No increase of hypoglycaemia upon transfer of aged longstanding Type 1 diabetic patients to human insulin: A prospective randomized study

To assess the frequency and severity of hypoglycaemia following transfer to human insulin, 94 aged Type 1 diabetic patients on animal insulin were randomly assigned either to continue their usual insulin (group A, n = 48) or convert to equivalent preparations of human insulin (group B, n = 46). At inclusion, the two groups showed no differences in age (58.1 +/- 2.2 vs. 54.4 +/- 2.3 years), duration of diabetes (20.8 +/- 1.4 vs. 19.6 +/- 1.6 years) (mean +/- SEM), and glycosylated haemoglobin (HbA(1c)) values (9.1 +/- 0.2 % vs. 8.9 +/- 0.2 %). There were 43 eligible patients in group A and 41 in group B. After three months of treatment, HbA(1c) values were not significantly different between the two groups (8.6 +/- 0.2 % vs. 8.5 +/- 0.2 %), and there was no difference in the frequency and intensity of hypoglycaemic episodes. Quality of life, as assessed by a questionnaire, was similar at inclusion and after three months. However, the anxiety level was significantly lower in group B. Type 1 diabetic patients were efficiently and safely switched from animal to human insulin without aggravating the incidence of hypoglycaemia, in spite of two major risk factors, i.e. advanced age and diabetes of long duration.