Influence of insulin sensitivity and secretion on glycated albumin and hemoglobin A1c in pregnant women with gestational diabetes mellitus

Objective: To examine the differential effects of insulin sensitivity and secretion on hemoglobin A1c (HbA1c) and glycated albumin (GA) at 24-32 weeks of pregnancy in women with gestational diabetes mellitus (GDM). Methods: A cross-sectional, sequential case series study was performed in pregnant women with an abnormal 50-g oral glucose-screening test. Hemoglobin A1c and GA measurements were taken during oral glucose tolerance test (OGTT). The homeostasis model assessment of insulin resistance (HOMA-IR) and beta-cell function (HOMA-%beta), insulin sensitivity index (ISOGTT), and modified insulinogenic index were calculated to assess insulin sensitivity and secretory function. Results: A total of 713 pregnant women were enrolled. The GDM group had lower ISOGTT and insulinogenic index scores, and a higher HOMA-IR score. Hemoglobin A1c was positively correlated with HOMA-IR. Glycated albumin was negatively correlated with insulinogenic index and HOMA-%beta. Multiple regression analysis revealed that HbA1c was independently associated with diastolic pressure, 0- and 120-minute glucose, and HOMA-IR; GA was independently associated with 0- and 120-minute glucose. Conclusion: Compared with HbA1c, GA is more closely correlated with fasting and postprandial glucose, regardless of insulin resistance and blood pressure, and might be a better monitoring index in women with GDM. (C) 2013 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.