A correlation between microalbuminuria and anti-insulin antibodies in type I diabetics

A link between circulating anti-insulin antibodies and diabetic glomerulopathy has been suggested. This paper presents two different studies aiming to detect a relationship between incipient nephropathy (indicated by microalbuminuria) and anti-insulin antibodies. In 64 type I diabetics, overnight urinary albumin excretion during an exercise-test was found to be correlated with systolic blood pressure (r = 0.258 p less than 0.05), anti-insulin antibodies (r = 0.258 p less than 0.05), and glycosylated hemoglobin (r = 0.258 p less than 0.05) whereas no correlation was found among these three parameters. In another group of 80 type I diabetics, urinary albumin excretion during a standardized exercise-test was also correlated with anti-insulin antibodies (r = 0.360 p less than 0.001). In this latter group, diabetics with elevated (greater than 200 microU/ml) levels of anti-insulin antibodies had higher values of microalbuminuria after exercise (p less than 0.001) when compared to those with lower or undetectable levels, although they did not differ with respect to blood pressure and glycemic control. Therefore, we confirm preliminary reports indicating a statistical relationship between anti-insulin antibodies and microalbuminuria. We hypothesize that anti-insulin antibodies may be an additional factor of risk in the pathogenesis of early (reversible) stages of diabetic nephropathy.