Insulin antibodies before and 1 year after the change-over from U40 to U100 insulin preparations in Belgium.

Abstract

In 1991, Belgium realized, on a national level, a change-over from U40 to U100 insulin. We took advantage of this evolution to investigate the consequences of changing the concentration of insulin. The patients' weight, daily insulin dosis, insulin binding-capacity of plasma and glycated hemoglobin HbA1c were registered before, and after the change of concentration. Overall, none of these parameters underwent an obvious change, except for the percentage of insulin binding that significantly decreased after the adaptation. Especially in the range of 40% or more insulin binding, the decrease becomes very pronounced. In conclusion, changing the insulin concentration from U40 to U100, did not lead to any harmful clinical consequence. On the contrary, a positive influence of this adaptation, in terms of decreased amount of insulin antibodies was suggested. Probably this decrease is not clinically relevant, since neither the glycated hemoglobin, nor the total daily insulin dose underwent a similar change.