Pheochromocytoma With Adrenergic Biochemical Phenotype Shows Decreased GLP-1 Secretion and Impaired Glucose Tolerance

Abstract Context Impaired glucose homeostasis is a common finding in pheochromocytoma (PHEO), especially with adrenergic phenotype. The possible contribution of incretin dysfunction to dysglycemia in PHEO patients has not been studied. Objective To compare changes in pancreatic endocrine function and gut hormones’ production during a liquid meal test before and 1 year after adrenalectomy. Methods In a prospective study, we included 18 patients with PHEO (13 females) with adrenergic biochemical phenotype. A liquid meal test with predefined isocaloric enteral nutrition was performed to evaluate dynamic changes in pancreatic hormones and incretins. Results During the meal test, insulin levels were significantly lower before adrenalectomy only in the early phase of insulin secretion, but changes in area under the curve (AUC) did not reach statistical significance (AUC = 0.07). Plasma glucagon (AUC