Dementia

Question 1

What differential diagnosis are there for dementia and memory loss?

Answer 1

Metabolic dementia (hypothyroidism, Addison’s)
B12/folate/thiamine deficiency
Syphilis
Brain tumour
Normal pressure hydrocephalus
Subdural haematoma
Depression
Chronic drug use e.g. alcohol, barbiturates
HIV-related cognitive impairment/dementia
Prion protein disease e.g. Creutzfeldt-Jakob disease (CJD)

Question 2

What epidemiology is related to Alzheimer’s?

Answer 2

More common in females

Usually begins age 60

Question 3

What symptoms occur in Alzheimer’s and how does the disease progress?

Answer 3

Memory loss - usually 1st symptom
Cognitive impairment
Impairment in planning, reasoning, speech and orientation

Steady progression

Question 4

What is the pathophysiology of Alzheimer’s?

Answer 4

Amyloid plaques deposits and neurofibrillary tangles lead reduction in transmission of information and death of brain cells

Question 5

Which areas of the brain are atrophied in Alzheimer’s?

Answer 5

Medial temporal lobe (Hippocampus - leads to episodic memory loss)
Inferior temporal lobe (semantic memory)
Lateral temporal lobe (Wernicke's area)
Parietal lobe
Locus coeruleus - 1st affected

Question 6

What epidemiology is related to vascular dementia?

Answer 6

More common in men and stroke patients

Question 7

What symptoms occur in vascular dementia and how does the disease progress?

Answer 7

Functional impairment seen before memory loss
Focal neurological abnormalities e.g. visual disturbances, sensory or motor symptoms
Mood disturbances and mood disorders are common
Difficulty with attention and concentration
Seizures
Memory, gait and speech disturbances

Stepwise progression

Question 8

What are the main subtypes of vascular dementia?

Answer 8

Stroke-related VD = multi-infarct or single-infarct dementia

Subcortical VD = caused by small vessel disease

Mixed dementia = the presence of both VD and Alzheimer’s

Question 9

What epidemiology is related to Lewy body dementia?

Answer 9

Affects men more than women

Mostly >50 years old

Question 10

What symptoms occur in Lewy body dementia and how does the disease progress?

Answer 10

Visual hallucinations, Parkinsonism and fluctuating cognition 
REM sleep disorder
Impaired attention
Impaired executive function 
Impaired visuospatial function

Rapid progression - death common after 7 years

Question 11

What symptoms occur in frontotemporal lobar dementia (Pick’s disease)?

Answer 11

1. Behaviour presentation:
Altered emotional responsiveness
Apathy
Disinhibition
Impulsivity
Child-like behaviours 

2. Semantic presentation:
   Unable to understand words or determine meaning of common words
   Difficulty in name retrieval
   Progresses to inability to recognise objects or faces

3. Non-fluent presentation
Speech apraxia (poor articulation) and not fluent

Question 12

What is dysexecutive syndrome?

Answer 12

Dysfunction in executive functions (e.g. working memory, planning, abstract thinking, mental flexibility and behavioural control) due to brain damage to frontal lobe

Can be caused by brain tumour, stroke, or different types of dementia (Alzheimer’s, VD, frontotemporal)

Can be assessed using frontal assessment battery (FAB) scale

Question 13

What scale is good for differentiating between Alzheimer’s and frontotemporal dementia?

Answer 13

Frontal assessment battery scale:

Score of <=12 highly suggestive of frontotemporal dementia

Question 14

What cognitive function test can be used to assess presence of Alzheimer’s?

Answer 14

ACE III plus 2 episodic memory tests

Can also use MoCA and MMSE

Question 15

What treatment can be given in Alzheimer’s?

Answer 15

Mild-moderate:
Acetylcholinesterase inhibitors (Donepezil, galantamine or rivastigmine)

Severe:
Memantine mono therapy or dual therapy with acetylcholinesterase inhibitor

Question 16

What treatment can be given in non-alzheimer’s dementia?

Answer 16

Mild-moderate Lewy body:
Donepezil, galantamine or rivastigmine

Severe Lewy body:
Donepezil or rivastigmine or memantine

Only give acetylcholinesterase inhibitor to VD patient if they have mixed dementia

Don’t give acetylcholinesterase inhibitor or memantine in frontotemporal dementia

Question 17

What medications can cause worsen parkinsonism and increase risk of NMS if given to Lewy body dementia patients?

Answer 17

Antipsychotics

If psychotic, low dose quetiapine and clozapine are drug of choice

Question 18

What is the pathophysiology of Lewy body dementia?

Answer 18

Lewy bodies (alpha-synuclein) proteins are deposited in the brain leading to neuronal death