Effect of anti-insulin antibodies on glycemic control in insulin treated diabetic patients.

In order to examine the effect of anti-insulin antibodies on serum insulin concentration and glycemic control, sera from 49 insulin-treated diabetic patients (20 males and 29 females) were examined for their titer of anti-insulin antibodies, and concentrations of total insulin (TIRI), free insulin (FIRI) and hemoglobin A1c. Titer of anti-insulin antibodies correlated only with TIRI (r = 0.72, p less than 0.001) and did not correlate with duration of insulin treatment, FIRI concentration, daily dose of insulin, or HbA1c concentration. These results indicate that elevated titer of anti-insulin antibodies in patients under insulin therapy, increases total serum insulin concentration but does not affect serum free insulin level, and has little effect, if any, on glycemic control and the required daily dose of insulin.