Based on data from two large studies of older Americans, researchers
found those who had problems with distance vision were also two to
three times as likely as those with strong vision to be cognitively
Regular vision screening of older Americans could help to catch
people at greater risk of cognitive problems and dementia, the study
team writes in JAMA Ophthalmology.
“The potential interactions between neurosensory (vision and
hearing) impairment and cognitive impairment are still not very well
understood,” said senior study author Dr. Suzann Pershing, chief of
ophthalmology at the VA Palo Alto Health Care System and a faculty
member at Stanford University School of Medicine in California.
Vision problems affect 1 in 28 Americans older than age 40,
according to the Wilmer Eye Institute in Baltimore. The number of
people with vision problems could double by 2050, largely due to
cataracts, glaucoma and macular degeneration in the nation’s aging
“But (these neurosensory interactions) are increasingly relevant
given a growing U.S. population of older adults,” Pershing told
Reuters Health by email. “We have greater numbers of individuals who
are experiencing diseases and functional limitations of aging as
they grow older.”
The study team analyzed data from nearly 2,975 participants over age
60 in the yearly National Health and Nutrition Examination Survey (NHANES),
as well as more than 30,000 participants over age 65 in the National
Health and Aging Trends Study.
Both studies asked participants about their vision, bothersome
vision problems and other health issues, and both assessed cognitive
impairment and dementia with special tests. NHANES also assessed
eyesight objectively with vision tests.
About one quarter of participants in each of the surveys were found
to have cognitive impairment or dementia.
Most participants in NHANES had good distance vision, with only 9
percent unable to see someone across the street or watch television
across the room. And 14 percent had difficulty with near-vision. But
30 percent said they felt hampered by vision problems in their daily
In the other study group, just 7 percent and 5 percent of
participants, respectively, had distance vision and near vision
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The research team found that having distance vision worse than 20/40
and even the perception of having bothersome vision problems were
associated with almost three-fold higher odds of cognitive
impairment. Near-vision problems were less associated with higher
odds of dementia or cognitive impairment.
“It makes intuitive sense that vision impairment might lead to
social disengagement and speed up cognitive decline,” Pershing said.
“Similarly, cognitive impairment when severe may result in
functional visual impairment, even if the eyes are structurally
The American Academy of Ophthalmology recommends regular eye exams
in older adults. But the U.S. Preventive Services Task Force, a
government-backed panel that weighs medical evidence, concluded in
both 2009 and 2016 that eye screenings don’t lead to enough vision
improvement in older adults to recommend them routinely.
The study results are “a reminder and another potential reason for
patients to monitor and maintain eye health,” Pershing said.
“Be aware of the potential for vision loss either in yourself or in
a family member with dementia or cognitive impairment,” said
Jennifer Evans of the London School of Hygiene and Tropical Medicine
in the UK, who wrote a commentary accompanying the study.
“Much visual impairment at older ages can be treated, either by a
better pair of spectacles or cataract surgery, which is a safe and
effective operation,” Evans said.
SOURCE: http://bit.ly/2wFRuyb JAMA Ophthalmology, online August 17,
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