Study shows possible link between artificial outdoor light pollution and eye disease in older adults
Times Square at night on December 15. Credit: Getty Images for Trickster/Eugene Gologursky
Exposure to outdoor artificial light at night could be linked to the onset of age-related macular degeneration, a chronic condition that is a leading source of irreversible blindness, South Korean researchers said.
The risk of getting exudative age-related macular degeneration, also known as the wet form of the disease, in older residents was higher in urban areas of South Korea — which had three times the mean level of outdoor artificial light at night — than in rural areas, according to the research published Tuesday in the Journal of the American Medical Association.
The research said 3.7% of urban dwellers included in the study developed the condition, while that figure was 2.5% in rural areas. The retrospective study used data — including from the Korean National Health Insurance Service database — to analyze more than 120,000 participants. More than 4,000 were diagnosed with the condition.
Researchers say the study also underscores others that show outdoor artificial light at night could also have a negative impact on conditions such as sleep disorders, cardiovascular diseases and mental disorders by disrupting sleep patterns in the body.
Moreover, the findings could have implications for those in or near the New York City region — an area with a significant amount of light pollution. But experts caution that the study's findings have significant limitations, including not measuring the impact of artificial light inside a residence, and say that additional research is needed.
Dr. Matthew Gorski, an ophthalmologist with Northwell Health, called the study “interesting” but said it’s too early to say whether it should prompt people to change their behavior.
“Additional studies, if they show similar results, may cause us to give different recommendations about exposure” to artificial light at night, said Gorski, an assistant professor of Ophthalmology at Hofstra University's Zucker School of Medicine.
Based on the findings in this study, Dr. Khurram Chaudhary, director of retina service at Stony Brook Medicine, said it's too early to tell anybody to “turn off their lights” or change “my clinical practice — yet.”
“But it does open my eyes a little bit …[to] keep an eye out for these [future] studies,” said Chaudhary, a vitreoretinal surgeon who works to get patients’ vision back and to prevent them from going blind.
Age-related macular degeneration, also known as AMD, is a common cause of vision loss in the United States and generally impacts people over 60.
In 2019, about 20 million Americans 40 and older were estimated to have age-related macular degeneration, according to the Centers for Disease Control and Prevention.
There are two kinds of the condition: the wet version that was looked at in the study and a dry form that is generally more common.
The dry kind typically progresses slowly, possibly taking years before a person loses their vision, physicians say. In the wet version, a person can lose vision very quickly, perhaps in days or months.
Symptoms of the condition include blurriness in the center of vision or distorted vision where straight lines appear wavy, said Gorski.
Risk factors include cigarette smoking, high blood pressure and high cholesterol, he said.
But genetics can also play a significant role, said Chaudhary. Women, he said, typically get it more. White people and, more generally, people with light eyes and hair also tend to get the condition more.
“So those are the risk factors you can't really change in yourself … genetically,” he said. “However, if you are a smoker, that also increases your risk significantly, and that is one of the risk factors you can control.”
Even if someone is diagnosed with the condition, it doesn’t mean they are going to lose their vision, Gorski said.
“So I always tell patients just because they're diagnosed with macular degeneration does not mean that they're going to go blind,” he said.
But he said it's still important for people to get an annual eye exam and visit a physician if they have vision changes, red eyes, or experience eye pain.
Exposure to outdoor artificial light at night could be linked to the onset of age-related macular degeneration, a chronic condition that is a leading source of irreversible blindness, South Korean researchers said.
The risk of getting exudative age-related macular degeneration, also known as the wet form of the disease, in older residents was higher in urban areas of South Korea — which had three times the mean level of outdoor artificial light at night — than in rural areas, according to the research published Tuesday in the Journal of the American Medical Association.
The research said 3.7% of urban dwellers included in the study developed the condition, while that figure was 2.5% in rural areas. The retrospective study used data — including from the Korean National Health Insurance Service database — to analyze more than 120,000 participants. More than 4,000 were diagnosed with the condition.
Researchers say the study also underscores others that show outdoor artificial light at night could also have a negative impact on conditions such as sleep disorders, cardiovascular diseases and mental disorders by disrupting sleep patterns in the body.
Moreover, the findings could have implications for those in or near the New York City region — an area with a significant amount of light pollution. But experts caution that the study's findings have significant limitations, including not measuring the impact of artificial light inside a residence, and say that additional research is needed.
Dr. Matthew Gorski, an ophthalmologist with Northwell Health, called the study “interesting” but said it’s too early to say whether it should prompt people to change their behavior.
“Additional studies, if they show similar results, may cause us to give different recommendations about exposure” to artificial light at night, said Gorski, an assistant professor of Ophthalmology at Hofstra University's Zucker School of Medicine.
Based on the findings in this study, Dr. Khurram Chaudhary, director of retina service at Stony Brook Medicine, said it's too early to tell anybody to “turn off their lights” or change “my clinical practice — yet.”
“But it does open my eyes a little bit …[to] keep an eye out for these [future] studies,” said Chaudhary, a vitreoretinal surgeon who works to get patients’ vision back and to prevent them from going blind.
Age-related macular degeneration, also known as AMD, is a common cause of vision loss in the United States and generally impacts people over 60.
In 2019, about 20 million Americans 40 and older were estimated to have age-related macular degeneration, according to the Centers for Disease Control and Prevention.
There are two kinds of the condition: the wet version that was looked at in the study and a dry form that is generally more common.
The dry kind typically progresses slowly, possibly taking years before a person loses their vision, physicians say. In the wet version, a person can lose vision very quickly, perhaps in days or months.
Symptoms of the condition include blurriness in the center of vision or distorted vision where straight lines appear wavy, said Gorski.
Risk factors include cigarette smoking, high blood pressure and high cholesterol, he said.
But genetics can also play a significant role, said Chaudhary. Women, he said, typically get it more. White people and, more generally, people with light eyes and hair also tend to get the condition more.
“So those are the risk factors you can't really change in yourself … genetically,” he said. “However, if you are a smoker, that also increases your risk significantly, and that is one of the risk factors you can control.”
Even if someone is diagnosed with the condition, it doesn’t mean they are going to lose their vision, Gorski said.
“So I always tell patients just because they're diagnosed with macular degeneration does not mean that they're going to go blind,” he said.
But he said it's still important for people to get an annual eye exam and visit a physician if they have vision changes, red eyes, or experience eye pain.
Education: Howard University
Tiffany Cusaac-Smith came to Newsday in 2023 after being a race and history reporter at USA TODAY, where she wrote enterprise and spot articles examining how the past shapes the present. Previously, she worked as the race and justice reporter at the USA TODAY Network of New York, covering issues such as criminal justice reform, housing, environmental justice, health care and politics. At The Journal News/lohud.com in Westchester County, she covered Yonkers, the state's third-largest city. She also worked at The Associated Press in Atlanta.
Honors and Awards: Criminal justice reporting fellowship with the National Press Foundation; New York News Publishers Association award for distinguished investigative reporting; Contributed reporting for Best of Gannett honor; Member of Table Stakes, a program funded by the Knight-Lenfest Local News Transformation Fund and managed by the American Press Institute to transform local news.
