People with diabetes who were taking GLP-1 drugs had a low but elevated risk of an age-related eye disease that can sometimes lead to blindness, a new observational study concludes, adding to a short list of concerns about eye health in people taking the powerful medications.
The risk was 0.2% in people taking GLP-1s and 0.1% in those who didn’t.
Aware of other eye problems in people taking GLP-1s, researchers looked for a relationship between the drugs and AMD.
There are GLP-1 receptors in the retina, the authors write, and GLP-1 drugs increase the levels of molecules that lead to harmful blood vessel formation.
Brian VanderBeek of the Scheie Eye Institute at the University of Pennsylvania said further research is also needed to pin down the association between the drug and higher rates of eye disease.
A recent observational study concludes that individuals with diabetes who were taking GLP-1 drugs had a low but elevated risk of an age-related eye disease that can occasionally result in blindness. This finding adds to a small list of concerns regarding eye health in those taking the potent medications.
After a year, more than twice as many individuals taking GLP-1 medications experienced neovascular age-related macular degeneration as those not taking the medication, according to the study, which was published Thursday in JAMA Ophthalmology. Those taking GLP-1s had a 0.2 percent risk, while those not taking them had a 0.1 percent risk. Participants were matched for socioeconomic status and a long list of conditions other than diabetes, and they were selected from the medical records of almost 140,000 patients in Canada.
AMD is a major cause of irreversible blindness in the elderly; the average age of study participants was 66. An advanced form of AMD called neovascular AMD (nAMD) is characterized by damage to the macula, the central region of the retina, and aberrant blood vessel growth. Frequent injections may be used to treat it and possibly stabilize or restore vision.
The same chronic heart failure and chronic kidney disease that make diabetic patients candidates for GLP-1s also affect people at risk for AMI. Researchers searched for a connection between GLP-1s and AMD because they were aware that patients taking the medication also experienced other eye issues.
At the University of Toronto, co-author Reut Shor told STAT, “It was remarkable to see such a clear signal in our study.”. “Although the advanced form of AMD has major effects on vision and quality of life, the absolute risk is still low.”. For vulnerable groups like older adults, who may already be at elevated baseline risk, a doubling of risk is therefore clinically meaningful. “.”.
GLP-1 medications, which are well-known for their ability to help people lose weight, were first developed to regulate blood sugar. Substance use disorders, Parkinson’s disease, hypertension, and cardiovascular disease have all been shown to be susceptible to their effects.
However, more eye issues, such as aberrant blood vessel growth, have been reported as their use has increased. When more people use a medication, uncommon side effects are common.
Two studies that included individuals with diabetes, cardiovascular risk, and a history of GLP-1 use for 20 or 24 months reported cases of this retinopathy. It was also discovered that individuals taking GLP-1s had an increased risk of nonarteritic anterior ischemic optic neuropathy (NAION), which occurs when the blood flow to the optic nerve is blocked.
Semaglutide, the active ingredient in Ozempic and Wegovy, has a very rare side effect that the European Medicines Agency’s safety committee called NAION on Friday. According to NAION, it may affect up to 1 in 10,000 people. The statement references research that indicates the risk of this eye ailment is twice as high for individuals with type 2 diabetes who take semaglutide as for those who do not.
Researchers hypothesize that if there is a common cause, it may be the abnormal growth of blood vessels in the retina caused by dropped blood glucose levels triggered by GLP-1s. Although the authors stress that the new study cannot prove that or even establish a cause-and-effect relationship, its findings raise concerns regarding the safety and eye health of diabetic patients receiving treatment.
Due to high blood sugar, diabetes itself has long been known to cause retinal degeneration, a condition that medications like the standard metformin have been able to manage. However, the problem with GLP-1s might not just be related to blood sugar.
The authors state that the retina contains GLP-1 receptors and that GLP-1 medications raise the concentrations of chemicals that cause destructive blood vessel formation.
The new study makes one wonder if the increased risk of nAMD is due to direct or indirect effects. To further elucidate causality, Shor stated that the research’s next steps should ideally involve large, prospective clinical studies in a variety of populations in addition to studies in human tissue and animal models to identify the mechanism. Research on GLP-1 users who do not have diabetes and are trying to lose weight would also be crucial.
These findings, according to Shor, should not raise alarms or lead to sudden changes in prescriptions just yet, but they do call for increased awareness and suitable monitoring.
Patients should therefore report any new visual symptoms—such as distorted or blurred vision, wavy straight lines, or new blind spots—as soon as they occur. According to Shor, these symptoms should prompt a prompt referral to an ophthalmologist for assessment as they may be early indicators of AMD.
Future studies may provide an answer to the open question of whether stopping the medication at that time would reduce the risk for AMD.
To determine whether the medication is linked to increased rates of eye disease, more research is also required, according to Brian VanderBeek of the University of Pennsylvania’s Scheie Eye Institute. He notes in a companion editorial that follow-up research on diabetic retinal disease and neuropathy in GLP-1 users revealed the risks were less than first believed. The new paper, however, raises some questions. According to him, if its conclusions are confirmed, up to 1 in 1,000 GLP-1 users may experience nAMD.
According to VenderBeek, “GLP-1 RAs have had a tremendous role in the care of patients with diabetes and now those who need additional help with weight management.”. Prescription doctors should be aware of the actual and severe ocular adverse events that can happen, even though they are not greater than the benefits these drugs provide. “.”.
