The impact of postoperative exocrine index on non-alcoholic fatty liver disease following pancreaticoduodenectomy

Background: To study exocrine function of the remnant pancreas after pancreatoduodenectomy (PD), we propose the use of an exocrine index (PEI) that combines the volume of the remnant pancreas and the intraoperative amylase activity of the pancreatic juice. Here, we aimed to determine whether the PEI can predict non-alcoholic fatty liver disease (NAFLD) following PD. Methods: Fifty-seven patients for whom pancreatic juice amylase activity was measured during PD were enrolled. NAFLD was defined as a liver-to-spleen attenuation ratio of <0.9 on plain CT 1 year following surgery. We retrospectively evaluated clinical parameters, including the PEI, to identify predictors of NAFLD. Results: Fifty-four patients (95%) were regularly administered 1200 mg of pancreatic lipase. NAFLD was diagnosed in 13 participants (23%) 1 year following surgery. NAFLD was associated with pancreatic ductal adenocarcinoma (P =.006), soft pancreas (P =.001), small main pancreatic duct (P = 0008), low remnant pancreatic volume (P <.001), low intraoperative amylase activity in the pancreatic juice (P =.001), high pancreatic fibrosis (P =.032), and large body weight loss (P =.015). The PEI was significantly lower in the participants with NAFLD than in those without (P <.001). The participants were then classified into tertiles of PEI: <5 × 10⁶, 5-25 × 10⁶, and >25 × 10⁶. The prevalence of NAFLD in these groups was 53% (10/19), 11% (2/19), and 5% (1/19), respectively. In multivariable analyses, there was a significant association between NAFLD and the PEI (P value for trend =.042). Conclusion: The PEI, calculated using the remnant pancreatic volume and the intraoperative pancreatic juice amylase activity, predicts NAFLD development following PD.