Glycated albumin as a surrogate marker for prediabetes: a cross-sectional study

Abstract

Objective Oral glucose tolerance test (OGTT) and glycated haemoglobin (HbA1c) have many limitations in diagnosing prediabetes. Glycated albumin (GA) estimation can be a potential tool for its early diagnosis. The present study aims to analyze the diagnostic efficacy of GA to identify prediabetes. Methods Prediabetics (n = 406) and healthy (n = 406) subjects were included. OGTT was used as the diagnostic standard for identifying prediabetes. HbA1c was estimated in a Bio-Rad D-10 analyzer based on the High-Performance Liquid Chromatography (HPLC) method. GA was measured using the enzyme-linked immunosorbent assay (ELISA) technique and was expressed as a percent of total albumin. Total albumin was measured by the modified bromocresol Purple (BCP) dye-binding method in Siemen's autoanalyzer. Results HbA1c (5.83 +/- 0.57%) and GA (14.43 +/- 1.92%) were significantly higher (p < 0.05) in the prediabetics as compared to healthy individuals. Both HbA1c and GA showed a significantly positive correlation with fasting plasma glucose (FPG) and 2-h plasma glucose. However, the correlation was stronger with 2-h plasma glucose for both parameters. GA and HbA1c also showed a significant positive correlation with each other. HbA1c, at 5.7% cut-off, predicted prediabetes with 74% sensitivity and 90% specificity. At the cut-off of 13.5%, GA showed 66% sensitivity and 85% specificity to identify pre-diabetes. The sensitivity of the combined tests was significantly greater than that for HbA1c alone (84% combined versus 74% HbA1c). Conclusion GA, combined with HbA1c, can be used as a screening test for identifying pre-diabetes. Early diagnosis and interventions could prevent disease progression and limit dreadful complications.