Dementia

Question 1

How is Alzheimer’s diagnosis defined? What are the main features?

Answer 1

• Objective (MMSE etc.) memory defect AND another cognitive deficit e.g. aphasia (word-finding difficulties, agrammatism, phonemic and semantic paraphasias, neologisms), agnosia, apraxia, executive dysfunction
• These deficits result in ADL impairment
• Gradual onset and progressive, continuing decline
• From a previous higher level of function
• Features
  
  • Multiple cognitive deficits
  • Gradual onset, functional impairment, continuous decline​
  • Executive function disturbance
  • Normal gait and posture

Question 2

Describe the course of Alzheimer’s disease. What is the average life-expectancy?

Answer 2

• Memory > executive dysfunction > language, behaviour, personality impairment
• 12-15 year average life-expectancy

Question 3

Which areas of the brain are predominantly affected in Alzheimer’s disease?

Answer 3

• Hippocampal neurons, then neocortical ones

Question 4

What defines vascular dementia?

Answer 4

• Cognitive decline from higher previous level - memory impairment + one other cognitive domain
• CV disease defined by focal abnormalities on neuro exam AND imaging (CT/MRI)
• Inferred relationship between the first two (onset following recognised stroke, abrupt deterioration, fluctuating, stepwise progression)

Question 5

What are the clinical features of vascular dementia?

Answer 5

• Early gait disturbance
• Hx of unsteadiness, frequent and unprovoked falls
• Early urinary symptoms
• Pseudobulbar palsy (diffuse UMN lesion - speech and swallowing difficulties)
• Personality/mood changes (lability, abulia)

Question 6

How is Lewy-body dementia defined?

Answer 6

• Progressive, ADL-interfering cognitive decline
• 2 of: fluctuating cognition with pronounced variations, recurrent detailed visual hallucinations, spontaneous Parkinsonian features (LBs in the brainstem)
• Supportive - repeated falls, syncope, neuroleptic sensitivity, systematised delusions (infidelity, abandonment), hallucinations

Question 7

What medications should be used which particular care in patients with Lewy body dementia?

Answer 7

• Antipsychotics - people with LBD are typically very sensitive to them

Question 8

What are the common clinical features of fronto-temporal dementia?

Answer 8

• Early loss of personality and social awareness
• Speech and language disturbance
• Younger onset
• Disinhibition often prominent (frontal)
• Depression and anxiety common
• Progressive and semantic aphasia
• Mental rigidity/inflexibility

Question 9

What are the cardianl features of normal-pressure hydrocephalus? What is the treatment?

Answer 9

• Ataxia (magnetic gait), cognitive disturbance, urinary incontinence
• Easily treated - CSF shunt (ventriculo-peritoneal)

Question 10

What are some baseline tests you might consider or order in a person thought to have dementia?

Answer 10

• FBE, UEC, TSH, B12, folic acid, BGL, ESR
• CT/MRI

Question 11

What are the broad managmenet principles for someone with dementia?

Answer 11

• Early diagnosis
• Rule out other causes
• Plan for future before cognitive impairment
  
  • Advance care directive, POAs
  • Relocation to a new house if required
• Easier access to healthcare services and support groups
  
  • Memory clinic referral
  • Care for the carer
• Lifestyle changes that may improve overall QOL
• Early drug treatments that may improve QOL and change course of disease

Question 12

What are some pharmacological treatments for Alzheimer’s disease?

Answer 12

• ACh inhibitors - donepezil, rivastigmine, galantamine
• Anti-glutamate - memantine (late stage disease)
• Folic acid and vitamin B
• Consider antipsychotics (low-dose for agitation) and antidepressants

Question 13

What pharmacological treatments are available for Lewy-body dementia? Frontotemporal dementia?

Answer 13

• LB dementia
  
  • ACh inhibitors
• FTD
  
  • SSRI
  • Atypical antipsychotic