From the Guidelines
Glucagon-like peptide-1 (GLP-1) receptor agonists, such as liraglutide, play a significant role in type 1 diabetes management as an adjunctive therapy to insulin, reducing post-meal glucose excursions, decreasing insulin requirements, and promoting weight loss, as evidenced by the most recent study in 2023 1.
Key Benefits of GLP-1 in Type 1 Diabetes
- Reducing glycemic variability
- Weight management
- Decreasing insulin requirements
- The primary benefit comes from these aspects rather than stimulating insulin production, as most patients have minimal beta cell function.
Administration and Monitoring
- Typical dosing of liraglutide starts at 0.6 mg daily for one week, then increases to 1.2 mg daily, with a maximum dose of 1.8 mg daily.
- When adding a GLP-1 agonist to a type 1 diabetes regimen, insulin doses often need to be reduced by 20-30% initially to prevent hypoglycemia, with further adjustments based on blood glucose monitoring 1.
Important Considerations
- Patients should be monitored for gastrointestinal side effects like nausea and vomiting, which typically improve over time.
- There is a potential risk of diabetic ketoacidosis, which can occur despite normal blood glucose levels, especially with the use of sodium–glucose co-transporter 2 (SGLT2) inhibitors, as noted in recent guidelines 1.
Evidence Summary
The most recent and highest quality study from 2023 1 supports the use of GLP-1 receptor agonists in type 1 diabetes, showing modest A1C reductions, decreases in weight, and reductions in insulin doses, making GLP-1 receptor agonists a valuable adjunctive therapy for selected patients with type 1 diabetes.
From the Research
GLP-1 Role in Type 1 Diabetes
- The role of Glucagon-Like Peptide-1 (GLP-1) analogues in the treatment of type 1 diabetes has been explored in several studies 2, 3, 4.
- These studies have shown that GLP-1 analogues, such as liraglutide and exenatide, can improve glycemic control, reduce insulin dose, and promote weight loss in patients with type 1 diabetes 2, 3, 4.
- The mechanisms of action of GLP-1 analogues include augmentation of hyperglycemia-induced insulin secretion, suppression of glucagon secretion, and deceleration of gastric emptying 5.
- The use of GLP-1 analogues in type 1 diabetes has been associated with a reduction in hemoglobin A1c (HbA1c) levels, total daily insulin dose, and body weight 2, 3, 4.
- However, the use of GLP-1 analogues in type 1 diabetes has also been associated with adverse effects, such as nausea and ketosis 4.
Efficacy of GLP-1 Analogues in Type 1 Diabetes
- A systematic review and meta-analysis of 24 studies found that liraglutide had a significant effect on HbA1c levels, body weight, and total daily insulin dose in patients with type 1 diabetes 4.
- The study found that liraglutide was associated with a reduction in HbA1c levels of -0.09%/mg, body weight of -2.2 kg/mg, and total daily insulin dose of -4.32 IU/mg 4.
- Exenatide was also found to have similar effect sizes, but the studies had a higher risk of bias and safety data were sparse 4.
Safety of GLP-1 Analogues in Type 1 Diabetes
- The use of GLP-1 analogues in type 1 diabetes has been associated with an increased risk of nausea and ketosis 4.
- However, the risk of severe or symptomatic hypoglycemia was not significantly elevated 4.
- The study found that the odds of nausea were higher with liraglutide (OR 6.5; 95% CI, 5.0-8.4) and ketosis (OR 1.8; 95% CI, 1.1-2.8) 4.