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×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% (48mmol/mol) and 7.0% (53mmol/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 β-cell function (HOMA-β), and ΔI30/ΔG30 (all, P<0.05). Increased glucose at 30min (standardized β=0.221, P<0.001), and decreased BMI (standardized β=-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.