Diabetic nephropathy: fault or destiny?

Twenty-one young onset Type 1 (insulin dependent) diabetics who developed severe diabetic nephropathy after 14.5 +/- 3.3 years (mean +/- SD) and 21 age and sex matched Type 1 diabetics without evidence of nephropathy after more than 32 years of disease were compared with particular reference to body build, insulin requirements, stability of diabetes, heart rate and blood pressure before the development of nephropathy. Attempts were made to evaluate the quality of metabolic control during the first 20 years of diabetes from more than 1,600 out-patient measurements of blood and urinary glucose in each group. The renal tubular reabsorption capacity for glucose was calculated in both groups. No differences between the two groups were found for any of the parameters examined, except that the frequency of ketoacidosis was higher in the patients who developed nephropathy. It is concluded that many Type 1 diabetics seem to be protected against the deleterious effect of diabetes on the kidney. The nature of the protecting factors is unknown.