Endocrine Abstracts

Objective: One of the major problems related to the use of CSII, or intensive insulin regimens in general, is the calculation of accurate insulin boluses. Abolus calculator incorporated into the insulin pump, estimates the dose of insulin to be administered at the meal on the basis of the following parameters: current blood glucose, grams of carbohydrate in the meal, carbohydrate to-insulin ratio (CIR), insulin sensitivity factors (ISF), target blood glucose and quantity of insulin previously administered, hereby making calculation easier and more precise.

The aim of the present study was to assess the efficacy of a bolus calculator incorporated into the insulin pump on pre and postprandial glycaemic control of patients with type 1 diabetes on continuous s.c. insulin infusion, evaluating changes in insulin dose, number of boluses administered, acute complications, glycemic variability and HbA1c, and quality of life.

Material y methods: We enrolled 20 subjects (8 men/12 women) older than 18 years old (mean age: 36±12 years) with type 1 diabetes patients treated for more than 12 months (time on insulin pump therapy: 50±32 months) with continuous s.c. insulin infusion (Minimed 722, Medtronic). The patients received a infrared-linked glucometer (Contour Bayer) so that glycemic values were directly transmitted to the pump to be used by the bolus calculator, with possibility to download all the recorded data.

We calculate basal CIR and ISF for all the patients, who received all the information for the accurate use of the bolus calculator.

The following data were evaluated baseline and after 3 months using the bolus calculator: HbA1c, daily insulin dose(Basal and bolus), number of bolus/day, acute complications. Glycemiclability was evaluated using MAGE and S.D. from SMBG information, and quality of life (DQOL). A treatment satisfaction questionnaire was also evaluated.

Results: After 3 months using the bolus calculator we observed significant changes (P< 0.05) in weight (71.8±8 vs 72.9 kg)and methabolic control (HbA1C 7.7±1.1 vs 7.5±1%), we did not find differences in SMBG downloaded data (time in normo, hypo and hyperglucemia), S.D., MAGE, insulin daily dose, basal/bolus distribution, number of boluses/day, and DQOL.

Patients were satisfied with the bolus calculator, they find this option easy to use and accurate.

Conclusions: In a group of patients treated with continuous s.c. insulin infusion the addition of the use of a bolus calculator achieved an improvement in glycemic control with decrease of HbA1c levels, without changes in other studied parameters, with a high level of satisfaction of the patients.