Performance Characteristics of Glycated Albumin and Its Clinical Usefulness in Diabetic Patients on Hemodialysis

Background: The HbA1c has been considered to underestimate glucose level in diabetic patients on hemodialysis, therefore, glycated albumin (GA) was recently introduced to assess the glycemic control for those cases. We evaluated the performance of GA assay kit of Lucica GA-L (Asahi Kasei Pharma Co., Japan) and compare it with HbA1c for estimating glucose levels. Methods : Tests for precision, linearity and interference were performed and reference interval was determined. Thirty eight of non-hemodialysis and seventy of hemodialysis patients were recruited, whose glucose levels of three-, two- and one-month prior to this study were available for calculating weighted means of glucose (WMGs). The correlation coefficients and the slopes of regression equation between WMG and HbA1c or GA were compared between two groups. Multiple linear regression analyses were used to determine significant predictor for HbA1c and GA. Results: Total CV was 2.2% at concentration of 13.7% and 2.8% at 24.6%, The dilution curve between 15.7% and 62.1% was linear. Reference intervals were 10.0% to 16.5% for male and 11.4% to 17.6% for female. The correlation coefficients between WMG and GA were 0.682-0.713 in hemodialysis and 0.640-0.677 in non-hemodialysis. Those between WMG and HbA1c were 0,568-0.625 in hemodialysis and 0.735-0.783 in non-hemodialysis. The slopes of regression equation between GA and WMG in hemodialysis were 0.080-0.090 and 0.130-0.147 in non-hemodialysis. Those between HbA1c and WMG in hemodialysis were 0.012-0.014 and 0.029-0.032 in non-hemodialysis. GA was not influenced by hemodialysis status while HbA1c was. Conclusions: The claimed performance characteristic of Lucica GA-L were verified. WMG were better reflected by GA rather than HbA1c in patients on hemodialysis. (Korean J Lab Med 2009;29:406-14)