The Modulation of Euglycemic Endocrine and Exocrine Pancreatic Secretions in Iron Deficiency.

Objectives: The contribution of pancreatic secretions in iron metabolism has been elucidated, but the clinical outcomes of iron deficiency on pancreatic function are debatable. This study aimed to investigate the modulation of euglycemic endocrine and exocrine pancreatic excretions in response to variations in iron availability. Subjects and Methods: Serum levels of insulin, glucagon, insulin-to-glucagon ratio (IGR), and amylase were determined in 170 adult subjects with variable levels of serum iron. Results: Control (n = 46) and iron-deficient (n = 124) subjects had significant differences (p < 0.001) in their average levels of insulin (68.7 ± 0.5 vs. 100.0 ± 2.0 pmol/dL), glucagon (17.9 ± 0.6 vs. 10.8 ± 0.8 pmol/dL), IGR (4.0 ± 0.1 vs. 19.5 ± 2.1), and amylase (29.7 ± 0.9 vs. 17.5 ± 0.2). The upregulation of serum insulin levels increases proportionally and gradually to the extent of iron deficiency as compared to an abrupt downregulation of serum levels of glucagon and amylase. A significant association was observed between serum iron and IGR (r = −0.645, p < 0.001) and amylase levels (r = 0.653, p < 0.001). The receiver operating characteristic curve analysis defines an excellent predictivity of the reduced serum iron level to discriminate subjects with upregulated IGR and amylase levels with area under curves of 0.938 and 0.905, respectively. Conclusion: Iron deficiency is associated with an adaptive modulation of euglycemic endocrine and exocrine secretions that is consistent with a status of insulin resistance. Highlights of the Study: Iron deficiency (ID) exacerbates serum insulin levels proportional to the extent of deficiency. ID decreases the serum levels of glucagon and amylase with abrupt downregulation patterns. ID provides excellent predictivity for dysregulation in serum levels of insulin, glucagon, and amylase. Dysregulation of insulin-to-glucagon ratio and amylase levels in ID is consistent with insulin resistance status. [ABSTRACT FROM AUTHOR]