Implantable insulin pumps. A position statement about their clinical use

Abstract

Aim To review clinical use of implantable insulin pumps and to suggest indications for this therapy. Methods The EVADIAC group performed a review of published reports on implantable insulin pumps for the last 15 years and analyzed its own centralized database. From this update, a position statement on indications of this therapy is drawn. Results Published papers mostly report safety and effectiveness data from observational cumulated experiences of 15–350 patient-years. While HbA 1c reduction does not reach statistical significance in all reported studies, improvement of blood glucose stability and reduction of severe hypoglycaemia appear as constant characteristics of this therapy. When compared to subcutaneous insulin therapy in randomized controlled studies, implantable pumps allow significantly reduced blood glucose fluctuations and improved quality of life in both type 1 and type 2 diabetic patients, and a significant weight decrease in type 2 diabetic patients. While the EVADIAC registry shows the reduced occurrence of pump-pocket complications thanks to preventive measures and a lower incidence of catheter obstructions following improvements of catheter design, underdelivery due to insulin aggregation in pumps remains a recurrent although reversible issue. Determinants of increased anti-insulin antibody production in some patients remain elusive but impact on blood glucose control is limited in most cases. Conclusion From analyzed data, the EVADIAC group states that implantable pumps can be safely indicated and provide metabolic improvements in type 1 diabetic patients who remain far from targeted HbA 1c below 7% and/or experience large fluctuations of blood glucose including recurrent severe hypoglycaemia, in spite of intensive follow-up and education when treated by subcutaneous insulin.