Dementia Flashcards
Different Types of Onset Dementia
Young onset dementia - under 65
- Genetic influence
- Onset in 40s and 50s
Late onset - over 65
- Genetic influence is not the biggest risk factor
- 85 years average age of diagnosis
95% of cases - Estimated to be above 1 million in 34 years in Australia
Mild Cognitive Impairment
(Mild Neurocognitive Disorder)
- modest cognitive decline
- no interference in complex activities of daily living
Dementia
(Major Neurocognitive Disorder)
- severe versions of the former
Disease Pathways of Dementia
- Alzheimer’s 60-80%
- Lew body dementia 5-10%
- Vascular
- Frontotemporal
DSM-V Criteria For Mild Neurocognitive Disorder
A. Evidence of modest cognitive decline from a previous level of performance in one or more cognitive domains based on:
- Concern of the individual, a knowledgeable informant, or the clinician that there has been a mild decline in cognitive function; and
- A modest impairment in cognitive performance, preferably documented by standardised neuropsychological testing or, in its absence, another quantified clinical assessment
B. The cognitive deficits do not interfere with capacity for independence in everyday activities
C. The cognitive deficits do not occur exclusively in the context of a delirium
D> The cognitive deficits are not better explained by another mental disorder
DSM-V Criteria for Major Neurocognitive Disorder
A. Evidence of significant cognitive decline from a previous level of performance in one or more cognitive domains based on:
- concern of the individual, a knowledgeable informant, or the clinician that there has been a significant decline in cognitive function
- a substantial impairment in cognitive performance, preferably documented by standardised neuropsychological testing or, in its absence, another quantified clinical assessment
B. The cognitive deficits interfere with independence in everday activities
C. and D. same as Minor
Testing Cognition
Screening Tools
- Mini-mental state exam (MMSE)
- Montreal cognitive assessment (MoCA)
- Impacted by education, language fluency, sensory deficits
- Must exclude medical history, blood tests, physical examination etc
Basic Idea of Alzheimer’s
- 1906, treated person dying of symptoms of memory loss, language problems and unpredictable behaviour
- Aggregation of proteins in abnormal fashion in Alzheimer’s, creation of amyloid plaques, neurofibrillary tangles
Criteria for Alzheimer’s
- Insidious onset and gradual progression of impairment
- Genetic mutation from family history
- No evidence of mixed etiology (absence of other neurodegenerative disease)
- Some may have the pathology but not the cognitive impairment, separating the disease from the dementia
- Separating positive biomarkers from cognition, finding AD specific features
Drugs Associated with Alzheimer’s
Human monoclonal antibodies
- Removes amyloid and shows statistically significant slowing in the decline in cognitive function
- Downside of regular monitoring (brain imaging) due to risk of small bleeds in the brain
Acetyl-cholinesterase inhibitors and NMDA
- No impact on the progression of the disease
Vascular Damage Leading to Dementia
- Stroke
- Damage to myelin sheath
- Damage to the lining of the blood vessels
- Impaired blood flow
- Damage to the blood brain barrier
- Managing changes in blood pressure
Highest Risk of Dementia
Highest risk is high blood pressure
- Because it associated with age
- Increases with age
- Drives vascular risk factors
- High blood pressure in mid life (40s etc) have higher risk of dementia in late life
Vascular Neurocognitive Disorder
- Consistent with vascular etiology
- Temporally related to one or more cerebrovascular events
- Complex attention (including processing speed) and frontal-executive function
- Evidence of the presence of cerebrovascular disease
Issues for Diagnosis of Dementia
- Prodromal and presymptomatic phase may last 20-30 years
- Maybe should be intervening 65 or younger to manage for 85 year mean
- Pathology does not map directly onto symptoms
- Most late onset dementia has mixed pathology
Lifestyle Risk Factors to Dementia
- Smoking
- Loss of hearing
- Sleep
- Alcohol
- Physical Inactivity