The investigators believe that the emerging epidemiological evidence connecting topical use of corticosteroids to the development of type 2 diabetes and osteoporosis point to potentially massive, yet clinically unacknowledged problems associated with topical corticosteroid treatment. Using state-of-the-art methodology, the present study will delineate the impact of topical corticosteroid use on insulin sensitivity and bone turnover markers in patients with atopic dermatitis and, thus, provide important data that may have implications for millions of people using topical corticosteroids.

Inclusion criteria

• Age 18-75 years
• AD according to the Hanifin and Rajka Criteria24
• AD for at least 3 years
• BMI ≤ 30 kg/m2
• Haemoglobin A1c (HbA1c) ≤ 42 mmol/mol (6.0%)
• Normal haemoglobin (men: 8.3-10.5 mmol/L and women 7.3-9.5 mmol/L. A 5% deviation will be allowed if the patient besides this is healthy)
• Informed consent
• In general patients should not be diagnosed with diseases that may affect or be affected by the study/treatment (evaluated by a doctor) (such as untreated skin infections, acne vulgaris (beside face region), a skin barrier defect, such as Netherton's syndrome, lamellar ichthyosis, generalized erythroderma or cutaneous Graft Versus Host Disease, congenital or acquired immunodeficiencies or in patients on therapy that cause immunosuppression, and Protopic ointment should not be applied to lesions that are considered to be potentially malignant or pre-malignant. Further patients should not suffer from kidney or liver disease/insufficiency. See the SPC for Protopic and Betnovate.)

Exclusion criteria

• Diagnosed diabetes mellitus
• Other chronic inflammatory diseases (including but not limited to rheumatoid arthritis, inflammatory bowel disease etc) beside AD and non-treatment demanding rhinitis or asthma (treated within the last 4 weeks)
• Pregnancy (a urine test will be done at every visit and birth control is required, see below*)
• Breast feeding
• Treatment with drugs that might affect the glucose metabolism beside TCS within a month prior to the project
• Daily smoker, alcoholic, or drug abuser
• Hypersensitivity to Protopic or Betnovate