Dissociation of serum fructosamine from fasting plasma glucose or hemoglobin A1c in diabetics.

To evaluate serum fructosamine as an indicator for diabetic control, serum fructosamine (FRA), glycosylated hemoglobin (HbA1c) and fasting plasma glucose (FPG) were simultaneously measured in 452 diabetics in stable diabetic control. We divided the measured FRA according to the degree of deviation from the expected FRA into three types, hyper-FRA, normo-FRA and hypo-FRA. In the hypo-FRA to HbA1c group, frequencies of male (70 vs 35, 43%) and of nephropathy (61 vs 30, 18%) were higher and mean total serum protein (6.5 vs 7.4, 7.4 g/dl) and albumin (3.4 vs 4.1, 4.0 g/dl) were lower than those in the other two corresponding groups. Correlation was also poorer in the insulin-treated group than the others. These results probably reflect conditions of diabetic control and complication, and protein metabolism. Similar tendencies were observed in case of FPG. Therefore, the discrepancy of FRA gives a clue to detect poor control and complications of diabetes.