Aims: To compare the effect of continuous subcutaneous insulin infusion (CSII) and multiple daily insulin injections (MDI) on albumin excretion rate (AER) in Type 1 diabetic patients.
Methods: In a 3-year multicentre retrospective observational study, 110 Type 1 diabetic patients treated with CSII were compared with 110 patients treated with MDI matched at baseline for age, sex, diabetes duration and HbA(1c). At entry, 90 patients in each group had normal AER and 20 persistent microalbuminuria. AER, estimated glomerular filtration rate (eGFR), HbA(1c,) lipids and blood pressure were assessed.
Results: HbA(1c) was lower in the CSII than in the MDI group (8.1 +/- 0.9 vs. 8.4 +/- 1.3%; P < 0.005 after 3 years). Blood pressure and eGFR were similar during the study. AER [median (95% confidence interval)], similar at baseline [6.0 microg/min (9, 21) in the CSII group vs. 4.4 (8, 16) in the MDI group, NS] was significantly lower in the patients treated with CSII both at year 2 and at year 3 of follow-up [4.7 microg/min (6, 12) vs. 6.4 (13, 29), P < 0.002]. This difference was observed even when normo- and microalbuminuric patients were analysed separately. Nine patients progressed to microalbuminuria in the MDI group and only one in the CSII group. Nine patients regressed to normoalbuminuria in the CSII group, whereas only two regressed to normoalbuminuria in the MDI group.
Conclusions: Despite a small benefit in terms of improved glycaemic control, CSII therapy may be useful in decreasing the progressive increase in AER in Type 1 diabetic patients.