Glycation of hair protein in the assessment of long-term control of blood glucose.

Glycation of hair protein was assessed in diabetic patients by the measurement of furosine, which is derived from fructose-lysine, a glycated lysine residue in protein. The level of furosine in 12-cm-long hair which grew over the course of one year was significantly better correlated with the mean values of four determinations of fasting plasma glucose (FPG) and four determinations of hemoglobin A1c (HbA1c) performed at three-month intervals than with FPG and the level of HbA1c, respectively, at the time of hair sampling. The level of glycation in hair, which corresponds to the time taken for hair growth, may represent the mean level of blood glucose during the time corresponding to the growth period. These results suggest that the determination of glycation in hair may be useful as an indicator of long-term control of blood glucose levels if appropriate lengths of hair are taken from the scalp.