Dementia Flashcards
Epidemiology
1% of total population >65% 6% >80% 20% Alzheimer's more common in women Vascular more in men
Types
Alzheimer's 62% Vascular 17% Mixed 10% Lewy body 4% Frontotemporal 2% Parkinson's 2%
Alzheimer’s disease causes
f 00.0 early onset 65
- cholinergic hypothesis-> degeneration of cholinergic neurones-> decreased acetylcholine
- amyloid hypothesis -> b-amyloid plaques and neurofibrillary tangle formation or hyperphosphorylated tau -> APOE4 is s genetic risk factor
- tau hypothesis-> tanlgles form inside neurones-> disturb communication-> neurone dies
- inflammation-> 70% loss of locus coeruleus cells-> decreased noradrenaline (usually acts as an anti inflammatory)
- herpes simplex
- myelin breakdown
- oxidative stress
Pathophysiology of Alzheimer’s disease
- loss of neurones in multiple regions
- amyloid plaque and tangle build up
- genetic factors
- late onset APOE4
- early onset amyloid precursors protein
Clinical features of Alzheimer’s
Amnesia Agnosia -> loss of sensory interpretation Aphasia Apraxia -> loss of skilled motor function Executive function loss - disinhibition -perseveration - apathy - dysexecuative syndrome Behavioural and psychological symptoms
Risk factors for Alzheimer’s
Cardiovascular -> smoking, hypertension, hypercholesterolemia, diabetes, history of mi
Head injury
Low educational attainment
Obesity
Vascular dementia distinguishing features
f01.0 vascular dementia of acute onset
f0.1.1 multi infarct disease
Higher mortality than AD
Focal neurological signs
Evidence of cv disease or stroke
Uneven or stepwise deterioration
Risk factors for vascular dementia
Smoking Hypertension Diabetes Hypercholesterolemia History of MI previous stroke AF Obesity
Lewy body dementia pathophysiology
Neuronal inclusions composed of abnormally phosphorylated neurofilament protiens aggregated with ubiquitin and a-synuclien
Loss of dopamine producing neurones in SN
Loss of acetylcholine producing neurones in basal nucleus of maynerts
Cerebral atrophy
Distinguishing features of Lewy body dementia
Day to day fluctuations Recurrent visual hallucinations Motor signs of Parkinson's Recurrent falls and syncope Transient disturbances of consciousness Extreme sensitivity to anti-psychotics
Roles of the frontal lobe
Personality Planning/sequencing Estimation Set shifting Non literal language appreciation Inhibition
Roles of the temporal lobe
Auditory processing
Visual processing
Semantics processing
Distinguishing features of frontotemporal dementia
Early decline in social and personal conduct Early emotional blunting Attenuated speech output Echolalia Perservation Mutism Early loss of insight Relative sparing of other cognitive functions
Variants of frontotemporal dementia
Behavioural -> lethargy and aspontinateity v. Disinhibition Progressive non fluent aphasia -> deterioration in speech fluency Semantic -> naming and word comprehension
Epidemiology of BPSD
40% of mild condition impairment
60% of early dementia
Effects 90-100% at some point
