Do GLP-1 Medications Put Your Eyes at Risk?

Credit: Adobe Stock/Syda Productions

People with diabetes who take glucagon-like peptide-1 (GLP-1) receptor agonists (such as Ozempic and Wegovy) may have more than twice the risk of developing a serious eye condition called neovascular age-related macular degeneration (nAMD) — a leading cause of vision loss in older adults — according to a large-scale study published in JAMA Ophthalmology.

nAMD is an advanced form of age-related macular degeneration, where abnormal blood vessels grow under the retina and damage central vision. It’s a serious condition that can lead to permanent vision loss if not treated promptly — accounting for up to 90% of vision loss among those with AMD.

“GLP-1 receptor agonists are extensively used in treating diabetes and obesity, yet little is known about the long-term ocular effects of systemic prolonged exposure,” wrote lead investigator Reut Shor, M.D., a researcher in the department of Ophthalmology and Vision Sciences at the University of Toronto.

The team followed 139,002 older adults with diabetes for up to three years in this population-based, retrospective cohort study conducted between January 2020 and November 2023 using administrative health and demographic data. Of these, approximately 46,000 were taking GLP-1 medications and 93,000 were not. Eligible patients were aged 66 years or older, were diagnosed with diabetes and had a minimum follow-up period of one year post diagnosis.

Among the group, the average age was 66.2 years and a little less than half were women. The mean follow-up times were 2.4 years in exposed patients and 2.5 years in unexposed patients. Of those receiving GLP-1s, nearly all (97.5%) were receiving semaglutide.

Results showed that those who were taking GLP-1 medications for at least six months had over twice the risk of developing nAMD compared with those not on the medications. This risk was the highest — more than three times as high — among patients with the longest exposure to GLP-1s.

While the overall number of affected patients was small (0.2% versus 0.1%), the difference was statistically significant.

“The pertinence of our findings is underscored by the dramatic increase in GLP-1 RA use, both in patients with diabetes and those with obesity without diabetes,” investigators wrote.

In another recent study, researchers found that people taking semaglutide had a higher risk of developing a serious eye condition called nonarteritic anterior ischemic optic neuropathy, which can cause sudden vision loss. One possible reason, investigators explained, is that these medications may affect blood flow or oxygen levels in the eye, which could also play a role in conditions such as nAMD.

In addition to GLP-1 use, older patients and those with a history of cerebrovascular accident also had a significantly higher risk of developing nAMD.

The team noted there are some important limitations to keep in mind. They didn’t separate results by specific brands or doses of GLP-1 drugs, and they couldn’t factor in how often or in what way the medications were taken. Some important health and lifestyle details — such as smoking or sun exposure — were not available, which means other factors could have influenced the results. Therefore, the investigators noted that more research is needed to fully understand why this link exists and whether certain patients are at higher risk than others.

“These findings expand upon the growing body of literature raising concerns regarding the potential ocular safety of systemic GLP-1 RA use in patients with diabetes,” investigators concluded. “However, it is also important to note that these findings demonstrate associations rather than cause and effect.”