeostasis detected on antepartum screening for gestational diabetes mellitus (GDM) should be associated with an increased risk of postpartum pre-diabetes or diabetes.

RESEARCH DESIGN AND METHODS

In this prospective cohort study, 487 women underwent 1) antepartum GDM screening by a glucose challenge test (GCT) and a diagnostic oral glucose tolerance test (OGTT) and 2) postpartum metabolic characterization by OGTT at 3 months after delivery. Four baseline glucose tolerance groups were defined on the basis of the antepartum GCT/OGTT: 1) GDM (n = 137); 2) gestational impaired glucose tolerance (GIGT) (n = 91); 3) abnormal GCT with normal glucose tolerance on an OGTT (abnormal GCT NGT) (n = 166); and 4) normal GCT with NGT on an OGTT (normal GCT NGT) (n = 93).

RESULTS

The prevalence of postpartum glucose intolerance (pre-diabetes or diabetes) increased across the groups from normal GCT NGT (3.2%) to abnormal GCT NGT (10.2%) to GIGT (16.5%) to GDM (32.8%) (P(trend) < 0.0001). On logistic regression analysis, all three categories of abnormal glucose homeostasis in pregnancy independently predicted postpartum glucose intolerance: abnormal GCT NGT odds ratio (OR) 3.6 (95% CI 1.01-12.9); GIGT OR 5.7 (1.6-21.1); and GDM OR 14.3 (4.2-49.1). Furthermore, both in pregnancy and at 3 months postpartum, insulin sensitivity (IS(OGTT)) and pancreatic beta-cell function (insulinogenic index/homeostasis model assessment of insulin resistance) progressively decreased across the groups from normal GCT NGT to abnormal GCT NGT to GIGT to GDM (all P(trend) < 0.0001).

CONCLUSIONS

Any degree of abnormal glucose homeostasis in pregnancy independently predicts an increased risk of glucose intolerance postpartum.