Reliability of glycosylated hemoglobin in the diagnosis of gestational diabetes mellitus

Predelivery HbA1c levels and their relationship with adverse perinatal outcomes in women with normal 75-g OGTT

PURPOSE

To analyze the elevation of HbA1c before full-term delivery in single pregnancy with normal 75 g- Oral glucose tolerance test (OGTT) screening and its association with adverse perinatal outcomes.

METHODS

From January to December 2022, an observational prospective study was conducted in a Single centre in China. 365 single pregnant women with normal OGTT were included in the study. HbA1c was measured during OGTT and before full-term delivery, and perinatal outcomes were collected. Participants' pre-delivery HBA1c values were analyzed and perinatal outcomes were compared. Logistic regression analysis was used for independent risk factors associated with elevated pre-delivery HbA1c ≥ 6.0%. The predictive value and truncation value were analyzed by ROC curve.

RESULTS

15.89% (58/365) of the Participants had a pre-delivery HBA1C value ≥ 6.0%. The incidence of neonatal asphyxia (13.79%, vs. 3.45%, vs. 2.26%, P = 0.007) and amniotic fluid fecal staining (29.31%, vs. 12.64%, vs. 12.03%, P = 0.004) were significantly increased in this group. The independent risk factor associated with pre-delivery HBA1c ≥ 6.0% was the fasting blood glucose(FBG) value of OGTT (OR = 51.308, 95% CI 12.93-203.67, P < 0.01) and the HBA1c value measured during OGTT (OR = 3.608, 95% CI 1.432-9.151, P = 0.007). When FBG was < 4.18 mmol/L and HBA1c was < 5.51%, The accuracy of predicting the pre-delivery HBA1c < 6.0% was 98.2%.

CONCLUSIONS

15.89% of the single pregnancy with normal OGTT had HbA1c ≥ 6.0% before full-term delivery, and they had an increased incidence of neonatal asphyxia and amniotic fluid fecal staining. When the FBG ≥ 4.18 mmol/l or the HBA1c ≥ 5.51% during the OGTT screening, repeated OGTT were recommended in late pregnancy.

Assessment of Glycemic Control in Patients With Diabetes in Northern Sudan Using Calculated HbA1c

BACKGROUND

Diabetes mellitus (DM) significantly burdens health services worldwide. As a simple and cost-effective method, the mathematical calculation of HbA1c is coming to be of value in areas with scarce resources. This study aimed to use calculated HbA1c to ascertain the prevalence of uncontrolled DM and correlate it with the risk factors for DM.

METHODS

In the River Nile State of northern Sudan, a cross-sectional study was conducted in five leading cities from May to August 2021. Patients diagnosed and recorded as having type 2 or type 1 DM were included in this study. Enzymatic methods were used to assess fasting blood glucose (FBG). We used the mean of three FBG readings for three months to calculate HbA1c using the equation {HbA1c = (FBG mg/dl) x 0.03+2.6}, which was used to compute the estimated mediocre blood sugar over the course of three months.

RESULTS

A total of 2047 diabetic patients from northern Sudan were studied for their DM control. Nearly two-thirds (65.2%) had uncontrolled DM. Of the patients studied, uncontrolled DM was significantly positively associated with older age, history of ischemic heart disease, and being a housewife. Multivariate regression analysis showed significant correlations between uncontrolled DM, an inactive lifestyle, and obesity.

CONCLUSION

The prevalence of uncontrolled DM among known patients with diabetic in northern Sudan is high (65.2%). The inactive lifestyles of housewives and freelance workers, having type 1 DM, and being hypertensive and obese are risk factors significantly associated with uncontrolled DM and its related complications.

The diagnostic model for early detection of gestational diabetes mellitus and gestational diabetic nephropathy

BACKGROUND

Gestational diabetes mellitus (GDM) and gestational diabetic nephropathy (GDN) have become an increasingly serious problem worldwide, which can cause a large number of adverse pregnancy consequences for mothers and infants. However, the diagnosis of GDM and GDN remains a challenge due to the lack of optimal biomarkers, and the examination has high requirements for patient compliance. We aimed to establish a simple early diagnostic model for GDM and GDN.

METHODS

We recruited 50 healthy pregnant (HP), 99 GDM patients, 99 GDN patients at Daping Hospital. Renal function indicators and blood cell indicators were collected for all patients.

RESULTS

Compared with HP, GDM, and GDN patients exhibited significantly higher urea/creatinine ratio and NEU. The diagnostic model1 based on the combination of urea/creatinine ratio and NEU was built using logistic regression. Based on receiver operating characteristic curve analysis, the area under the curve (AUC) of the diagnostic model was 0.77 (0.7, 0.84) in distinguishing GDM from HP, and the AUC of the diagnostic model was 0.94 (0.9, 0.97) in distinguishing GDN from HP. Meanwhile, the diagnostic model2 based on the combination of β2-mG, PLT, and NEU in GDM and GDN patients was built using logistic regression, and the area under the ROC curve (AUC ROC) was 0.79 (0.73, 0.85), which was larger than the individual biomarker AUC.

CONCLUSION

Our study demonstrated that the diagnostic model established by the combination of renal function indicators and blood cell indicators could facilitate the differential diagnosis of GDM and GDN patients.

The role of first-trimester HbA1c in the early detection of gestational diabetes

Background

We aimed to assess the utility of HbA1c in the early detection of gestational diabetes (GDM) in the first trimester.

Methods

This prospective study was performed on 700 pregnant women in the perinatology clinic at a tertiary university hospital from March 2018 to March 2020. For all pregnant women, HbA1c and fasting blood glucose (FBG) levels were examined during the first trimester. Then, a GDM screening test was done within 24–28 weeks of pregnancy using a 100 g oral glucose tolerance test (OGTT) as the gold standard test. The GDM diagnosis was made according to the American Diabetes Association (ADA) criteria. Sensitivity, specificity, positive (PPV), and negative predictive value (NPV) of HbA1c and FBG were calculated using the receiver operating characteristic (ROC) curve.

Results

Of 700 participants, one hundred and fifteen (16.4%) women had GDM. The GDM patients were significantly older and had a higher pre-gestational body mass index and pregnancy weight gain compared to the non-GDM participants. The sensitivity and specificity for ruling out GDM at an HbA1c cut-off value of 4.85% was 92.2 and 32.8%, respectively, with a 95.5% NPV and a 21.2% PPV. Furthermore, sensitivity and specificity for diagnosing GDM at an HbA1c cut-off value of 5.45% was 54.8 and 96.8%, respectively, with a 91.5% NPV and a 76.8% PPV. Using HbA1c could decline OGTT in 40.4% of the pregnant women (28.7% with HbA1c < 4.85 and 11.7% with HbA1c ≥ 5.45%).

Conclusion

It seems that the first-trimester HbA1c cannot replace OGTT for the diagnosis of GDM because of its insufficient sensitivity and specificity. However, women with higher first-trimester HbA1c had a high risk for GDM incidence.

Downregulationof circ_0001578 promotes gestational diabetes mellitus by inducing placental inflammation via the NF-κB and JNKs pathways

Gestational diabetes mellitus (GDM) is one of the most common diseases during pregnancy. Some patients with GDM have adverse pregnancy outcomes. However, the pathogenesis of GDM is very complex and not well understood. In this study, we characterized the expression and functions of a circular RNA, circ_0001578, in GDM. In particular, using qRT-PCR, we verified previous RNA-seq results showing that circ_0001578 is significantly downregulated in the placental villous tissues of pregnant women with GMD. We demonstrated that plasma exosome circ_0001578 expression in the second trimester effectively predicts GDM at 28 weeks. Furthermore, in HTR-8/SVneo trophoblasts, the downregulation of circ_0001578 inhibited proliferation and migration and induced apoptosis. These changes may induce chronic inflammation in the placenta. These effects of circ_0001578 downregulation may be mediated by the upregulation of the NF-κB and JNK pathways, combined with increased expression levels of IL-1, IL-6, IL-8, TNF-α, and CRP. Collectively, the downregulation of circ_0001578 may promote GDM by inducing chronic inflammation in the placenta via the NF-κB and JNK pathways. Furthermore, our findings support that circ_0001578 has potential to serve as an early marker of GDM.

An age matched case-control study on the risk factors for the gestational diabetes mellitus among primiparous women

OBJECTIVES

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy. It is associated with a wide range of short and long term adverse health consequences for both mother and offspring. As we know, the risk factors of the GDM are complex and diverse, and the incidence of GDM is directly correlated with the age and the times of women delivery. In the process of exploring the risk factors of GDM, if the 2 known independent risk factors are unevenly distributed among groups, the effects of other risk factors may be concealed. To avoid the influence of the 2 factors on the research results, we collected primiparous women as the participants through the method of the case-control study of age 1꞉1 paired design. Through this way, we want to provide early intervention for the pregnant women with the high risk factors so as to reduce the possibility of the GDM during the pregnancy and promote the maternal and infant's health.

METHODS

This study was a retrospective study. A total of 2 425 pregnant women were collected as the participants, who accepted the regular prenatal examination or nutrition health guidance in the Department of Obstetrics or Nutrition in the Women and Children's Hospital, School of Medicine, Xiamen University from August 2018 to October 2019. According to the inclusion and exclusion criteria, 2 287 pregnant women were included in the study. Among them, 231 pregnant women with the complete information were collected as a case group because of the abnormal results of the oral glucose tolerance test (OGTT) that executed between the 24th and 28th weeks during the pregnancy. Meanwhile, among the participants with the normal results of the OGTT, 231 pregnant women with the complete information were selected randomly as a control group through the method of the age 1꞉1 paired with the case group. The age range of the all subjects was 22 to 45 (28.82±4.03) years old. We collected their clinical and basic data retrospectively, including the BMI before pregnancy, the level of uric acid, fasting blood glucose, serum lipid index, and glycosylated hemoglobin (HbA1c) in the early pregnancy, the body weight gain before the 13th and 24th weeks during the pregnancy, the times of the abortions, the positive of HBsAg, the family history of diabetes or hypertension etc. The differences in these indexes were compared between the 2 groups. The logistic regression analysis was used to explore the risk factors for GDM and the stratified analysis was used to explore the difference of the body weight gain before the 24th week during the pregnancy between the 2 groups.

RESULTS

The BMI before pregnancy, the uric acid, the fasting blood glucose, the body weight gain before the 13th and 24th weeks during the pregnancy in the GDM group were higher than those in the control group, and the differences were significant (all P<0.05). The LDL level in the early pregnancy of the GDM group was higher than that of the control group, however, the HDL level in the early pregnancy of the GDM group was lower than that of the control group, and the differences were significant (both P<0.05). The rates of the pregnant women in the GDM group with more than 2 abortions, obesity or overweight before pregnancy, the fasting blood glucose in the early pregnancy over 5.1 mmol/L were significantly higher than those in the control group (all P<0.05). With the uptrend of the cut-off point of the body weight gain before the 24th week during the pregnancy, the risk of the GDM was gradually increasing. When the cut-off point reached at 10 kg, the difference was significant (OR=1.988, P=0.004). The level of HDL in the early pregnancy over 1.6 mmol/L was the protective factor for GDM (OR=0.460, P=0.016). Meanwhile, the body weight gain over 10 kg before the 24th week during the pregnancy (OR=1.743, P=0.032), the fasting blood glucose in the early pregnancy over 5.1 mmol/L (OR=3.488, P=0.001), the LDL in the early pregnancy over 2.5 mmol/L (OR=2.179, P=0.032) were the risk factors for the GDM. Among them, the fasting blood glucose in the early pregnancy over 5.1 mmol/L had the greatest impact on the increase of risk for the GDM.

CONCLUSIONS

After excluding the influence of the age, for primiparous women, the higher level of the LDL and the fasting blood glucose in the early pregnancy, the higher possibility to be the GDM. Meanwhile, the pregnant women should control their diet as soon as possible to control the body weight gain within 10 kg before the 24th week during the pregnancy so as to reduce the possibility of being GDM.

The diagnostic indicators of gestational diabetes mellitus from second trimester to birth: a systematic review

BACKGROUND

Gestational diabetes mellitus (GDM) is glucose intolerance first recognised during pregnancy. Both modalities and thresholds of the GDM diagnostic test, the Oral Glucose Tolerance Test (OGTT), have varied widely over time and among countries. Additionally, OGTT limitations include inconsistency, poor patient tolerability, and questionable diagnostic reliability. Many biological parameters have been reported to be modified by GDM and could potentially be used as diagnostic indicators. This study aimed to 1) systematically explore biomarkers reported in the literature as differentiating GDM from healthy pregnancies 2) screen those indicators assessed against OGTT to propose OGTT alternatives.

MAIN BODY

A systematic review of GDM diagnostic indicators was performed according to PRISMA guidelines (PROSPERO registration CRD42020145499). Inclusion criteria were full-text, comprehensible English-language articles published January 2009-January 2021, where a biomarker (from blood, ultrasound, amniotic fluid, placenta) was compared between GDM and normal glucose tolerance (NGT) women from the second trimester onward to immediately postpartum. GDM diagnostic method had to be clearly specified, and the number of patients per study higher than 30 in total or 15 per group. Results were synthesised by biomarkers.

RESULTS

Of 13,133 studies identified in initial screening, 174 studies (135,801 participants) were included. One hundred and twenty-nine studies described blood analytes, one amniotic fluid analytes, 27 ultrasound features, 17 post-natal features. Among the biomarkers evaluated in exploratory studies, Adiponectin, AFABP, Betatrophin, CRP, Cystatin-C, Delta-Neutrophil Index, GGT, TNF-A were those demonstrating statistically and clinically significant differences in substantial cohorts of patients (> 500). Regarding biomarkers assessed versus OGTT (i.e. potential OGTT alternatives) most promising were Leptin > 48.5 ng/ml, Ficolin3/adiponectin ratio ≥ 1.06, Chemerin/FABP > 0.71, and Ultrasound Gestational Diabetes Score > 4. These all demonstrated sensitivity and specificity > 80% in adequate sample sizes (> / = 100).

CONCLUSIONS

Numerous biomarkers may differentiate GDM from normoglycaemic pregnancy. Given the limitations of the OGTT and the lack of a gold standard for GDM diagnosis, advanced phase studies are needed to triangulate the most promising biomarkers. Further studies are also recommended to assess the sensitivity and specificity of promising biomarkers not yet assessed against OGTT.

TRIAL REGISTRATION

PROSPERO registration number CRD42020145499.

The calculated versus the measured glycosylated haemoglobin (HbA1c ) levels in patients with type 2 diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) is a chronic metabolic disorder that is increasing globally. It is associated with chronic complications that are more common among patients with poor glycaemic control. Glycosylated haemoglobin (HbA_1c ) is the gold standard for monitoring glycaemic control. Measurements of HbA_1c are relatively expensive and not available in some remote areas of developing countries.

METHODS

We conducted a cross-sectional study to evaluate the agreement between the calculated and measured HbA_1c levels. The equation to compute the calculated HbA_1c also incorporated the fasting blood glucose (FBG) level and was as follows: HbA_1c  = 2.6 + 0.03 × FBG (mg/dl).

RESULT

We enrolled 290 patients with type 2 DM in this study. Of these, 204 (70.3%) were females and the mean (SD) age was 54.9 (12.8) years. The mean (SD) diabetes duration was 6.8 (5.5) years. There were 211 (72.8%) patients using oral hypoglycaemic agents, 62 (21.4%) were using insulin and 17 (5.9%) were using both insulin and oral hypoglycaemic agents. There was a borderline difference between the mean (SD) calculated and measured HbA_1c levels (p = 0.054). There was a significant correlation between the calculated and measured HbA_1c (r = 0.595, p < 0.001). However, there was no agreement between the calculated and measured HbA_1c . The bias ±SD (limits of agreement) for calculated versus measured HbA_1c was -1.008 ± 2.02% (-5.05, 2.032).

CONCLUSION

Despite the presence of a significant correlation between the calculated and measured HbA_1c , the calculated level has shown an unacceptable agreement with the measured HbA_1c .

Glycaemic Variability and Risk Factors of Pregnant Women with and without Gestational Diabetes Mellitus Measured by Continuous Glucose Monitoring

Background: The aim of the study was to compare the continuous glucose monitoring (CGM)-determined glycaemic variability (GV) of pregnant women with gestational diabetes mellitus (GDM) and without GDM (CG; control group). The secondary aim was to evaluate the association between risk factors of diabetes in pregnancy and parameters of glyceamic control. Methods: Demographic, biometric and biochemical parameters were obtained for pregnant women (20-38 years old) who after an oral glucose tolerance test were examined by 7-day continuous glucose monitoring using a iPro^®2 Professional CGM. Results: The differences in GV between women with GDM and CG compared by total area under glucose curve (total AUC, (mmol·day/L) was statistically significant (p = 0.006). Other parameters of glycaemic control such as mean glucose, standard deviation, coefficient of variation, J-index, % time-above target range 7.8 mmol/L (%TAR), % time-in range 3.5-7.8 mmol/L (%TIR), time-below target range 3.5 mmol/L (%TBR), glycated haemoglobin were not significantly different in the study groups. Risk factors (a family history of diabetes, pre-pregnancy BMI, higher weight gain and age) correlated with parameters of glycaemic control. Conclusions: We found a significant difference in GV of women with and without GDM by total AUC determined from CGM. TIR metrics were close to significance. Our work points at an increased GV in relation to the risk factors of GDM. Pregnant women with risk factors have higher probability of severe GV with its consequences on maternal and fetal health state.

Improved gestational diabetes screening protocol

Objectives

This work aimed to assess the diagnostic validity of two approaches for the screening of gestational diabetes mellitus (GDM) with less discomfort for pregnant women.

Methods

A prospective diagnostic validation study was conducted with 2007 pregnant women. According to risk factors for GDM, women were classified into high-risk and low-risk groups. The current diagnostic procedure, based on oral glucose overload, was followed; simultaneously HbA_1c was tested and an algorithm combining both biomarkers was applied.

Results

In the low-risk group, the Glucose challenge test (GCT) showed a higher area under the curve (AUC 0.953; 95% CI 0.915-0.992) than the HbA_1c test (0.688; 95% CI 0.541-0.834). The best GCT cut-off, 153.5 mg/dL (8.52 mmol/L), showed higher diagnostic validity than that for HbA_1c, 28 mmol/mol (4.75%), and that the algorithm using both tests. In the high-risk group, the GCT showed better diagnostic performance than the HbA_1c and the algorithm; the optimal GCT cut-offs were higher than those recommended in current protocols. 13th week: GCT AUC 0.882 (95% CI 0.843-0.921), HbA_1c AUC 0.624 (95% CI 0.562-0.686), GCT cut-off 140.5 mg/dL (7.8 mmol/L), HbA_1c cut-off 33 mmol/mol (5.15%). 24th week: GCT AUC 0.944 (95% CI 0.925-0.962), HbA_1c AUC 0.642 (95% CI 0.575-0.709), GCT cut-off, 145.5 mg/dL (8.08 mmol/L), HbA_1c cut-off 29 mmol/mol (4.85%).

Conclusions

The GDM diagnostic approach using as the first step the GCT with higher cut-offs showed the best diagnostic validity. Applying these thresholds, 55.6 and 13.7% of 100 g. Oral glucose overloads would have been avoided in low-risk and high-risk pregnant women.

Reliability of glycosylated hemoglobin in the diagnosis of gestational diabetes mellitus

Background

Oral glucose tolerance test (OGTT) performed at 24‐28 weeks gestation is the current recommended method to the diagnosis of gestational diabetes mellitus (GDM). Many recent studies investigating HbA1c in detecting GDM yield different results. There are no published data on HbA1c in the diagnosis of GDM in Sub‐Saharan countries including Sudan.

Methods

A cross‐sectional study was carried out at the antenatal care of Saad Abuelela Maternity Hospital, Khartoum, Sudan during the period from February to November 2018 to assess the reliability of HbA1c in the diagnosis of GDM. GDM was diagnosed according to the International Association of Diabetes and Pregnancy Study Groups using a 75‐g oral glucose tolerance test.

Results

Three hundred and forty‐eight women were enrolled. The mean (SD) of the age, gravidity, and gestational age of the enrolled women were 27.8 (5.6) years, 2.36 (2.2) and 26.26 (2.43) weeks, respectively. Sixty‐eight women (19.5%) had GDM. A poor productively for HbA1c in diagnosis GDM was shown (AUC = 0.62, 95% CI = 0.55‐0.69). At HbA1c level of 4.150%, the sensitivity and specificity of the diagnosis for GDM were 76.51% and 37.85%, respectively. At HbA1c level of 5.850%, the sensitivity and specificity of the diagnosis for GDM were 13.24% and 91.43%, respectively. While there was no significant (Spearman) correlation between fasting blood glucose and HbA1c, there were significant correlations between HbA1c and OGTT 1 and 2 hours of OGTT.

Conclusion

In this study, HbA1c has a poor reliability, insufficient sensitivity or specificity for use to diagnose GDM.