Validity of WHO Criteria for Classification of Newly Diagnosed Diabetics* 1)

In order to assess the validity of WHO criteria for the discrimination between Type I and Type II diabetes a cross-sectiona clinical study was performed in 84 normweight newly diagnosed diabetics with a mean age of 22 years. Taking into consideration clinical and biochemical characteristics of the carbohydrate and fat metabolism, the therapeutic requirement to maintain euglycemic metabolic control, the residual beta-cell function, the HLA phenotype and islet cell antibodies (ICA, ICSA) it could be shown that none of the tested criteria has the ability to distinguish between the types with absolute certainty. As shown by the frequency of the different markers in relation to the therapeutic requirements for euglycemic metabolic control as well as by the correlation analysis between the variables the discriminating validity of the markers decreased in the following sequence: diabetes associated HLA phenotype, residual beta-cell function, proneness to ketosis, age at onset, relative body weight. Neither the characteristics of the carbohydrate and fat metabolism nor the presence of islet cell antibodies contributed much to the differentiation between insulin-dependent and noninsulin-dependent diabetes.