CBL Review – Lewy Body Dementia and Delirium

Katy Davidson and Robyn Dane

DefinitionsDelirium (acute confusional state (ACS)) - : A sudden state of severe confusion and rapid changes in brain function, sometimes associated with hallucinations and hyperactivity . Delirium can occur along side dementia.Essestial features of delirium include:Acute onset (hours/days) and a fluctuating courseInattention or distractionDisorganized thinking or a altered level of consciousness

DementiaDementia is a loss of mental ability severe enough to interfere with normal activities of daily living, lasing more than 6 months, not present since birth, and not associated with a loss or alteration of consciousness.

Dementia of Lewy Bodies (DLB) – second most common type of dementia. Defined by protein deposits, called Lewy bodies, developing in nerve cells in regions of the brain involved in thinking, memory and movement

Alzheimer’s -  a progressive, degenerative disorder that attacks the brain's nerve cells, or neurons, resulting in loss of memory, thinking and language skills, and behavioural changes.

Delirium

Important points

Don’t assume that symptoms of delirium are related to long-term dementia

Still investigate other causes

Patient’s are very vulnerable

Very easy to miss the diagnosis

Risk factors Age >65 years Pre-existing cognitive impairment Previous delirium Drug use Operations Social isolation

DeliriumCauses

• Acute infections• Drugs and toxic substances i.e. alcohol• Surgery• Vascular disease i.e. migraines• Metabolic i.e. renal disease• Vitamin deficiencies• Endocrine i.e. thyroid disorders• Trauma• Epilepsy• Malignancy• Urinary retention

VascularInfections/inflammatoryTraumaAutoimmuneMetabolicIatrogenicNeoplasia

CongenitalDegenerativeEndocrine

TreatmentTreat the underlying cause Non-pharmacologic management Optimize environment using photographs, clock and calendar keeping the room quietPharmacologic managementNeuroleptics may be needed if the patient is having distressing hallucinations/delusions or the patient is very agitatedHigh potency with low anticholinergic activityLow dose Haloperidol or risperdone.

Dementia of Lewy Bodies (DLB)

• 15 – 25% of all dementia – second most common after Alzheimer’s

• Characterised by the build up of Lewy bodies• Alpha-synulcein

• Typically presents in 50-70 year olds

• Typical presentation• Fluctuating symptoms• Visuospatial impairment - visual hallucinations• Parkinsonism• Depression• Sleep disturbance• Possibly transient loss of consciousness• Extrapyramidal symptoms

• Imaging – more use to exclude other diagnoses• Most important feature – hippocampi remain the same size.

This distinguishes from Alzheimer’s

• Management – anticholinesterases e.g. rivastigmine

Alzheimer’s• Amyloid plaques and neurofibrillary tangles• Atrophy of brain tissue

• Frontal and temporal lobes and the hippocampus• Dilation of the ventricles

• Reduced cholinergic transmission• Mean survival 2- 7 years• Management – anticholinesterases

Vascular dementia• Many small infarcts due to cerebrovascular disease• Step-wise progression

• No change for a while and then a sudden drop in functions• May also develop

• Pseudobulbar palsy• Shuffling gait with small steps

• History of TIAs possible• Management – focussed more on prevention (aspirin/warfarin, BP control, possibly

benefit from anticholinesterases)

Parameter Dementia Delerium

Onset Insidious and gradual (months-years)

Rapid (hours-days)

Awareness/Alertness

Clear, generally normal

Reduced and fluctuates

Level of consciousness

Intact Disturbed

Course Slow continuous decline that becomes relatively stable over time

Hours/weeks – quickly resolves after cause removed

Psychotic symptoms Delusions and hallucinations can occur late in dementia

Delusions common

Mr. T is a 70-year-old male admitted to the orthopedic unit . Mr. T fractured his right ankle in a golf outing and had an open reduction with internal fixation this morning. The nurse tells you that Mr. T is insisting on going home and keeps getting out of bed. Multiple attempts to explain that he is unable to walk safely in the cast have not convinced him and he is now yelling, disturbing other patients on the floor.

You suspect that Mr. T’s condition is caused by:a. Post-operative infectionb. Dementiac. Delirium d. Depression

Delirium is caused by:a. Infectionb. Hypoxiac. Medicationsd. All of the above

Some strategies to assist in caring for Mr. T would include:

a.Reality orientation offered in a calm, nonjudgmental manner

b.Calling family to visit the patient c.Telling the patient to relax and his ankle will heald. None of the above

Ms. D is a 98-year-old female in a nursing facility with a diagnosis of Alzheimer’s disease. Ms. D comes to the nursing station and appears very upset. She tells you that she is looking for her mother and asks you to help her. You start walking with Ms. D.

Which of the following would help?

1.Telling her that her mother died a long time ago2.Reassuring her that everything is okay and that you will help her3.Attempting to distract her into a pleasurable activity (eating, singing)4.Using reality orientation hoping to reverse her cognitive losses.5.Asking her to help you with a small task and later you will look for her mother together6.Although pharmacologic agents may be helpful (in the presence of disturbing delusions / hallucinations), behavioural approaches to treatment are the first-line in treating dementia.7.Promoting dependence (with feeding, dressing, toileting) is advantageous for persons with dementia.8.Compensating for sensory impairments (glasses, hearing aides) may help minimize disturbing illusions/ delusions.

What can you remember about memory?

If I can remember how to drive my car but I can’t remember the name of the street I’m going to?

What type of memory have I lost?

Declarative - semantic

What can you remember about memory?If I can tell you the story of how I learned

to ride my bike, but I can no longer remember how to do it.

What type of memory have I lost? Procedural memory (skill learning)

Which subcortical structures are involved in this type?

Cerebellum and basal ganglia

What can you remember about memory?

Knowing the capital of Somalia =

Mogadishu

What is this type of memory?Declarative, semantic

I can understand the conversation but I can’t find the words to reply and have difficulty forming sentences.Which area of the brain has been affected and what is the term for this condition?

Broca’s areaExpressive dysphasia

Dr: What is your name?Pt: My sister’s visiting later

Which area of the brain has been affected and what is the term for this condition?

Wernicke’s areaReceptive dysphasia

Useful links

http://radiopaedia.org/articles/dementia-with-lewy-bodies

http://almostadoctor.co.uk/content/systems/neurology-psychiatry/psychiatry/dementia

http://bestpractice.bmj.com/best-practice/monograph/320/diagnosis/differential.html