Geris Flashcards
What is Lewy Body Dementia
Lewy body dementia is an increasingly recognised cause of dementia, accounting for up to 20% of cases. The characteristic pathological feature is alpha-synuclein cytoplasmic inclusions (Lewy bodies) in the substantia nigra, paralimbic and neocortical areas.
What is the relationship between LBD and PD?
The relationship between Parkinson’s disease and Lewy body dementia is complicated, particularly as dementia is often seen in Parkinson’s disease. Also, up to 40% of patients with Alzheimer’s have Lewy bodies.
What are the features of LBD?
progressive cognitive impairment
typically occurs before parkinsonism, but usually both features occur within a year of each other. This is in contrast to Parkinson’s disease, where the motor symptoms typically present at least one year before cognitive symptoms
cognition may be fluctuating, in contrast to other forms of dementia
in contrast to Alzheimer’s, early impairments in attention and executive function rather than just memory loss
parkinsonism
visual hallucinations (other features such as delusions and non-visual hallucinations may also be seen)
How do you diagnose LBD?
usually clinical
single-photon emission computed tomography (SPECT) is increasingly used. It is currently commercially known as a DaTscan. Dopaminergic iodine-123-radiolabelled 2-carbomethoxy-3-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123-I FP-CIT) is used as the radioisotope. The sensitivity of SPECT in diagnosing Lewy body dementia is around 90% with a specificity of 100%
What is the management of LBD?
both acetylcholinesterase inhibitors (e.g. donepezil, rivastigmine) and memantine can be used as they are in Alzheimer’s. NICE have made detailed recommendations about what drugs to use at what stages. Please see the link for more details
neuroleptics should be avoided in Lewy body dementia as patients are extremely sensitive and may develop irreversible parkinsonism. Questions may give a history of a patient who has deteriorated following the introduction of an antipsychotic agent
Which drugs should be used with caution in dementia?
Antipsychotics are associated with a significant increase in mortality in dementia patients and should only be used with caution for patients at risk of harming themselves or others, or when the agitation, hallucinations, or delusions are causing them severe distress as in this case.
What is vascular dementia
Vascular dementia (VD) is the second most common form of dementia after Alzheimer disease. It is not a single disease but a group of syndromes of cognitive impairment caused by different mechanisms causing ischaemia or haemorrhage secondary to cerebrovascular disease. Vascular dementia has been increasingly recognised as the most severe form of the spectrum of deficits encompassed by the term vascular cognitive impairment (VCI). Early detection and an accurate diagnosis are important in the prevention of vascular dementia.
What is the epidemiology of Vascular Dementia?
VD is thought to account for around 17% of dementia in the UK
Prevalence of dementia following a first stroke varies depending on location and size of the infarct, definition of dementia, interval after stroke and age among other variables. Overall, stroke doubles the risk of developing dementia.
Incidence increases with age
What are the subtypes of Vascular Dementia?
Stroke-related VD - multi-infarct or single-infarct dementia
Subcortical VD - caused by small vessel disease
Mixed dementia - the presence of both VD and Alzheimers disease
What are the risk factors for vascular dementia?
History of stroke or transient ischaemic attack (TIA)
Atrial fibrillation
Hypertension
Diabetes mellitus
Hyperlipidaemia
Smoking
Obesity
Coronary heart disease
A family history of stroke or cardiovascular
