Blue light-filtering intraocular lenses (IOLs) provide no advantage over non-blue light-filtering IOLs in preventing age-related macular degeneration (AMD), according to a study published in the American Journal of Ophthalmology.
A century ago, scientists hypothesized that cumulative retinal damage could be caused by repetitive acute retinal phototoxicity from exposure to environmental light. More recently, clinicians have seen an increase in the use of blue light-filtering IOLs for their photoprotective benefits, according to researchers, despite clinical confirmation of their efficacy.
To dig deeper, researchers analyzed the incidence rate of AMD after cataract surgery. They compared the relative incidence of AMD in patients who were implanted with blue light-filtering IOLs with those implanted with non-blue light-filtering IOLs. Using the Taiwan National Health Insurance Research Database, the team enrolled 186,591 patients who underwent cataract surgery in both eyes between 2008 and 2013. They followed them from the index date (the date of first cataract surgery) until a diagnosis of AMD, death, loss to follow-up, or December 31, 2017, whichever occurred first.
In total, 21,126 (11.3%) patients had blue light-filtering IOLs and 165,465 (88.7%) received non-blue light-filtering IOL implants. Patients in the blue light-filtering group tended to be younger women with higher incomes, non-manual jobs, lived in urban or suburban settings, and had fewer chronic diseases than the non-blue light filtering group. With a mean follow-up period of 6.1 years (range: 1 to 10 years) after cataract surgery, 12,533 and 1655 patients developed non-exudative AMD and exudative AMD, respectively.
The incidence rate of AMD after cataract surgery was low, with a similar incidence rate among those using blue light-filtering and non-blue light-filtering IOLs. More specifically, the incidence rate of non-exudative AMD and exudative AMD (per 1000 person-years) was 9.95 and 1.22 for the blue light-filtering IOL group and 11.13 and 1.44 for the non-blue light-filtering-IOL group, respectively. After analysis, investigators found no statistical difference in the incidence rate of nonexudative AMD and exudative AMD between the 2 IOL groups.
The study’s authors note several limitations of their work, including that the allocation to IOL groups was not randomized, confounders due to the study’s retrospective nature, the use of ICD codes to identify patients, and that a more extended follow-up period may be more sensitive in detecting the effect of blue light-filtering IOLs on AMD incidence.
Lee J-S, Li P-R, Hou C-H. Effect of blue light-filtering intraocular lenses on age-related macular degeneration: A nationwide cohort study with 10-year follow-up. Am J Ophthal. 2021. doi:10.1016/j.ajo.2021.08.002