Continuous Correction

The potential of currently available diabetes technologies could be further exploited. The investigators propose that sensor-augmented insulin pump therapy may be improved by continuous correction, i.e. continuous evaluation of the need for correction boluses. In practice, this is carried out by running the bolus calculator every 10 minutes. The glucose sensor will provide the bolus calculator with glucose input. Many times, the bolus calculator will come to the result that no insulin is needed. However, when the blood glucose is above the pre-set target value and a correction bolus is needed, an appropriate bolus is automatically delivered by the insulin pump. The investigators hypothesize that sensor-augmented continuous correction insulin pump therapy can reduce hyperglycemia without increasing the risk of hypoglycemia in patients with type 1 diabetes.

Type 1 diabetes, Continuous Glucose Monitoring, Insulin pump, Sensor-augmented pump, Continuous correction of high blood glucose

The insulin pump is set to automatically deliver the patient's usual insulin basal rate. The insulin pump bolus calculator is run every 10 minutes by the attending physician. Bolus calculations are based on glucose sensor values.

The primary outcome is difference in the percentage of time CGM values are in the target range 3.9-8.0 mmol/l in the time period 8:00-17:00 on CC-days and Control-days.

CGM accuracy will be evaluated with Hemocue glucose values as reference (mean absolute relative difference).

Inclusion Criteria: Age ≥ 18 years T1D ≥ 3 years CSII ≥ 1 year HbA1c ≤ 8.0% (64 mmol/mol) Exclusion Criteria: Pregnancy or nursing Hypoglycemia unawareness Gastroparesis Use of anti-diabetic medicine (other than insulin), corticosteroids or other drugs affecting glucose metabolism during or within 30 days prior to the study Other concomitant medical or psychological condition that according to the investigator's assessment makes the patient unsuitable for study participation