Dementia Flashcards
What is dementia?
An acquired, progressive impairment of cognition without clouding of consciousness that has been present for at least 6 months
The impairment needs to be present in at least 2 cognitive domains
What are the cognitive domains?
Language Movement Behaviour Memory Visuospatial Executive function
What are the features of cognitive decline?
Memory loss Reduced attention and concentration Slow and muddled thinking Loss of insight into actions Disorientation in space and time Muddled speech and difficulty understanding what is being said Repetitive purposeless movements Restlessness and wondering Odd and disorganised behaviour
What are primary degenerative conditions that cause dementia?
Alzheimer’s disease
Lewy body
Picks disease
What are secondary causes of dementia?
Vascular dementia
Depression
Infective (HIV, syphilis, encephalitis, CJD (mad cow))
Neurological (huntington’s parkinson’s, motor neurone disease, intracranial tumour)
Alcohol abuse
Head injury
What is the most common cause of dementia?
Alzheimer’s disease
What are the genetic changes in Alzheimer’s disease?
Polymorphisms in the ApoE gene
What are the macroscopic changes in Alzheimer’s disease?
Cortical atrophy with thinning of sulci and gyri, with the occipital lobe being spared
Compensatory ventricular enlargement
What are the histological changes in Alzheimer’s disease?
Extra cellular and peri-vascular deposition of B-amyloid plaques
What are the neurotransmitter changes in Alzheimer’s disease?
Reduced acetylcholine in the nucleus basalis of Meynert
What age does Alzheimer’s disease typically present?
Over 60s
What are the symptoms of Alzheimer’s disease?
Progressive memory loss
Disorientation - especially somewhere new
Speech - trouble getting words out and understanding speech
Behaviour - wondering, restless, agitation, frustration, aggressive outbursts
What is vascular dementia?
Cognitive decline as a consequence of multiple small vessels infarcts within the brain
What is the pattern of onset of vascular dementia?
Sudden onset with stepwise progression of symptoms
symptoms develop, plateau, suddenly get worse then plateau again
What symptoms are seen in vascular dementia?
Functional deficits - gait disturbance, urinary incontinence
Mood and personality disturbance, mood disorders
Memory loss
Preservation of insight
How is vascular dementia diagnosed?
Clinical assessment
SPECT scan shows reduced attenuation throughout the brain
What is lewy body dementia?
Cognitive decline caused by levy body deposition in the substantia nigra
What are the characteristic clinical features in lewy body dementia?
Fluctuating cognitions with lucid periods and recurrent visual hallucinations
What are the symptoms of lewy body dementia?
Difficulty with executive function (multi-tasking and complex tasks) Parkinsonism Psychosis REM sleep disorders Memory loss in late disease
What worsens the symptoms of lewy body dementia?
Typical antipsychotics
What is the difference between the clinical features of Parkinson’s and lewy body dementia?
Time of onset of cognitive decline:
Parkinson’s - cognitive decline at least a year after the onset of parkinsonism
Lewy body - cognitive decline before or at the same time as onset of parkinsonism
How is lewy body dementia diagnosed?
SPECT scan shows low dopamine uptake in the basal ganglia
What is frontotemporal dementia?
Dementia causing behavioural and speech problems that affects the frontal and temporal lobes
What is the age of onset of frontotemporal dementia?
Younger - <70
What is a specific examples of frontotemporal dementia?
Pick’s disease
What is the pathophysiology of Pick’s disease?
Picks cells - swollen neurones
Pick bodies - intracytoplasmic filamentous inclusions
What is the presentation of frontotemporal dementia?
Change in behaviour and personality - decline in interpersonal skills
Apraxia - progressive decline in understanding of words and ability to produce speech
Insight is lost relatively quickly but memory is preserved
What is the presentation of dementia in Huntington’s disease?
Emotional disturbance
Cognitive decline
Motor disturbance - clumsiness, chorieform movements
What is normal pressure hydrocephalus?
A potentially reversible cause of dementia seen in those aged 50-70
What are causes of normal pressure hydrocephalus?
Subarachnoid haemorrhage
Trauma
Idiopathic
What is the presentation of normal pressure hydrocephalus?
Ataxia
Urinary incontinence
Reduced cognitive function
How is normal pressure hydrocephalus diagnosed?
CT - hydrocephalus seen
Lumbar puncture would show normal opening pressures
What is the management of normal pressure hydrocephalus?
VP shunt
What are the cognitive assessment tools - and when should they be used?
Mini mental state exam - to guide whether a pt needs more assessment
MOCA and ACE III - both for more in depth assessment
What is the non-pharmacological management of dementia?
Support groups
Address concerns of the individual
Reassurance
Measures to maximise QoL - care services, OT assessment, community alarm
What are the options for pharmacological management of dementia?
Cholinesterase inhibitors
NMDA antagonist
Non-specifics: antidepressants, anticonvulsants, benzodiazepines - for associated depression or behavioural disturbance
What are examples of cholinesterase inhibitors?
Rivastigmine
Donepezil
Galantamine
How do cholinesterase inhibitors work?
Inhibit acetyl cholinesterase - this increases the amount of ACh in the synapse
Not a treatment but can slow cognitive decline and improve behaviour
In which conditions are cholinesterase inhibitors most effective?
Alzheimers disease
Also used in lewy body dementia
What are the side effects of cholinesterase inhibitors?
GI upset Hyper-salivation Vivid dreams Sleeplessness Urinary incontinence
What is an example of NMDA antagonists?
Memantine
What conditions can NMDA antagonists be used in?
Severe Alzheimer’s
Second line to cholinesterase inhibitors
What are side effects of NMDA antagonists?
Drowsiness
Dizziness
Constipation
Balance disorders
What is delirium?
Impaired consciousness with intrusive abnormalities of perception and affect of acute onset and fluctuating course
What are the clinical features of delirium?
Impairment of consciousness Disturbance of cognition Psychomotor disturbance Disturbance of sleep-wake cycle Emotional disturbance
What are some drugs that can cause delirium?
Anticholinergics Anticonvulsants Anti-parkinsonism drugs Steroids Opiates Sedatives
What are risk factors for delirium?
Increasing age Dementia or other cognitive deficit Previous episode of delirium Peri-operative Existing sensory deficits Immobility Social isolation New environment Stress
What is the management of delirium?
Identify and treat cause
Corroborative history
Manage environment, provide support
Pharmacological - haloperidol, lorazepam (start low and go slow)
What is the prognosis of delirium?
Mean duration 1-4 weeks
Minority can become chronic
