Impact of Metformin Use on Age-Related Macular Degeneration Among Patients Without Diabetes
Metformin use among individuals without diabetes was associated with a reduced risk of developing age-related macular degeneration (AMD), according to the results of a recent case-control study.
The researchers utilized data from a nationwide insurance claims database from 2006 to 2017 to identify patients with AMD and match them 1:1 to control patients without AMD. All participants were aged 55 years or older and were matched by year, age, anemia, hypertension, region, and Charlson Comorbidity Index score.
Only cases and matched controls who did not have a diabetes diagnosis were included. Additionally, all participants’ exposure to metformin in the 2 years prior to the study index date was categorized into quartiles based on cumulative dose. The index date was defined here as the date of diagnosis for those with AMD and the date of eye examination for the control group.
The results indicated that 1.0% (n = 2268) of those with AMD and 1.3% (n = 3087) of controls had utilized metformin within 2 years before their index visit. This use was associated with reduced odds of AMD development (adjusted odds ratio [AOR] = 0.83; 95% CI, 0.74 to 0.87), particularly for patients who had dosing of 1 to 270, 271 to 6000, and 601 to 1080 g/2 y.
Further, reduced odds of dry AMD development were observed with any metformin use (AOR = 0.85; 95% CI, 0.79 to 0.92), and particularly among those in the 1 to 270 and 271 to 600 g/2 y quartiles. The adjusted odds ratios for any AMD and dry AMD development did not differ among the dosing quartiles.
“Findings of this study suggest that metformin may be useful as a therapeutic tool for protection against AMD development in patients without diabetes,” the researchers concluded.
“These findings provide further impetus to study metformin’s usefulness in protecting against AMD in prospective clinical trials.”
Reference:
Aggarwal S, Moir J, Hyman MJ. Metformin use and age-related macular degeneration in patients without diabetes. JAMA Ophthalmol. 2024;142(1);53-57. doi:10.1001/jamaophthalmol.2023.5478