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Glaucoma
Glaucoma is a disease that causes a gradual degeneration of cells that make
up the optic nerve which carries visual information from the eye
to the brain. As the nerve cells die, vision is slowly lost, usually beginning in the
periphery. Often, the loss of vision is unnoticeable until a significant amount of
nerve damage has occurred. For this reason, as many as half of all people with
glaucoma may be unaware of their disease.
The exact cause of primary open-angle glaucoma, the most common form of
the disease, is uncertain. Other forms of glaucoma (such as angle-closure,
secondary and congenital glaucoma) occur in relation to specific physical
causes.
Elevated fluid pressure within the eye (intraocular pressure) seems related in
some way to all cases of glaucoma. The majority of cases of glaucoma exhibit
intraocular pressure outside normal limits at some time. However, even those
cases with apparently normal pressure seem to benefit from treatment aimed
at lowering pressure.
Most cases of glaucoma can be controlled and vision loss slowed or halted by
treatment. Medications, laser treatments and surgery can be used to lower
intraocular pressure. However, any vision lost to glaucoma cannot be restored.
Unfortunately, glaucoma cannot be prevented. Factors that increase the risk of
glaucoma include age, race, diabetes, eye trauma, and long-term use of steroid
medications.
Glaucoma is traditionally defined by a triad of signs, including the presence of at
least two of the following: elevated intraocular pressure, optic disc cupping, and
visual field loss. However, case definitions used in the various epidemiologic
studies of the disease have differed on specific criteria. Only cases of primary
open-angle glaucoma that had clear signs of optic nerve head damage and/or
reproducible visual field loss (definite open angle glaucoma) are included in the
prevalence estimates.
The table below lists state-by-state prevalence estimates for
glaucoma by race and sex. Glaucoma affects more than 2.2 million Americans
age 40 and older, or about 1.9% of this population. Glaucoma prevalence is clearly
related to age and race. In general, glaucoma is more common in Blacks, Hispanics
and with increasing age.
In the 65-69 age group, the prevalence rate for White females is about 1.6%,
while in Black females, the rate is three times higher at 4.8%. For those age
80 and older, glaucoma affects more than 10% of Black men and Hispanic
women.
Glaucoma appears to be more common initially in women, but by age 65,
prevalence becomes more comparable between the sexes.
Available tables:
- Estimated Number of Cases of Definite Primary Open Angle Glaucoma in the U.S. by State, Race and Sex
- Prevalence Rates for Definite Primary Open Angle Glaucoma by State, Race and Sex
- National age-specific prevalence rates for definite primary open angle glaucoma
- U.S. Census 2000 Population aged 40 and over by Race and Sex
The tables are located on the following page:
Notes:
- The page opens in a new window.
- There are 4 tabs located in the bottom left corner that select the different tables.
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