Dementia Flashcards
Confusion = … until proven otherwise
Due to acute illness
When Dx dementia, what do you need to ensure?
➤ No treatable cause
What is dementia?
It is a syndrome of many causes of global impairment of cognition without impairment of consciousness.
Key to diagnosis dementia
Good Hx
Types of dementia
- Alzheimer’s disease.
- Vascular dementias (or multi-infarct dementia).
- Lewy body dementias.
- Frontal lobe dementias (such as Pick’s disease).
- Subcortical dementias (such as Huntington or progressive supranuclear palsy).
- Focal cortical atrophy syndromes (such as primary aphasia).
- Metabolic-toxic dementias (such as chronic hypothyroidism or B12 deficiency).
- Infections (such as syphillis, neuroAIDS or chronic meningitis).
Lewy body dementia - Where? Characteristed by? Tx?
o Third commonest type of dementia (15-25%).
o Lewy body in the brainstem (midbrain) and cortex.
o Characterised by fluctuating cognitive loss, alertness. Parkinson manifestation. Visual hallucination.
o Rivastigmine might help (cholinesterase inhibitors).
Common causes of dementia
- Alzheimer’s disease.
- Vascular dementia. 25% (multiple small strokes) or also called (multi-infarct dementia). Evidence of vascular pathology (ex: high BP, stroke, stepwise deterioration)
- Lewy body dementia. Characterised by Lewy body in the brainstem and neo-cortex and fluctuating symptoms but persistent cognitive impairment.
- Frontotemporal dementia. Characterized by atrophy of frontal and temporal lobes. Change in personality, emotional unconcern disinhibition, hyperorality, stereotyped behaviour. No features of Alzheimer’s pathology.
! Ameliorable causes of dementia
- Decrease T4
- Decrease B12/Folate
- Decrease thiamine
- Parkinson’s disease, Syphilis, Pellagra
- Cerebral tumours (ex: meningiomas)
- Subdural haematoma
- Normal pressure hydrocephalus
Rare causes of dementia
- Chronic alcohol or barbiturate abuse.
- Pellagra / Nicotinic acid deficiency.
- CJD.
- Parkinson’s.
- HIV.
- Progressive leukoencephalopathy.
Symptoms of dementia
- Normal daily tasks are done with increasing incompetence.
- Increase forgetfulness (progressive impairment of memory and other cognitive functioning).
- Personality changes.
Dementia - Tests / Ix
- FBC/ film, U&E, Ca, LFT, TSH, CXR.
- Urine test.
- Syphilis serology.
- Folate/ B12.
- CT.
- EEG & CSF examination.
- HIV test.
Dementia - Management
- Deal with treatable conditions.
- Social services.
- Carer support.
- In most people dementia will remains and progress.
Dementia - Living with dementia / Ideas
- Support for carers & family members
- Dx
- Practical help
- Local support & services
- Legal planning & dementia
- Money matters
- Getting a break
Dementia - Younger people with dementia / ideas
- Local support
- Support online
- Children & family
- Future care options
- Maintaining skills
- Benefits available
- Employment
- Fact sheets
Alzheimer’s disease - onset?
- Now includes onset at any age. Onset may be from 40 years old.
- Prevalence: 10% over age 65, 47% over age 84.
Most common cause of dementia in the elderly
Alzeihmer’s disease
Alzheimer’s disease - Survival?
Survival: 7yr from onset.
Alzheimer’s disease - Characteristics
The patient will remember things that happened many years ago very clearly, but events in the recent past are forgotten.
Alzheimer’s disease - Pathophysiology
- Two microscopic changes occur in the brain in Alzheimer’s disease: Senile plaques develop between neurons, while neurofibrillary tangles develop within neurons.
- These changes are thought to be related to the cause, development, and course of the disease.
- Involvement of cholinergic neurons causes levels of acetylcholine within synapses to decline.
- Levels of acetylcholine esterase also drop, perhaps to compensate for the loss of acetylcholine.
- Activity of another cholinesterase enzyme increases, and a significant portion of acetylcholine is metabolized by this enzyme as the disease progresses.
- Eventually the neuron is destroyed
Alzheimer’s disease - Risk factors
o Defective genes on chromosomes 1, 14, 19 and 21.
o Family history of Alzheimer’s disease.
o Aging and oestrogen deficiency.
o Head injury.
Alzheimer’s disease - Presentation
o There is no natural standard history, cognitive impairment is progressive but behavioural and psychotic symptoms may disappear at later course of disease.
o Behavioural changes: aggression, wandering.
o Lack of concentration.
o Confusion about time & place (loss of visual-spatial skill).
o Anosognosia (lack of awareness): disinhibition.
o Sometimes saying or doing outrageous things
o Mood can be depressed, anxious or agitated.
o Reasoning can become slow and muddled.
o Some people may experience hallucinations or delusion.
o Parkinsonism, wasting, incontinence and seizures may occur.
Alzheimer’s disease - Dx
o Early diagnosis may help patients to take legal decisions.
o Brain imaging and neuropsychological tests help rule out fronto-temporal, Lewy body and vascular dementias.
o Need thorough physical exam and complete medical history.
o A careful review of the patient’s medicine, and alcohol use is important.
o Medical conditions, including tumours, infection, and dementia caused by mild strokes (multi-infarct dementia) should be excluded. These possibilities must be ruled out as well through appropriate blood and urine tests, brain MRI or CT and EEGs.
o One of the most important parts of the diagnostic process is to evaluate and exclude the patient from depression and delirium.
o The neurological exam is normal in most patients in early stages.
Alzheimer’s disease - Management
- Social services, family and Alzheimer society.
- Exclude treatable causes.
- Meticulus control of blood pressure, only 5% of dementia is in pure form, 95% is mixed of AD and vascular component. optimal cerebral perfusion is needed, diastolic should not lowered more than 70 mm.
- Treat concurrent illnesses.
- Avoid drugs that suppress cognition (neuroleptics, sedative, tricyclic).
- Arrange a well-lit cognitively stimulating care setting (eg: multisensory stimulation, massage, music & aromatherapy). Also structured conversation and exercise can help.
- Drugs:
Oral cholinestrase inhibitors: help embedding new memories more than accessing the old ones. (Eg: Donepezil 4 mg at night doubled after 4 weeks. Other drugs are rivastigmine and galantamine.)
Antiglutamatergic drugs (Eg: Memantine helps moderate to severe cases of AD (SE, hallucination, confusion, hypertonia, hypersexuality)).
