Adjusting background insulin therapy in type 2 diabetes when initiating a glucagon-like peptide 1 receptor agonist: A case series

Abstract

Introduction: Guidelines recommend preferential use of antihyperglycemic medications with proven cardiovascular benefit for the treatment of patients with type 2 diabetes with established atherosclerotic cardiovascular disease (ASCVD), high risk factors for ASCVD, kidney disease, or heart failure. However, current guidelines offer little to no practical recommendations for adding these therapies to a patient’s current regimen while avoiding hyperglycemia or hypoglycemia. Nevertheless, considering background therapy in a proactive effort to avoid undesirable glycemic excursions when initiating any new antidiabetic medication remains paramount. Case Series: A six-patient case series investigates adjustments to background therapies and glycemic outcomes surrounding the initiation and titration of long-acting glucagon-like peptide 1 receptor agonists (GLP-1 RAs) to shed light on practical methods to manage patient care during this tenuous phase. Overarching findings regarding background therapy adjustments to avoid hypoglycemia when initiating a GLP-1 RA include: (1) safe continuation of metformin regardless of baseline A1C or concurrent glycemic background therapy; (2) continuation of background therapy when the baseline A1C is above 9%; (3) consideration of a proactive 15–20% basal insulin dose reduction when the baseline A1C is below 7.5%; (4) proactive bolus insulin dose reduction by 25% or complete discontinuation at the time of GLP-1 RA initiation. Conclusion: No dose adjustments are necessary when A1C > 9%, and possibly >8%. When A1C is <7.5% and possibly <8%, discontinue or reduce bolus insulin by 25% and/or reduce basal insulin by 15–25%. Adjust background therapy using shared-decision making while considering fasting blood glucose, A1C, hypoglycemia risk, and chosen GLP-1 RA therapy.