Nov. 3 (UPI) — More than 18 million adults ages 40 and older in the United States are living with early-stage, age-related macular degeneration — higher than previous estimates, a new study says.
Researchers said another 1.5 million adult Americans are in the late stages of the incurable eye disease, which is caused by deterioration of the central portion of the retina, called the macula.
Macular degeneration is a leading cause of vision loss and blindness, according to the Centers for Disease Control and Prevention.
“Like earlier studies, our study found that AMD is a highly prevalent eye problem that people should keep in mind as they age,” David B. Rein, the study’s lead author, told UPI in an email.
Rein, who is director of the Public Health Analytics Program at NORC at the University of Chicago, an independent, non-partisan research institution, said the study used a definition of early age-related macular degeneration that included stages that put a person at higher risk of vision-threatening disease, according to the American Academy of Ophthalmology.
“This had the effect of increasing the number of people with early AMD as compared to some earlier estimates ,which used a more conservative definition,” he said.
According to Rein, a main contribution of the study is the creation of state- and county-level estimates of the disease’s prevalence that could help local health officials plan the best strategies to reduce vision loss and blindness in their areas.
The original investigation was published Thursday in JAMA Ophthalmology.
The researchers noted that the prevalence of age-related macular degeneration has not been estimated for the United States in more than a decade, and prevalence estimates for the eye disease in its early stages are scarce and inconsistently measured.
So, the scientists set out to estimate the overall prevalence of early- and late-stage age-related macular degeneration in the United States, then break it down by age, gender, race and ethnicity, county and state.
Various data sources were used, including nationally representative and local population-based studies as well as relevant data from the CDC’s Vision and Eye Health Surveillance System.
For 2019, the researchers estimated that 18.34 million people 40 years and older who were living with early-stage age-related macular degeneration, for a prevalence rate of 11.64%.
An estimated 1.49 million people in the same age range were living with the eye disease in its late stages, for a prevalence rate just under 1%.
Prevalence rates for the eye disease varied by demographic characteristics and geography, ranging from 5.66% in Washington, D.C., to 17.08% in Rhode Island, the investigators found.
And men had a higher prevalence rate than women for early stage age-related macular degeneration, at 12.72% versus 10.73%, respectively, the scientists reported, although they described this estimated difference as “highly uncertain.”
According to the CDC, getting certain vitamins and minerals every day may slow the progression of the disease from the early or middle stages to the later stages.
Specifically, CDC says that combinations of the following vitamins can reduce the risk of late AMD by 25%: Vitamin C, Vitamin E, beta-carotene, zinc and copper. Green, leafy vegetables are a good source of these nutrients, the agency says.
For later stages of the eye disease, therapies such as injections and laser treatment may be used, the CDC said.
