Dementia Flashcards
Alzheimers epidemiology?
Slightly more common in females
The most common cause of dementia in the UK accounting for about half of all dementia diagnoses.
Alzheimers PPx?
Amyloid plaques develop between neurons.
Neurofibrillary tangles made of tau protein develop within within neurons
The accumulation of these leads reduction in transmission of information, and eventually to the death of brain cells
Vascular dementia epidemiology?
More common in males
second most common type of dementia.
Increased prevalence in those who have had a stroke (9x higher than the general population).
Vascular dementia types?
Stroke-related VD – multi-infarct or single-infarct dementia
Subcortical VD – caused by small vessel disease
Mixed dementia – the presence of both VD and Alzheimer’s disease
Vascular dementia features?
Single infarct vascular disease: classically cognitive impairment (acutely or subacutely) following the event.
Functional deficits are often seen before memory impairment
Mood disturbances and mood disorders are common in vascular dementia.
Psychosis, delusions, hallucinations and paranoia can often be seen, especially in later stages.
Patients should be screened for depression and for signs of psychomotor retardation (often a more common feature than positive signs of depression).
Emotional lability can be prominent.
Vascular dementia progression?
‘Stepwise’ – often shows a period of stability at one level of functioning, before an acute decline progression, followed by another period of stability.
Lewy-body dementia epidemiology?
Appears to affect slightly more men than women.
Mostly affects those over the age of 50.
LBD PPx?
Spherical “Lewy Body” proteins are deposited in the brain (alpha-synuclein)
These Lewy Bodies are also present in Parkinson’s disease – the difference being that in Parkinson’s they are mainly deposited in the substantia nigra, whereas they are more widespread in Lewy-Body dementia.
Features of lewy body and progression?
Often involves visual hallucinations and Parkinson-like symptoms.
If physical symptoms precede cognitive decline by more than a year, the diagnosis is often Parkinson’s, with superimposed cognitive decline.
Fluctuation in cognitive ability is common.
At presentation, problems multitasking and performing complex cognitive actions are more likely to the primary issue (rather than memory).
Sleep disorders are a common manifestation.
Fairly rapidly progressive, with death most commonly in the first 7 years post-diagnosis.
Mixed dementia dx?
diagnosed when patients have evidence of more than one type of dementia (often Alzheimer’s and vascular dementia) based upon clinical or neuroimaging evidence.
Frontotemporal dementia epidemiology?
Much less common type, but responsible for a significant number of diagnoses of dementia in under 65s.
Tends to affect both sexes equally.
PPx of frontotemporal dementia?
Neuron damage and death in the frontal and temporal lobes.
The atrophy is due to deposition of abnormal proteins (often tau protein) within the lobes.
Features of Frontotemporal dementia?
Behavioural presentation: Altered emotional responsiveness, apathy, disinhibition, impulsivity; Progressive decline noted in interpersonal skills.; Changes in food preference, more childlike amusements.
Obsessions and rituals may also be noted.
Semantic presentation: Progressive decline in the understanding of word meanings;
Speech may still be fluent, but there is difficulty in name-retrieval and use of less precise terms;
Unable to determine the meanings of common words when asked.
This tends to develop into the inability to recognise objects, or familiar faces (prosopagnosia).
Non-fluent presentation: Progressive breakdown in the output of language.
Generally display speech apraxia (poor articulation) or disorders of speech sound.
impaired comprehension of sentences and an impact on literacy skills.
Over time, all three initial presentations tend to emerge and worsen.
Dementia differentials?
Prion Protein Diseases (eg. Creutzfeldt-Jakob Disease)
HIV-related Cognitive Impairment/Dementia
Normal Pressure Hydrocephalus
Severe Depression
Mild Cognitive Impairment
Cause of variant CJD? What’s the other type called? Features of disease?
eating meat infected by bovine spongiform encephalopathy
Sporadic CJD - affects those over the age of 40
To begin with, it may present as minor memory lapses, mood disturbance and loss of interest. followed by (over weeks) unsteadiness, physical clumisiness
Progression then involves stiffness, jerking movements, incontinence and aphasia.