Dementia
last authored: Jan 2009, David LaPierre
last reviewed:
Introduction
Dementia is a decline in cognition and function. It is a devestating disease with a high burden of symptoms. It is greatly underrepresented in the patient population receiving formal palliative care supports. It might be called brain failure. Memory is one aspect of the brain, but everything that has to do with the brain can fail.
A diagnosis can be helpful for both patient and family, explaining changing behaviours. It is helpful with ensuring safety (driving, stoves, wandering, meds) and ensuring future care.
Lastly, medications can help slow or even reverse progression for some causes.
Dementia is characterized by the gradual and continuous development of multiple cognitive deficits. These symptoms need to be significant enough to affect social or occupational functioning.
Diagnosis of dementia requires:
Memory impairment: impaired ability to code new information or recall previously learned information
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Deficits in another cognitive demain: |
Functional impairment
Acquired and progressive
No other diagnosis.
Dementia is common and prevalence increases with age - 10% of people over 65 and 25% of people over 85 have dementia.
The Case of Mr Thomas
Mr Thomas is a 67 year-old man who is admitted to hospital after falling and fracturing his hip. During his post-operative recovery, his clinical clerk notices Mr Thomas is having some difficulty remembering answers her questions and wonders why.
question: what could be causing Mr. Thomas' memory impairments?
question: how should she go about investigating a possible diagnosis of dementia?
Types of Dementia
Over 50% of cases of dementia are caused by Alzheimer's Disease, and vascular causes account for 15%. The remaining are caused by a number of various diagnoses.
- Alzheimer's
disease - vascular
dementia - Lewy-body
dementia - frontotemporal lobar
degeneration - mixed
dementia - basilar
dementia - Pick's
disease
Alzheimer's Disease
Alzhemier Disease (AD) is the most common dementia in the elderly.
- usually first begins with impairment of higher intellectual functions, such as mood and behaviour
- progressive disorientation, memory loss, and aphasia usually follow
- within 5-10 years patients are profoundly disabled, mute, and immobile
- affects memory (amygdala and hippocampal formation
- language - reading, writing, speaking, but not repetition
- visuospatial function -
- executive function - judgment
Vascular Dementia
Inschemic damage in most cases - mini-strokes
Step-wise loss can happen, but less common than small vessel disease with slow declines.
Variable progression, with fluctuation.
patchy, with issues with attention and cueing. Language and visuospatial.
cueing
Bradyphrenia.
hallucinations, delusions
peculiar gait
incontinence
history of vascular risk factors
focal neurological signs and symptoms
Lewy-Body Dementia
Lewy-body dementia, or Parkinson's disease dementia, is dementia with unique qualities. These include:
- parkinsonism
- fluctuations of symptoms and consciousness
- falls
- hallucinations
- neuroleptic sensitivity, leading to marked rigidity (avoid antipsychotics)
- postural hypotension
- REM sleep disturbance
Frontotemporal Lobar Degeneration
A dementia with prominent change in personality and/or language functions
frontotemporal dementia - disorder of social conduct
primary progressive aphasia - language disturbance
semantic dementia - loss of memory for meaning of words
Mixed Dementia
Common, notably AD plus vascular dementia.
Basilar Dementia
Pick's Disease
Pathophysiology
Memory is not all that is affected; language expression and comprehension, visuospatial skills, decreased attention and concentration, apraxia, apathy, hallucinations, and delusions are all possible.
Executive functions affected by dementia include sequencing, organizing, abstracting, and planning (SOAP).
Dementia is increased in prevalence in people with Down Syndrome and head trauma. Dementia can be cortical or subcortical.
Alzheimer's disease is characterized by a loss of cholinergic neurons from the basal forebrain. This can be evidenced by substantial loss of acetylcholine transferase and acetylcholine esterase, mainly in the temporal cortex. Amyloid plaques and neurofibrillary tangles form. From 90-95% of cases of AD are sporadic, with involvement of ApoE4 (Ch 19). Mutations have been identified in amyloid precursor protein (Ch 21), presenilin 1 (Ch 14), and presenilin 2 (Ch 1).
Lewy Body Dementia
Lewy Body dementia is also characterized by a loss of cholinerigic neurons. Intracytoplasmic inclusion bodies can be seen in these neurons (Lewy Bodies), and alpha-synuclein involved somehow.
Frontotemporal Lobar Degeneration
Frontotemporal lobar degeneration has a number of causes and cellular processes that occur. These include apoptosis, necrosis, genetic, neurotoxicity (free radicals, excitotoxicity), and idiopathic.
- neuronal loss
- spongiosis
- gliosis
- Pick bodies
- ballooned neurons
- Tau-positive inclusions in some; involved in neurofibrillary
- Ubiquitin-positive
- Progranulin-positive
- genetics potentially related to ch 17
Signs and Symptoms
Dementia is a heterogenous disease.
Behaviours vary with stages of dementia, but are often most problematic at later stages. These can be viewed as physical vs verbal, aggressive vs non-aggressive.
- history
- physical exam
- cognitive testing
- staging of AD
History
Dementia requires changing interactions; collateral history becomes indespensible. Family needs to be involved in decisions regarding tests, drugs, or surgeries.
Identifying Information:
- age
- here with:
- lives with:
- supports:
Caregiver history
- onset of cognitive difficulties (usually gradual)
- memory impairment (events, appointments, names)
- repetitive questions, head-turning sign (always looking to collateral for input)
- language: word-finding difficulties
- personality change: irritability, apathy, depression, aggression, disinhibition (social skills are usually preserved early)
IADLs
As for other aspects, get collateral and details. Ask if they ever performed these tasks (ie men who don't cook, women who don't deal with finances), and ask if someone helps now, when did it start, and why?
Finances: money management (cheques, bank, ATM) missed bills, or overpayment; help required; appropriate payment at store or restaurant
Cooking: changes in cooking, baking; forgetfulness; cooking for crowds
Shopping: Planning for groceries, redundant groceries, prompting required, independent shopping
Medications: Missed medications; dossette (who fills it?) call pharmacy
Driving: Would you let your daughter drive with him? accidents; tailgating, driving too slowly; trouble with turns, merging; getting lost
Telephone: Still make calls; call the wrong person; remember numbers; pass on messages
Household chores
Other: TV remote, hobbies
ADLs
Repetitive dressing
Bathing: prompting, help
Toileting
Eating
Other symptoms
- hallucinations
- gait impairment
- urinary incontinence
Past medical history
- hypertension
- ischemic heart disease
- malignancy (brain metastases)
- stroke
- vascular risk factors
- EtOH
- Parkinson's Disease, multiple sclerosis
Some collateral sources are hesitant to 'tattle' on the patient, and it can be helpful to speak with them alone. A question to hone in on their opinion is "would you let your children drive with 'John'?
The most important aspect of these tests is to get patients talking about things that will help you determine diagnosis.
It is important to recognize typical Alzheimer disease and thereby atypical presentations.
Physical Exam
Assess general health and appearance. A full physical exam, especially neurological and cardiovascular, are warranted.
Findings in Alzheimer's disease include:
- clothing (watch dress, undress)
- hygiene
- paratonia
- gait disturbance
Atypical findings
- EPS: Parkinson's, Lewy Body dementia
- neurological findings: normal with AD; localizing signs suggestive of vascular dementia, stroke, or malignancy
- orthostatic hypotension
Cognitive Testing
test |
pros |
cons |
common, easy, many cognitive domains |
affected +/- by education, doesn't test executive functions |
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MOCA (Montreal Cognitive Assessment) |
more difficult, tests executive functions |
|
clock (10 past 11) |
frontal lobe functions (planning) |
many disputed ways of scoring |
Frontal Assessment Battery (12/18 cutoff) |
frontal lobe functions |
|
verbal fluency (F words in one minute; four-legged animals)
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frontal lobe functions |
|
brief cognitive rating scale (BCRS) |
11 axes for cognitive domains, seven stages |
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BCRS
CURE
Current events: news, TV shows (plot, characters, etc) evening meal, children's spouses and grandchildren
US president/ prome minister
relatives: children and spouse
everything: knows name only
Stages of Dementia
Each stage tends to last two years, but there is significant variability.
The brief cognitive rating scale (BCRS) has five axes and is rated against seven stages.
Stage |
Signs and Symptoms |
1 |
normal |
2 |
|
3 |
questionable; isolated memory ir memory plus other deficits |
4 |
mild |
5 |
moderate |
6 |
severe |
7 |
very severe |
8 |
BCRS Axis 2 pnemonic: CURE
4: Current events, television shows, evening meal, recent events
5: US president, prime minister
6: Relatives
7: Everything
BCRS Axis 5 pnemonic: IRAN
mild: IADLs
moderate: Repetitive dressing
severe: ADLs
very severe: Non-ambulatory,non-verbal
The Functional Assessment Staging (FAST) is related to Axis 5 of the BCRS.
1. No difficulties
2. Forgets location of objects; subjective work difficulties
3. Decreased job functioning
4. Decreased ability to perform complex tasks
5. Assistance in choosing proper clothing
6. Difficulty with cloting, bathing, toileting, incontinence
7. Difficulty speaking, ambulating, sitting, smiling, holding head up
Investigations
- lab investigations
- diagnostic imaging
Lab Investigations
Blood tests that should be done to rule out other causes include:
- CBC
- electrolytes
- TSH
- BUN, creatinine
- liver function tests
- glucose
- B12, folate
- calcium, albumin
Diagnostic Imaging
While many physicians will order head imaging on everyone as a course of cognitive workup, particular indications for CT include:
- age below 60
- rapid onset or change
- early gait abnormality
- early incontinence
- focual neurological findings
- hx malignancy
- head injury
- anticoagulant use
- new onset of severe headache/seizure
Differential Diagnosis
Dementia, which is progressive and usually irreversible, should be distinguished from:
- depression tends to be progressive (days to weeks) and episodic
- delirium: more abrupt onset with a fluctuating course
- drugs: onset with additions or adjustments of medications
You should also rule out
- aphasia
- hearing loss
Other causes of cognitive decline can also include:
- Wernicke-Korsakoff (B12/folate deficiency) - pure amnesic syndromes
- medical conditions, ie hypothyroidism
- neurological disease (ie stroke, Huntington's)
Management
Supports
Caregivers should be involved to assist with adherence to medications, appointments, and tests.
Educate about disease stage and prognosis.
Provide awareness of delirium and the need for medical attention if it occurs
Support Groups (ie Alzheimer's Society)
home safety (stoves, food, medication, wandering, knives, water temperature)
future care
adult protection, if necessary
Legal Issues
During early days, ensure:
- enduring power of attorney, will, advance directives, long term care plan
Driving is not absolutely contraindicated with a diagnosis of dementia. Frequent re-assessment is required. A helpful question can be to ask a member of their family "would you feel comfortable letting your child drive with 'John'?"
Education
Provide orientation cues, ie clock, calendar
Medications
Cholinesterase inhibitors (ie donepezil, rivastigmine, galantamine) is useful for mild to moderate AD and Lewy Body dementia, particularly during early stages. They are not cures, though can slow progression of cognitive decline and decrease caregiver burden and apathy. Commonest side effects are GI (nausea), cardiac (bradycardia), respiratory (exacerbating CPOD, asthma), nightmares, irritability.
Mematine (NMDA) receptor agonist blocks excitatory glutamate. Used in late moderate to severe dementia. Renally dosed.
Low dose neuroleptics (ie haloperidol, risperidone) or antidepressants can also be used as appropriate. AVOID NEUROLEPTICS for Lewy Body dementia due to increased sensitivity.
Trazodone can be used for insomnia, agitation, aggression, anxiety
Benzodiazepines should be avoided, as the cause cognitive impairment, falls, fractures, and dependence
Foll
ow-up for adverse effects and efficacy
NSAIDs, estrogen?
Other Conditions
Treat medical problems and prevent others.
It can be challenging to decide on investigating and treating conditions and diseases, such as pneumonia, dissecting aneurysm, dialysis, or anemia, weight loss.
Some symptoms can be difficult to identify in advanced dementia.
Addressing Challenging Behaviours
Define behaviour and whether it is stage-congruent. Apathy and irritability are common in the early stages, while aggressive behaviour and delusions and hallucinations are more common later.
Consider atypical disease presentation.
Non-pharmacological approaches include: being calm, reducing distractions, ensuring glasses and hearing aids, structured routine, simplification, redirect instead of argue, and help them function to their maximum capacity.
ggressive behaviour
Consider delirium, polypharmacy, urinary retention, constipation, overwhelming environment, stimuli, or tasks.
Bathing: consider decreasing frequency, and get patient to help.
Eating: Abdominal pain, constipation? Give one food at a time. food in cups (ie soup, milkshake). Accept decreased oral intake as disease progresses.
Incontinence: UTI, constipation, caffeine
Toilet regularly; watch for pacing. Put a sign on the door as a cue for toilet location.
Dressing: reduce options, and simplify
Sleep: consider causes of insomnia
- adjust room temperature and lighting
- reduce daytime naps
- ensure daytime exercise
Wandering/pacing: drug effect? looking for bathroom? over or under stimulation, enough regular exercise
- provide secure area to wander
- take coat and hat away from front door
- child safety knob covers
- lock near floor
- distract to another activity
- provide finger foods
yelling
- pain, cold, constipated
- restrained?
- hearing aids and glasses
- increase stimulation
- provide positive reinforcement when not yelling
Consequences and Course
Alzheimer's disease is progressive and incurable. The average duration of illness, from onset of symptoms to death, is 8-10 years.
However, up to 10% of cases of dementia, mostly those with vascular causes, are potentially curable.
Dementia is the greatest risk of developing post-operative delirium, requiring care when choosing elective surgery.
The Case of...
Additional Resources
Hogan DB et al. 2008. Diagnosis and treatment of dementia: Approach to management of mild to moderate dementia. CMAJ. 179:787-93.
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