Aims/hypothesis: This study was conducted to evaluate the long-term outcome of a structured outpatient diabetes teaching and treatment programme (DTTP) for intensified insulin therapy in patients with Type 1 diabetes, which aims to improve metabolic control without increasing the risk of severe hypoglycaemia.
Methods: All 123 diabetic outpatients (age 41+/-14 years; 64 women; BMI 23.5+/-3.1; diabetes duration 17+/-11 years; HbA1c 7.9+/-1.6%; 32 patients with a history of severe hypoglycaemia; 18 with overt nephropathy; 22 with proliferative retinopathy) who participated in the DTTP between June 1989 and June 1990 were invited for follow-up visits after 3, 6 and 12 years.
Results: Out of the 123 patients, 11 died during the follow-up period, two were lost for follow-up, and one was not willing to participate in re-evaluation after 12 years. Mean HbA1c levels decreased from 7.9+/-1.6% to 7.1+/-1.2% (p<0.01) after 3 years, and were 7.8+/-1.5% (NS) and 7.8+/-1.2% (NS) after 6 and 12 years respectively. Frequency of hypoglycaemia decreased from 0.49 episodes per patient per year to 0.14 after 3 years (p<0.01), 0.19 after 6 years (p<0.01) and 0.16 after 12 years (p<0.01). Of the participants, 41% were able to lower HbA1c levels without episodes of severe hypoglycaemia and to maintain this improvement at all follow-up visits over the 12-year period. At follow-up, intensified insulin therapy was carried out by 94% of the patients.
Conclusions/interpretation: A sustained reduction of the incidence of severe hypoglycaemia was observed in patients with Type 1 diabetes after participation in a structured outpatient DTTP over a 12-year period.