A new review of real-world data on the use of the diabetes drug semaglutide has offered some reassuring news about its impact on vision loss.
While previous studies have found a link between a rapid improvement in glucose control and the risk of worsening diabetic retinopathy (DR), the new research shows that most people taking semaglutide do not develop DR or experience a worsening of existing DR.
The study has been presented at AAO 2023, the 127th annual meeting of the American Academy of Ophthalmology.
Lead researcher Dr Zeeshan Haq, from Retina Consultants of Minnesota, said further investigation is even more important now since the United States Food and Drug Administration recently greenlighted use of semaglutide as a weight loss aid. Ophthalmologists need more data to inform screening guidelines, monitoring schedules, and patient counselling, he said.
Diabetic retinopathy can cause vision loss and blindness in people who have diabetes because of high blood sugar levels damaging blood vessels in the back of the eye.
Semaglutide effectively decreases blood sugar, reduces appetite, and causes the stomach to empty more slowly, so that a person feels fuller faster.
But the effectiveness of semaglutide in causing a sudden drop in blood sugar, also known as glucose levels, is also a reason for concern with the previous studies finding an increased risk – albeit temporary – of worsening diabetic retinopathy.
Data Evaluation
To learn more, researchers used the IRIS Registry (Intelligent Research in Sight) to evaluate data from more than 48,000 adults with type 2 diabetes treated with injectable semaglutide. Subjects were between 51 and 75 years old and were treated between 2013 and 2021.
According to a news release issued by the AAO,1 the study found that after two years of treatment:
- Only 2.2% of eyes with no or background diabetic retinopathy experienced a worsening of diabetic retinopathy.
- In eyes with early-stage disease (mild or moderate nonproliferative diabetic retinopathy), 3.5% of eyes showed a worsening of diabetic retinopathy.
- Nearly 60% of eyes with advanced disease (severe nonproliferative or proliferative diabetic retinopathy) experienced an improvement in their diabetic retinopathy.
Dr Haq says that although results are promising for people with diabetes hoping to use semaglutide for weight loss and other health benefits, more research is needed.
“This study has significant limitations including its retrospective observational design, lack of a control group, and a lack of pre- and post-initiation of semaglutide comparisons,” Dr Haq said.
“In particular, the impact of semaglutide initiation on short- and long-term outcomes in potentially high-risk patients, such as those with severe non-proliferative or proliferative diabetic retinopathy, should be investigated further. Ultimately, diabetic patients who are considering semaglutide should consult with their primary and eye care providers regarding their individual situation.”
Researchers are working to learn more about the long-term effects of semaglutide on diabetic retinopathy in people with type 2 diabetes. A prospective clinical trial called FOCUS will evaluate the long-term effects of semaglutide in addition to diabetes medication on diabetic retinopathy. The study is expected to conclude in February 2027.
Reference
American Academy of Ophthalmology, Popular Weight Loss Drug Does Not Appear to Worsen Diabetic Eye Disease in Most Patients, New Study Suggests (media release), 3 Nov 2023. Available at: aao.org/newsroom/news-releases/detail/study-weight-loss-drug-doesnt-worsen-eye-disease [accessed 4 Dec 2023].
