A recent real-world study tracked vision outcomes before and after patients began tirzepatide treatment.
Tirzepatide, the popular diabetes drug sold as Mounjaro and Zepbound, more than doubles the risk of developing a severe, sight-threatening eye condition in patients who already have eye damage, according to a large study published recently in Diabetologia.
The research found that 1.1 percent of tirzepatide users developed proliferative diabetic retinopathy (PDR)—a serious form of diabetic eye disease that can cause blindness—compared to just 0.5 percent of patients not taking the drug.
Most cases occurred in patients who already had mild retinal damage from diabetes.
Data From Nearly 7,000 Patients
Researchers analyzed electronic medical records from more than 6,800 adults with Type 2 diabetes at Imperial College London Diabetes Centre. The study compared 3,435 patients who took tirzepatide for at least six months with an equal number of matched patients who did not use the medication.
The research focused on patients who had eye screenings both before and after tirzepatide became available at the clinic in October 2022. Patients were carefully matched based on sex, duration of diabetes, baseline blood sugar control, retinal health status, and other medications.
In the general diabetic population, the prevalence of PDR is approximately 2.3 percent to 7.5 percent.
Researchers found tirzepatide use was associated with a little more than double the odds—115 percent—of developing PDR compared to those not on the medication. This translates to an incidence rate of about seven cases per 1,000 person-years among tirzepatide patients.
In PDR, abnormal new blood vessels (neovascularization) grow on the retina—and potentially the optic disc—leading to vision loss if not treated.
This condition is the most severe stage of diabetic retinopathy, a complication of diabetes.
Outcomes without treatment can include vitreous hemorrhage, retinal detachment, and neovascular glaucoma, which can cause blindness. Treatment options such as laser photocoagulation, injections, and surgery may help prevent or reduce vision loss.
