Degree of islet function preservation and continuous glucose monitoring in individuals undergoing total pancreatectomy with islet autotransplantation

Abstract Aims/hypothesis In individuals undergoing total pancreatectomy, an additional islet autotransplantation (total pancreatectomy with islet autotransplantation [TPIAT]) can be performed. We investigated the degree to which islet secretory function is preserved after TPIAT and assessed the relation to glycaemic control using continuous glucose monitoring. Methods Eligibility for TPIAT was assessed by a multidisciplinary team. The cohort consisted of all individuals undergoing TPIAT from 2014 to 2024. To assess islet secretory function, participants were subjected to a 2 h liquid meal stimulation test prior to TPIAT, at 3 months and annually post TPIAT. Glycaemic control was assessed using continuous glucose monitoring and HbA 1c . Results Twenty-six individuals were included, of whom 88.5% had chronic pancreatitis. At baseline, 57.7% had prediabetes (HbA 1c 39–47 mmol/mol [5.7–6.4%] or a fasting glucose 5.6–6.9 mmol/l) or diabetes, and 46.2% had undergone previous pancreatic surgery. Islet secretory function determined by C-peptide area under the curve (AUC C-peptide ) was 45% of baseline at 3 months post TPIAT. Preservation of islet secretory function was independent of preoperative glycaemic status and previous surgery. At 3 months, time in range was 75.2 ± 26.1%, and time in range was positively correlated with AUC C-peptide ( p <0.0001). After 3 months islet function did not significantly change, which was reflected in a stable BETA-2 score. Conclusions/interpretation Nearly half of islet secretory function is retained after TPIAT. These results can facilitate shared decisions on the potential benefits of islet autotransplantation after total pancreatectomy, even in individuals with (pre)diabetes and previous pancreatic surgery.