Two sides of the pancreas: Exocrine insufficiency is correlated with endocrine dysfunction in type 2 diabetes

Background: Recently, numerous studies validated frequent pancreatic exocrine dysfunction in patients with diabetes. However, the prevalence of pancreatic exocrine insufficiency (PEI) in diabetes mellitus (DM) varies widely among studies. This study aims to determine the prevalence of PEI in Chinese people with type 2 DM (T2DM) by measuring the fecal elastase-1 (FE-1) levels and further identify potential factors that influence pancreatic exocrine function in patients with T2DM. Methods: A total of 85 patients with T2DM without known exocrine pancreatic disorders or digestive system diseases were recruited. Fecal samples were submitted to measure FE-1 levels, and blood samples were collected to investigate pancreatic endocrine function and metabolic biomarkers in all participants. The multiple logistic regression analysis was established to evaluate the influencing factors of PEI in patients with T2DM. The potential predictors of PEI were examined using receiver operating characteristic (ROC) curves. Results: The prevalence of PEI measured by low FE-1 in T2DM was 18.8%. The Spearman correlation demonstrated that the FE-1 level was inversely correlated with DM duration (r = -0.360, P = 0.001) and glycated hemoglobin (HbA1c) level (r = -0.228, P = 0.036). A highly significant positive association was observed between FE-1 and fasting C-peptide (FCP) levels (r = 0.451, P < 0.001). Furthermore, the multiple logistic regression analysis showed that FCP was an independent influencing factor of PEI (OR = 0.204, P = 0.024, 95% CI: 0.051-0.813). The ROC analysis indicated that the FCP level had a predictive value for low FE-1 (AUC = 0.793, P < 0.001) with an optimal cutoff value of 1.20 ng/ml. Conclusion: Chinese patients with T2DM show high PEI prevalence. FCP may be a potential predictor of pathological exocrine function in T2DM. The exocrine and endocrine functions of patients with T2DM in clinical practice should be evaluated. Further studies are needed to clarify the internal association between exocrine and endocrine pancreases.