3. Most common degenerative disease of the brain
In 1907, Alzheimer described the case of a 51-year-old woman who died after
a 5-year illness characterized by progressive dementia.
4. Epidemiology
Most patients above 60 years of age
Incidences: 125 new cases per 100,000 of those older than age 60 years
Prevalence: per 100,000
300 in the group aged 60 to 69 years; it
3,200 in the 70- to 79-year-old group
and 10,800 in those older than age 80.
more than 30 million persons with Alzheimer disease in the world.
5. Epidemiologic risk factors
Birth order
mother’s age at birth
family history of Down syndrome
Depression
Head injuries
Lower educational status
Inheritance
6. Clinical Features
Early presentation with one of following:
Amnesia
Dysnomia
Visiospatial disorientation
Paranoia and personality changes
Impaired Executive function
7. Clinical Features
Insidious onset
May manifest as unusual degree of confusion during and following a federal illness operationor a mild
head, injury
Dizziness, mental forgiveness non-descript, headaches and vaguely expressed somatic symptoms
Gradual development of forgetfulness
Remote memories are preserved. Recent once are lost
8. Clinical Features
Halting speech
Interruption in writing
Restricted vocabulary
Expressive language becomes stereotyped and inflexible
Comprehension is preserved
Failure to speak in full sentence
Echolalia, nominal aphasia
Paucity of speech, reduction in mentation
9. Loss of arithmetics skill
Visuospatial disorientation- person may get lost
Failure to use common object and tools- cannot use a razor
Only most habitual and automatic actions are preserved in late stages
Ideational and ideal motor apraxia
10. Neglect of dressing, saving
Anxiety, restlessness, inertia or placidity
Disturbance in sleep patterns
Delusion, hallucinations
Infatuation with younger person
Eating maybe the neglected or appetite may increase
Grasping and soaking reflexes may appear
Incontinence, akinesia and mutism
11. Symptomatic course of illness 5 or more years
Pre-clinical asymptomatic phase is longer
Stepwise declining memory and attention span
Corticospinal and corticosensory function intact
Visual acuity, ocular movement and visual fields intact
No hemiparesis, hemiplegia or other focal neurological deficit
Planter are flexor.
There is no sensory or cerebellar ataxia
Tendon reflexes are mostly normal
13. Diagnostic criteria
(1) dementia defined by clinical examination, the Mini-Mental Scale/, the
Montreal Cognitive Assessment/Alzheimer Disease Assessment Scale (ADAS)
(2) patient older than age 40 years
(3) deficits in two or more areas of cognition and progressive worsening of
memory and other cognitive functions, such as language, perception, and
motor skills (praxis)
(4) absence of disturbed consciousness
(5) exclusion of other brain diseases
14. biomarkers such as positron emission tomography (PET) ligand for amyloid
tau/amyloid ratio in CSF
15. Pathology
Macroscopic:
Diffuse atrophy of brain
Brain weight reduced by 20 percent or more
Cerebral convolutions narrowed, sulci widened
Third and lateral ventricles enlarged symmetrically
Microscopic:
Wide spread loss of nerve cells- most pronounced in layer II of entorhinal
cortex.
Also in parahippocampal gyri, subiculum, nucleus basilis of Meynert,
Astrocytic hypertrophy
16. Pathology
Essential neuropathologic changes of AD include the following:
●Extracellular deposits of amyloid beta peptides
●Neuritic plaques, associated with neuronal injury and characterized by
amyloid formed from amyloid beta with dystrophic neurites
●Neurofibrillary degeneration, best exemplified by neurofibrillary tangles
17.
18. Cerebral amyloid angiopathy
Inclusions of abnormal alpha-synuclein accumulation /(Lewy body)
Hippocampal sclerosis (HS)/ (FTLD)
Immunoreactive inclusions of TAR DNA binding protein 43 (TDP-43)/ (ALS)
21. Pathogenesis
overproduction and/or decreased clearance of amyloid beta peptides-
their small aggregates called oligomers
Accumulation of tau protein, which becomes hyperphosphorylated and
aggregates to form paired helical filament (PHF)- a major component
of neurofibrillary tangles
Inheritance of APOE e4 --> impairment of amyloid beta clearance
from cerebrum.
reduced cerebral content of choline acetyltransferase, which leads to a
decrease in acetylcholine synthesis and impaired cortical cholinergic function
22. Left: Coronal T1-weighted MRI of a 74-year-old man with moderate Alzheimer-type
dementia. Diffuse cerebral and hippocampal atrophy with ex vacuo ventricular and cortical
sulcal dilation is noted.
Right: Coronal T1-weighted MRI of a 70-year-old woman with behavioral variant
frontotemporal lobar dementia. Atrophy of the right greater than the left temporal lobes is
out of proportion to atrophy of the frontal and parietal lobes.
24. Treatment
cerebral vasodilators, stimulants, l-dopa, massive doses of vitamins B, C, and
E, gingko biloba, hyperbaric oxygen, intravenous immunoglobulin, oral
physostigmine, choline, and lecithin- DON'T WORK!
25. • Cholinesterase inhibitors
Patients with AD have reduced cerebral content of choline acetyltransferase,
which leads to a decrease in acetylcholine synthesis and impaired cortical
cholinergic function
(donepezil, rivastigmine, and galantamine) increase cholinergic transmission
by inhibiting cholinesterase at the synaptic cleft
trial of a cholinesterase inhibitor for symptomatic treatment of cognition and
global functioning
Modest benefit
No neuroprotective role
Do not alter disease activity
26. N-methyl-D-aspartate (NMDA) receptor antagonist
proposed to be neuroprotective
Excessive NMDA stimulation by glutamate leads to excitotoxicity
Agents that block pathologic stimulation of NMDA receptors -->
protect against further damage
Moderate to severe Dementia
Less side effects
Memantine is initiated 5 mg once daily; the dose can be increased by
5 mg weekly to a maximum tolerated dose of 20 mg per day, usually in
two divided doses
27. Monoclonal Antibodies
ADUCANUMAB- recombinant monoclonal antibody directed against amyloid
beta
reducing amyloid beta plaques in the brain
Used in mild CI or dementia
Documented amyloid pathology
28. Vitamin E
1000 international units twice daily
mild to moderate AD
delays functional progression
Anti-oxidant effects