Geriatrics fifth yr Flashcards
What is dementia?
irreversible, progressive decline and impairment of more than one aspect of higher brain function (concentration, memory, language, personality, emotion).
This occurs without impairment of consciousness
Biggest RF - increasing age
Can be proven post-mortem with histological evidence
Dx usually made clinically from Hx (pt and collateral), cognitive tests (10-CS, 6CIT), and formal neuropsychological assessment
Summary of Alzheimer’s dementia?
Most common cause of dementia in the UK - half of dementia diagnoses
F>M
Progresses steadily over time
Aetiology - amyloid plaques and neurofibrillary tangles (made from tau protein) accumulate - reduces information transmission, leading to death of brain cells, and abnormal deposits remain post-mortem
Macroscopic changes - widespread cerebral atrophy, particularly cortex and hippocampus
Microscopic - cortical plaques due to deposition of type A-Beta-amyloid protein and intraneuronal neurofibrillary tangles caused by abnormal aggregation of the tau protein
hyperphosphorylation of the tau protein has been linked to AD
Biochemical - deficit of acetylcholine from damage to an ascending forebrain projection
Features - >60 (early onset too), affects all areas of the brain (many functions/abilities impacted and lost)
Most common presenting Sx is memory loss - varying changes in planning, reasoning, speech and orientation
Summary of vascular dementia?
Second most common
M>F - due to increased risk of vascular disease
^ prevalence in those who have had a stroke
Step wise fashion - stability, decline, stability
Aetiology - subtypes - most common stroke related (multiple cerebrovascular infarcts), subcortical VD (small vessel disease), mixed dementia (presence of VD and Alzheimers)
most affected areas - white matter of cerebral hemispheres, grey nuclei, thalamus and striatum
RF - HTN, vascular RFs = smoking, DM, hyprelipidaemia, obesity, hypercholesterolaemia
Features - single infarct vascular disease presents with cognitive impairment following event, mood disturbances/disorders, psychosis, delusions, hallucinations, paranoia
Pts should be screened for depression and signs of psychomotor retardation. Emotional lability can be prominent
Summary of Lewy body dementia?
Pt > 50
M>F
Rapidly progressive - death common in first 7 years post-diagnosis
Aetiology - spherical Lewy body proteins deposited in brain. Also present in Parkinsons (mainly in substantia nigra) while in Lewy body dementia they are widespread
Features - visual hallucinations, Parkinsonism (if physical Sx precede cognitive decline by more than a year, Dx is Parkinson’s with superimposed cognitive decline)
problems multitasking and performing complex cognitive actions are primary issue (rather than memory)
sleep disorders
Fluctuations in cognitive ability
Dx - clinical, SPECT
Tx - both acetylcholinesterase inhibitors (e.g. donepezil, rivastigmine) and memantine can be used as they are in Alzheimer’s.
neuroleptics should be avoided in Lewy body dementia as patients are extremely sensitive and may develop irreversible parkinsonism.
Summary of frontotemportal dementia?
Less common
Responsible for Dx of dementia <65
Insidious onset
M=F
Average life expectancy is 8 years post-diagnosis
Several types, Frontotemporal dementia (Picks disease), progressive non fluent aphasia, semantic dementia
Aetiology - neutron damage and death in frontal and temporal lobes. Atrophy due to deposition of abnormal proteins within lobes. Genetic component in 1/4 cases
Features - one of 3 clinical pictures:
- behavioural - altered emotional responsiveness, apathy, disinhibition, impulsivity, progressive decline in interpersonal skills, changes in food preference, more childlike amusements, obsessions + rituals
- semantic - progressive decline in understanding of words, speech fluent but difficulty in name-retrieval and use of less precise terms, unable to determine meanings of common words, develops to inability to recognise objects or familiar faces (prosopagnosia)
- non-fluent prevention - progressive breakdown in output of language, speech takes effort and not fluent, speech apraxia, impaired comprehension of sentence and impact on literacy skills
Differential diagnoses for dementia?
Prion protein diseases - Creutzfeldt-Jakob disease
Sporadic CJD - over age of 40
Variant - eating meat infected by bovine spongiform encephalopathy
Differential diagnoses for dementia?
Prion protein diseases - Creutzfeldt-Jakob disease
HIV-related cognitive impairment/dementia - mild cognitive impairment, mood disturbance
Normal pressure hydrocephalus
Severe depression
Mild cognitive impairment - not severe enough to interfere with every day life. Yearly, 10-15% of people with mild cognitive impairment go on to develop form of clinical dementia. Causes - stroke, depression, stress, physical illness, drug SE
Huntingtons
Potentially treatable:
Hypothyroidism, Addisons, B12/folate/thiamine deficiency, syphilis, brain tumour, subdural haematoma, chronic drug use (alcohol, barbiturates)
Summary of normal pressure hydrocephalus?
Caused by abnormal build-up of CSF in ventricles - causing increased pressure and producing Sx of cognitive impairment
Occur at any age, but more common in elderly
RF - head trauma, infection or inflammation in brain, tumour and SAH
Features - progressively worsening memory lapses, personality and mood disturbances, difficulties with walking, dementia, urinary incontinence
Ix - imaging - hydrocephalus with ventriculomegaly in absence of, our out of proportion to, sulcal enlargement
Tx - ventriculoperitoneal shunt to drain excess CSF into abdomen
Ix for dementia?
Primary -
Blood (reversible causes) - FBC, U&E, LFTs, calcium, glucose, ESR/CRP, TFTs, vitamin B12, folate
Secondary -
Neuroimaging to exclude other reversible conditions (subdural haematoma, normal pressure hydrocephalus)
Management of Alzheimers disease?
Lifestyle - range of activities to promote wellbeing that are tailored to person’s preference, group cognitive stimulation
Pharmacological-
- acetylcholinesterase inhibitors (donepezil, galantamina, rivastigmine)
- donepezil - contraindicated in pt’s with bradycardia, SE = insomnia
- memantine (NMDA receptor antagonist) - second line
Managing non-cognitive Sx
- NICE don’t recommended antidepressants
- antipsychotics should only be used for patients at risk of harming themselves or others, or when the agitation, hallucinations or delusions are causing them severe distress
Summary of pellagra?
Caused by nicotinic acid (niacin) deficiency
Three D’s - dermatitis, diarrhoea, dementia
may occur as a consequence of isoniazid therapy (isoniazid inhibits the conversion of tryptophan to niacin) and it is more common in alcoholics.
Summary of Pick’s disease?
Frontotemporal dementia
Sx - personality change, impaired social conduct, hyperorality, disinhibition, increased appetite, perseveration behaviours
Focal gyral atrophy with knife-blade appearance
Macroscopic changes - Atrophy of the frontal and temporal lobes
Microscopic changes - Pick bodies (spherical aggregations of tau protein), gliosis, neurofibrillary tangles, senile plaques
Tx
NICE do not recommend that AChE inhibitors or memantine are used in people with frontotemporal dementia
Management of vascular dementia?
Address CVD RFs to slow progression
Non-pharmacological - cognition stimulation programmes, multi sensory stimulation, music/art therapy, animal therapy
managing challenging behaviours - address pain, avoid overcrowding, clear communication
Pharmacological - no specific Tx approved. Only consider AChE inhibitors or memantine for people with vascular dementia if they have suspected comorbid Alzheimer’s disease, Parkinson’s disease dementia or dementia with Lewy bodies.
Delirium vs dementia?
Factors favouring delirium over dementia:
acute onset
impairment of consciousness
fluctuation of symptoms: worse at night, periods of normality
abnormal perception (e.g. illusions and hallucinations)
agitation, fear
delusions
Depression vs dementia?
Factors suggesting diagnosis of depression over dementia:
short history, rapid onset
biological symptoms e.g. weight loss, sleep disturbance
patient worried about poor memory
reluctant to take tests, disappointed with results
mini-mental test score: variable
global memory loss (dementia characteristically causes recent memory loss)
