Long-term assessment of glucose control by haemoglobin-AGE measurement.
BACKGROUND
Control of blood glucose is important in reducing both the incidence and the severity of complications in diabetes mellitus. One consequence of long- term hyperglycaemia is the formation and accumulation of advanced glycation end-products (AGEs) on tissue macromolecules. An AGE-modified form of human haemoglobin (Hb-AGE) present at high levels in the red cells of diabetic patients, differs from glucose-derived Amadori product HbA1c in being chemically irreversible and thus persisting for the circulating life of the red cell. We therefore compared Hb- AGE with HbA1c as indicators of long-term blood glucose control.


METHODS
In an open study we measured circulating HbA1c and Hb-AGE concentrations in eight patients with poorly controlled non-insulin-dependent diabetes after a switch to subcutaneous insulin therapy and careful blood glucose monitoring.


RESULTS
After 16 weeks of insulin therapy, the mean HbA1c had decreased from 13.3 (SD 1.2) to 7.3 (0.9)% and the mean Hb-AGE from 12.1 (1.5) to 7.3 (1.3) U/mg Hb. The rate of Hb-AGE decline was 23% slower than that of HbA1c (p=0.044).


CONCLUSIONS
The observation that Hb-AGE declines more slowly than HbA1c is consistent with the irreversible nature of the AGE product. Because of this property, Hb-AGE may prove superior to HbA1c as a long-term index of circulating glucose concentrations.
Wolffenbuttel
B H
BH
Division of Endocrinology, University Hospital Maastricht, The Netherlands.
Giordano
D
D
Founds
H W
HW
Bucala
R
R
D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications / Q000188:drug therapy; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D019270:Fructosamine; D006442:Glycated Hemoglobin / Q000378:metabolism*; D017127:Glycation End Products, Advanced / Q000097:blood*; D006595:Hexosamines / Q000097:blood; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged
D001786:Blood Glucose; D019270:Fructosamine; D006442:Glycated Hemoglobin; D017127:Glycation End Products, Advanced; D006595:Hexosamines; D007004:Hypoglycemic Agents; D007328:Insulin