Glucose metabolism after distal pancreatectomy - deterioration of beta cell function becomes noticeable at an early stage: A retrospective cohort study.
BACKGROUND: Distal pancreatectomy (DP) can worsen pancreatic endocrine function. Effects on glucose metabolism and underlying mechanisms after DP remains a topic of significant interest and not yet fully understood. This study aimed to examine the impact of DP on blood glucose homeostasis with a particular focus on metabolic outcomes and development of postoperative diabetes. METHODS: Considered were all patients who underwent DP between 01/2010 and 09/2021 and participated simultaneously in extended blood glucose monitoring with a 12 months follow-up. Blood samples were analyzed for markers of pancreatic endocrine function both fasting and after an oral glucose tolerance test preoperatively and 3 and 12 months after DP. RESULTS: Included patients (n = 69) were preoperatively categorized into three groups according to American Diabetes Association (ADA) criteria: 17 patients (24.6%) were normoglycemic (NG), 22 (31.9%) had prediabetes (impaired fasting glucose / impaired glucose tolerance - IFG/IGT) and 30 (43.5%) had diabetes mellitus (DM). In the NG subgroup, beta-cell function (HOMA2%B - updated homeostasis model assessment) significantly decreased from 117.4% (101.1-135%) to 66.9% (49.7-102.1%) at 12 months postoperatively (p < 0.05). Insulin sensitivity (HOMA2%S) significantly increased from 48.2% (33.4-66.9%) to 63.5% (49.8-86%) at 12 months postoperatively (p < 0.05). In the IFG/IGT subgroup, there was a non-significant trend of decreased HOMA2%B and increased HOMA2%S postoperatively. Postoperatively, 11.8% of NG patients and 60% of prediabetic patients developed DM. CONCLUSION: DP already leads to significant changes in glucose metabolism within a 12 month follow-up period. Patients with preoperative prediabetes are particularly at high risk of developing postoperative DM. Therefore, the indication for DP should be critically evaluated, especially in cases with a relative indication for surgery. If possible parenchymal sparing surgical options should be contemplated. TRIAL REGISTRATION: Not applicable.