Associations between insulin pump self-management and HbA1c in type 1 diabetes.

Abstract

Insulin pump self-management is important for glycaemic outcomes. We aimed to investigate associations between self-management factors and HbA1c. Adult insulin pump users with type 1 diabetes (n= 770) completed an online questionnaire. The latest HbA1c and demographics were extracted from national registries. Associations between HbA1c and self-management (use of advanced features, timing of infusion set change, timing of meal bolus, data-upload and pump settings adjustments) were investigated using backward selected linear regression models. Of the 699 responders eligible for this study, 60% were women; the median age and diabetes duration were 49 and 25 years, respectively. Significant associations with HbA1c were found for changing infusion set every 0-4 days relative to 5-10 days (-5 mmol/mol (-0.4%), p= 0.003), and for never/rarely missing a bolus (-6 mmol/mol (-0.5%), p< 0.001) relative to often missing a bolus. Timing insulin 10-15 min before meal relative to after meal start was also associated with lower HbA1c (-3 mmol/mol (-0.3%), p= 0.023). Self-adjusting pump settings showed the strongest association with lower HbA1c (-6 mmol/mol (-0.6%), p< 0.001) relative to health care professionals doing all adjustments. Self-adjusting insulin pump settings, optimal timing and few omissions of meal boluses, and timely change of infusion set are associated with lower HbA1c.