Night exposure of artificial light may increase age-related macular degeneration risk

In a recent nationwide study highlighted the link between exposure to outdoor artificial light at night (OALAN) and the risk of developing exudative age-related macular degeneration (EAMD). The findings of this study published in the JAMA Network Open underline the previously underestimated health impacts of light pollution.

This comprehensive investigation analyzed data from individuals aged 50 or older with newly diagnosed EAMD from January 1, 2010 to December 31, 2011. The study utilized the Korean National Health Insurance Service registration program database for rare and intractable diseases. After matching for birth year and sex, the controls were selected at a 1:30 ratio. The data acquired from May 1 to December 31, 2021 was analyzed from June 1 to November 30, 2022 and presented a robust base for this study.

The study encompassed a total of 126,418 participants and revealed a significant association between increased levels of residential OALAN and an increased risk of incident EAMD. A substantial finding was an HR of 1.67 (95% CI, 1.56-1.78) for incident EAMD with an interquartile range (IQR) increase in the OALAN level (55.8 nW/cm²/sr).

The exposure-response curve displayed a nonlinear, concave upward slope, particularly pronounced at higher levels of light exposure, approximately 110 nW/cm²/sr. In a subgroup analysis, the impact was more significant in urban areas (HR, 1.46 [95% CI, 1.33-1.61]) when compared to rural areas (HR, 1.01 [95% CI, 0.84-1.22]).

These findings highlight the need to recognize the role of light pollution on human health and its potential contribution to EAMD. Due to urbanization and increased artificial lighting the light pollution is on the rise globally and so, this research signals the requirement of more detailed studies.

Source:

Kim, S. H., Kim, Y. K., Shin, Y. I., Kang, G., Kim, S. P., Lee, H., Hong, I. H., Chang, I. B., Hong, S.-B., Yoon, H.-J., & Ha, A. (2024). Nighttime outdoor artificial light and risk of age-related macular degeneration. JAMA Network Open, 7(1), e2351650. https://doi.org/10.1001/jamanetworkopen.2023.51650