Abstract
New diagnostic criteria were proposed by the “National Diabetes Data Group” of NIH in 1979 for the purpose of international standardization of the diagnosis of diabetes mellitus. In Japan, the diagnostic criteria proposed by the Japan Diabetic Society for 50g OGTT have been widely popularized. In the present study, we compared the responses of the plasma glucose and insulin concentrations during OGTTs with 50g and 75g loads in subjects with normal or slightly impaired glucose tolerance, and also compared the two sets of diagnostic criteria.
The following results were obtained.
(1) In normal subjects, the plasma glucose responses during the OGTTs were almost identical with 50g and 75g loads, while in subjects with slightly impaired glucose tolerance, the plasma glucose responses during 75g OGTT were higher than those during 50g OGTT and the plasma glucose value at 120 min was statistically higher.
(2) A few subjects with proven diabetic retinopathy have been overlooked by being classified as mild cases according to the criteria proposed by the “National Diabetes Data Group” of NIH.
(3) Taking a plasma glucose level of greater than or equal to 210 mg/dl at 1 hr, and also of greater than or equal to 140mg/dl at 2 hr during 50g OGTT as a new definition of the diabetic state, the results of 50g OGTT appear to be compatible with the new criteria for diabetes mellitus of NIH employing 75g OGTT.
