Serum fructosamine in the assessment of glycaemic control in diabetes mellitus.

Serum fructosamine determination was evaluated in the assessment of glycaemic control in diabetes mellitus. Intra- and inter-assay variation of the method was 0.5-0.8 and 1.5-2.9%, respectively. The fructosamine concentration in serum was found to be stable for at least 10 days independent of prevailing serum glucose concentration is stored at +4 degrees C or colder. Stability of serum fructosamine with respect to rapid fluctuations of blood glucose was of the same order as that of HbA1c. The reference interval (mean +/- 2 SD) for 92 non-diabetic individuals was 1.9-2.7 mmol/l. Good correlation was found between HbA1c and serum fructosamine (r = 0.79). Serum fructosamine and HbA1c correlated well with the mean blood glucose values of the preceding week (r = 0.88 and 0.75, respectively, p less than 0.001). Significant correlations of fructosamine and HbA1c with fasting blood glucose were also found (r = 0.53 and 0.55, respectively, p less than 0.001). Fructosamine determined simultaneously with fasting blood glucose in 65 oral glucose tolerance tests (OGTT) did not separate normal subjects from those with impaired glucose tolerance. Two of the three subjects with diabetic response in the OGTT had, however, elevated fructosamine concentrations. Determination of serum fructosamine is a technically simple, reproducible and moderately inexpensive method for the assessment of glycaemic control in diabetes mellitus. Standardization of the method is, however, not without problems. Uniformity of the calibration and assay protocol is essential for reliable interlaboratory comparison of results. Physiological states altering the rate of synthesis or elimination of serum proteins should be considered in the interpretation of fructosamine levels.(ABSTRACT TRUNCATED AT 250 WORDS)