From the Guidelines
GLP-1 receptor agonists, such as liraglutide, may be considered as adjuncts to insulin therapy in type 1 diabetes management, as they have shown modest improvements in glycemic control and weight loss, although they are not yet FDA-approved for this condition. The use of GLP-1 receptor agonists in type 1 diabetes has been studied in several clinical trials, with results showing reductions in A1C levels and body weight [ 1 ]. For example, a study published in 2023 found that the addition of liraglutide to insulin therapy in adults with type 1 diabetes resulted in a modest reduction in A1C levels (0.4%) and a decrease in body weight (5 kg) [ 1 ].
Key Considerations
- GLP-1 receptor agonists may be beneficial for overweight or obese type 1 diabetes patients struggling with insulin resistance
- Common side effects include nausea, vomiting, and diarrhea, which typically improve over time
- Patients should be monitored for potential diabetic ketoacidosis risk, as these medications may mask symptoms of hypoglycemia by reducing glucagon response
- Regular blood glucose monitoring remains essential, and insulin therapy must be continued, though doses may need adjustment to prevent hypoglycemia
Medication Options
- Liraglutide (1.8 mg daily) has been studied in clinical trials and shown to be effective in improving glycemic control and reducing body weight in type 1 diabetes patients [ 1 ]
- Other GLP-1 receptor agonists, such as semaglutide and dulaglutide, may also be considered, although their use in type 1 diabetes is not yet FDA-approved
- Typical starting doses are lower than those used for type 2 diabetes, such as 0.25mg weekly for semaglutide, gradually increasing based on response and tolerability [ 1 ]
Important Safety Information
- GLP-1 receptor agonists may increase the risk of diabetic ketoacidosis, particularly in patients with type 1 diabetes [ 1 ]
- Patients should be educated on the signs and symptoms of diabetic ketoacidosis and instructed to seek medical attention immediately if they occur [ 1 ]
From the Research
GLP-1 and GIP in Type 1 Diabetes
- GLP-1 is a hormone that stimulates insulin and inhibits glucagon secretion, and its receptor agonists have been approved for the treatment of type 2 diabetes 2.
- In type 1 diabetes, GLP-1 receptor agonists could have beneficial effects as an adjunctive therapy to insulin, improving glycemic control and body weight management 2, 3.
- Studies have shown that GLP-1 receptor agonists can reduce total daily insulin requirements, promote weight loss, and improve glycemic control in patients with type 1 diabetes 3.
- The role of GIP in type 1 diabetes is not well established, but it is known to be an incretin hormone that enhances insulin secretion in response to glucose 2.
- GLP-1 receptor agonists have been studied in patients with type 1 diabetes, with published evidence demonstrating weight loss, decreases in total daily insulin requirements, and modest improvements in glycemic control 3.
Mechanism of Action
- GLP-1 receptor agonists exert their effects through the interaction with GLP-1 receptors expressed in the pancreatic islets, lung, hypothalamus, stomach, heart, and kidney 2.
- The actions of GLP-1 include stimulating insulin secretion, inhibiting glucagon secretion, delaying gastric emptying, reducing appetite, and inducing satiety 2.
- GLP-1 receptor agonists have also been shown to increase beta-cell proliferation and differentiation and decrease the rate of beta-cell apoptosis in animal models 2.
Clinical Evidence
- Randomized, long-term, placebo-controlled clinical trials are warranted to fully establish the efficacy and safety of GLP-1 receptor agonists in type 1 diabetes 2, 3.
- Head-to-head clinical studies have demonstrated that all GLP-1 receptor agonist agents are effective therapeutic options at reducing A1C, but differences exist in terms of magnitude of effect on A1C and weight as well as frequency of adverse effects 4.
- Patients with type 1 diabetes who have detectable C-peptide and/or are overweight or cannot achieve glycemic goals without hypoglycemia may benefit the most from GLP-1 receptor agonist therapy 3.