From Alzheimer’s to Zebrafish: Eclectic Science and Regulatory Stories 170
It can be argued that among the various illnesses associated with aging, including osteo-
arthritis, osteoporosis, cancer, diabetes, cardiovascular disease and Parkinson’s disease,
none is more dreaded than Alzheimer’s disease. The affected patient suffers a progres-
sive loss of cognitive awareness and his or her independence and eventually dies, usually
within three to nine years after diagnosis.1 Alzheimer’s disease causes the mind to slowly
vanish, leaving an empty shell of a person behind. More troubling, even after years of
research, there remain more questions than answers about Alzheimer’s disease. This is not
surprising, since the brain is the most complex structure in the universe and there is still
much to be learned about its function. While research continues, it is troubling to know
that Alzheimer’s disease may be inevitable for many people. This article is intended to
enhance understanding of the disease by briefly describing its history, incidence, symp-
toms, diagnosis, etiology and current and possible future treatment.
History
The disease that bears his name was first discussed by Alois Alzheimer, MD, (1864–1915)
at a 1906 psychiatry meeting in Tubingen, Germany. He described a peculiar brain
abnormality in one of his patients who died of an unusual mental illness that included
progressive cognitive impairment, focal symptoms, hallucinations and delusions. The
autopsy revealed a thinner cerebral cortex than commonly seen in the elderly, together
with tangled bundles of fibers (now called neurofibrillary tangles) and abnormal clumps
(now called amyloid plaques). He described the latter as extracellular deposits of a neuro-
toxic substance. During his presentation, Alzheimer made the assertion that the patient’s
dementia was likely due to these lesions. His speech was followed by publication of his
findings the following year under the title “A characteristic serious disease of the cere-
bral cortex.”2 The importance of this patient’s case marked the beginning of Alzheimer’s
disease research. The term “Alzheimer’s disease” was coined by Emil Kraepelin in 1910
and first appeared in print in his book, the Handbook of Psychiatry.3 An excellent description
of the clinical and histopathological findings of Alzheimer’s patients was published in The
Lancet in 1997.4
Incidence
As mentioned above, the principal risk factor for Alzheimer’s disease is age. It is a specific
disease that affects about 6% of the population over 65 years of age. The incidence doubles
every five years after that age, with an annual diagnosis of 1,275 new cases per 100,000
people older than 65.5 The odds of being diagnosed with Alzheimer’s disease after 85
years of age exceed one in three. As the elderly population increases, prevalence in the US
will approach 13.2 million to 16 million cases by mid-century.6
Description and Symptoms
Alzheimer’s disease is a chronic, progressive, neurodegenerative disorder characterized
by three primary groups of symptoms. The first group (cognitive dysfunction) includes
memory loss, language difficulties and loss of higher level planning and intellectual
coordination skills. The second group comprises psychiatric symptoms and behavioral
disturbances. The third includes difficulties in performing activities of daily living, e.g.,
driving, shopping, eating unaided. The symptoms progress from mild memory loss to
very severe dementia. Increasingly, the coexistence of vascular disease and Alzheimer’s is
being recognized clinically, pathologically and epidemiologically.7 Alzheimer’s disease is
irreversible. It slowly destroys memory and cognitive skills, and even the ability to carry
out the simplest tasks.8
It can be argued that among the various illnesses associated with aging, including osteo-
arthritis, osteoporosis, cancer, diabetes, cardiovascular disease and Parkinson’s disease,
none is more dreaded than Alzheimer’s disease. The affected patient suffers a progres-
sive loss of cognitive awareness and his or her independence and eventually dies, usually
within three to nine years after diagnosis.1 Alzheimer’s disease causes the mind to slowly
vanish, leaving an empty shell of a person behind. More troubling, even after years of
research, there remain more questions than answers about Alzheimer’s disease. This is not
surprising, since the brain is the most complex structure in the universe and there is still
much to be learned about its function. While research continues, it is troubling to know
that Alzheimer’s disease may be inevitable for many people. This article is intended to
enhance understanding of the disease by briefly describing its history, incidence, symp-
toms, diagnosis, etiology and current and possible future treatment.
History
The disease that bears his name was first discussed by Alois Alzheimer, MD, (1864–1915)
at a 1906 psychiatry meeting in Tubingen, Germany. He described a peculiar brain
abnormality in one of his patients who died of an unusual mental illness that included
progressive cognitive impairment, focal symptoms, hallucinations and delusions. The
autopsy revealed a thinner cerebral cortex than commonly seen in the elderly, together
with tangled bundles of fibers (now called neurofibrillary tangles) and abnormal clumps
(now called amyloid plaques). He described the latter as extracellular deposits of a neuro-
toxic substance. During his presentation, Alzheimer made the assertion that the patient’s
dementia was likely due to these lesions. His speech was followed by publication of his
findings the following year under the title “A characteristic serious disease of the cere-
bral cortex.”2 The importance of this patient’s case marked the beginning of Alzheimer’s
disease research. The term “Alzheimer’s disease” was coined by Emil Kraepelin in 1910
and first appeared in print in his book, the Handbook of Psychiatry.3 An excellent description
of the clinical and histopathological findings of Alzheimer’s patients was published in The
Lancet in 1997.4
Incidence
As mentioned above, the principal risk factor for Alzheimer’s disease is age. It is a specific
disease that affects about 6% of the population over 65 years of age. The incidence doubles
every five years after that age, with an annual diagnosis of 1,275 new cases per 100,000
people older than 65.5 The odds of being diagnosed with Alzheimer’s disease after 85
years of age exceed one in three. As the elderly population increases, prevalence in the US
will approach 13.2 million to 16 million cases by mid-century.6
Description and Symptoms
Alzheimer’s disease is a chronic, progressive, neurodegenerative disorder characterized
by three primary groups of symptoms. The first group (cognitive dysfunction) includes
memory loss, language difficulties and loss of higher level planning and intellectual
coordination skills. The second group comprises psychiatric symptoms and behavioral
disturbances. The third includes difficulties in performing activities of daily living, e.g.,
driving, shopping, eating unaided. The symptoms progress from mild memory loss to
very severe dementia. Increasingly, the coexistence of vascular disease and Alzheimer’s is
being recognized clinically, pathologically and epidemiologically.7 Alzheimer’s disease is
irreversible. It slowly destroys memory and cognitive skills, and even the ability to carry
out the simplest tasks.8