How common is vision impairment?
Vision
impairment is not very common among children.
To learn just how common it is, CDC is tracking the number of children with
vision impairment in a five-county area in metropolitan
Atlanta, Georgia. This activity is part of the Metropolitan Atlanta Developmental Disabilities Surveillance Program
(MADDSP). In 1996, an estimated 1.4 per 1,000 8-year-olds in metro Atlanta,
or about 1 in 715, had vision impairment. In 2000, the prevalence was an
estimated 1.2 per 1,000, or about 1 in 833, 8-year-olds. About one half
(2000) to two thirds (1996) of children with vision impairment also had
one or more other developmental disabilities tracked by MADDSP. [Read more about MADDSP]
CDC also studied how many children in
metropolitan Atlanta were legally blind in the mid-1980s. This project
was done as part of the Metropolitan Atlanta Developmental Disabilities
Study (MADDS), which studied how common certain disabilities were in
10-year-old children. We found that nearly 7 of every 10,000
children 10 years of age had legal blindness. Two-thirds of the children also had another
disability, such as mental retardation, cerebral palsy, or epilepsy.
[Read a summary of the article about
legal blindness in MADDS]
[Read more about MADDS]
Vision impairment is more common in older
people than in children..
A 2002 report by the National Eye Institute and Prevent Blindness America estimates that more than
1 million people ages 40 years or older in the United States are blind (best corrected visual acuity of 20/200 or worse or a visual field of less than 20 degrees).
Another 2.4 million are visually impaired (best corrected visual acuity of 20/40 or worse).
The report states that the number of adults with vision impairment likely
will double over the next 30 years. [Read the report on adult vision
impairment]
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What
causes vision impairment? Can it be prevented?
Vision impairment can be caused by damage
to the eye itself that affects its ability to receive or process
visual information. Impairment can also be due to the eye being
shaped incorrectly, which can make it harder to focus on things.
Vision impairment can also occur if the brain does not process visual
information correctly. Vision impairment can
occur anytime during a person's life, even before birth.
CDC studied the causes of low vision and
blindness in 3- to 10-year old children in metropolitan Atlanta, Georgia.
We found that most of the causes happened before the child was born or
before they were 1 month old. The most common cause was retinopathy
of prematurity (ROP), which refers to abnormal blood vessel growth or
scarring of the retina of the eye. Children who are born very early
or who have very low birth weight are most at risk of having this
condition.
ROP usually gets better on its own before severe damage can occur, and if
not, it can often be treated. However, a small percentage of children
with ROP have a severe form and will have low vision or blindness. Other common causes of
vision impairment found in the CDC study were albinism (a genetic condition
that results in decreased skin pigmentation and affects parts of the eye), hydrocephalus (a condition in which there
is too much fluid in the brain), congenital cytomegalovirus (a viral infection
that occurs before a baby is born), and birth asphyxia (where a baby does
not get enough oxygen before or during birth). [Read
a summary of the article about causes of vision impairment in children]
The most common causes of vision
impairment among adults in the United States are diabetic retinopathy,
age-related macular degeneration, cataracts, and glaucoma. Diabetic
retinopathy is a common complication of diabetes in which the blood vessels
in the retina break down, leak, or become blocked, leading to vision
impairment. Age-related macular degeneration affects the part of the
retina that is responsible for sharp central vision. Cataracts are a
clouding of the eye's lens, which is normally clear. Glaucoma is
increased fluid and pressure within the eye that leads to enlargement of
the eyeball. The risk of vision loss from many of these conditions can
often be reduced if the condition is found early and treated. [Read
more about the causes of vision impairment in adults]
If you would like to learn more about a specific genetic condition that you think
could cause vision impairment, you can go to the National Library of Medicine's Genetics Home Reference Web site. Information on each genetic condition includes symptoms, how common it is, related genes, treatments, and links to resources where you can learn more about the condition. The Genetics Home Reference also can help you learn more about genetics, including genetic testing, genetic counseling, and gene therapy.
[Go to the Genetics Home Reference Web
site]
You can search for CDC guidelines on
preventing vision impairment by visiting the "CDC Recommends: The
Prevention Guidelines System" Web site. The guidelines include
information about vision problems caused by diabetes, infections, eye injuries
caused by fireworks, and other topics. [Go
to CDC Recommends: The Prevention Guidelines System. Enter
"blindness" or "low vision" in the Search For box, then click the
"Search" button.]
Healthy People 2010 is a national effort
to promote health and prevent disease. It includes goals related to
vision impairment, such as preventing eye injuries, increasing the number
of people who have their eyes examined, decreasing the number of children
under 17 years old who are blind or visually impaired, decreasing the
number of people who lose their vision due to diabetes, and others. The
National Eye Institute (NEI) has created a Web site named "Healthy
Vision 2010" that provides more information about the vision-related
goals in Healthy People 2010. [Learn
more about Healthy Vision 2010]
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References
Batshaw ML. Children with disabilities (4th edition). Baltimore MD: Paul H. Brookes Publishing
Co.;1997.
Holbrook MC (Editor). Children with
visual impairments: a parents' guide. Bethesda, MD: Woodbine
House; 1996.
Mervis CA, Yeargin-Allsopp M, Winter S,
Boyle C. Aetiology of childhood vision impairment, metropolitan
Atlanta, 1991-93. Paediatric and Perinatal Epidemiology
2000;14:70-77. [Read
abstract of this paper]
Prevent Blindness America and the National
Eye Institute. Vision problems in the U.S.: prevalence of adult
vision impairment and age-related eye disease in America, 2002. [Read
report]
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What is the cost or economic
impact associated with vision impairment?
Many people with vision impairment need
long-term services. The average lifetime cost for one person with vision
impairment is estimated to be $566,000 (in 2003 dollars). This represents
costs over and above those experienced by a person who does not have a
disability.
It is estimated that the lifetime costs
for all people with vision impairment who were born in 2000 will total $2.5
billion (in 2003 dollars). These costs include both direct and indirect
costs. Direct medical costs, such as doctor visits, prescription drugs, and
inpatient hospital stays, make up 6% of these costs. Direct nonmedical
expenses, such as home modifications and special education, make up 16% of
the costs. Indirect costs, which include the value of lost wages when a
person dies early, cannot work, or is limited in the amount or type of work
he or she can do, make up 77% of the costs.
These estimates do not include other
expenses, such as hospital outpatient visits, emergency department visits,
and family out-of-pocket expenses. The actual economic costs of vision
impairment are, therefore, even higher than what is reported here.
[Return to Topics]
References
Centers for Disease Control and
Prevention. Economic costs associated with mental retardation, cerebral
palsy, hearing loss, and vision impairment --- United States, 2003. MMWR
2004;53:57-9. [Read
this article on economic costs]
Honeycutt AA, Grosse SD, Dunlap LJ,
Schendel DE, Chen H, Brann E, al Homsi G. Economic costs of mental
retardation, cerebral palsy, hearing loss, and vision impairment. In:
Altman BM, Barnartt SN, Hendershot GE, Larson SA, editors. Using survey
data to study disability: results from the National Health Interview Survey
on Disability. Research in social science and disability, volume 3.
Amsterdam: Elsevier; 2003. p. 207-28.
Date: October 29, 2004
Content source: National Center on Birth Defects and Developmental
Disabilities