The 12 month impact of continuous insulin infusion therapy on glycaemic control in adults with type 1 diabetes, at the Townsville hospital, Queensland - A retrospective study

Abstract

Aims: The purpose of this study was to assess the impact of continuous subcutaneous insulin infusion therapy (CSII) on glycosylated haemoglobin level (HbA1c), total daily dose of insulin (TDD), weight, episodes of diabetic ketoacidosis (DKA), severe hypoglycaemia, hospital admissions due to any other causes at 12 months of CSII therapy and to identify the predictive factors for good response to treatment, in patients attending the Townsville hospital diabetes centre. Methodology: This is a retrospective quality assurance single centre study. A total of 105 type 1 diabetes patients on continuous subcutaneous insulin infusion (CSII) were identified from 1st January 2001 to 31st December 2014 of whom; only 52 patients had sufficient data to be included in the study. The HbA1c, total daily dose of insulin and weight were collected 4 months before, after and at 12 months of CSII therapy. Patients demographic details, variables related to disease, treatment and follow up were also recorded. Results: Among the 52 patients analysed, 34.6% were males. The base line median HbA1c for females and males were 8.5% and 8.6% respectively. A significant reduction in baseline median HbA1c (8.6%) was noted both at 4 months {0.6%, (p=0.035)} and 12 months {0.7% (p=0.001)} of continuous subcutaneous insulin infusion therapy. The statistically significant reduction in HbA1c at 4 months was maintained at 12 months (p=0.025). At 12 months of CSII therapy a median HbA1c level of 7.7% was noted in those more than thirty years and 8.6% in less than 30 years of age. The median HbA1c was 7.8% in those who had diabetes for more than 10 years and 8% in less than 10 years. There was no difference in the median HbA1c in females (7.8%) and males (7.9%) at 12months of CSII therapy. At 4 months, the greatest reduction in HbA1c (1.1%) was observed in those who had a base line HbA1c of > 10%. A significant reduction in baseline median total daily dose (TDD) of insulin (57 units) noted both at 4 months (29.9 units (p<0.001) and 12 months (25u (p<0.001). There was no significant variation noted in the weight over 12 months. Conclusions: This study adds to the existing literature that continuous subcutaneous insulin infusion therapy significantly improves glycaemic control, reduced the total daily dose of insulin and had no effect on weight over 12 months. In our study age < 30 years and HbA1c of > 10% prior to commencement of therapy are predictors of poor glycaemic outcome at 12 months. Duration of diabetes and gender did not influence the glycaemic outcomes at 12 months.

Keywords

• 12 month, continuous subcutaneous insulin infusion, type 1 diabetes, glycaemic , predictive factors