Glycated albumin in pregnancy: reference intervals establishment and its predictive value in adverse pregnancy outcomes

Glycated Albumin and Glycemia in Pregnancy and Postpartum: A Pilot Study

OBJECTIVE

 Percent glycated albumin (%GAlb) is a marker of glycemia over the past 2 to 3 weeks in nonpregnant individuals. Longitudinal changes in %GAlb extending throughout pregnancy and postpartum (PP) have not been described. We aimed to describe levels of %GAlb throughout pregnancy and PP and relationships with glycemia.

STUDY DESIGN

 Fifty women among those in the Study of Pregnancy Regulation of INsulin and Glucose cohort underwent 75-g oral glucose tolerance tests (OGTTs) at a mean of 13 weeks (V1) and 26 weeks (V2) of gestation and 11 weeks' PP. %GAlb was measured on frozen plasma samples.

RESULTS

 Total albumin decreased from V1 to V2 and increased PP to levels higher than at V1. %GAlb declined between V1 and V2 (β = - 0.63% 95% CI [-0.8, -0.6] p < 0.001) and remained stable between V2 and PP (β = - 0.04% [-0.3, 0.2] p = 0.78). Body mass index (BMI) was inversely related to %GAlb in pregnancy (V1: rho = - 0.5, p = 0.0001; V2 rho = - 0.4, p = 0.006), but not PP (rho = - 0.15, p = 0.31). The longitudinal changes in %GAlb persisted after adjusting for BMI. Neither glycemia measurements nor hemoglobin A1c were associated with %GAlb at any time point, and adjustments for BMI did not reveal additional associations.

CONCLUSION

 %GAlb decreases between early and late gestation and remains decreased PP, despite a PP increase in total albumin above early pregnancy values. Given the lack of correlation with OGTT values or A1c, %GAlb is unlikely to be useful in assessing glycemia in pregnant or PP women.

KEY POINTS

· Changes in %GAlb extending to the postpartum period have not been described.. · %GAlb decreases in pregnancy and remains decreased postpartum, despite a postpartum increase in total albumin above early pregnancy values.. · Glycemia measurements nor A1c were associated with %GAlb at any time point, therefore, %GAlb is unlikely to be useful in assessing glycemia in pregnant or postpartum women..

A Longitudinal Study of Plasma Glycated Albumin across Pregnancy and Associations with Maternal Characteristics and Cardiometabolic Biomarkers

BACKGROUND

Glycated albumin (GA) has recently been proposed as a screening marker for diabetes among non-pregnant individuals. However, data on GA during pregnancy are sparse and lacking among women of diverse race/ethnicity. We investigated longitudinal concentrations of GA among multiracial pregnant women in the National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singletons.

METHODS

We quantified GA and cardiometabolic biomarkers using longitudinal plasma samples collected at 10 to 14, 15 to 26 (fasting), 23 to 31, and 33 to 39 gestational weeks from 214 pregnant women without gestational diabetes. We examined the distribution of GA across pregnancy and its association with participants' characteristics including race/ethnicity, pre-pregnancy body mass index (ppBMI), and selected cardiometabolic biomarkers. GA trajectories were estimated using a latent class approach.

RESULTS

Medians (interquartile range) of GA concentrations were 12.1% (10.6%-13.4%), 12.5% (10.7%-13.8%), 12.4% (10.9%-13.5%), and 11.5% (10.4%-12.5%) at 10 to 14, 15 to 26, 23 to 31, and 33 to 39 weeks, respectively. There were no significant differences in the pattern among different race/ethnic groups (P > 0.53). A minority of women exhibited a GA trajectory characterized by a high concentration of GA at 15 to 26 weeks. GA concentrations were inversely related to ppBMI and plasma low-density lipoprotein and triglyceride concentrations, but were not significantly related to hemoglobin A1c, fasting insulin, or glucose over pregnancy.

CONCLUSIONS

In this study of individuals who were normoglycemic before pregnancy, plasma GA concentrations stayed relatively constant over pregnancy, decreasing only in late pregnancy. GA concentrations were inversely related to ppBMI and suboptimal lipid profiles, but did not appear to be a sensitive marker for glucose metabolism in pregnancy.

Progress and indication for use of continuous glucose monitoring in patients with diabetes in pregnancy: a review

Gestational diabetes mellitus is one of the most common endocrine diseases that occur during pregnancy. Disorders of blood glucose metabolism during pregnancy can increase the risk of adverse pregnancy outcomes, such as pregnancy-related hypertension, preeclampsia, eclampsia, miscarriage, macrosomia, and neonatal hypoglycemia. Continuous glucose monitoring (CGM) can safely and effectively monitor blood glucose changes in patients with gestational hyperglycemia, thereby reducing adverse pregnancy outcomes. Hence, this article aimed to provide a comprehensive review of the progress and indications for using CGM in pregnant patients with diabetes. CGM can reduce blood glucose fluctuations and the occurrence of serious hypoglycemia and hyperglycemia events and can provide time in range (TIR). TIR is an important indicator of blood glucose level. Patients with a higher TIR during pregnancy have better gestational outcomes.

Reference intervals for glycated albumin during physiological pregnancy of Europid women: Evidences from a prospective observational study

BACKGROUND AND AIMS

Glycated albumin (GA) may assess glycometabolic control over a short period of time respect to HbA_1c, and its use to screen for gestational diabetes in pregnancy has been suggested. To this regard few data on reference intervals (RI) for GA on Europid women have been collected, only from cross-sectional investigations. Aim of this work has been to collect trimester-specific RI for GA in physiological pregnancies, following a longitudinal prospective study.

METHODS

Forty-five healthy pregnant Europid women have been enrolled for whom a GDM screening test was scheduled at 24-28 weeks, in 5 different Italian centers. Only those negative to the OGTT were included. The women had 4 successive visits at 6-10 weeks of gestation, at 16-18 weeks, at 24-28 weeks and at the end of pregnancy. ALT, AST, total bilirubin, C-reactive protein, cholinesterase, creatinine, GGT, glycated albumin, iron, total serum proteins, transferrin were measured in duplicate on aliquots of serum samples by a central laboratory.

RESULTS

The RI (2.5-97.5 percentiles) for GA were 11.1-14.8 % (I visit), 10.9-15.6 % (II visit), 10.6-14.1 % (III visit) and 10.7-14.3 % (IV visit). The RI of other biomarkers confirmed previously published data. The RI for serum cholinesterase we present are novel, and were 5049-9906 U/L (Iv), 4212-8965 U/L (IIv), 3518-8470 U/L (IIIv) and 3945-8727 U/L (IVv).

CONCLUSIONS

Trimester-specific RI are important for using GA and serum cholinesterase in pregnancy. However, considering the high inter-individual variability of both markers, the use of longitudinal interpretations of the individual variations of both proteins during pregnancy should be preferred.

Performance of glycated albumin as a biomarker of hyperglycemia in pregnancy: Results from the National Health and Nutrition Examination Survey 1999-2004

AIM

We sought to evaluate the performance of glycated albumin (GA) as a measure of hyperglycemia in pregnant women.

METHODS

We used data from 555 pregnant women aged 20-40 years who participated in NHANES 1999-2004 and did not report a pre-pregnancy diagnosis of diabetes. We used Pearson's correlations and evaluated the area under the curve (AUC) for GA to detect elevated concentrations of random glucose, HbA1c, or fasting glucose (subset). We compared results to 1607 nonpregnant women aged 20-40 without diabetes.

RESULTS

In pregnant women, 1.9 % had HbA1c ≥ 39 mmol/mol (≥5.7 %), 9.1 % had random glucose ≥ 5.3 mmol/L (≥95 mg/dL), and 10.7 % had fasting glucose ≥ 5.3 mmol/L. In pregnancy, GA was poorly correlated with HbA1c (r = 0.08) and random glucose (r = 0.17). BMI was positively associated with HbA1c (r = 0.33) and random glucose (r = 0.25) but was inversely associated with GA (r = -0.27). GA had poor discrimination for detecting hyperglycemia in pregnant women, defined as HbA1c ≥ 39 mmol/mol (AUC = 0.634) or random glucose ≥ 5.3 mmol/L (AUC = 0.628). Similar patterns were observed among nonpregnant women.

CONCLUSIONS

GA is not a sensitive test to screen for hyperglycemia in pregnancy. GA was inversely associated with adiposity in pregnant women without diabetes. Pregnancy-related weight gain may complicate interpretation of repeated GA measurements.

Fetal glycated albumin levels in offspring of obese women

OBJECTIVE

To determine the association between maternal obesity and fetal glycated albumin (GA) levels among pregnant women.

METHODS

A comparative, cross-sectional study of 59 consenting, normoglycemic, pregnant women, who met the criteria for maternal obesity, attending the antenatal clinic of the University College Hospital, Nigeria, from June 2019 to December 2019. They were recruited at 36 weeks of gestation, followed up until delivery, and compared with 58 nonobese, normoglycemic pregnant controls. At delivery, blood samples were taken from the mothers and from the umbilical cords of their newborns for serum GA assay. Maternal and newborn variables were recorded, and comparisons were made using χ² tests, independent t tests, odds ratios, analysis of variance, and Pearson correlates. Statistical significance was set at P < 0.05.

RESULTS

The odds of elevated newborn GA were 3.21 times higher in obese women compared with nonobese women (P = 0.005) and 5-min APGAR scores were higher in the newborns of nonobese women (P = 0.039). There was a significant correlation between maternal and neonatal GA for all participants (r = 0.346, P = 0.000).

CONCLUSION

These findings suggest that maternal obesity is associated with elevated fetal GA and low APGAR scores at 5 min in normoglycemic women.

Role of liver parameters in diabetes mellitus - a narrative review

Diabetes mellitus is characterized by hyperglycemia and abnormalities in insulin secretion and function. This review article focuses on various liver parameters, including albumin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), alpha fetoprotein (AFP), alpha 1 antitrypsin (AAT), ammonia, bilirubin, bile acid, gamma-glutamyl transferase (GGT), immunoglobulin, lactate dehydrogenase (LDH), and total protein. These parameters play significant roles in the development of different types of diabetes such as type 1 diabetes (T1DM), type 2 diabetes (T2DM) and gestational diabetes (GDM). The article highlights that low albumin levels may indicate inflammation, while increased ALT and AST levels are associated with liver inflammation or injury, particularly in non-alcoholic fatty liver disease (NAFLD). Elevated ALP levels can be influenced by liver inflammation, biliary dysfunction, or bone metabolism changes. High bilirubin levels are independently linked to albuminuria in T1DM and an increased risk of T2DM. Elevated GGT levels are proposed as markers of oxidative stress and liver dysfunction in T2DM. In GDM, decreased serum AFP levels may indicate impaired embryo growth. Decreased AFP levels in T2DM can hinder the detection of hepatocellular carcinoma. Hyperammonemia can cause encephalopathy in diabetic ketoacidosis, and children with T1DM and attention deficit hyperactivity disorder often exhibit higher ammonia levels. T2DM disrupts the regulation of nitrogen-related metabolites, leading to increased blood ammonia levels. Bile acids affect glucose regulation by activating receptors on cell surfaces and nuclei, and changes in bile acid metabolism are observed in T2DM. Increased LDH activity reflects metabolic disturbances in glucose utilization and lactate production, contributing to diabetic complications. Poor glycemic management may be associated with elevated levels of IgA and IgG serum antibodies, and increased immunoglobulin levels are also associated with T2DM.

Glycated albumin in pregnancy: LC-MS/MS-based reference interval in healthy, nulliparous Scandinavian women and its diagnostic accuracy in gestational diabetes mellitus

Glycated albumin (GA) may be a useful biomarker of glycemia in pregnancy. The aim of this study was to establish the reference interval (RI) for GA, analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), in healthy, nulliparous pregnant women. In addition, we assessed the accuracy of GA and glycated hemoglobin A1c (HbA1c) in the diagnosis of gestational diabetes mellitus (GDM). Finally, we explored the prevalence of GDM in healthy nulliparas, comparing three diagnostic guidelines (WHO-1999, WHO-2013 and the Norwegian guideline). The study was carried out at Stavanger University Hospital, Norway, and included a study population of 147 pregnant nulliparous women. An oral glucose tolerance test (OGTT) was performed and used as the gold standard for GDM diagnosis. Blood samples for analysis of GA and HbA1c were collected at pregnancy week 24-28. A nonparametric approach was chosen for RI calculation, and receiver operating characteristic (ROC) curves were used to evaluate the diagnostic performance of GA and HbA1c. The established RI for GA in 121 pregnant women was 7.1-11.6%. The area under the ROC curves (AUCs) were 0.531 (GA) and 0.627 (HbA1c). According to the WHO-1999, WHO-2013 and the Norwegian guideline, respectively, 24 (16%), 36 (24%) and 21 (14%) women were diagnosed with GDM. Only nine women (6%) fulfilled the GDM-criteria of all guidelines. In conclusion, we established the first LC-MS/MS-based RI for GA in pregnant women. At pregnancy weeks 24-28, neither GA nor HbA1c discriminated between those with and without GDM. Different women were diagnosed with GDM using the three guidelines.

Preliminary reference intervals of Glycated Albumin in healthy Caucasian pregnant women

BACKGROUND AND AIMS

Glycated albumin (GA) could represent a useful biomarker in pregnant women for diagnosing and monitoring gestational diabetes mellitus (GDM). The establishment of reference intervals (RI) is mandatory before assessing its clinical usefulness. The RIs of GA in healthy pregnant women are not well defined. The aim of the current study was to establish the RI in a cohort consisting of Caucasian pregnant women without overt diabetes mellitus or gestational diabetes mellitus.

METHODS

The study included 183 healthy pregnant women. GA was measured on plasma by an enzymatic method (quantILab Glycated Albumin, IL Werfen, Germany). The RI was calculated by the non-parametric and robust methods.

RESULTS

The RI of GA in the whole population was 10.16% (90%CI 9.60-10.70) and 15.44% (90%CI 14.90-16.90). GA levels decreased during pregnancy, with lower levels in the third trimester: 10.11 (90%CI 9.48-10.79) and 15.72 (90%CI 15.15-16.27) in the first trimester, 10.49 (90%CI 10.05-10.96) and 15.49 (90%CI 15.05-15.92) in the second trimester, 9.84 (90%CI 9.50-10.22) and 14.57 (90%CI 14.11-15.01) in the third trimester. Finally, a weak negative correlation was found between GA levels and body mass index.

CONCLUSION

This is the first study establishing the RIs of GA in Caucasian healthy pregnant women.