Relationship between glycated albumin and glycated hemoglobin according to glucose tolerance status: A multicenter study

Aims: To determine the relationship between glycated albumin (GA) and glycated hemoglobin (HbA1c) and to explore the association of glycated albumin/glycated hemoglobin (GA/HbA1c) ratio with glucose indices in Chinese subjects with varying glucose tolerance status. Methods: This hospital-based, cross-sectional study involved 953 participants without known diabetes from 11 centers in China. Oral glucose tolerance test (OGTT) was used to identify three groups of subjects: normal glucose regulation (n = 194), impaired glucose regulation (n = 303) and newly diagnosed type 2 diabetes group (n = 456). The GA, HbA1c and GA/HbA1c ratio were tested. Results: GA was positively correlated with HbA1c (r = 0.832, P < 0.001). After correcting for age, sex and BMI, the correlations remained significant (r = 0.824, P < 0.001). Linear regression analysis estimated that a 1% increase of HbA1c was associated with a 2.84% increase of GA (GA = 2.843 x HbA1c - 0.203; R-2 = 0.692, P < 0.001). GA would be 18.3 (16.7-19.9)% and 19.7 (18.0-21.4)% with HbA1c of 6.5% (48 mmol/mol) and 7.0% (53 mmol/mol). The mean GA/HbA1c ratio was 2.81 +/- 0.38, and it significantly increased with the presence of glucose intolerance (all, P < 0.05). In the total study population, GA/HbA1c was correlated with BMI, glucose levels and 30-min insulin during OGTT, the homeostatic model assessment of beta-cell function (HOMA-beta), and Delta I-30/Delta G(30) (all, P < 0.05). Increased glucose at 30 min (standardized beta = 0.221, P < 0.001), and decreased BMI (standardized beta = -0.114, P = 0.008) were associated with elevated GA/HbA1c ratio by multiple linear regression (adjusted R-2 = 0.045). Conclusions: The relationship between GA and HbA1c was strong. The GA/HbA1c ratio was related to acute postprandial glucose fluctuation and BMI level. (C) 2016 Elsevier Ireland Ltd. All rights reserved.