Estimation of HbA1c response to sitagliptin by change in glycated albumin level for 2 weeks

Abstract

Aims/Introduction: Since glycated albumin (GA) reflects shorter-term (about 2weeks) control of plasma glucose levels compared with HbA1c, GA is thought to be a useful glycemic control indicator for the early period following commencement of the treatment of diabetes. In this study, we attempted to estimate HbA1c using the change in GA level before and after the first 2weeks (ΔGA2w) of administration of sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor. Materials and Methods: The study included 28 patients with type 2 diabetes who were administered sitagliptin at a dose of 50mg/day for 12weeks. Results: At 2weeks after administration of sitagliptin, GA markedly decreased, while HbA1c had only slightly decreased. A significant positive correlation was observed between the ΔGA2w and the change in HbA1c before and after the first 12weeks of administration of sitagliptin (ΔHbA1c12w) (R=0.793, P<0.0001). The latter was about 0.6 times the former. The estimated HbA1c after 12weeks of therapy was calculated by adding ΔGA2w×0.6 to the baseline HbA1c. A significant positive correlation was observed between the estimated HbA1c and the measured HbA1c after 12weeks (R=0.735, P<0.0001) and both were similar levels. Conclusions: HbA1c in the first 12weeks after administration of sitagliptin could be estimated from the formula using the ΔGA2w. © 2011 Asian Association for the Study of Diabetes and Blackwell Publishing Asia Pty Ltd.