Study: ​​Blue-blocking IOLs Not Advantageous Against Wet AMD

The theoretical basis for blocking blue light to reduce retinal toxicity and prevent AMD development has been established. This concept, combined with studies suggesting that cataract surgery may increase AMD risk, has driven the development and continuous refinement of blue-light filtering IOLs. However, clear evidence supporting their effectiveness in reducing AMD incidence is still lacking, and findings have been inconsistent across studies. Photo: National Eye Institute. Click image to enlarge. Since the natural aging lens absorbs blue light, its replacement with a clear intraocular lens (IOL) during cataract surgery has raised concerns that increased retinal exposure to blue light may make the retina and retinal pigment epithelium (RPE) more vulnerable, potentially elevating the risk of age-related macular degeneration (AMD) development. Evidence supporting this has been scant, however. As such, researchers in South Korea sought to determine whether blue-light filtering IOLs effectively reduce AMD incidence in daily environments. Their study, published in American Journal of Ophthalmology, assessed the risk of wet AMD in patients who underwent bilateral blue light-filtering IOL implantation within one year compared to that of those with clear IOLs. They found that blue light-filtering IOL implantation in cataract surgery does not reduce the risk of developing wet AMD in a South Korean population, regardless of a history of dry AMD.The nationwide, population-based cohort study used data from the Korean National Health Insurance Sharing Service database. A total of 21,741 individuals with blue-light filtering IOLs were compared to 56,357 individuals with clear IOLs. The mean follow-up duration was 7.0 years in the blue light-filtering IOL group and 6.7 years in the clear IOL group.The 10-year cumulative incidence of wet AMD was 1.8% in the blue-blocking IOL group and 1.7% in the clear IOL group. The incidence rates per 100,000 person-years were 162.8 and 153.9 in the blue light-filtering IOL group and clear IOL groups, respectively, with no significant difference using two statistical models: the adjusted Cox model (adjusted hazard ratio; aHR: 1.12) and the Fine-Gray model (aHR: 1.15). Subgroup analyses based on age, sex and history of dry AMD showed no protective effect of blue light-filtering IOLs, with comparable incidence rates across all subgroups.“Despite substantial evidence from in vitro and animal model studies linking blue light-filtering IOLs and AMD, these lenses may fail to demonstrate effectiveness in clinical human studies because blue light exposure in daily life is not a major contributing factor to AMD,” the study authors wrote in their paper.They wondered whether racial characteristics might play a role in AMD risk. South Korea is a predominantly single-ethnicity nation with a universal healthcare and social insurance system. East Asians generally have a higher concentration of melanin pigment in the iris and RPE, which may provide some protection against light-induced retinal damage. Nevertheless, their findings further supported existing evidence that blue-blocking IOLs do not provide a clear protective advantage against wet AMD. The research team called for further research to explore multiethnic populations, longer follow-up periods and other potential benefits of blue light-filtering IOL use.Click here for the journal source. Kim JY, Kim S, Cho J, et al. Exudative AMD risk following blue light-filtering IOL implantation: a population-based study according to nonexudative AMD status. Am J Ophthalmol. July 11, 2025. [Epub ahead of print].