[Studies of nephropathies in 168 diabetic patients with over 20-year onset of the disease].

Within a clinical epidemiological investigation 168 diabetics were examined multidisciplinarily who survived the beginning of their disease by at least 20 years. The qualitative proof of protein in the urine was regarded as criterion for the presence of a diabetic nephropathy. 29% of the long-term diabetics showed a proteinuria. In a control group of probands with healthy metabolism, however, only 2.5% proteinurias were found. Statistically ascertained correlations were the results in cases of proteinuria and retinopathy (microangio-pathy). Particularly close were the relations of proteinuria to arteriolosclerosis (macroangiopathy). There were no relations between the proof of a proteinuria and the quality of the control of the carbohydrate metabolism which was pursued during decades.