TUESDAY, March 17, 2026 (HealthDay News) -- Metformin use is associated with reduced odds of new-onset International Classification of Diseases (ICD) coding of neovascular age-related macular degeneration (nAMD), according to a study published online Jan. 30 in Ophthalmology Retina.
Jason F. Xiao, M.D., from the University of Chicago, and colleagues examined whether metformin use is associated with reduced odds of new-onset ICD coding of nAMD. A total of 22,205 cases with new-onset ICD coding of nAMD and 22,126 matched controls without AMD were identified between 2008 and 2017; a total of 6,664 cases and 5,513 controls were included as a subgroup of patients diagnosed with diabetes.
The researchers observed an association for any metformin use with reduced adjusted odds of new-onset nAMD (adjusted odds ratio, 0.84). Associations across cumulative-dose categories were heterogeneous in an exploratory dosing analysis, with the largest magnitude in the mid-dose range (between 271 and 600 g; adjusted odds ratio, 0.73). Dose-response findings were considered hypothesis-generating since adherence cannot be verified from claims. Among patients with diabetes, these associations persisted (adjusted odds ratios, 0.83, 0.72, and 0.85 for any metformin use, 271 to 600 g, and >1,080 g, respectively). Reduced odds of new-onset ICD nAMD were seen in association with any metformin use in patients with diabetes without retinopathy (adjusted odds ratio, 0.79); in patients with diabetes with retinopathy, this association was absent.
"Metformin's widespread availability and low-risk side-effect profile may make it a promising addition for preventing or managing nAMD," the authors write.
Two authors disclosed ties to the biopharmaceutical industry.