Effects of Insulin Detemir and NPH Insulin on Renal Handling of Sodium, Fluid Retention, and Weight in Type 2 Diabetic Patients

Type 2 diabetic patients experience weight gain when receiving insulin treatment. There has been reports that the weight gain is less or absent when patients are treated with Insulin Detemir. Patients with diabetes have increased total body sodium and increased extracellular volume. We hypothesize that part of the weight gain seen is due to increase in extracellular volume and that the lesser weight gain seen in patients treated with Detemir is due to an lesser increase in extracellular volume. We believe that the cause of this difference is the different pharmacokinetic properties of insulin Detemir. Insulin Detemir i protein bound and is therefore not excreted in the kidneys. This may cause less sodium reabsorption, than with other insulins, and therefore less increase in extracellular volume.

We test this hypothesis by examining urinary sodium excretion, extracellular volume by GFR measurements, Body composition by DEXA scan, body weight, and 24 hour blood pressure.In patients that are changed from Insulin Insulatard to Insulin Detemir and back.

Inclusion criteria

• Type 2 diabetes according to WHO 1999 criteria for at least 3 month
• Insulin treated for at least 1 month
• BMI 25-40
• Age 18-80
• Hb1Ac < 10%

Exclusion criteria

• Hypertension not well regulated
• Serum creatinine > 130 micromol/l
• Non-diabetic kidney disease
• Disease that may cause invalid hgbA1c measurement
• Substance abuse
• Recent use of Detemir
• Pregnancy or risk of becoming pregnant
• Any condition that may disturb protocol adherence (language barrier etc) urinary albumin > 30 mg/24hours ( before screening)
• Use of drugs that may influence blood glucose (except oral antidiabetics)
• Use of drugs that may influence sodium balance,i.e diuretics ( tiazides accepted)
• Clinical significant disease that may influence outcome ( cancer etc)