The aim of the study was to determine the safety of three intensive insulin therapy methods: multiple daily insulin injections (MDI), continuous subcutaneous insulin infusion (CSII) and continuous intravenous insulin infusion (IVII) used in poorly controlled type 2 diabetic patients in hospital condition. The safety of these intensive insulin therapy methods was measured by the assessment of number and duration of symptomatic and symptomfree hypoglycaemic events with use of Continuous Glucose Monitoring System (CGMS, Medtronic MiniMed).
The study comprised 90 type 2 diabetic patients treated with conventional insulin therapy based on a twice daily injections with mean glucose profile values > 14 mmol/l. The patients were randomized into three groups according to the method of insulin treatment. The first group was treated with MDI, the second group with CSII and the third with IVII. The glucose monitoring with the use of CGMS lasted 48 hours and was conducted on the second and on the third day of intensive insulin therapy. Glucose level below 3.5 mmol/l were recognized as hypoglycaemic episode. Intensive insulin treatment was continued until "near normoglycaemia" (glucose levels 4.5-10.0 mmol/l) was achieved and then conventional insulin therapy was readministrated.
Mean number of symptomatic hypoglycaemic events detected with CGMS was two times higher for MDI than for IVII (p = 0.04) and for CSII (p = 0.04). Number of symptomfree hypoglycaemic events detected with CGMS was higher for MDI than for IVII and CSII, but the differences were insignificant (NS). Mean duration of one symptomfree hypoglycaemic event detected with CGMS was longer in MDI than in CSII (p = 0.02) and IVII (p = 0.03). It was not observed significant differences in mean duration of one symptomatic hypoglycaemic episode between studied groups (NS).
The results of study suggest that CSII and IVII treatment is associated with essentially lower number of symptomatic hypoglycaemic events and shorter mean duration of one symptomfree hypoglycaemic event than MDI.