Metabolic control with insulin pump therapy: the Waikato experience

Aim To report the effect of insulin pump therapy on glycaemic control and on hypoglycaemia and ketosis rates in Type 1 diabetic patients. Methods A retrospective audit of the management of patients with Type 1 diabetes treated with insulin pump therapy at the Waikato Diabetes Service (Hamilton, New Zealand) between September 1997 and December 2004. Results The data of 105 patients currently on continuous subcutaneous insulin infusion (CSII) at the time of data collection were examined. CSII use had occurred for a mean of 3.0 +/- 2.6 years. HbA(1c)% improved significantly from 8.9 +/- 1.3% to 7.9 +/- 1.0% (P<0.001) at 3 months and 7.9 +/- 0.95% (P<0.001) at 6 months post CSII. This reduction was maintained after 1, 2, and 3 years and the difference was statistically significant (P<0.001). In the adolescent subgroup (n=27) we observed a similar significant reduction in HbA1c% that was maintained after 1 year of pump therapy. The incidence of severe hypoglycaemia was reduced from 0.75 cases per patient-year during multiple daily injection (MDI) pre-pump to 0.05 cases per patient-year during CSII (P<0.001). In some cases hypoglycaemia awareness was restored. There was no evidence to suggest increased tendency for diabetic ketoacidosis (DKA) with continuing use of insulin pumps. Conclusion Our experience showed that insulin pump therapy was effective and safe for both adults and adolescents with Type 1 diabetes. The reduction in HbA(1c)% was both statistically and clinically highly significant. Wider usage of this technology in New Zealand is warranted.