Hypothalamic-pituitary-adrenal response to different tests in type 1 diabetes mellitus

Abstract

Objective: To determine whether different tests of the adrenocorticotropic hormone (ACTH) reserve are influenced by diabetic state and metabolic control in newly diagnosed type 1 diabetic patients. Design and methods: We evaluated the ACTH reserve in 10 patients with uncomplicated type 1 diabetes during periods of poor and improved metabolic control and in 10 healthy subjects. The ACTHcortisol secretion was assessed by a diurnal profile, an intravenous corticotropinreleasing hormone (CRH) test and an insulin tolerance test (ITT ). Results: The diurnal profiles were similar in all groups. CRH resulted in a diminished ACTH response during poor compared with improved metabolic control (mean &#45 SD) (AUC 4950 &#45 4227 vs. 5847 &#45 3788 ng/L·min, p< 0.05). The response in the diabetic patients during improved metabolic control was of the same magnitude as in the control subjects (5934 &#45 1778 ng/L·min). ITT elicited a similar ACTH and cortisol response in the diabetic patients during poor and improved metabolic control as in the healthy control subjects. Conclusions: The ITT was uninfluenced by diabetic state and metabolic control and should therefore be considered the method of choice in evaluation of the ACTH reserve in patients with type 1 diabetes.

• Acth Corticotropin-RELEASING Hormone Cortisol Hypoglycaemia Insulin Pituitary-ADRENAL Function Tests