[The effect of biguanides on insulin sensitivity of maturity onset diabetics (author's transl)].

The effect of short-term treatment with biguanides on the insulin sensitivity (KITT) of maturity onset diabetics was tested by means of an insulin tolerance test. On the basis of their long-term blood glucose response to biguanide therapy, the patients were classified retrospectively as biguanide-responsive subjects (n = 10) and as biguanide-non-responsive subjects (n = 10). Both group showed the typical marked reduction in insulin sensitivity of maturity onset diabetics. After three days of biguanide treatment, a highly significant (p less than 0.001) increase in insulin sensitivity was noted in the group of biguanide responders, which was significantly (p less than 0.02) correlated with their previous blood glucose response to long-term biguanide therapy. In the biguanide non responders, insulin sensitivity was not significantly altered by biguanides. It is suggested that the blood glucose lowering action of biguanides is due, at least in a definite group of patients with maturity onset diabetes, to a reduction of insulin resistance.