A book like this is possible only because of
advances that are bringing us closer to ways of
the major progress that scientists throughout the
managing and eventually defeating AD.
world have made. Not long ago, we knew very
■ Part 4 focuses on issues important to AD
little about AD other than some facts about its
caregivers and families, including current research major characteristics. Today, we are beginning that is finding ways to improve caregiver support.
to understand more about what AD is and who
The end of the book includes a list of publica-
gets it, how and why it develops, and what course
tions and resources that people with AD, family
it follows. We are learning about the complex
members, and caregivers may find useful as they
interface between AD and normal age-related
live day to day with the disease.
changes in the brain. We also are getting much
Then and Now: The Fast Pace of Developments in AD Research As shown in this timeline, we have learned a lot since Dr. Alzheimer presented the case of his patient, Auguste D.
The pace of research continues to accelerate as new findings open more and more doors to discovery.
19O6
196Os
■ Dr. Alois Alzheimer, a German neurologist and
■ Scientists discover a link between dementia and
psychiatrist, describes the case of a 51-year-old
the number of plaques present in the brain. AD is
woman, Auguste D., who had been admitted to
recognized as a distinct disease, not a normal part
a hospital 5 years earlier with a cluster of unusual
of aging.
symptoms, including problems with comprehension
and memory, an inability to speak, disorientation,
197Os
behavioral problems, and hallucinations. After her
■ Scientists find that levels of acetylcholine, a
death, Dr. Alzheimer examined her brain tissue and
neurotransmitter important in memory formation,
described two of the hallmarks of AD—numerous
falls sharply in people with AD. This discovery is
globs of sticky proteins in the spaces between
one of the first to link AD with biochemical changes
neurons (beta-amyloid plaques) and a tangled
in the brain.
bundle of fibrils within neurons (neurofibrillary
■ “Alzheimer’s disease” becomes a common term as
tangles).
recognition of AD as a major public health problem
grows.
191Os – 194Os
■ NIA is established.
■ Belief persists that “senile dementia” is a normal part
of aging.
198Os
■ Diagnostic criteria for AD are established.
195Os
■ Genetic links to early-onset AD begin to surface.
■ Scientists study the biological structure of plaques
■ Congress mandates NIA as lead Federal agency
and tangles.
for AD research.
6 ALZHEIMER’S DISEASE Unraveling the Mystery
better at diagnosing it early and accurately. Most function in healthy older people and identified important, we now have some promising leads on ways we might lessen normal age-related declines possible treatments. Studies also are beginning
in mental function. Most importantly, this accu-
to focus on preventive strategies by examining
mulated research has increased our appreciation
lifestyle factors that might influence a person’s
for just how complex AD is. It is now clear that
risk of developing AD.
many scientific and clinical disciplines need to
Since the 1970s, research supported by
work together to untangle the genetic, biological,
NIA and other organizations has deepened
and environmental factors that, over many
our understanding of this devastating disease.
years, set a person on a course that ultimately
It also has expanded our knowledge of brain
results in AD.
■ Scientists start to unravel the biological pathways
2OOOs
that lead to the development of beta-amyloid
■ The FDA approves other AD drugs, including
plaques in the brain.
rivastigmine (Exelon®), galantamine (Razadyne®),
■ Abnormal tau protein in tangles is identified.
donepezil (Aricept®), and memantine (Namenda®)
to treat symptoms of AD.
199Os
■ Early work on an AD vaccine begins.
■ The U.S. Food and Drug Administration (FDA)
■ Many new AD clinical trials, initiatives, and
approves tacrine (Cognex®), the first drug used to
studies are launched, looking at a broad array of
treat AD. This drug has since been replaced by
translational, treatment, and prevention issues.
other medications.
■ New transgenic mouse models, including one
■ Genetic mutations linked to early-onset and
that develops both plaques and tangles, are
late-onset AD are discovered.
developed.
■ The first transgenic mouse model of AD is
■ Pittsburgh Compound B (PiB) is developed, allowing
created.
researchers to “see” beta-amyloid plaques in the
■ Additional diagnostic criteria are developed for AD.
brains of living people.
■ Characteristics of mild cognitive impairment are
■ The growing sophistication of neuroimaging
described and defined.
techniques, genetics, memory and cognitive
■ NIA launches the Alzheimer’s Disease Education
tests, structured interviews, and other technologies
and Referral Center, AD Cooperative Study, and
improve our ability to identify people at high
other initiatives to conduct and support AD treatment
risk of AD.
and prevention clinical trials.
ALZHEIMER’S DISEASE Unraveling the Mystery 7
