Hemoglobin A1c and postpartum abnormal glucose tolerance among women with gestational diabetes mellitus

Screening of postpartum diabetes in women with gestational diabetes: high-risk subgroups and areas for improvements-the STRONG observational study

AIMS

To assess the proportion of women with gestational diabetes (GDM) by performing postpartum Oral Glucose Tolerance Test (OGTT) and to identify GDM phenotypes at high-risk of postpartum dysglycemia (PPD).

METHODS

Observational, retrospective, multicenter study involving consecutive GDM women. Recursive partitioning (RECPAM) analysis was used to identify distinct and homogeneous subgroups of women at different PPD risk.

RESULTS

From a sample of 2,736 women, OGTT was performed in 941 (34.4%) women, of whom 217 (23.0%) developed PPD. Insulin-treated women having family history of diabetes represented the subgroup with the highest PPD risk (OR 5.57, 95% CI 3.60-8.63) compared to the reference class (women on diet with pre-pregnancy BMI <  = 28.1 kg/m2). Insulin-treated women without family diabetes history and women on diet with pre-pregnancy BMI > 28.1 kg/m2 showed a two-fold PPD risk. Previous GDM and socioeconomic status represent additional predictors. Fasting more than post-prandial glycemia plays a predictive role, with values of 81-87 mg/dl (4.5-4.8 mmol/l) (lower than the current diagnostic GDM threshold) being associated with PPD risk.

CONCLUSIONS

Increasing compliance to postpartum OGTT to prevent/delay PPD is a priority. Easily available characteristics identify subgroups of women more likely to benefit from preventive strategies. Fasting BG values during pregnancy lower than those usually considered deserve attention.

A Review on Research Progress in the Application of Glycosylated Hemoglobin and Glycated Albumin in the Screening and Monitoring of Gestational Diabetes

Glycosylated hemoglobin (HbA1C) and glycated albumin (GA) can be used for blood glucose management of a person with diabetes as a result of their convenience and stability. However, there is no corresponding standard for the application of glycosylated hemoglobin and glycosylated albumin in gestational diabetes mellitus (GDM). In this review, we summarize the published research and discuss three aspects of the significance of HBA1C and GA in GDM patients: screening of gestational diabetes mellitus, blood glucose monitoring and the relationship with pregnancy outcome. At present, studies suggest that HBA1C can be used as a screening indicator for pregnant women, but it cannot completely replace OGTT. HbA1C and GA can be used for blood glucose management in patients with GDM to reduce the incidence of GDM complications. However, the application of HBA1C and GA in GDM still needs more research and clinical practice support.

Effects of metformin and insulin therapy regimens on postpartum oral glucose tolerance test results in pregnant women with gestational diabetes mellitus: a comparative study

OBJECTIVES

The main purpose of this study was to compare the effects of two regimens of metformin and insulin therapy on postpartum oral glucose tolerance test (OGTT) results in pregnant women with gestational diabetes mellitus (GDM).

METHODS

In this single-blind randomized clinical trial (RCT), a total number of 60 pregnant women meeting the inclusion criteria were assigned to two groups with a randomized block design (RBD): insulin therapy (IT) group (30 patients) and metformin therapy (MT) group (30 patients). At baseline, the data were comprised of prenatal maternal age, gestational age, GDM diagnosis, and maternal weight/height. During the postpartum period, 5-cc blood samples were taken from the pregnant women concerned to analyze their fasting blood sugar (FBS) levels. Then, the patients were asked to come back four days and six weeks later after delivery to check the OGTT results. At six weeks postpartum, in addition to OGTT, the glycated hemoglobin (HbA₁C) test was performed for all mothers. Finally, six weeks after delivery, these mothers were evaluated with regard to weight loss and body mass index (BMI).

RESULTS

Six weeks postpartum, the maternal weight and BMI significantly decreased in the MT group compared with the IT one, while there was no significant difference between both groups at baseline. On the fourth day, the OGTT results in the MT group were significantly lower in comparison with those in the IT group (p=0.012). At sixth weeks postpartum, the OGTT results were comparably lower in the MT group than those reported for the IT one; however, such a difference was not statistically significant (p=0.087).

CONCLUSIONS

According to the study results, metformin could be an effective and safe treatment for pregnant women suffering from GDM instead of insulin therapy.

The relationship between total cholesterol and postpartum impaired glucose tolerance in women with gestational diabetes mellitus

Background

History of gestational diabetes mellitus (GDM) and serum lipid abnormalities were associated with postpartum impaired glucose tolerance. To investigate the association between concentration of total cholesterol (TC), at the time of GDM diagnosis, and risk of postpartum glucose intolerance.

Methods

Women who were diagnosed GDM with a live singleton delivery between January 1, 2013 and December 31, 2017 were included. Women were grouped based on the TC quartiles at the time of GDM diagnosis and had an OGTT at 6–12 weeks after delivery. The relationship between TC and the risk of postpartum glucose intolerance was assessed by COX regression.

Results

A total of 845 women were in the final analysis. Higher TC quartile at diagnosis of GDM was associated with a decreased risk of postpartum glucose intolerance. Women in the highest TC quartile (>7.0 mmol L^− 1) had approximately only half-risk of any postpartum glucose intolerance, compared with women in the lowest TC quartile (<5.5 mmol L^− 1).

Conclusions

The decreased concentration of TC, at the time of GDM diagnosis, was related to an increased risk of postpartum abnormal glucose regulation in GDM women. Therefore, because both excessively increased and decreased TC were associated with pregnancy and postpartum complications, the optimal concentration of maternal TC throughout pregnancy remained to be further researched.

One-hour oral glucose tolerance test plasma glucose at gestational diabetes diagnosis is a common predictor of the need for insulin therapy in pregnancy and postpartum impaired glucose tolerance

Aims/Introduction

Gestational diabetes mellitus (GDM) is a risk for adverse perinatal outcomes, and patients with a history of GDM have an increased risk of impaired glucose tolerance (IGT). Here, we carried out two non‐interventional and retrospective studies of GDM patients in Japan.

Materials and Methods

In the first study, we enrolled 529 GDM patients and assessed predictors of the need for insulin therapy. In the second study, we enrolled 185 patients from the first study, and assessed predictors of postpartum IGT.

Results

In the first study, gestational weeks at GDM diagnosis and history of pregnancy were significantly lower, and pregestational body mass index, family history of diabetes mellitus, 1‐ and 2‐h glucose levels in a 75‐g oral glucose tolerance test (OGTT), the number of abnormal values in a 75‐g OGTT, and glycated hemoglobin were significantly higher in participants receiving insulin therapy. In the second study, 1‐ and 2‐h glucose levels in a 75‐g OGTT, the number of abnormal values in a 75‐g OGTT, glycated hemoglobin, and ketone bodies in a urine test were significantly higher in participants with OGT. Logistic regression analysis showed that gestational weeks at GDM diagnosis, 1‐h glucose levels in a 75‐g OGTT and glycated hemoglobin were significant predictors of the need for insulin therapy, and 1‐h glucose levels in a 75‐g OGTT at diagnosis and ketone bodies in a urine test were significant predictors for postpartum IGT.

Conclusions

Antepartum 1‐h glucose levels in a 75‐g OGTT was a predictor of the need for insulin therapy in pregnancy and postpartum IGT.

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.

Patterns of diabetes care in Slovenia, Croatia, Serbia, Bulgaria and Romania : An observational, non-interventional, cross-sectional study

BACKGROUND

National guidelines for treating type 2 diabetes in the Balkans generally follow European guidelines. The current study was undertaken to estimate the rate of glycated hemoglobin (HbA1c) measurements and level of HbA1c control in diabetic patients treated in regular clinical practice settings in the Balkans and to evaluate if providing HbA1c measurements improves adherence to treatment guidelines.

METHODS

This cross-sectional study enrolled type 2 diabetic patients treated by 79 primary care physicians and 102 specialists. The participants were provided with HbA1c measuring devices to measure HbA1c during regular office visits and a physician survey evaluated HbA1c the results feedback. Relevant clinical, demographic, drug treatment and specialist referral data were extracted from patient charts. Descriptive statistics and stepwise multivariate regression analysis were used.

RESULTS

Among 1853 patients included (average age 63.5 ± 10.7 years, 51% male) the average diabetes duration was 8.9 ± 7.1 years, 40% of patients had HbA1c measured every 6 months and 34% every 12 months (or less frequently). The rate of 6‑month measurement was higher among specialists (43%) vs. primary care physicians (32%, p < 0.01). The average HbA1c was 7.3 ± 1.5 and 35% of patients achieved the target HbA1c level of < 6.5%. Metformin monotherapy was prescribed to 28% of patients and metformin + sulphonylurea to 23%, 55% of patients on metformin monotherapy and 32% of patients on dual therapy metformin + sulphonylurea achieved the target HbA1c < 6.5%. Treatment remained unchanged in 91% and was stepped up in only 7.2% of patients. Physicians were not surprised (in 79% of patients) or were pleasantly surprised (in 11%) by the HbA1c results at the time of visit. Average diabetes duration and patient use of home glucometers were associated with the level of disease control.

CONCLUSIONS

The rates of HbA1c measurements remain low in the Balkans, although higher among specialists. Over 60% of patients, mostly treated with traditional oral antidiabetics did not achieve disease control. Providing convenient HbA1c measurement devices was not associated with a marked change in diabetes management. Future research is needed to evaluate the impact of these treatment patterns on long-term outcomes and costs to society.

Measuring glycated haemoglobin in women with gestational diabetes mellitus: How useful is it?

BACKGROUND

Glycated haemoglobin (HbA1c) is an important tool for assessing glycaemic status in patients with diabetes, but its usefulness in gestational diabetes mellitus (GDM), is unclear.

AIMS

The aim of this study is to evaluate whether HbA1c in women with GDM is valuable in predicting adverse pregnancy outcomes.

MATERIALS AND METHODS

A retrospective review of women with GDM who had HbA1c measured at diagnosis of GDM (GHb-diag) and at 36 weeks gestation (GHb-36 weeks) was conducted. The association between HbA1c and various pregnancy outcomes was assessed RESULTS: Among 1244 women with GDM in our cohort, both GHb-diag and GHb-36 weeks were independent predictors for large-for-gestation (LGA) babies (OR 1.06, P = 0.005 and OR 1.06, P = 0.002, respectively) and neonatal hypoglycaemia (OR 1.10, P < 0.001 and OR 1.09, P < 0.001, respectively). Women with HbA1c ≥ 5.4% (35 mmol/mol) at diagnosis had significantly greater risk for LGA (15.3% vs 8.2%, P < 0.001) and neonatal hypoglycaemia (42.2% vs 23.6%, P < 0.001) than those below this cut-off. The difference between GHb-diag and GHb-36 weeks was small and improvement in HbA1c by 36 weeks was not associated with better pregnancy outcomes.

CONCLUSION

We showed that measurement of HbA1c, either at the time of diagnosis of GDM or toward the end of pregnancy, were both associated with adverse pregnancy outcomes. Women with elevated HbA1c (>5.4% or 35 mmol/mol) at diagnosis of GDM should be monitored closely during pregnancy. However, there is not enough evidence to suggest that repeating HbA1c toward the end of pregnancy will provide additional information in predicting adverse pregnancy outcomes.

HbA1c for diagnosis and prognosis of gestational diabetes mellitus

AIMS

HbA1c is a widely used marker in diagnosing type 2 diabetes mellitus (DM), but its clinical utility in diagnosing gestational diabetes mellitus (GDM) is not established. Here, we evaluated the clinical usefulness of HbA1c in diagnosing GDM and predicting the risk of future type 2 DM development among GDM patients.

METHODS

This retrospective, cross-sectional study included 321 subjects who underwent 100-g oral glucose tolerance tests (OGTT) during pregnancy. HbA1c and other variables were analyzed to evaluate their diagnostic performance for GDM. To evaluate the clinical usefulness of HbA1c in predicting future type 2 DM development, we classified GDM subjects who had more than 3 months of follow-up data into two subgroups: those who developed postpartum type 2 DM (PDM) and those who did not.

RESULTS

HbA1c was significantly higher in the GDM group than in the normal control group. With the 100-g OGTT as reference, HbA1c showed 91.3% sensitivity and 62% specificity at a cut-off value of 5.05% (32 mmol/mol) for GDM diagnosis. At a cut-off value of 5.25% (34 mmol/mol), sensitivity was 73.6% and specificity was 77.2%. HbA1c levels during pregnancy were higher in those with PDM than in those without PDM (5.91 [41 mmol/mol] vs. 5.44% [36 mmol/mol], p<0.001). The prognostic value of HbA1c for PDM was evaluated by ROC curve analysis, with sensitivity of 78.6% and specificity of 72.5% at a cut-off value of 5.55% (37 mmol/mol).

CONCLUSIONS

HbA1c showed high sensitivity with relatively low specificity for diagnosis of GDM in pregnant women and was a potential predictor of PDM. HbA1c may be able to be used as a simple and less invasive alternative screening test for OGTT in GDM patients.

Original research: postpartum testing rates among women with a history of gestational diabetes--systematic review

AIMS

Gestational diabetes mellitus (GDM) is increasing and 30% have persistent postpartum dysglycemia. Reported compliance with recommended postpartum testing ranges 9-95% without a clear explanation for this wide variation. Small and conflicting differences in testing rates are associated with some demographics (race, use of insulin), but system factors likely play a larger role. A systematic literature review was performed to identify system based factors that could explain the broad variation in postpartum GDM testing rates.

METHODS

Original articles reporting postpartum testing rates among women with GDM were identified within PubMed, OVID, EMBASE, and the Cochrane Database of systematic reviews. Articles that did not report rates for the entire GDM cohort were excluded.

RESULTS

54/307 citations met inclusion criteria. The use of proactive patient contact programs increased postpartum testing rates from an average of 33% (range 9-71%) up to 60% (range 14-95%).

CONCLUSIONS

Proactively contacting patients via phone calls, education programs, or postal reminders was associated with higher postpartum testing rates. Rather than working to identifying individual demographic factors, systems based approaches were associated with a larger potential impact, and appear easily generalizable. Clinicians should think beyond individual habits and consider systematic approaches to improving testing rates.