Patients with adrenal insufficiency also exhibit an adrenomedullary dysfunction. Furthermore, patients who suffer from both, adrenal insufficiency and type I diabetes more frequently report hypoglycemia, particularly after strenuous activities. The study investigates the counter regulatory hormonal response to physical stress and the impact on cognitive function in subjects with and without Addison's disease, type I diabetes and healthy subjects.

As patients with adrenal insufficiency also exhibit an adrenomedullary dysfunction and patients who suffer from both, adrenal insufficiency and type I diabetes more frequently report hypoglycemia, particularly after strenuous activities this study investigates the counter-regulatory hormonal response to physical stress and the impact on cognitive function in subjects with and without Addison's disease, type I diabetes and healthy subjects. Patients will perform ergometer training with an individualized intensity and fulfill cognitive function testing (stroop test and fatigue inventories) before and after strenuous activity.

Inclusion Criteria:

• Diagnosis of Addison's disease and/or diabetes mellitus type I or healthy control with normal adrenal function and normal glucose regulation
• Age ≥ 18 years
• Ability to comply with the study protocol
• Capability to perform spiroergometry

Exclusion Criteria:

• Any contraindication for performing spiroergometry according to the guidelines of the German Cardiac Society:

  • acute myocardial infarction
  • instable angina pectoris
  • symptomatic arrhythmia
  • severe and symptomatic stenosis of the aortic valve
  • decompensated heart failure
  • acute pulmonary embolism
  • Acute myocarditis
  • Acute pericarditis
  • Acute aortic dissection
  • main coronary artery disease
  • valvulopathies
  • electrolyte disturbance
  • arterial hypertension (systolic blood pressure > 200 mm Hg, diastolic BP > 110 mm Hg)
  • Tachyarrhythmia or Bradyarrhythmia
  • Hypertrophic cardiomyopathy and other forms of obstructive heart disease
  • second or third degree atrioventricular block

• Fever

• Diabetes mellitus Type 2

• Diseases or medication influencing the endogenous levels of plasma catecholamines(e. g. pheochromocytoma, paraganglioma, antidepressants, levodopa)

• Glucocorticoid-pharmacotherapy

Four groups:

Patients with Addison's disease alone patients with diabetes mellitus type I alone patients with both, Addison's disease and Diabetes mellitus type I healthy controls