A report published in Review of Optometry on November 5, 2018 announced research* showing that non-anemic patients with wet age-related macular degeneration (wAMD) who take oral iron supplements may be at risk of retinal/subretinal hemorrhage. Researchers have found that use of oral iron supplements was signiﬁcantly associated with retinal/subretinal hemorrhage at baseline in patients with wAMD. The amount of risk was dependent upon the dosage strength, particularly among those with high blood pressure (hypertension),.
The study looked at participants in the Comparison of AMD Treatments trial, a multicenter study of anti-VEGF treatments for wAMD. Among 1,165 participants, baseline retinal/subretinal hemorrhage was present in the study eye in 71% of 181 iron users and in 61% of 984 participants without iron use. The signiﬁcant association was strongest among those taking an iron dose of 18mg to 36mg. The association also remained significant among hypertensive participants without anemia.
The researchers believe that, in AMD patients, the iron supplements may interact with genetics to damage blood vessel cells in the retina. Further investigations are needed to delve further into this possibility. Meanwhile, patients taking iron supplements would wise to discuss these findings with their eye care specialists.
*Song, D, Ying GS, Dunaief JL, et al. Association between oral iron supplementation and retinal or subretinal hemorrhage in the comparison of age-related macular degeneration treatments trials. Retina. August 28, 2018. [Epub ahead of print]