Analysis of nearly half a million diabetes patients reveals that those starting GLP-1 receptor agonists face an 85% increased risk of developing non-arteritic anterior ischemic optic neuropathy (NAION) compared to patients beginning SGLT2 inhibitors. The condition affects the optic nerve and can cause sudden, permanent vision loss. Over 6.7 months of follow-up, NAION occurred in an additional 0.29 cases per 1000 patient-years among GLP-1RA users.
This finding adds crucial context to the expanding use of semaglutide and related medications, now prescribed not only for diabetes but increasingly for weight management in broader populations. While NAION remains relatively rare, the elevated risk becomes clinically significant given millions of users worldwide. The study's strength lies in its massive scale and active-comparator design, which controls for diabetes severity and healthcare-seeking behavior better than previous research. However, the absolute risk increase remains small, and the observational design cannot definitively establish causation. Clinicians may need to weigh this vision risk against well-documented cardiovascular and metabolic benefits, particularly in patients with existing eye disease or other NAION risk factors.