Adrenalectomy Versus Follow-up in Patients With Subclinical Cushings Syndrome (AUSC)

• Normalization of diabetes mellitus [ Time Frame: At two years after intervention ]
  Normalization of diabetes mellitus according to the criteria of the WHO and assessed by oral glucose tolerance test
• Decreased body mass index (BMI) to < 30 [ Time Frame: At two years post intervention ]
  Standard assessment of BMI
• Bone density [ Time Frame: At two years post intervention ]
  Bone density assessed with dual energy x-ray absorptiometry (DEXA) at the lumbar spine and hip
• Blood lipids [ Time Frame: At two years post intervention ]
  Triglyceride and cholesterol changes of whole serum and of the lipoprotein classes; low-density-lipoprotein (LDL), very-low-density-lipoprotein (VLDL) and high-density-lipoprotein (HDL)
• Cardiac function [ Time Frame: At two years post intervention ]
  Cardiac function assessed by echocardiography; left ventricular ejection fraction (EF), left ventricular end-diastolic diameter (LVDD), left ventricular mass index (LVMI), ratio between mitral peak velocity flow of the early filling wave and the atrial wave (E/A ratio)
• Cognitive function [ Time Frame: At two years after intervention ]
  Mini Mental State Examination (MMSE) for cognitive function
• Quality of Life [ Time Frame: At two years after intervention ]
  Quality of Life assessed by the generic instrument short form 36 (SF-36).
• Atherosclerosis [ Time Frame: At one and two years after intervention ]

  Carotid ultrasound/duplex scans with evaluation of intimal thickness and plaques.

  Blood pressure measurement for ankle index

Incidental findings of adrenal tumours,"incidentalomas", occur in 1-5 % in the general population and 10-25 % of these patients will exhibit biochemical mild hypercortisolism. Although the patients do not have clinical signs of classical Cushing's syndrome, they have an increased risk for hypertension, dyslipidemia, diabetes mellitus, osteoporosis and obesity.

The hypothesis of the study is, that surgery of the adrenal adenoma responsible for the increased secretion of cortisol, will in part cure or ameliorate the metabolic syndrome.

• No Intervention: Follow-up
  Patients who are diagnosed with biochemically mild hypercortisolism (so-called subclinical Cushing´s syndrome), who are followed only.
• Experimental: Surgery
  Patients diagnosed with adrenal tumour and with biochemically mild hypercortisolism (so-called subclinical Cushing´s syndrome), operated with adrenalectomy
  Intervention: Procedure: Adrenalectomy

Inclusion Criteria:

• Adrenal tumour with biochemical mild hypercortisolism defined as pathological dexamethasone suppression test (cortisol > 50 nmol/L at 8.00 am after 1 mg dexamethasone at 10 pm, plus one of the following criteria

  • Low or suppressed adrenocorticotropic hormone (ACTH)
  • Low or suppressed dehydroepiandrosterone (DHEA)
  • No or pathological circadian rhythm of cortisol

Exclusion Criteria:

• Increased levels of 24 hours urinary excretion of cortisol
• Pregnancy or lactation
• Inability to understand information or to comply with scheduled follow-up
• Mild hypercortisolism with bilateral adrenal tumours, without a gradient (lateralization on venous sampling)