NB14-4 & 14-5 - Neurocognitive Disorders and DLA

Question 1

List the domains of cognition

Answer 1

• Memory
• Language
• Executive Functions
• Visuospatial Functioning

Question 2

What are the diagnostic criteria for a neurocognitive disorder?

Answer 2

Decline in at least one cognitive domain occurring after the developmental years.

• Major NCD: significant decline that interferes with independence in activities of daily living (ADLs)
• Mild NCD: modest decline that does NOT interfere with independence in ADLs

Question 3

List the neurocognitive disorders (NCDs) we need to know.

Answer 3

• Delirium
• Amnesia
• Dementia (many subtypes)

Question 4

Answer 4

A

Question 5

What constitutes a delirium and what are the other names for delirium

Answer 5

A delirium (aka - acute confusional state, acute brain syndrome, encephalopathy, ICY syndrome) involves:

1. A disturbance in awareness (one’s orientation to the environment) and attention (one’s ability to direct, focus, sustain, and shift attention)
2. An additional disturbance in a cognitive domain
3. A sudden onset of symptoms (hours to a few days) that typically fluctuate during the day
4. Evidence for a direct physiological cause

Question 6

Describe the general pathology of a delirium

Answer 6

There are multiple possible causes but usually widespread brain regions are affected with the core deficits being in central cholinergic functioning, especially the reticular activating system and its ascending connections.

Question 7

What are the largest risk factor for developing delirium?

Answer 7

Non-modifiable - poor health, older age, male gender

Modifiable - immobilization, poor sleep, use of benzodiazepines in an ICU

Question 8

What is the typical treatment plan for delirium?

Answer 8

• Identify and treat the underlying medical condition
• Utilize environmental supportive measures to provide orienting stimuli, remove disorienting stimuli, and provide for safety needs
• Use antipsychotics to treat associated symptoms
• Use benzodiazepines to treat alcohol withdrawl induced delirium

Question 9

When is a memory deficit not considered to be amnesia?

Answer 9

If the memory deficit occurs within the context of general cognitive decline

Question 10

What is the typical treatment plan for amnesia?

Answer 10

• Identify and treat underlying medical condition
• Cognitive Rehabilitation
  
  • Restoration of Function - memory exercises to strengthen memory through repetition
  • Compensation (tools to help with memory)
    
    • External Strategies (ie - lists and calendars)
    • Internal Strategies (ie - mnemonics)

Question 11

What constitutes a dementia? What is the usual prognosis of a dementia?

Answer 11

Multiple and severe cognitive impairments without the impairment of consciousness.

Prognosis is typically poor because dementias are generally progressive and irreversible.

Question 12

What are the diagnostic criteria for alzheimer’s dementia (AD)?

Answer 12

• Significant memory impairment plus impairment in at least one other cognitive domain
• A gradual onset with steadily progressive decline
• Exclusion of other causes of the symptoms

Question 13

Describe the general course of AD

Answer 13

• Early Stages - memory deficits (rapid forgetting) and anomia (can’t remember names of objects). Typically begins in late 70s
• Middle Stages - further memory decline, language and visuospatial defecits develop, agnosias (inability to recognize things/people/places) develop, mood/personality changes develop, psychosis develops
• Late Stages - global aphasia, motor dysfunction, death from opportunistic infections

Question 14

What neuroanatomical, neurochemical, and neurofunctional changes are often seen in AD patients?

Answer 14

• Neuroanatomical Changes - cortical & hippocampal atrophy, and enlarged ventricles
• Neurochemical Changes - multiple NT deficiencies with particular focus on the loss of cholinergic neurons in the nucleus basalis of Meynert due to its role in memory formation
• Neurofunctional Changes - posterior hypometabolism (parietal/temporal)

Question 15

What is the typical treatment plan for AD?

Answer 15

There are four FDA-approved drugs:

• Three Cholinesterase Inhibitors
  
  • donepezil (aricept)
  • galantamine (razadyne)
  • rivastigmine (exelon)
• One NMDA receptor blocker
  
  • memantine (namenda)

Side effects have notable consequences for elderly and these drugs aren’t very effective.

Question 16

Answer 16

C

Question 17

Answer 17

C

Question 18

List the differential diagnoses for AD?

Answer 18

• Vascular Dementia
• Frontotemporal Degenerative Disease
• Lewy Body Disease
• Parkinson’s Disease
• Huntington’s Disease
• Prion Disease
• Pseudodementia
• Benign Senescent Forgetfulness

Question 19

What causes vascular dementia? How does it typically present and progress? How is it usually treated?

Answer 19

Vascular dementia results from multiple infarcts caused by cerebral vascular disease (CVD). Onset is usually sudden, presenting with focal neurological signs. Headache and seizure are common in the early stages and the disease progresses in a stepwise manner.

Treatment of the underlying CVD is performed to prevent further damage

Question 20

How can you distinguish vascular dementia from AD?

Answer 20

• Vascular dementia patients usually have a history of CVD
• The memory deficits in AD are typically encoding based while in vascular dementia they are typically retrieval based
• Vascular dementia typically presents with a left-right discrepancy in motor functions test while AD does not

Question 21

How can frontotemporal dementia (FTD) be distinguished from AD?

Answer 21

• FTD has an earlier age of onset (40s-50s)
• FTD has frontal lobe atrophy and hypometabolism
• Pick bodies can be seen in histology

Question 22

What are the features of Lewy Body Dementia (LBD)?

Answer 22

• Core Clinical Features
  
  • fluctuating cognition/alertness
  • visual hallucinations
  • mild parkinsonism (but usually no tremors)
• Additional Features
  
  • Lewy bodies in histology
  • REM-sleep behavior disorder often precedes LBD by many years

Question 23

How is LBD typically treated?

Answer 23

• Hallucinations can’t usually be treated by neuroleptics because these patients often have sever sensitivity to them. So hallucinations are just treated with benign neglect
• Parkinson’s drugs are relatively ineffective in LBD and can worsen psychosis so these symptoms are often left untreated

Question 24

What is parkinson’s disease dementia (PDD) and how is it diagnosed?

Answer 24

PDD is a dementia that PD patients can develop. It is very similar to LBD. Use 1-year rule for diagnosing LBD vs PDD:

• If dementia develops >12 months after PD then PDD can be diagnosed
• If dementia develops before or <12 months after PD then LBD is diagnosed

Question 25

How can you distinguish between a prion disease and AD?

Answer 25

A prion disease leads to a very rapidly progressing dementia with death usually occurring in under a year

Question 26

What is a pseudodementia? How do you distinguish it from AD?

Answer 26

Memory and other cognitive disturbances that resemble a dementia occurring in depressed elderly patients

See image for distinguishing from AD

Question 27

What is benign senescent forgetfulness (BSF)?

Answer 27

Cognitive decline associated with normal aging

Question 28

What should be done before any NCD is diagnosed?

Answer 28

The patient should be referred for neuropsychological testing which will comprehensively assess a person’s cognitive functions and help locate dysfunctions in specific brain areas

Question 29

How can it be determined if a persons memory deficits are encoding based or retrieval based?

Answer 29

When a patient is unable to remember something from a memory test, provide them with helpful cues. If the cues help then you know encoding occurred and the problem is retrieval based (prefrontal). If the cues didn’t help then you know encoding didn’t occur and the problem is encoding based (mesial temporal)

Question 30

Answer 30

D

Question 31

Answer 31

F

Question 32

Answer 32

E