Predictors of glycaemic control in patients with Type 1 diabetes commencing continuous subcutaneous insulin infusion therapy.

AIMS: To identify variables that predict glycaemic control in Type 1 diabetic patients switched to a continuous subcutaneous insulin infusion (CSII) regimen, in order to improve patient selection for this treatment.
METHODS: The notes of 421 Type 1 diabetic patients aged 2.6-39.8 years (median 19.4) who initiated CSII treatment in 1998-2007 and used it for > or = 1 year were reviewed. Details about their background and disease-related and treatment-related variables were recorded. At pump initiation, the mean age was 15.9 +/- 7.2 years, mean diabetes duration 6.4 +/- 5.8 years. Mean time of CSII use was 4.1 +/- 2.1 years. Good glycaemic control was defined by glycated haemoglobin (HbA(1c)) stratified by age (American Diabetes Association target levels). Improvement in glycaemic control was defined as a reduction of > or = 0.5% in HbA(1c) from baseline. The change in the rate of severe hypoglycaemic or diabetic ketoacidosis events was also determined.
RESULTS: There was a significant sustained decrease in HbA(1c) with CSII for an average of 6 years, without increased rates of hypoglycaemia. Achievement of target HbA(1c) was significantly associated with the following parameters at pump initiation: lower HbA(1c) (P < 0.001), younger age (< 12 years), shorter diabetes duration (P < 0.001) and more frequent daily self blood glucose monitoring (SBGM) (P < 0.01). Improved glycaemic control was associated with longer CSII use (P = 0.032) and higher HbA(1c) at CSII initiation (P < 0.001).
CONCLUSIONS: Switching patients to CSII resulted in sustained decrease in HbA(1c) and improved glycaemic control in patients with high HbA(1c). Young age, frequent SBGM and lower HbA(1c) at pump initiation were identified as predictors of achieving glycaemic targets with CSII.