[Rinsho Byori 51 : 586〜591, 2003]

Diabetes Mellitus and HbA1c

Makoto TOMINAGA, MD*

Since the Japan Diabetes Association(JDS) began to distribute Lot 1 as the primary calibrator for measuring Hemoglobin A1c(HbA1c) to manufactures of reagents and devices in 1995, the standardization of the measurement of HbA1c has been achieved throughout Japan. In 1999, JDS proposed a new diagnostic criterion for diabetes mellitus, and HbA1c was adopted firstly as an assistant index for diagnosis of diabetes mellitus, after HbA1c measurement was standardized by JDS. Furthermore, JDS published a clinical guideline for treatment of diabetes mellitus in 1999, in which it was stated that HbA1c below 6.5% should be one of the goals. This statement was made based on the results of the Kumamoto Study. Because Lot 1 was made mainly in order to minimize the difference among measurements by HPLC devices, Lot 1 is a freeze-dried material. Since some faults of Lot 1 were pointed out after its distribution, in 2001 JDS approved Lot 2 as the new standard material, a deeply frozen material. Currently in Japan, the standardization of HbA1c is maintained with Lot 2.

*Department of Laboratory Medicine, Yamagata University School of Medicine, Yamagata 990-9585