Title: Epidemiology of Alzheimers Disease
1Epidemiology ofAlzheimers Disease
Carla Falkenstein, MS
2Course Content
- Description of the disease process.
- Possible etiology based on population studies.
- Global prevalence.
3What is Alzheimers Disease?
- Neurodegenerative disease.
- Most common form of dementia.
- Causes impaired cognitive functioning.
- No known cure.
4Diagnosis of AD
- Because it is a progressive disease with one of
the earliest symptoms being memory loss,
diagnosis is difficult.
5Common Symptoms
- Forgetting names and objects.
- Not recognizing family friends.
- Forgetting ones own phone number or address.
- Difficulty finding a familiar place.
- Noticeable language intellectual decline.
6Common Symptoms (contd)
- Forgetting to eat or maintain ones hygiene.
- Poor judgment, inability to follow simple
instructions. - Progressive sense of distrust.
- Unusual agitation and irritability.
7Age is a Primary Risk Factor
Ages Prevalence 65-74 3 75-84 18.7 85
47
8Stages of AD
SEVERE 1-3 Years
MODERATE 2-10 Years
MILD 2-4 Years
9Disease Process
10Disease Process (contd)
- 1st destroys neurons in parts of the brain that
control memory. - Later attacks cerebral cortex - areas responsible
for language and reasoning. - Eventually nearly the entire brain is atrophied.
11Cause of Nerve Cell Death
- Amyloid Plaques?
- Neurofibrillary Tangles?
12Amyloid Plaques
- Insoluble deposits of beta-amyloid
- Plaques found in the spaces between the brains
nerve cells - Plaques may be a cause or a by-product of AD
13Neurofibrillary Tangles
- Twisted threads of a protein called tau.
- Tau is a protein found inside nerve cells.
- In AD, Tau changes so that it becomes 2 threads
wound around each other.
14Other Genetic Factors
APOE ?4 allele of the APOE gene is a major risk
factor for late-onset AD. However, much work is
being done to sort out all the potential genetic
factors involved in AD.
15AD and Other Disorders
- AD has similarities with other neurodegenerative
diseases - Prion, Parkinsons and Huntingtons diseases all
cause dementia. - All involve deposits of abnormal proteins in the
brain.
16Early Diagnosis
- The earlier a correct diagnosis can be made, the
greater the gain in managing symptoms through
pharmaceuticals. - MRI
- PET
- SPECT
17Causal vs. Associative Agents
- Advanced age
- Female gender
- Head Injury
- Cerebrovascular disease
- Low education levels
- Rural Residence
- Blood cholesterol
- Low blood levels of folic acid
- Inflammation
18A Chain of Events Leads to
Disability and Death
GENES
LIFESTYLE ENVIRONMENT
BRAIN DEVELOPMENT RESERVE
ALZHEIMERS SEVERITY IN BRAIN
NEURO- DEGENERATION
OTHER DISEASES
AGE AT ONSET OF SYMPTOMS
SEVERITY OF SYMPTOMS
19Global Prevalence of AD
- United States
- Most common cause of AD
- Current cases 4 million
- Prevalence doubles every 5 years beyond age 65
- Nearly 50 of those aged 85 have AD
20Global Prevalence of AD
- African Americans in Indianapolis are twice as
likely as Africans in Ibadan, Nigeria to develop
dementia AD. - Higher rates of AD in Japanese men who emigrated
to US compared with those who remained in Japan.
21Global Prevalence of AD
Europe There are currently an estimated 5.5
million people with dementia in Europe.
22Global Prevalence of AD
Developing Countries Currently, 18 million
people in the world have dementia. 66 of
people with dementia live in developing countries.
23Current Research
- Continued search for causative agents and
etiology. - Disease prevalence worldwide with close attention
to cultural variations. - Animal and population studies that confirm
causation and lead to preventive or curative
measures.