Diabetes mellitus following gestational diabetes: role of subsequent pregnancy

Diabetes mellitus in pregnancy across Canada

BACKGROUND

Contemporary estimates of diabetes mellitus (DM) rates in pregnancy are lacking in Canada. Accordingly, this study examined trends in the rates of type 1 (T1DM), type 2 (T2DM) and gestational (GDM) DM in Canada over a 15-year period, and selected adverse pregnancy outcomes.

METHODS

This study used repeated cross-sectional data from the Canadian Institute of Health Information (CIHI) hospitalization discharge abstract database (DAD). Maternal delivery records were linked to their respective birth records from 2006 to 2019. The prevalence of T1DM, T2DM and GDM were calculated, including relative changes over time, assessed by a Cochrane-Armitage test. Also assessed were differences between provinces and territories in the prevalence of DM.

RESULTS

Over the 15-year study period, comprising 4,320,778 hospital deliveries in Canada, there was a statistically significant increase in the prevalence of GDM and T1DM and T2DM. Compared to pregnancies without DM, all pregnancies with any form of DM had higher rates of hypertension and Caesarian delivery, and also adverse infant outcomes, including major congenital anomalies, preterm birth and large-for-gestational age birthweight.

CONCLUSION

Among 4.3 million pregnancies in Canada, there has been a rise in the prevalence of DM. T2DM and GDM are expected to increase further as more overweight women conceive in Canada.

Risk factors associated with the need for insulin in patients with gestational diabetes in a reference hospital in Buenos Aires, Argentina: retrospective cohort study

Objectives

To describe the clinical and sociodemographic characteristics of pregnant women diagnosed with gestational diabetes mellitus (GDM) and to assess factors potentially associated with out-of-target glycemic control and the need for insulin.

Materials and methods

Retrospective descriptive cohort. Women with GDM delivered at a reference hospital between January 2018 and September 2020 were included; women delivered in a different institution were excluded. Measured variables were age, body mass index (BMI) at the start of pregnancy, family history of diabetes, gestational age at the time of diagnosis, blood glucose levels at baseline and following oral glucose tolerance test, fructosamine, Hba1c, and insulin therapy use. A descriptive exploratory analysis of factors associated with poor glycemic control was conducted using uni and multivariate analyses.

Results

Of the patients with GDM, 44 % were out of target for blood glucose with lifestyle and dietary measures. The exploratory analyses revealed a potential increase in the risk of poor glycemic control associated with initial blood glucose level on OGTT (raw OR: 3.57; 95 % CI: 2.1 - 6.1), BMI > 25 kg/m2 (OR: 1.97, 95 % CI: 1.15 - 3.34), and more advanced gestational age at the time of diagnosis as a protective factor against the need for insulin therapy (OR: 0.45, 95 % CI: 0.27- 0.75). However, these associations were not confirmed in the multivariate analysis.

Conclusions

A baseline blood glucose value greater than 95 mg/dl and BMI of more than 25 kg/m2 could be associated with poor glycemic control in women with GDM. Studies that assess these variables and control for confounding factors are needed in order to identify the factors associated with insulin requirement in pregnant women.

Characteristics of pregnancy with gestational diabetes mellitus and the consecutive pregnancy as predictors for future diabetes mellitus type 2

AIM

To explore possible obstetrical history-related, modifiable risk factors of future type 2 diabetes mellitus (T2DM), with focus on characteristics of the index gestational diabetes mellitus (GDM) pregnancy and the consecutive pregnancy.

METHODS

This retrospective, population-based, cohort study included 788 women with GDM, who had consecutive deliveries at Emek Medical Center during 1991-2012. Women with pre-existing diabetes were excluded. Factors associated with T2DM development were examined using stepwise multiple Cox regression model.

RESULTS

Overall 178 women developed T2DM (23%). Multivariable analysis demonstrated that the most significant independent risk factors for T2DM development were birth weight ≥ 4000 g (HR_adj1.7 95% CI [1.001-2.8]), fasting oral glucose tolerance test value (OGTT, HR_adj1.03 95% CI [1.01-1.04], 1-hour post-OGTT glucose value (HR_adj1.01 95% CI [1.006-1.02]), earlier gestational week in which GDM was diagnosed (HR_adj 0.96 95% CI [0.93-0.99]), higher parity (HR_adj 1.15 95% CI [1.06-1.25] and GDM recurrence in the consecutive delivery (HR_adj2.4 95% CI [1.6-3.7]). Kaplan Meier survival curve of the time from the consecutive pregnancy until T2DM development showed a statistically significant effect of GDM recurrence and the risk for T2DM. Body mass index (BMI) gain between pregnancies and inter-pregnancy interval were not independent risk factors for T2DM.

CONCLUSIONS

Obstetric characteristics of women with GDM and particularly GDM recurrence are associated with increased risk for T2DM. Strategies to prevent those factors and especially GDM recurrence might reduce the risk of future T2DM.

Autocrine IGF2 programmes β-cell plasticity under conditions of increased metabolic demand

When exposed to nutrient excess and insulin resistance, pancreatic β-cells undergo adaptive changes in order to maintain glucose homeostasis. The role that growth control genes, highly expressed in early pancreas development, might exert in programming β-cell plasticity in later life is a poorly studied area. The imprinted Igf2 (insulin-like growth factor 2) gene is highly transcribed during early life and has been identified in recent genome-wide association studies as a type 2 diabetes susceptibility gene in humans. Hence, here we investigate the long-term phenotypic metabolic consequences of conditional Igf2 deletion in pancreatic β-cells (Igf2βKO) in mice. We show that autocrine actions of IGF2 are not critical for β-cell development, or for the early post-natal wave of β-cell remodelling. Additionally, adult Igf2βKO mice maintain glucose homeostasis when fed a chow diet. However, pregnant Igf2βKO females become hyperglycemic and hyperinsulinemic, and their conceptuses exhibit hyperinsulinemia and placentomegalia. Insulin resistance induced by congenital leptin deficiency also renders Igf2βKO females more hyperglycaemic compared to leptin-deficient controls. Upon high-fat diet feeding, Igf2βKO females are less susceptible to develop insulin resistance. Based on these findings, we conclude that in female mice, autocrine actions of β-cell IGF2 during early development determine their adaptive capacity in adult life.

First pregnancy risk factors and future gestational diabetes mellitus

PURPOSE

Gestational diabetes mellitus (GDM) affect about 17% of all pregnancies and is associated with significant short- and long-term health consequences for the mother and her offspring. Early diagnosis and prompt interventions may reduce these adverse outcomes. We aimed to identify first pregnancy characteristics as risk factors for GDM in subsequent pregnancy.

MATERIALS AND METHODS

A population-based nested case-control study was conducted in a large tertiary hospital. The study population included all women with two singleton consecutive pregnancies and deliveries, without GDM in the first pregnancy. Characteristics and complications of the first pregnancy were compared among cases and controls. A multivariable logistic regression model was used to study the association between pregnancy complications (in the first pregnancy) and GDM in the subsequent pregnancy, while adjusting for confounding variables.

RESULTS

A total of 38,750 women were included in the study, of them 1.9% (n = 728) had GDM in their second pregnancy. Mothers with GDM in their second pregnancy were more likely to have the following first pregnancy complications: hypertensive disorders, perinatal mortality, maternal obesity and fetal macrosomia. Results remained significant after adjustment for maternal age and inter-pregnancy interval. Having either one of the complications increased the risk for GDM by 2.33 (adjusted OR = 2.33; 95% CI 1.93-2.82) while a combination of two complications increased GDM risk by 5.38 (adjusted OR = 5.38; 95% CI 2.85-10.17).

CONCLUSIONS

First pregnancy without GDM complicated by hypertensive disorders, perinatal mortality, maternal obesity and fetal macrosomia was associated with an increased risk for GDM in the subsequent pregnancy. Women with these complications may benefit from early detection of GDM in their subsequent pregnancy.

Risk Factors for Progression From Gestational Diabetes to Postpartum Type 2 Diabetes: A Review

Gestational diabetes mellitus (GDM) complicates 6% to 8% of pregnancies and up to 50% of women with GDM progress to type 2 diabetes mellitus (DM) within 5 years postpartum. Clinicians have little guidance on which women are most at risk for DM progression or when evidence-based prevention strategies should be implemented in a woman's lifecycle. To help address this gap, the authors review identifiable determinants of progression from GDM to DM across the perinatal period, considering prepregnancy, pregnancy, and postpartum periods. The authors categorize evidence by pathways of risk including genetic, metabolic, and behavioral factors that influence progression to DM among women with GDM.

No deleterious effect of an additional pregnancy on glucose metabolism in women with previous gestational diabetes mellitus

OBJECTIVE

Women with gestational diabetes mellitus (GDM) often develop type 2 diabetes later in life. It remains unclear whether this results solely from a common underlying predisposition or, whether a pregnancy itself persistently impairs glucose metabolism in predisposed women. We therefore examined how an additional pregnancy affected different aspects of glucose metabolism in women with previous GDM.

RESEARCH DESIGN AND METHODS

Nested case-control study within the prospective cohort study PPSDiab, recruited in Munich, Germany from 2011-16. Cases (n = 41): women with previous GDM who completed an additional pregnancy; controls: no additional pregnancy, pairwise matching.

ENDPOINTS

change of the area under the glucose curve (AUGC) of an oral glucose tolerance, of plasma glucose at 60' of the test (PG 60'), of the insulin sensitivity index (ISI) and of the disposition index (DI), all between before and after the additional pregnancy in cases/the corresponding observation period in controls.

RESULTS

We observed no significant difference between cases and controls in the primary [ratio AUGC 1.05(0.92-1.15) vs. 0.97(0.85-1.14); p = 0.21] and in the secondary endpoints [difference PG 60', ratio ISI and ratio DI.

CONCLUSION

We did not find a deleterious effect of an additional pregnancy on glucose metabolism in women with previous GDM.

The impact of educational attainment on the occurrence of gestational diabetes mellitus in two successive pregnancies of Finnish primiparous women: a population-based cohort study

AIMS

To assess the impact of educational attainment on the occurrence and recurrence of gestational diabetes mellitus (GDM) in two successive pregnancies in primiparous women.

METHODS

This is a population-based observational cohort study including all 2347 Finnish women without previously diagnosed diabetes, aged ≥ 20 years from the city of Vantaa, Finland, who gave birth to their first and second child between 2009 and 2015. National registries provided data on study participants. We divided the population into four groups according to the presence of GDM in the two pregnancies (GDM-/-, n = 1820; GDM-/+, n = 223; GDM+/-, n = 113; GDM+/+, n = 191).

RESULTS

The occurrence of GDM in the first pregnancy was 13.0% (n = 304) and 17.6% (n = 414) in the second. The recurrence rate of GDM was 62.8%. The four groups did not differ in relation to educational attainment (p = 0.11). In multinomial regression analysis, educational attainment protected from GDM in the second pregnancy [relative risk ratio 0.93 (95% confidence interval (CI) 0.86-0.99) per year of schooling for being GDM-/+ compared with GDM-/-]. In multivariate logistics models, prepregnancy body mass index at the first pregnancy [odds ratio (OR) 1.53 per 1-standard deviation (SD) (95% CI 1.22-1.91)], first-born birth weight z-score [OR 1.30 per 1-SD (95% CI 1.00-1.67)], and inter-pregnancy weight change [OR 1.66 per 1-SD (95% CI 1.27-2.16)], but not educational attainment, predicted recurrence of GDM.

CONCLUSIONS

The recurrence rate of GDM was high. Education protected from novel GDM in the second pregnancy, but was not associated with GDM recurrence.

Interrupting the Pathway from Gestational Diabetes Mellitus to Type 2 Diabetes: The Role of Primary Care

OBJECTIVE

Our objective was to describe patient-, provider-, and health systems-level factors associated with likelihood of obtaining guideline-recommended follow-up to prevent or mitigate early-onset type 2 diabetes after a birth complicated by gestational diabetes mellitus (GDM).

METHODS

This study presents a retrospective cohort analysis of de-identified demographic and health care system characteristics, and clinical claims data for 12,622 women with GDM who were continuously enrolled in a large, national U.S. health plan from January 31, 2006, to September 30, 2012. Data were obtained from the OptumLabs Data Warehouse. We extracted 1) known predictors of follow-up (age, race, education, comorbidities, GDM severity); 2) novel factors that had potential as predictors (prepregnancy use of preventive measures and primary care, delivery hospital size); and 3) outcome variables (glucose testing within 1 and 3 years and primary care visit within 3 years after delivery).

RESULTS

Asian ethnicity, higher education, GDM severity, and delivery in a larger hospital predicted greater likelihood of post-GDM follow-up. Women with a prepregnancy primary care visit of any type were two to three times more likely to receive postpartum glucose testing and primary care at 1 year, and 3.5 times more likely to have obtained testing and primary care at 3 years after delivery.

CONCLUSIONS

A history of use of primary care services before a pregnancy complicated by GDM seems to enhance the likelihood of postdelivery surveillance and preventive care, and thus reduce the risk of undetected early-onset type 2 diabetes. An emphasis on promoting early primary care connections for women in their early reproductive years, in addition to its overall value, is a promising strategy for ensuring follow-up testing and care for women after complicated pregnancies that forewarn risk for later chronic illness. Health systems should focus on models of care that connect primary and reproductive/maternity care before, during, and long after pregnancies occur.

After Gestational Diabetes: Impact of Pregnancy Interval on Recurrence and Type 2 Diabetes

The contribution of pregnancy interval after gestational diabetes (GDM) to type 2 diabetes (T2DM) onset is a poorly understood but potentially modifiable factor for T2DM prevention. The purpose of this study was to assess the impact of GDM recurrence and/or delivery interval on follow-up care and T2DM onset in a sample of continuously insured women with a term livebirth within 3 years of a GDM-affected delivery. This is a secondary analysis of a cohort of 12,622 women with GDM, 2006–2012, drawn from a national administrative data system (OptumLabs Data Warehouse). We followed 1091 women with GDM who had a subsequent delivery within 3 years of their index delivery. GDM recurred in 49.3% of subsequent pregnancies regardless of the interval to the next conception. Recurrence tripled the odds of early T2DM onset within 3 years of the second delivery. Women with GDM recurrence had greater likelihood of glucose testing in that 3-year interval, but not transition to primary care for continued monitoring, as required by both American Congress of Obstetricians and Gynecologists (ACOG) and the American Diabetes Association (ADA) guidelines. In multivariable analysis, we found a trend toward increased likelihood of T2DM onset for short interpregnancy intervals (≤1 year vs. 3 year, 0.08). Pregnancy interval may play a previously unrecognized role in progression to T2DM. T2DM onset after GDM can be prevented or mitigated, but many women in even this insured sample did not receive recommended follow-up monitoring and preventive care, even after a GDM recurrence. The postpartum visit may be an ideal time to inform patients about T2DM prevention opportunities, and discuss potential benefits of optimal spacing of future pregnancies.

Mothers with HIP - The short term and long-term impact, what is new?

Hyperglycemia is one of the most common medical conditions that women encounter during pregnancy and it is due to gestational diabetes (GDM) in the majority of cases (International Diabetes Federation, 2015) [1]. GDM is associated with a higher incidence of maternal morbidity in pregnancy in term of hypertensive disorders/preclampsia and higher rate of cesarean delivery but also with long-term risk of type 2 diabetes and cardiovascular disease. Pregnancy can therefore be considered a stress test; diagnosis of HIP can unmask a preexisting susceptibility and consequently a future risk for type 2 diabetes and can be a useful marker of future cardiovascular risk. Postpartum follow up provides an excellent opportunity to implement healthy lifestyle behaviors to prevent or delay the development of diabetes or cardiovascular disease. The aim of the current review is to focus on short and long term maternal morbidity of HIP.

Ethnic predisposition of diabetes mellitus in the patients with previous history of gestational diabetes mellitus: a review

INTRODUCTION

The worldwide prevalence of Gestational Diabetes Mellitus (GDM) is increasing day by day. However, there is a knowledge gap regarding the effect of ethnic and geographical distribution on the risk of developing Diabetes Mellitus (DM) in women with history of GDM. This review was conducted to find out the role of ethnic and geographical distribution on the risk of developing DM is women with GDM.

AREAS COVERED

In this review we conducted a comprehensive search of published studies through different electronic databases (PubMed, Google Scholar, CINAHL, CINAHL plus and EMBASE) published between 1990 and 2017. The studies which were published in English investigated the risk of development of DM in women with previous history of GDM, reported outcome according to ethnicity with specific criteria of reporting DM and GDM, reported development of diabetes after 6 month of delivery in women with GDM during pregnancy were included. Initially, 350 articles were identified, among which 16 articles were included in the final review.

EXPERT COMMENTARY

Studies showed the increased risk of developing subsequent DM is associated with precedent GDM. Around 7-84% women developed diabetes after GDM in five years follow up, where some studies reported the risk continues to increase with increasing age. Risk of DM was found higher for some specific ethnicities, irrespective of the location of the study conducted. East Indian women showed the highest risk of postpartum DM after GDM and the crude prevalence remained almost similar in all form of study worldwide. Public health programme should focus more on women belonging to high-risk ethnicity of GDM for the prevention of postpartum DM.

Neonatal delivery weight and risk of future maternal diabetes

OBJECTIVE

To investigate associations between neonatal delivery weight and future risk of maternal type 1 or type 2 diabetes.

METHODS

Data included in the Swedish Medical Birth Registry and Swedish National Diabetes Registry were merged to include all women born during 1930-1989; patients with pre-existing diabetes or gestational diabetes were excluded. Cox regression analyses were performed to identify associations between the neonatal delivery weight from the most recent pregnancy and later occurrence of diabetes.

RESULTS

There were 1 873 440 patients included in the analyses. An increased risk of type 1 (hazard ratio 3.60, 95% confidence interval [CI] 3.23-4.01) or type 2 diabetes (hazard ratio 2.77, 95% CI 2.68-2.87) was observed among patients who had a large for gestational age neonate compared with patients who had neonates within one standard definition of the mean weight for gestational age; the odds of developing type 1 (odds ratio 10.27, 95% CI 7.37-14.31) or type 2 diabetes (odds ratio 8.50, 95% CI 6.01-12.02) within 1 year of delivery was also increased compared with patients who had a neonate within one standard deviation of the mean weight for gestational age.

CONCLUSIONS

Delivering a large for gestational age neonate was a potent risk factor for the later development of maternal type 1 or type 2 diabetes.

Post-partum follow-up of women with gestational diabetes mellitus: effectiveness, determinants, and barriers

BACKGROUND

Despite the recommendations for postpartum blood glucose monitoring post gestational diabetes mellitus (GDM); scientific evidence reveals that these recommendations may not be fully complied to. This study aimed to follow-up women up to 2 years post-delivery with pregnancies complicated by GDM and healthy controls to assess this fact.

METHODS

Women with GDM (n = 78) and normal glucose tolerant (n = 89) delivered in 2014 were followed up for 2 years. They were informed and enquired via telephone about their blood glucose screening, physical activity, postpartum complications, and current weight status of mother and baby.

RESULTS

Women with previous GDM were older and reported higher body weight 2 years post-delivery. At the 2 year follow-up, n = 11 (14.1%) participants had developed diabetes, all with previous GDM. Both weight at birth (3.8 ± 0.5 kg) and at 2-year (10.7 ± 2.3 kg) for the babies born to GDM mothers was significantly higher than the NGT group babies (2.6 ± 0.63 and 7.1 ± 1.4 kg; p < .05). Only 27 women regularly opted for T2DM screening via monitoring blood glucose or HbA1c levels postpartum. The top reason for failed screening included: believing that GDM would disappear after delivery, and being occupied with the baby.

CONCLUSIONS

The high incidence of T2DM in women with previous GDM is an alarming finding. Given this trend, systematic follow-up programs are needed to reduce obesity and diabetes risk.

Quantification of the type 2 diabetes risk in women with gestational diabetes: a systematic review and meta-analysis of 95,750 women

AIMS/HYPOTHESIS

Women with gestational diabetes mellitus (GDM) are at risk of developing type 2 diabetes, but individualised risk estimates are unknown. We conducted a meta-analysis to quantify the risk of progression to type 2 diabetes for women with GDM.

METHODS

We systematically searched the major electronic databases with no language restrictions. Two reviewers independently extracted 2 × 2 tables for dichotomous data and the means plus SEs for continuous data. Risk ratios were calculated and pooled using a random effects model.

RESULTS

There were 39 relevant studies (including 95,750 women) BMI (RR 1.95 [95% CI 1.60, 2.31]), family history of diabetes (RR 1.70 [95% CI 1.47, 1.97]), non-white ethnicity (RR 1.49 [95% CI 1.14, 1.94]) and advanced maternal age (RR 1.20 [95% CI 1.09, 1.34]) were associated with future risk of type 2 diabetes. There was an increase in risk with early diagnosis of GDM (RR 2.13 [95% CI 1.52, 3.56]), raised fasting glucose (RR 3.57 [95% CI 2.98, 4.04]), increased HbA1c (RR 2.56 [95% CI 2.00, 3.17]) and use of insulin (RR 3.66 [95% CI 2.78, 4.82]). Multiparity (RR 1.23 [95% CI 1.01, 1.50]), hypertensive disorders in pregnancy (RR 1.38 [95% CI 1.32, 1.45]) and preterm delivery (RR 1.81 [95% CI 1.35, 2.43]) were associated with future diabetes. Gestational weight gain, macrosomia in the offspring or breastfeeding did not increase the risk.

CONCLUSIONS/INTERPRETATION

Personalised risk of progression to type 2 diabetes should be communicated to mothers with GDM.

SYSTEMATIC REVIEW REGISTRATION

www.crd.york.ac.uk/PROSPERO CRD42014013597.

Factors in Gestational Diabetes Mellitus Predicting the Needs for Insulin Therapy

Objective. To identify factors predicting the need for insulin therapy in pregnancies complicated by gestational diabetes mellitus (GDM). Methods. A total of 1352 patients with GDM diagnosed by the 75-g/2-h oral glucose tolerance test (OGTT) were enrolled in this study. Univariate and multivariate analysis were performed; receiver operating characteristics (ROC) were also drawn. Results. There was a significant difference in factors such as maternal age, pregestational BMI, first visit SBP, first visit DBP, FBG of first visit, FBG at time of OGTT, 75-g OGTT glucose value (fasting, after 1 h and 2 h), and serum HbA1c level at diagnosis between patients with insulin therapy and patients with medical nutrition therapy (MNT) alone. Multivariate analysis showed that higher FBG at time of OGTT, first 75 g OGTT 2 h plasma glucose, and HbA1c concentration at diagnosis lead to more likely need of insulin therapy. Conclusion. The probability of insulin therapy can be estimated in pregnant women with GDM based on fasting and 2 h glucose values during OGTT and HbA1c value at diagnosis of GDM.

The prevalence of gestational diabetes mellitus recurrence--effect of ethnicity and parity: a metaanalysis

Reports on the gestational diabetes mellitus (GDM) recurrence rate have been highly variable. Our objectives were to examine the possible causes of GDM recurrence rate variability and to obtain pooled estimates in subgroups. We have carried out a systematic review and metaanalysis based on the Metaanalysis Of Observational Studies in Epidemiology statement. We identified papers published from 1973 to September 2014. We identified papers using Medline (PubMed and Ovid), ClinicalTrials.gov and Google Scholar databases, and published references. We included only English-language, population-based studies that reported specified GDM criteria and GDM recurrence rate. A total of 18 eligible studies with 19,053 participants were identified. We used the Cochrane's Q test of heterogeneity to choose the model for estimating the pooled GDM recurrence rate. Metaregression was also used to explore the possible causes of variability between studies. The pooled GDM recurrence rate was 48% (95% confidence interval, 41-54%). A significant association between ethnicity and GDM recurrence rate was found (P = .02). Non-Hispanic whites had lower recurrence rate compared with other ethnicities (39% and 56%, respectively). Primiparous women had a lower recurrence rate compared with multiparous women (40% and 73%, respectively; P < .0001) No evidence for association between family history of diabetes and GDM recurrence was found. The overall GDM recurrence rate is high. Non-Hispanic whites and primiparous women have substantially lower GDM recurrence rates, which contributes to the variability between studies. Because no association between family history of diabetes and GDM recurrence was found, the large differences between ethnic groups may have also resulted from nongenetic factors. Thus, intervention programs could reduce the GDM recurrence rates.

The risk factors and incidence of type 2 diabetes mellitus and metabolic syndrome in women with previous gestational diabetes

BACKGROUND

Gestational diabetes mellitus (GDM) affects nearly 5% of pregnancies. Significant proportion of the women with previous GDM develops type 2 diabetes mellitus (T2DM) in the next years, which indicates a higher risk in them than in the general population.

OBJECTIVES

We conducted this study to determine the risk factors and incidence of abnormal glucose level and metabolic syndrome (MetS) in women with a history of GDM in a long period after delivery in our region.

PATIENTS AND METHODS

We extracted the demographic characteristics of 110 women with GDM who had delivered during 2004 - 2010 in three main hospitals of Zanjan City, Iran. The patients were recalled to perform oral glucose tolerance test (OGTT) and other necessary tests for MetS diagnosis. Anthropometric measurements were recorded of all the participants.

RESULTS

In this study, 110 women with a history of GDM were studied at one to six years since delivery. Among these women, 36 (32.7%) developed T2DM and 11 (10%) had impaired fasting glucose (IFG) or impaired glucose tolerance (IGT). Moreover, 22 women (20%) had developed MetS. among those with abnormal results in glycemic test, 93.6% had fasting blood sugar (FBS) ≥ 95 mg/dL (≥ 5.27 mmol/L)at the time of GDM diagnosis in the index pregnancy that was significantly higher than the normal glycemic test (NGT) group with 42.9% being affected (OR, 19.55; P < 0.0001). There was a significant difference between those with abnormal results and NGT group in interval between delivery and performing laboratory tests (27 ± 18.8 and 18.5 ± 17.7 months, respectively; OR, 1.02; P = 0.02). No insulin use during pregnancy was discovered as a protective factor in women with a history of GDM (OR, 0.35; P = 0.01). Those with abnormal results were significantly different from NGT group in the number of parities (2.61 ± 1.4 vs. 2.05 ± 1.1, respectively; OR, 1.4; P = 0.03). The most common component of MetS among women with a history of GDM was FBS > 100 mg/dL (> 5.55 mmol/L).

CONCLUSIONS

Regarding the high incidence of the T2DM and MetS among women with a history of GDM, they should be screened at a regular interval for diabetes and other cardiovascular risk factors.

The impact of recurrent gestational diabetes on maternal metabolic and cardiovascular risk factors

OBJECTIVE

The development of overt diabetes in women with prior gestational diabetes mellitus (priorGDM) has been linked to several risk factors including age, obesity and insulin therapy during pregnancy; the role of recurrent GDM as a further risk factor remains unclear. As studies examining detailed metabolic consequences of recurrent GDM are missing and the role of recurrent GDM on cardiovascular risk is unknown, our aim was to investigate the impact of recurrent GDM (within 5 years after an index pregnancy) on metabolic and cardiovascular parameters.

METHODS

Oral and intravenous glucose tolerance tests as well as assessment of cardiovascular risk factors were performed at baseline (6 months after index pregnancy) and 5 years thereafter in 21 prior GDM with recurrent GDM (recGDM), 41 prior GDM with no additional pregnancy (nonrecGDM) and 10 healthy controls [CON].

RESULTS

Despite weight gain in recGDM (2·3 ± 5·1 vs. -1·3 ± 6·7 kg, P < 0·04), glucose tolerance, insulin sensitivity and secretion did not differ compared with nonrecGDM at baseline and follow-up. Furthermore, recGDM did not exhibit increased cardiovascular risk factors. Metabolic deterioration in (19% of) the total priorGDM group was associated with decreased insulin sensitivity (OGIS:367·4 ± 89·6 vs. 436·4 ± 75·5 mL/min*m², P = 0·01), hyperinsulinaemia (TIS:37·9 ± 9·7 vs. 28·0 ± 10·2 nM, P < 0·006) and postchallenge hyperglycaemia at 5 years postpartum.

CONCLUSIONS

Recurrence of gestational diabetes was not associated with deterioration of glucose metabolism, insulin sensitivity and secretion nor with increased cardiovascular risk. Consequently, priorGDM should not be recommended to refrain from subsequent pregnancies, but be encouraged to regain and maintain normal body weight after delivery and regularly undergo OGTTs to early detect metabolic deterioration.

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.

Factors predicting the need for insulin therapy in patients with gestational diabetes mellitus

AIM

To determine the possible factors predicting the insulin requirement in pregnancies complicated by gestational diabetes mellitus (GDM).

METHOD

A total of 294 patients with GDM diagnosed by the 100-g/3-h oral glucose tolerance test (OGTT) were studied. The following factors were analyzed: maternal age, nulliparity, family history of diabetes, prepregnancy BMI, prior GDM, prior fetal macrosomia, multiple pregnancy, polyhydramnios, gestational age at diagnosis of GDM, smoking, hypertension, number of abnormal 100-g/3-h OGTT values, and glycated hemoglobin (HbA1c). The association between each factor and the need for insulin therapy was then analyzed individually. The performance of these factors to predict the probability of insulin therapy was estimated using a logistic regression model.

RESULTS

Univariate analysis showed a positive correlation between insulin therapy and prepregnancy BMI, family history of diabetes, hypertension, prior GDM, prior fetal macrosomia, number of abnormal 100-g/3-h OGTT values, and HbA1c (P<0.05). Prepregnancy BMI, family history of diabetes, number of abnormal 100-g/3-h OGTT values and HbA1c were statistically significant variables in the logistic regression model.

CONCLUSIONS

The probability of insulin therapy can be estimated in pregnant women with GDM based on prepregnancy BMI, family history of diabetes, number of abnormal 100-g/3-h OGTT values, and HbA1c concentration.

Risk of development of diabetes mellitus after diagnosis of gestational diabetes

BACKGROUND

It is generally appreciated that gestational diabetes is a risk factor for type 2 diabetes. However, the precise relation between these 2 conditions remains unknown. We sought to determine the incidence of diabetes mellitus after diagnosis of gestational diabetes.

METHODS

We used a population-based database to identify all deliveries in the province of Ontario over the 7-year period from Apr. 1, 1995, to Mar. 31, 2002. We linked these births to mothers who had been given a diagnosis of gestational diabetes through another administrative database that records people with diabetes on the basis of either physician service claims or hospital admission records. We examined database records for these women from the time of delivery until Mar. 31, 2004, a total of 9 years. We determined the presence of diabetes mellitus according to a validated administrative database definition for this condition.

RESULTS

We identified 659 164 pregnant women who had no pre-existing diabetes. Of these, 21 823 women (3.3%) had a diagnosis of gestational diabetes. The incidence of gestational diabetes rose significantly over the 9-year study period, from 3.2% in 1995 to 3.6% in 2001 (p < 0.001). The probability of diabetes developing after gestational diabetes was 3.7% at 9 months after delivery and 18.9% at 9 years after delivery. After adjustment for age, urban or rural residence, neighbourhood income quintile, whether the woman had a previous pregnancy, whether the woman had hypertension after the index delivery, and primary care level before the index delivery, the most significant risk factor for diabetes was having had gestational diabetes during the index pregnancy (hazard ratio 37.28, 95% confidence interval 34.99-40.88; p < 0.001). Age, urban residence and lower income were also important factors. When analyzed by year of delivery, the rate of development of diabetes was higher among the latest subcohort of women with gestational diabetes (delivery during 1999-2001) than among the earliest subcohort (delivery during 1995 or 1996) (16% by 4.7 years after delivery v. 16% by 9.0 years).

INTERPRETATION

In this large population-based study, the rate of development of diabetes after gestational diabetes increased over time and was almost 20% by 9 years. This estimate should be used by clinicians to assist in their counselling of pregnant women and by policy-makers to target these women for screening and prevention.