A significant shift in treatment patterns for type 1 diabetes has emerged, with GLP-1 receptor agonist medications increasingly being prescribed to patients despite limited safety and efficacy data for this specific population, according to a new study published in the journal Diabetes, Obesity and Metabolism.
Researchers from Johns Hopkins University reviewed medical records of more than 200,000 people with type 1 diabetes from 2008 to 2023, revealing an 800% increase in GLP-1 medication use among adults with severe obesity – from approximately 4% in 2008 to 33% by 2023.
Rising Obesity Rates Driving Off-Label Prescribing
The study documented a substantial increase in obesity rates among type 1 diabetes patients during the study period. For children aged 2 to 19 with type 1 diabetes, obesity rates climbed from 18% to 26%, while adults saw an increase from 30% to 38%.
This trend appears to be driving the growing use of GLP-1 medications like semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound) in this patient population, despite these drugs not being FDA-approved for type 1 diabetes.
"These findings highlight the urgent need for better data — including clinical trials — on the effectiveness and safety of GLP-1 receptor agonists in people with type 1 diabetes, to inform clear guidelines on their use in these patients," said Dr. Jung-Im Shin, an epidemiologist and associate professor at Johns Hopkins Bloomberg School of Public Health who led the research.
Safety Concerns and Hypoglycemia Risk
The family of GLP-1 receptor agonist medications was originally developed to treat type 2 diabetes, which occurs when the body's cells become resistant to insulin. Some have subsequently received approval for weight management, sleep apnea treatment, and cardiovascular risk reduction.
However, clinical trials for these medications specifically excluded people with type 1 diabetes, who depend on insulin because they cannot produce sufficient amounts naturally. Pharmaceutical companies were concerned that combining GLP-1 medications with insulin might increase the risk of dangerous hypoglycemic events.
The medication labels for drugs like Ozempic and Mounjaro explicitly state they are not intended for use in type 1 diabetes. Despite this, many physicians have begun prescribing these medications off-label for their type 1 patients, particularly those struggling with obesity.
"We really need the clinical trial data dedicated for this type 1 diabetes population and see whether this is effective and safe in this population," Dr. Shin emphasized.
Potential Benefits Versus Unknown Risks
Some type 1 diabetes patients report that GLP-1 drugs have been transformative, helping them gain better control of blood sugar fluctuations and achieve weight loss – something particularly challenging for insulin users, as insulin signals the body to store excess blood sugar as fat.
Dr. Viral Shah, an endocrinologist and director of diabetes clinical research at Indiana University School of Medicine who was not involved in the study, noted that many endocrinologists now recognize potential benefits of adding a second medication alongside insulin for certain type 1 diabetes patients.
"Most endocrinologists nowadays do understand that people with type 1 diabetes – not everyone, but some, would benefit," Shah said. GLP-1 drugs may help reduce insulin requirements and assist with weight management in those with obesity.
However, Shah cautions that careful dosing of both GLP-1 medications and insulin is critical due to hypoglycemia risks, and he advises against these drugs for type 1 patients who are not overweight, as retrospective studies indicate this group may experience more gastrointestinal side effects.
Clinical Trials Underway
Several studies are currently investigating GLP-1 medications in type 1 diabetes, including one led by Dr. Shah that will be presented at the American Diabetes Association's annual meeting in June. This randomized, double-blinded study included type 1 diabetes patients with obesity who use an artificial pancreas system, with half receiving weekly semaglutide injections and half receiving placebo over six months.
The Johns Hopkins researchers are also conducting a follow-up study specifically examining the risk of severe hypoglycemia among type 1 diabetes patients using GLP-1 drugs.
As the prevalence of obesity continues to rise in the type 1 diabetes population, the need for evidence-based guidance on the safety and efficacy of GLP-1 medications becomes increasingly urgent. Until more comprehensive clinical trial data becomes available, patients and healthcare providers must carefully weigh potential benefits against unknown risks when considering these medications for type 1 diabetes management.
