Fructosamine is a time‑averaged indicator of blood glucose levels and is used to assess the glycemic status of diabetics. The concentration of glycated proteins such as glycohemoglobin, glycoalbumin or glycated total protein is generally recognized to be valuable in evaluating the glycemic status of diabetic patients. Measurement of fructosamine may be a suitable alternative to measurement of HbA1c in patients with Hb variants. Various other methods used for such determinations such as affinity chromatography and the thiobarbituric acid method are labor intensive and time consuming and results obtained from different laboratories are difficult to compare.
The turnover of serum proteins (albumin has a half‑life of 19 days) is less than that of hemoglobin (life‑span of erythrocytes is approx. 120 days), and therefore fructosamine determinations provide a means of monitoring patient blood glucose status over a shorter period (1‑3 weeks) than glycohemoglobin (6‑8 weeks). As a result, changes in fructosamine values alert the physician to deteriorating glycemic control earlier than changes in HbA1c values. In addition, fructosamine levels decrease more quickly than HbA1c when diabetic patients are brought under better control.