Common weight loss drugs linked to higher risk of vision loss

Credit: Unsplash+

A new study from Mass Eye and Ear has found that patients taking semaglutide, a medication for diabetes and weight loss, may have a higher risk of developing a serious eye condition called non-arteritic anterior ischemic optic neuropathy (NAION).

This condition can lead to blindness and affects the optic nerve. The findings were published on July 3 in JAMA Ophthalmology.

Led by Dr. Joseph Rizzo, director of the Neuro-Ophthalmology Service at Mass Eye and Ear and a professor at Harvard Medical School, the study discovered that people with diabetes who were prescribed semaglutide were more than four times more likely to be diagnosed with NAION compared to those not taking the drug.

For those who were overweight or obese, the risk was even higher, at more than seven times.

“The use of these drugs has exploded throughout industrialized countries and they have provided very significant benefits in many ways, but future discussions between a patient and their physician should include NAION as a potential risk,” said Dr. Rizzo.

He emphasized that while the increased risk is noteworthy, NAION itself is relatively rare, affecting up to 10 out of 100,000 people.

NAION is the second-leading cause of optic nerve blindness after glaucoma. It occurs when blood flow to the optic nerve head is reduced, causing permanent visual loss in one eye.

The visual loss from NAION is painless but can worsen over several days and typically does not improve. Currently, there are no effective treatments for NAION.

The study was prompted by a concerning trend noticed by Dr. Rizzo and his team in late summer 2023 when three patients were diagnosed with vision loss from NAION in one week. All three patients were taking semaglutide, prompting the team to investigate further.

Semaglutide was initially developed to treat type 2 diabetes and was marketed as Ozempic in 2017. It was later approved for weight management and branded as Wegovy in 2021. Its popularity has surged since then.

The researchers examined records from over 17,000 patients at Mass Eye and Ear over six years. They compared the rates of NAION diagnoses among patients prescribed semaglutide to those taking other diabetes or weight loss drugs.

The results showed a significant increase in NAION risk for those on semaglutide.

The study has some limitations. Mass Eye and Ear sees a higher number of patients with rare eye diseases, and the study population was predominantly white.

The total number of NAION cases in the study was relatively small, which means the statistics could change with larger studies. Additionally, the researchers could not confirm if the patients consistently took their medication or how this might have affected their risk.

The study does not prove that semaglutide causes NAION, and the researchers are unsure why this association exists. More extensive studies with more diverse populations are needed to further explore these findings.

“Our findings should be viewed as being significant but tentative,” Dr. Rizzo noted.

“This is information we did not have before and it should be included in discussions between patients and their doctors, especially if patients have other known optic nerve problems like glaucoma or if there is preexisting significant visual loss from other causes.”

In summary, while semaglutide has significant benefits for managing diabetes and aiding weight loss, patients and doctors should be aware of the potential risk of NAION and consider it in their treatment discussions. Further research is needed to better understand this risk and how to mitigate it.

If you care about eye health, please read studies about how vitamin B may help fight vision loss, and MIND diet may reduce risk of vision loss disease.

For more information about eye disease, please see recent studies about how to protect your eyes from glaucoma, and results showing this eye surgery may reduce dementia risk.

The research findings can be found in JAMA Ophthalmology.

Copyright © 2024 Knowridge Science Report. All rights reserved.