CNS: Dementia and Parkinsonism Flashcards
What is dementia?
a progressive, irreversible clinical syndrome with a range of cognitive and behavioural symptoms
What are some cognitive symptoms of dementia? (2)
Memory loss
Issues with reasoning/communication
What are some behavioural symptoms of dementia? (2)
Inability to carry out basic tasks
Change in personality
What is the most common type of dementia?
Alzheimer’s dementia
What are some common types of dementia (5)?
Alzheimer's Lewy-body dementia Vascular dementia Mixed dementia Frontotemporal dementia
Which commonly prescribed drug classes should be avoided in patients with dementia? (4)
Drugs with antimuscarinic effects, e.g.
Antidepressants, antihistamines, antipsychotics, antispasmodics
What drug class is first line for treatment for Alzheimer’s disease?
Acetylcholinesterase inhibitors (AChEIs)
What are the three AChEIs used as first line treatment for mild to moderate Alzheimer’s?
Donepezil
Galantamine
Rivastigmine
What is the STOPP criteria for all AChEIs? (4)
Heart block
Unexplained syncope
Persistent bradycardia
Concurrent treatment with drugs that reduce heart rate
What can be used in patients with moderate Alzheimer’s if AChEIs are not tolerated or contraindicated?
Memantine
What is the first line treatment for patients with severe Alzheimer’s?
Memantine
If patients on an AChEI for mild Alzheimer’s deteriorate, what drug can be added?
Memantine
Can medicines for dementia be prescribed in primary care/by a non-specialist?
Yes - addition of memantine to patient already on AChEIs
No - newly diagnosed patients
Why shouldn’t AChEIs be discontinued in patients with moderate Alzheimer’s?
Doing so can worsen cognitive function substantially
What are the first line drugs for mild, moderate and severe lewy-body dementia? (2)
Donepezil
Rivastigmine
When should galantamine be considered in lewy-body dementia?
When treatment with donepezil or rivastigmine is not tolerated
When should memantine be considered for use in lewy-body dementia?
When AChEIs are contraindicated or not tolerated
When should drug treatment be considered for patients with vascular dementia?
When they also have another form of dementia (Alzheimer’s, Parkinson’s or lewy-body)
What treatment is available for patients with frontotemporal dementia or cognitive impairment caused by MS?
None at the moment - AChEIs and memantine are not recommended in this group
What are some cholinergic side effects? (8)
Remember: DUMBBELS
Diarrhoea Urination Muscle weakness/cramps Bronchospasm Bradycardia Emesis (vomiting) Lacrimation (teary eyes) Salivation/sweating
When should antipsychotics be offered to patients with dementia? (2)
If they are at risk of harming themselves/others
If they are severely distressed due to hallucinations, delusions or agitation
What did an MHRA report conclude about elderly dementia patients on antipsychotics? (2)
There is an increased risk of stroke and a small increase in risk of death
How should antipsychotics in dementia patients be prescribed? (3)
Starting with the lowest effective dose
For the shortest time possible
With 6-weekly reviews
What is important to consider in Parkinson’s and lewy-body dementia patients re: antipsychotics?
Antipsychotics can worsen motor features
What four psychological treatments can be considered in dementia patients suffering with depression/anxiety?
CBT
Multisensory stimulation
Relaxation
Animal-assisted therapies
What should be offered to dementia patients with sleep disturbances? (3)
Sleep hygiene education
Exposure to daylight
Increasing exercise
What is the mechanism of action for memantine?
It is an NMDA glutamate receptor antagonist - limiting Ca2+ influx into the cell
What role does glutamate play in Alzheimer’s dementia?
Glutamate plays a role in membrane excitability and synaptic transmission
too much glutamate → too much Ca2+ being let into the post-synaptic nerve → cell bursts and dies
What are three main points for donepezil?
Take at bedtime
There is a rare risk of neuroleptic malignant syndrome (increased risk when taken with antipsychotics)
It is long acting, so usually only given once a day
What are two main points for rivastigmine?
Monitor body weight
Interrupt treatment if dehydration (due to D+V) occurs
How does galantamine differ from rivastigmine and donepezil?
It has nicotinic receptor agonist effects, as well as being an AChEI
What should patients on galantamine be warned of?
Serious skin reactions (e.g. SJS) - patients should stop taking and seek medical advice immediately
What is Parkinson’s disease?
A progressive, neurodegenerative condition caused by death of dopaminergic cells in the substantia nigra
What are some motor symptoms of Parkinson’s? (5)
Hypokinesia (less movement) Bradykinesia (slow movement) Rigidity Tremor at rest Postural instability
What are some non-motor symptoms of Parkinson’s? (6)
Dementia Sleep disturbances Changes in speech and language Swallowing issues Weight loss Bladder/bowel dysfunction
How often should patients with Parkinson’s be reviewed?
Every 6-12 months
Who should Parkinson’s patients inform about their diagnosis? (2)
The DVLA and their car insurer
What non-pharmacological treatment should be offered to patients with Parkinson’s? (3)
Physiotherapy
Speech and language therapy
Occupational therapy
What is the first line treatment for motor symptoms that affect quality of life in Parkinson’s?
Levodopa with carbidopa (co-careldopa) OR with benserazide (co-beneldopa)
Why does levodopa need to be given either either carbidopa or benserazide?
Carbidopa and benserazide inhibit peripheral metabolism of levodopa, increasing its chances of reaching the brain
What are the first line treatment options for motor symptoms that DO NOT affect quality of life in Parkinson’s? (3)
Levodopa
Non-ergot derived dopamine receptor antagonists
MOA-B inhibitors
How do non-ergot derived dopamine receptor agonists work?
They mimic dopamine and directly stimulate dopamine receptors
What are three examples of non-ergot derived dopamine receptor antagonists?
Ropinirole
Pramipexole
Rotigotine
How do MOA-B inhibitors work?
They inhibit the breakdown of dopamine in the synaptic cleft
What are two examples of MAO-B inhibitors?
Selegiline
Rasagiline
What ADRs should Parkinson’s patients be warned about before treatment? (3)
Excessive sleepiness/sudden onset of sleep
Psychotic symptoms
Impulse control disorders
(more common with non-ergot derived dopamine receptor antagonists)
Which Parkinson’s medication is associated with more motor complications?
Levodopa - response fluctuations and dyskinesia (on and off periods)
Which drug class is more effective in improving overall motor performance?
Levodopa > non-ergot derived dopamine receptor antagonists
Why should abrupt withdrawal of antiparkinsonian drugs be avoided? (2)
Abrupt withdrawal may increase the risk of acute akinesia or neuroleptic malignant syndrome
What antiemetic medication can be given to patients with Parkinson’s and why?
Domperidone (does not cross BBB ∴ does not cause extrapyramidal side effects)
What should happen when a patient with Parkinson’s develops dyskinesia or motor fluctuations? (2)
Specialist advice should be sought before changing their therapy
Adjunct therapy is considered
What can be given to patients with Parkinson’s who require adjunct therapy with levodopa?
Non-ergot dopamine receptor agonists (e.g. ropinirole) MOA-B inhibitors (e.g. rasagiline) COMT inhibitors (-capone)
When should ergot-derived dopamine receptors be considered as adjunct therapy?
Only when symptoms are not adequately controlled with a NON-ergotic dopamine receptor antagonist
Why aren’t ergot-derived dopamine receptor agonists preferred over non-ergot derived?
They cause fibrotic reactions (patients should be warned of pulmonary, retroperitoneal and pericardial side effects)
What is an example of a ergot-derived dopamine receptor antagonist?
Bromocriptine
When should amantadine be considered?
When dyskinesia is not adequately managed by modifying existing therapy
What drug can be offered to patients with advanced Parkinson’s?
Apomorphine (with domperidone started 2 days and discontinued ASAP)
What advice is given by the MHRA to patients on apomorphine and domperidone?
Assess cardiac risk factors and monitor ECG (can cause QT prolongation)
What are four important side effects of dopaminergic drugs?
Excessive daytime sleepiness
Impulse control disorders
Motor complications
End-of-dose deterioration
Which drug class of antiparkinsonian medication is more likely to cause side effects?
Dopamine receptor agonists
Have you taken a break today?
Don’t ignore the question - you won’t remember anything if you don’t take regular breaks 🥺
What foods are thought to cause hypertension when taken with MAO-B inhibitors?
Tyramine-rich foods (e.g. mature cheese, fermented food)
What drugs should be avoided by patients who are taking MAO-B inhibitors?
Anything that can cause hypertension
What are two examples of COMT inhibitors?
Entacapone
Tolcapone
How do COMT inhibitors work?
By inhibiting COMT they limit the metabolism of dopamine/levodopa
What should patients who use tolcapone be made aware of?
Signs of liver toxicity e.g. dark urine, pruritus, N&V
it’s hepatotoxic
What should patients using entacapone be made aware of?
It can make the colour of urine reddish-brown
What is co-careldopa gel indicated for?
How is it administered?
Advanced Parkinson’s with severe motor fluctuations and hyper- or dyskinesia
Via a portable pump directly to the duodenum or upper jejunum
What should happen if a patient develops a problematic impulse control disorder? (2)
Dopamine receptor agonist therapy should be reduced and stopped
Patients should be monitored for symptoms of dopamine agonist withdrawal
What are some examples of impulsive control disorders? (4)
Hypersexuality
Gambling
Excessive spending
Binge eating
