Dementia Flashcards
Four most common dementias in order of prevalence
Alzheimer’s
Vascular
Dementia with Lewy bodies
Frontotemporal dementia
Three categories of symptoms in dementia
Cognitive impairment
Psychiatric or behavioural disturbance
Difficulty with ADL
How should cognitive impairment be assessed?
Comprehensive history (include collateral) Tests include: MMSE, AMT, informant questionnaire on cognitive decline in the elderly, MoCA
Tests to exclude reversible causes (7)
FBC ESR/CRP LFTs Glucose Thyroid Calcium B12 and folate
Potentially treatable dementias (7)
Hypothyroidism SOLs Normal pressure hydrocephalus Syphilis Vit B12 deficiency Folate deficiency Pellagra
Imaging modality of choice for dementia
CT
Alzheimer’s disease
a) structural imaging
b) functional imaging
a) medial temporal atrophy, progressing to whole brain atrophy and ventricular dilatation
b) temporoparietal hypo-perfusion and hypo-metabolism
Pathological signs seen in Alzheimers
Amyloid plaques and neurofibrillary tangles
ACh-rich area of the forebrain whose degeneration is thought to be partly responsible for the decline in cognitive function seen in Alzheimers
Nucleus basalis of Meynert
Mainstay of pharmacological treatment of Alzheimers
Cholinesterase inhibitors e.g. donepezil, rivastigmine, galantamine
Common side effects of cholinesterase inhibitors
GI upset, tiredness, headache, sleep disturbance, bradycardia
How does memantine work?
Blocks NMDA-type glutamate receptors
How can vascular dementia be distinguished?
Stepwise symptom progression; use of the Hachinski ischaemic score
How is Lewy body dementia and dementia in Parkinson’s disease distinguished?
In DLB, the cognitive impairment occurs at around the same time as the movement disorder; in PD, the movement disorder predates the cognitive impairment
