Long-term improvement of metabolic control without increased risk of hypoglycaemia by intensive insulin regimens in type 1 diabetes patients treated in a regular clinical setting

Aim: To evaluate if intensive insulin regimen with multiple daily injections (MDI) is successful for treating type 1 diabetes patients over a long period of time in a regular clinical setting. Method: This is a prospective, observational seven-year study. Fifty-nine (35 male) type 1 diabetic patients with bad metabolic control (HbA(1c) >= 9%), aged 31.9 years, range 18-47 were included in the present study. All of them had had at least 5 years of diabetes duration after diagnosis and showed negative responses of serum C-peptide to a standard breakfast. The main control variables are: Metabolic control measured by serum HbA(1c) values (values < 6.2% was the treatment objective) and the frequency of hypoglycaemic episodes (episodes/patient-month). Results: Significant decreases in mean +/- SD HbA(1c) values in this group of patients were observed from the first year of follow-up, with the mean values being: 7.5 +/- 1.5%, 7.2 +/- 1.8%, 7.6 +/- 1.6%, 7.1 +/- 1.7%, 7 +/- 1.4, 6.6 +/- 1.6% and 6.8 +/- 1.4% for the first, second, third, fourth, fifth, sixth and seventh years of follow-up respectively. Sixteen %, 27.5%, 15.7%, 33.3 %, 28.6 %, 42% and 33 % of the patients reached the treatment objective (HbA(1c) values < 6.2%) for each year of follow-up. Throughout the study period the rate of severe hypoglycaernia (episodes/patient-year) was 0.32 +/- 0.2 which was not significantly different compared with the value of 0.28 +/- 0.1 observed the year before the study began. Similarly frequencies of mild/moderate hypoglycaemia episodes (episodes/patient-month) varies between 16.5 +/- 4 and 21.7 +/- 5, which are not significantly different from the value of 17.7 +/- 6 observed the year before the study began. Conclusion: Long-term improvement in metabolic control was observed in this group of type 1 diabetes patients with previous bad control, during treatment in a regular clinical setting. A considerable percentage of type I diabetic patients with MDI reached the treatment objective in every year of follow-up. Furthermore improvement in metabolic control is not associated with significantly increased frequency of hypoglycaernia episodes.