Background Glycated albumin (GA), which is an alternative glycemic marker, is influenced by factors associated with albumin turnover, and it is not clear whether proteinuria influences GA values in diabetic patients with chronic kidney disease (CKD).
Methods We enrolled 94 diabetic patients with CKD stages 3 to 5. GA, glycated hemoglobin, and urinary protein excretion (UP) levels were consecutively obtained in each patient. The correlations between GA and UP and those between changes in GA and UP were examined.
Results There was a significant correlation between GA and UP in all cases (r=-0.46, p<0.0001), however no significant correlation was found in cases with UP of 0-3.49 g/day (r=0.01). GA values in cases with UP ≥3.5 g/day were significantly lower than those in cases with UP <3.5 g/day [UP ≥3.5 g/day and serum albumin (Alb) ≤3 g/dL; 12.0 ± 1.3%, UP ≥3.5 g/day and Alb >3 g/dL; 17.8 ± 4.3%, 0≥ UP <3.5 g/day; 21.2 ± 4.2%], while no significant difference in HbA_1c or glucose levels was found. In cases with a minimum of UP ≥0.5 g/day, no significant correlation was found between the difference in GA and the difference in UP at the point of maximum UP and minimum UP (r=0.04).
Conclusion Nephrotic-range proteinuria decreases GA values independent of the glycemic state, while non-nephrotic range proteinuria has no significant influence on GA values in diabetic CKD patients.