Alzheimer's Disease

Question 1

Pathophysiology of AD?

Answer 1

• APO3 e4 risk factor for late onset. increases risk
• amyloid precursor protein forms, enzymes break into small chunks, it clumps together to form a plaque
• neurofibrillary tangles
• distributes through the tissues, producing small lesions within the tissue.

Question 2

Which areas of brain are first affected by AD

Answer 2

temporal regions - mesial temporal atrophy

then moves to posterior regions, causing a disconnection between frontal and posterior regions

Question 3

where are there no tangles and plaques found in AD

Answer 3

area 17 - vision

corpus callosum, auditory, sensory and motor areas.

AD is a secondary and tertiary area disease

Question 4

Amyloid or tau occurs closer to diagnosis

Answer 4

amyloid can occur up to 20 years prior to diagnosis, but tau occurs much closer to diagnosis and may be a better diagnostic factor

tau aggregation, which interferes with neuronal integrity and possibly drives neurodegeneration and cognitive decline.

Question 5

How can we image AD pathology

Answer 5

PiB-PET - marks amyloid

Question 6

What is the greatest risk factor for AD?

Answer 6

age.

> 65

majority are 75-85

next us 85 and up

Question 7

What is the greatest risk factor for AD?

Answer 7

age.

> 65

majority are 75-85

next us 85 and up

Question 8

What is APOE E4

Answer 8

• 20% of cases of Late Onset AD related with APOE4
• APOE alleles are on chromosome 19
• APOE4 alleles play a role in Cholesterol transportation
• 1 copy of APOE4 increases the risk of acquiring AD 3 times
• 2 copies of APOE4 increases the risk 5 times

Question 9

What are some identified autosomal dominant AD genes

Answer 9

• 3 genes identified with Autosomal Dominant mutation (2% of
cases of AD) with abnormal production of amyloid ß
• #1 Presenilin 1, mutation on chromosome 14.
• #2APP mutation (Amyloid Precurson Protein), chromosome 21.
• #3Presenilin 2, mutation on chromosome 1.

Question 10

What is the relationship between down’s syndrome and AD

Answer 10

if they survive to midlife, they will get AD.

• Trisomy 21
• 3 copies of APP (Amyloid Precursor Protein)

Question 11

How heritable is AD

Answer 11

79%

Question 12

how much does having one APOE E4 allele increase risk by?

Answer 12

20%

Question 13

What are some environmental risk factors to AD

Answer 13

 Smoking, being single, low social support, and depression related to greater risk of developing Alzheimer’s
 Mediterranean diet, exercise, education, and cognitive engagement predict a lower risk e.g. solving crossword puzzles, reading the newspaper daily
 Cognitive reserve - Use alternative brain networks to compensate for disease

Question 14

what are some neuropsychiatric features of AD when it is a Mild stage NCD

Answer 14

apathy and depression

Question 15

what are some neuropsychiatric features of AD when it is a Moderate stage NCD

Answer 15

psychotic features, irritability, agitation, combativeness, sun downing and wandering

Question 16

how long is it usually from diagnosis to dead in AD

Answer 16

10 yrs

Question 17

how does death usually come about in AD

Answer 17

aspiration pneumonia

Question 18

behavioural symptoms in AD?

Answer 18

hallucinations, delusions, depression, apathy,

agitation, aggression, pacing, wandering, sleep disturbances.

Question 19

What’s the difference between someone with a diagnosis of mild NCD and major NCD?

Answer 19

mild has - decline in learning and memory
major has - decline in memory and in one other domain

both have steady progressive gradual decline in cognition without extended phases
and
no evidence of mixed aetiology