Evaluation of metabolic control in type 1 (insulin-dependent) diabetic patients by estimation of serum fructosamine.

The method of Johnson et al. (1982) for the estimation of non-enzymatically glycated serum proteins (fructosamine test) was critically evaluated and modified with respect to photometric readings, incubation conditions, and standardization of the procedure. With this modified method, serum fructosamine concentrations were estimated in type 1 (insulin-dependent) diabetic patients whose glycemic control ranged from strictly to poorly controlled and in normoglycemic healthy control subjects. The mean fructosamine concentrations were for the control group (n = 52) 2.17 mmol/l (range 1.73-2.61 mmol/l) and for the diabetic patients (n = 432) 2.87 +/- 0.60 mmol/l (range 2.27-3.25 mmol/l). There were significant differences in fructosamine concentrations among the diabetic patients, corresponding to the degree of metabolic control. Serum fructosamine levels were closely correlated to the HbA1 levels. Compared with HbA1, fructosamine reflects short-term metabolic changes and appears to be an useful index of short-term glycemia.