Dementia and Memory Loss

Question 1

Alzheimer disease pathologic hallmarks

Answer 1

• Neuritic amyloid plaques
• Neurofibrillary tangles (νευροινιδιακές αλλοιώσεις)
• Synaptic and neuronal losses (αφορά κυρίως χολινεργικούς, νοραδρενεργικούς και ντοπαμινεργικούς νευρώνες)

Question 2

APOE 4 gene and risk for AD

Answer 2

It is the principal gene involved in risk of onset AD in older individuals
It is not a causative gene but does strongly influence risk, particularly in persons 60–80 years
of age.
The APOE gene, on chromosome 19, occurs in three allelic variants: ε3, which is the most common, and ε2 and ε4, which are less common. Each person has two alleles, and ε4 heterozygosity (presence of one ε4 allele) or homozygosity (presence of two ε4 alleles) increases the risk of AD. The ε2 allele is protective for AD, decreasing risk of developing the disorder.
Although estimates of the risk of an ε4 allele vary and depend on age, presence of one ε4 allele is
associated with about a two- to threefold increase in AD, and presence of two ε4 alleles may increase risk as much as five to 15-fold. However, there are still individuals who are
elderly and have two ε4 alleles who may not develop AD.
In elder Americans, about 33% of those without AD have at least one ε4 allele, and about 67% of those with AD have at least one ε4 allele.

Question 3

Major genes of inherited AD and pattern of inheritance

Answer 3

PSEN1, PSEN2 and APP

autosomal dominant inheritance

Question 4

Age at which AD is considered late onset

Answer 4

65

Question 5

Which is the most common dementia before the age of 60

Answer 5

Frontotemporal Dementia

Question 6

Which is the most striking neuropsychological finding differentiating patient with FTD from AD

Answer 6

Preservation of visuospatial abilities early in the disease