Safety assessment and potential risks of the glucagon stimulation test in the diagnosis of secondary adrenal insufficiency

Abstract

Background: Although it takes more time, the glucagon stimulation test (GST) is a reliable measure for assessing growth hormone (GH) and adrenocorticotropic hormone (ACTH) secretion. The GST is considered to be a safe test, however, it still has mild side effects and potential risks. Objective : The objective of this study was to analyze the side effects of the GST while testing adrenal insufficient patients. Methods: This was a prospective study in which GST was performed in eighty-one patients (44 men, 37 women, mean age: 35.83±19.62 years) with pituitary disorder. The GST consisted in an intramuscular injection of 1 mg of glucagon. Blood samples were collected at baseline, and 30, 60, 90, 120, 150, 180 and 210 min after glucagon injection for cortisol measurements. All patients were asked to report side-effects associated with this test. Results: The mean peak blood glucose level under GST was 9.01±2.03 mmol/L and the mean glycemic nadir was 4.34±1.75 mmol/L was found most frequently during the 30th minute (p <10-3). During the test, 35 subjects (43.2%) had side effects with a mean age of 42.89 ± 19.75 years. Frequent side effects included: nausea (29.62%), vomiting (27.16%), abdominal cramps (18.51%) and hunger (13.58%). All patients tolerated the test until the end. Adverse effects were significantly more prevalent in patients older than 50 years (p=0.012). Conclusions: The GST is a reliable alternative to assess hypothalamic pituitary adrenal axis but should be cautiously used especially in the elderly although its minor side effects.