Switching to Degludec is Associated with Reduced Hypoglycaemia, Irrespective of Definition Used or Patient Characteristics: Secondary Analysis of the ReFLeCT Prospective, Observational Study

Introduction: Hypoglycaemia is a common side effect of insulin therapy; low or high glycated haemoglobin (HbA1c) levels, history of hypoglycaemia or long diabetes duration are known modifiers of hypoglycaemia risk. In randomised clinical trials, lower rates of hypoglycaemia have been observed with the new-generation insulin analogue, long-acting insulin degludec, compared with other basal insulins. Methods: The ReFLeCT study was a prospective observational study over 12 months. Patient-reported diary data on hypoglycaemia were collected from patients with type 1 diabetes (T1D) or type 2 diabetes (T2D) who were switching from other basal insulins to insulin degludec (degludec) at their physician’s discretion in routine clinical care. Two secondary analyses were undertaken to investigate the change in number of hypoglycaemic events: a post hoc analysis using the updated American Diabetes Association (ADA) level 1, 2 and 3 hypoglycaemia definitions, and a pre-specified analysis using patient characteristics (baseline HbA1c, diabetes duration, and physician’s rationale for initiating degludec). Results: Switching to degludec was associated with significantly fewer hypoglycaemic events for all definitions in T1D, and level 1 and 2 in T2D (too few level 3 events for statistical comparison). Moreover, patient characteristics did not influence the observed reduction in hypoglycaemia in T1D and T2D. Conclusion: These results demonstrate that switching to degludec from other basal insulins was associated with reduced rates of hypoglycaemia, irrespective of the definition used or baseline patient characteristics. Trial Registration: NCT02392117.