Incidence of metformin use in patients with age-related macular degeneration versus normal controls: A population-based study in Olmsted County, Minnesota

Purpose The purpose of this study is to compare the use of metformin in patients with both exudative and non-exudative age-related macular degeneration (AMD) versus control populations. Design Retrospective review of three age- and sex-matched cohorts from 1/1/2004 to 12/31/2013: patients with exudative AMD, a cohort of dry AMD patients, and a cohort of patients without AMD. The primary endpoint was the incidence of metformin use in all of the cohorts. Results There were 1512 patients, with 504 in each of the three cohorts. There was no difference in the prevalence of diabetes between cohorts. Compared to patients with dry AMD, patients with no AMD had increased likelihood of metformin use (p = 0.0168, OR 1.66 (1.09-2.51). There was no difference in the likelihood of metformin use between exudative AMD patients and non-AMD controls. Conclusions There appears to be an increased incidence of metformin use in patients without AMD compared to patients with dry AMD. Metformin's current role in the treatment of anti-aging diseases makes it a plausible target for use in the treatment of AMD, particularly dry AMD.