Dementia + Alzheimers Flashcards
what is dementia
syndrome encompassing progressive deficits in several cognitive domains
what is the prevalence
5-10% if >65; 20% if >80; 70% if >100
diagnosis- history
timeline of progression, what was noticed first, what found most difficult. ADLs affected. may be aggression, agitation, wandering, hallucinations, apathy, mood disturbance
what can be used in diagnosis
cognitive testing (AMTS- abbreviated mental test score, TYM, verbal recall, executive function); mental state exam (anxiety, depression, hallucination); physical exam (physical cause for impairment, risk factors, parkinsonism)
investigations
FBC, ESR, U&E, LFT, TSH, autoantibodies, B12/folate, syphilis. CT/MRI. EEG. CSF, functional imaging. Metabolic genetic and HIV tests if indicated
commonest causes
Alzheimers, vascular dementia, lew body, fronto temporal.
other causes
alcohol/drug abuse, repeated head trauma, pellagra, Whipples disease, Huntingtons, CJD, Parkinsons, HIV
what % of dementias are vascular
25%. cumulative effects of many small strokes, so sudden onset and deterioration. look for incr BP, past strokes, focal CNS signs
what % of dementias are Lewy body
15-25% third most common after Alzheimers and vascular.
what do you see in Lewy body dementia
fluctuating cognitive impairment, detailed visual hallucinations, parkinsonism. histology- Lewy bodies in the brainstem and neocortex
what is Fronto temporal (Picks) dementia
frontal and temporal atrophy without Alzheimers histolo;gy. signs- executive impairment, behaviour change, disinhibition, hyperorality, stereotyped behaviour
what is common in dementia
depression- try an SSRI eg citalopram
what drugs should be avoided that impair cognition
neuroleptics, sedatives, tricyclics
what can be given if patients get very agitated
first rule out pain and infection as cause of behaviour. consider- trazodone, lorazepam. antipyschotics may help but cognition, verbal fluency etc will be worsened, Haloperidol useful in short term
what drugs should you avoid in Lewy Body
antipsychotics. some evidence that anti cholinesterase inhibitors may help
Alzheimers- when should you suspect this instead of other dementias
when enduring, progressive and global cognitive impairment- whereas other dementias which may affect some areas but not all
Alzheimers- what is the presentation
visuo-spatial skill lost, memory, verbal abilities and executive function affected, anosognosia (lack of insight into problems)
Alzheimers- later signs
irritability, mood disturbance, behaviour change, psychosis, agnosia
Alzheimers- cause
environmental and genetic factors. B amyloid peptide accumulation- neuronal damage, neurofibrillary tangles, incr number amyloid plaques, loss neurotransmitter Ach. defective clearance plaques by macrophages
what % of alzheimers patients show evidence of vascular dementia
95%
Alzheimers- risk factors
1st degree relative, Downs, homozygosity for ApoW e4 allele, PICALM, CL1 and CL2 mutations, vascular risk factors, decr physical/cognitive activity, depression
pharmacological treatment cognitive decline
anticholinesterase inhibitors- donepezil, rivastigmine, galantamine. antiglutamatergic treatment- memantine. targeting B amyloid. Folic acid and B vitamins
