Metabolic effect of pancreatoduodenectomy: Resolution of diabetes mellitus after surgery

Abstract

It is considered natural that glucose tolerance worsens after pancreatectomy. However, diabetes mellitus (DM) resolves after metabolic bypass surgery and anatomic changes after PD resemble those after metabolic surgery. This study assessed the incidence of DM resolution after pancreatectomy and differences in metabolic parameters following pancreatoduodenectomy (PD) and distal pancreatectomy (DP). Between 2007 and 2013, 218 consecutive patients with pancreatic diseases underwent PD (n=112) or DP (n=106) at Seoul National University Hospital. Factors associated with changes in glucose homeostasis were evaluated by assaying serum glucose concentrations in prospectively collected samples. Of the 218 patients, 88 (40.4%) had preoperative DM, with 27 (30.7%) of the latter showing postoperative resolution of DM, a rate significantly higher in patients who had undergone PD than DP (40.4% vs. 12.9%, p=0.008). Fasting blood glucose (p=0.001), PP2 (p<0.001), and HOMA-IR (p=0.005) significantly decreased after PD but not after DP. Multivariate analysis revealed that PD was independently associated with DM resolution (odds ratio 7.790, p=0.003). PD was associated with a significantly higher DM resolution rate than DP among the 37 pancreatic cancer patients with preoperative DM (34.6% vs. 0%, p=0.036). DM resolution rates were similar in pancreatic cancer and other pancreatic diseases (p=0.419). More than 40% of patients with preoperative DM show resolution after PD. Decreased insulin resistance and suspected enhanced glucose stimulated insulin secretion decreasing PP2 seem to contribute improved glucose homeostasis after PD. BMI was unrelated to DM resolution, indicating that PD-associated physio-anatomical changes may help resolve DM independent of weight.