This site is 100% ad supported. Please add an exception to adblock for this site.

Alzheimer's Disease


undefined, object
copy deck
Healthy young-old and old-old persons showed significant difference on the mini-mental exam.
False: healthy individuals in these groups scored similarly on the exam.
Name two variables that may confound an older person's score on a mini mental status exam.
1.Testing under timed conditions does result in lower scores
2.Cognitive skills may flucuate by time of day or other variables
3.Deafness (presbyacusis) may interfere with ability to answer questions
Do cognitive skills all decline at a uniform rate, or are some skills preserved longer than others?
Different skills decline at different rates - e.g. language skills are often preserved the longest.
What is a general definition for dementia?
Multiple cognitive deficits that significantly disrupt function.
What are three aspects of memory loss?
3.Executive function
Does incidence of AD vary by gender?
Yes, women are more vulnerable than men.
Which appears more frequently - sporadic or familial AD? How is age of onset related to each type?
Sporadic AD accounts for 80-90% of all cases and has a later age of onset. Familial accounts for 10-20% and has an earlier age of onset.
What is a significant difference in normal age-related atrophy of the brain and atrophy caused by AD?
Normal atrophy is global and uniform, whereas atrophy caused by AD tends to be regional - often with sparing of the pre- and postcentral gyri.
Besides AD and age-related changes, what conditions should be on the differential of dementia in an older patient?
*drug-induced dementia
*vitamin B-12 deficiency
AD is often diagnosed on autopsy or with a brain biopsy, but what non-invasive technique might be used to detect it?
MRI or PET can sometimes be used to detect the presence of characteristic plaques and atrophy.
What is the microscopic criteria for diagnosis of AD? Where in the brain are these histological changes seen?
Amyloid plaques and neurofibrillary tangles seen in the cerebral cortex and limbic system.
What is a mild cognitive impairment? How is it prognostic for AD?
Profound loss in recent memory with preservation of other cognitive skills and daily functioning; presence confers a 10-fold increase in likelihood of AD.
What is the first area of the brain afffected in AD and what symptoms are seen as a result?
The amygdala and hippocampus are affected first and this is manifested as a decline in short-term memory.
What is the medial survival time for patients with AD?
8.5 years
A vegetative state and loss of general function indicates which area of the brain has been affected in AD?
Primary motor and somatosensory cortices.
The early appearance of what symptom is a particularly bad prognostic sign for AD?
Loss of motor skills early in the disease progression.
Amyloid plaques exert a cytotoxic effect on neurons by choking off the blood supply.
False: they plaques are not neurotoxic on their own but they do induce inflammmation that is damaging to neurons.
How are amyloid plaques formed?
Abnormal cleavage of the amyloid precursor protein (APP) results in the formation of the insoluble A-B fragment which subsequently forms aggregates.
What role have A-B fragments been proposed to play in the brains of normal individuals?
It is present in small amounts and thought to play a role in the inhibition of excitatory signals to NMDA receptors.
What genetic information has been used to explain (in part) the relationship between Down's syndrome and a higher incidence and earlier onset of AD?
APP genes are located on chromosome 21, thus are overexpressed in Down's syndrome (trisomy 21). Overexpression of APP in mice has lead to increased plaque formation.
What genetic mutations have been implicated in nearly half of the cases of familial AD?
Mutations in presenilin 1 and 2 on chromosome 1.
Describe how isoforms of Apolipoprotein E are associated with AD.
*E2 and E3 isoforms seem to be protective against AD
*E4 heterozygotes have a 3-4-fold increased risk for AD
*E4 homozygotes have a 7-fold increased risk for AD
Besides anticholinesterases and NMDA antagonists, what are two classes of drugs that have shown promise in the treatment of AD?
*COX-2 inhibitors (reduce inflammatory damage caused by plaques)
*statin drugs
What is the main structural feature of neurofibrillary tangles?
Protein tau in abnormal paired helical arrangements.

Deck Info