Mr. Chairman, I am pleased to report
that the NEI continues to conduct and
support research leading to treatment for
blinding eye diseases, including glaucoma,
cataracts, and diabetic retinopathy.
Furthermore, we also are pursuing exciting
new avenues of research for one particular
eye disease that is causing increased
concern among older Americans , age
related macular degeneration, or AMD.
The American eye is aging. The first
group of "baby boomers" , those born
between 1946 and 1964 , turned 50 last
year. This group, by their sheer numbers,
has changed, and continues to change, the
fabric of American society. In 1995, these
"baby boomers" numbered more than 79
million.
As this group of Americans marches
toward their golden years, they will become
more susceptible to serious eye diseases,
such as AMD. AMD is a common eye
disease of the macula, a tiny area in the
retina that helps produce sharp, central
vision required for "straight ahead"
activities such as reading, sewing, and
driving. A person with AMD loses this
clear, central vision. AMD is the leading
cause of severe visual impairment and
blindness in the United States. It is
estimated that AMD already causes visual
impairment in approximately 1.7 million of
the 34 million Americans over age 65, and
its prevalence is expected to reach 6.3
million by the year 2030. Since fiscal year
1989, the NEI has devoted an increasing
percentage of its annual appropriation to
AMD research.
Technology has advanced greatly in
recent years, and as a result, the NEI has
identified several areas of research to learn
what causes AMD and how it can be
treated more successfully. Through NEI's
Age-Related Eye Disease Study,
researchers at 11 clinical centers around the
country are assessing the aging process,
potential risk factors, and quality of life of
4700 patients to pinpoint the earliest signs
of AMD. Once such studies have helped us
to determine how macular degeneration
develops, we might be able to change its
course; when we know for certain what risk
factors contribute to development of the
disease, we can caution patients to avoid
them. This same study also includes
clinical trials that will help determine the
effects of certain vitamins and minerals in
preventing or slowing the progress of
AMD. In particular, researchers are
examining whether vitamins C and E, beta-carotene, and zinc can provide the macula
with greater protection, thereby preventing
or slowing progression of the disease. If
dietary supplements prove effective, it
would have a huge impact on AMD
treatment and reduce our nation's risk of
visual impairment or blindness.
Another study begun last year is
evaluating genetic and environmental
factors related to AMD and examining an
underlying hypothesis that genetic factors
play a significant role in this complex
chronic disease. Participating families in
this study include those with both a single
case of documented AMD and those who
have at least two living siblings (or a
parent) with documented AMD.
One of the risk factors that may be
associated with AMD and vision loss is the
presence of drusen, which are white,
clumpy deposits that lodge under the retina.
Early investigations suggest that these
deposits might be a precursor to AMD, and
this hypothesis is undergoing careful study
to determine if drusen play a role in the
development of macular degeneration.
Other approaches to solving the
problem of AMD include laboratory, or
basic, research. This research includes
studies of genetic factors to gauge the role
of heredity in the development of AMD.
Genes involved in AMD already have been
identified in three less common types of
macular degeneration. In addition, genes
associated with several other forms of
macular degeneration have been localized
to specific chromosomes. Knowing the
genes will enable researchers to determine
the gene product and how it brings about
the degeneration.
NEI scientists also are trying to identify
genes that could help regenerate damaged
areas of the retina. This strategy may help
to prevent much of the visual loss from
later stages of AMD. Researchers are
exploring the effects that gene replacement
therapy may have on the treatment of
macular degeneration, and scientists have
already successfully placed genes into the
retina of laboratory animals. Replacing
diseased retinal cells with healthy ones is
another promising area of research. NEI
scientists are working to apply retinal cell
transplants to treat retinal degeneration
caused by AMD.
The NEI also sponsored a workshop
that led to shared research ideas and
consideration of the future direction of
AMD research. This workshop, held last
June, brought together academicians,
clinicians, and representatives from
biotechnology companies, all of whom
were knowledgeable in growth factor cell
biology. The discussion centered around
the potential use of neurotrophins, or
biological survival factors, to delay clinical
indications of retinal cell degeneration in
AMD and other eye diseases.
In addition to being a leading cause of
blindness in the United States, AMD is also
a leading cause of low vision, broadly
defined as a visual impairment interfering
with an individual's ability to perform
activities of daily living. There are
approximately three million Americans
who suffer from visual conditions that are
not correctable by standard glasses or
contact lenses. People with low vision
often cannot perform daily routine
activities, such as reading the newspaper,
preparing meals, or recognizing faces of
friends.
As the leading source of vision research
funds in the United States, the NEI is
committed to furthering progress in the
area of low vision research. During 1996,
the NEI supported 18 extramural research
projects related to low vision. In addition,
the NEI, through the National Eye Health
Education Program, is developing an
education program aimed at addressing the
needs of people with low vision. This new
program will increase public awareness
about the impact of low vision on daily
living. Approximately 21 percent of those
who have low vision and are aged 45 and
older are unfamiliar with low vision
clinical services. The low vision program
will play a key role in informing
Americans about the use of optical and
adaptive low vision devices and services.
The NEI has been very active in
pursuing treatments for a wide spectrum of
eye diseases, including those affecting the
youngest Americans. Last year we
confirmed that a freezing treatment helps
save the sight of premature babies with a
potentially blinding condition called
retinopathy of prematurity. After 5� years
of follow-up, this treatment increased the
possibility of saving sight in affected eyes
by about 24 percent. These results present
solid evidence that this freezing treatment
significantly reduces the number of infants
who are blinded by retinopathy of
prematurity.
NEI's fight against uveitis, a severe
inflammation in the eye, is continuing.
Uveitis causes about 10 percent of the
severe visual impairment in the United
States, and affects primarily children and
young adults. Treatment of uveitis has
usually revolved around potent drugs that
block the immune system. In a recent
intramural NEI study, we found that when
a purified protein is fed to patients
suffering from uveitis, they were able to be
weaned off the strong drugs, with no
negative side effects. A larger, more
focused clinical trial is underway.
The NEI is also studying the effect of
apoptosis, or "cell suicide," in retinal
degeneration. Apoptosis is a controlled,
orderly process by which the body
eliminates unwanted cells; it is a
mechanism to eliminate damaged cells,
without harming healthier neighbors.
Apoptosis appears to play a role in several
retinal degenerative diseases. By
understanding the process by which this
programmed cell death occurs, scientists
may be able to develop a method to inhibit
the process and thus treat these diseases.
The NEI also is active in the area of cell
rescue and regeneration. Severed nerve
cells in the peripheral nervous system can
survive and regenerate to some extent, but
most central nervous system nerve cells do
not. For years researchers have been trying
to determine the basis for this difference, so
that damage to either system could be
repaired. Recent research on the
development of the visual system indicates
that the signals that promote the survival
and growth of neurons in the central
nervous system and peripheral nervous
system may differ significantly. Studies
have demonstrated that specialized nerve
cells in the retina that are similar to brain
cells, including those cells in the spinal
cord, do not survive in a serum-free culture
medium. However, these cells do survive
in culture when the medium contains the
required combination of growth factors and
other constituents. Related experiments in
animals show that the survival of these
specialized retinal cells after damage is
significantly increased by injection of these
factors into the eye. These findings
demonstrate that the retinal nerve cells
have similar survival requirements in the
living organism and in the test tube,
suggesting central nervous system neurons
can be rescued by activating the
appropriate signaling pathways.
As the NEI continues its research, it is
becoming apparent that many eye diseases
and disorders share common denominators.
For example, new blood vessel growth in
the retina is associated with both diabetic
retinopathy and age-related macular
degeneration. The NEI is looking at the
way these pathologic processes cut across
many diseases and can be controlled by
blocking new blood vessel growth.
Our investment in high quality clinical
research has little real benefit unless the
results and recommendations from such
studies are widely and suitably
incorporated into patient care. Results of
research must be disseminated to the public
so people can take more proactive
approaches to ensure their own health. One
way this happens is through the National
Eye Health Education Program (NEHEP),
which is playing a role in educating
Americans on the early detection and
treatment of eye disease. For the past three
years the National Eye Institute, through
the NEHEP, has joined forces with the
American Diabetes Association to make
diabetic eye disease the major focus of
National Diabetes Month activities, held in
November. Through this successful public-private partnership, 11 organizations have
disseminated important information to the
16 million Americans with diabetes and
conducted community activities nationwide
that emphasized the importance of an
annual dilated eye examination. A related
media campaign focusing on the
connection between diabetes and eye care
reached over 80 million people.
NEI's research program does more than
fight eye disease , it also helps inventors
with ideas on low vision aids develop those
ideas for the marketplace. Inventors have
few resources available allowing them to
develop products that help people suffering
from low vision. NEI's Small Business
Innovation Research Grants Program gives
inventors the opportunity to see their ideas
turned into reality. For example, through
this program, telescopic systems were
developed that help those with low vision
perform common tasks, such as walking
down the street or reading signs. Another
idea, a system called "Outspoken,"
magnifies text on a computer screen,
making it easier for people with low vision
to read. This product was recognized by
the Smithsonian Institution for its unique
way of using technology for the common
good. A sister program, called the Small
Business Technology Transfer Grant,
encourages inventors in universities or
research centers to form partnerships with
small businesses. Between both programs,
NEI expects to fund approximately 50
projects this fiscal year.
Mr. Chairman, the fiscal year 1998
budget request for the National Eye
Institute is $330,955,000. I will be happy
to answer your questions.