Comparison of single- and split-dose insulin regimens with 24-hour monitoring

It has been asserted that twice daily injections of mixed insulin provide better blood glucose control than one. To compare the two regimens we conducted a random-order, double-crossover trial in ten diabetic children. Each regimen lasted for six weeks, concluding with a hospital evaluation. Control at home was assessed by a urine log and determination of glycosylated hemoglobin. Control in the hospital was assessed with measurements of quantitative urinary glucose, serum lipids, and by 24-hour blood sampling for glucose, C-peptide, and counterregulatory hormones. For the group as a whole, none of the indices of control demonstrated a significant advantage for either regimen. Individually, several children did appear to achieve better control on one regimen than the other. Indices of control at home did not consistently predict control in the hospital. In the hospital, the largest increases in glucose concentration followed breakfast (mean rise 148 mg/dl), and standardized exercise invariably reduced plasma glucose values (mean decrement 60 mg/dl). C-Peptide concentrations were low, but higher values were associated with better control. Although a split insulin regimen may improve metabolic control in some patients, this study did not demonstrate a substantial advantage for the majority of subjects over the short period of the trials.