Mounjaro and Zepbound: New Hope for Preventing Vision Loss in Diabetes
A widely prescribed class of medications for type 2 diabetes, including Mounjaro and Zepbound (both containing tirzepatide), may also help reduce the risk of developing diabetic retinopathy, a leading cause of preventable blindness. Recent research suggests these medications could lessen the likelihood of worsening retinopathy or needing more intensive treatments.
Understanding Diabetic Retinopathy
Diabetic retinopathy is a diabetes complication that occurs when high blood sugar levels damage the blood vessels in the retina, the light-sensitive tissue at the back of the eye. It can lead to vision loss and blindness. Diabetes also increases the risk of other eye diseases, such as cataracts and glaucoma.
How Tirzepatide May Help
Tirzepatide is a dual GLP-1 (Glucagon-like Peptide-1) and GIP (Glucose-dependent Insulinotropic Polypeptide) receptor agonist. Unlike some earlier weight loss medications, studies indicate tirzepatide may not worsen diabetic retinopathy and could potentially offer protective benefits.
Researchers analyzed electronic health records from over 174,000 people with type 2 diabetes across 70 health systems in the United States. The study compared individuals starting tirzepatide with those pursuing lifestyle interventions like diet and exercise. After one year, those taking tirzepatide had a lower risk of worsening diabetic retinopathy or related complications.
For example, incident mild non-proliferative diabetic retinopathy occurred in 0.49% of tirzepatide patients compared with 1.2% of the lifestyle intervention group.
The Role of GLP-1 and Blood Sugar Control
Both tirzepatide and semaglutide medications work by mimicking the body’s natural GLP-1 hormone, suppressing appetite and helping to manage blood sugar levels. Experts believe that improved blood sugar control is a key factor in protecting against diabetic retinopathy.
Although some earlier research suggested semaglutide could temporarily worsen retinopathy, studies have shown no long-term association between semaglutide and increased progression of the disease over a three-year period.
Important Considerations
Researchers caution that the findings are preliminary and observational, meaning they display an association, not proof of cause and effect. Further long-term studies are needed to confirm these results.
According to the American Diabetes Association (ADA), diabetic retinopathy is the most common cause of preventable blindness in the United States.
Prevention and Monitoring
People at risk for diabetic retinopathy should maintain a healthy diet, quit smoking, and engage in regular moderate exercise. Everyone with diabetes should have a dilated eye exam annually, and anyone experiencing sudden vision changes should observe an ophthalmologist promptly.
Mounjaro vs. Zepbound: What’s the Difference?
Mounjaro and Zepbound both contain the same active ingredient, tirzepatide, but are approved for different uses. Mounjaro is approved for use alongside diet and exercise to improve blood sugar control in adults with type 2 diabetes, while Zepbound is approved for chronic weight management in adults with obesity or obesity-related conditions.