Longitudinal Islet Function And Insulin Requirement After Total Pancreatectomy With Islet Autotransplantation

Abstract

Presenter: William Lancaster MD | Medical University of South Carolina Background: Total pancreatectomy with islet autotransplantation is treatment for chronic pancreatitis. Though a significant proportion of patients do not require insulin postoperatively, evidence suggests that insulin independence declines over time. The objective of this study is to measure long term islet function and insulin independence after TPIAT. Methods: A retrospective analysis of a prospectively maintained database of patients undergoing TPIAT was conducted. Postoperative islet function was measured with serum C peptide levels. Postoperative insulin requirements and hemoglobin A1C values were tabulated. Results: A total of 190 patients were included. The mean islet transplant dose was 3545 IEq/kg. The mean serum C-peptide level was constant at 1.1 ng/mL at 6 months, 1 year, and 2 years postoperative. This decreased significantly to 0.5 ng/mL (p<0.05) at 3 years postoperative and remained at this level at 5 years postoperative. The rate of insulin independence was 32% and 30% at 1 and 2 years postoperative, respectively. Insulin independence declined at 3 years postoperative to 23% (p<0.05) and 20% at 5 years postoperative. The mean insulin requirement (units/day) was 26, 25, and 28 at 1, 3, and 5 years postoperative, respectively. Mean postoperative hemoglobin A1C values at 1, 3, and 5 years postoperative were 8.0, 8.2, and 7.8. Conclusion: Islet function declines over time after TPIAT with a corresponding decline in insulin independence rates at 3 years postoperative. In spite of this, glycemic control remains stable. Further study is needed to understand the decline in islet function over time and to develop preventive strategies.