Parkinson's Disease Flashcards
Parkinson’s Disease is primarily a disorder of what function?
Movement
What is the mean age of onset for idiopathic Parkinson’s Disease?
60-65 (only 5% diagnosed
Parkinson’s Disease is the 2nd commonest neurodegenerative disease worldwide - 2nd to what?
Alzheimer’s disease
What is the triad of symptoms in Parkinson’s Disease?
Bradykinesia; Rigidity; Tremor (Postural instability is also very common, though perhaps not a cardinal feature)
Name 3 common sleep-associated problems seen in Parkinson’s patients
- poor sleep quality
- REM sleep behaviour disorder (act out dreams)
- Day time somnolence
What symptoms often arise from autonomic disturbance experienced in Parkinson’s?
Excessive sweating; Urinary disturbance; Constipation; Pain
List some neuropsychiatric symptoms of Parkinson’s
Apathy; Depression; Dementia; Psychotic Sx e.g hallucinations (also worsened by meds and Lewy-Body dementia)
In Parkinson’s Disease does tremor worsen on activity or at rest?
At rest
If a tremor worsens on performing an action what is a more likely diagnosis?
Essential tremor - NB head tremor common in essential tremor but jaw and tongue may be involved in PD
If rigidity is found on examination to be bilateral does that strengthen or weaken the likelihood of PD as a diagnosis?
It is less likely to be Parkinson’s - motor symptoms are much more frequently unilateral
What features of an individuals walk are likely to be seen in Parkinson’s?
Difficulty initiating movement; Slow pace; Shuffling; Reduced arm swing on affected side; Stooped posture
How might facial expression and speech help diagnose Parkinson’s Disease?
“Hypomimia” - Reduced expression, less frequent blinking > ‘mask-like’
Hypophonia - quiet speech
What is the difference between rigidity and hypertonia?
hypertonia is velocity dependent - hence flicking the leg in the air to test tone
Rigidity is non-velocity dependent
List some causes of secondary Parkinsonism
Vascular disease; Drugs e.g. Metoclopramide and Anti-psychotics; Post viral encephalitis; Head injuries; Hydrocephalus; Anoxia
List some differentials for tremor
Essential tremor - FHx; alleviated by alcohol; head; action
Thyrotoxicosis
Drug-induced - Salbutamol; Sodium Valproate; Caffeine
What are the 3 ‘Parkinson’s Plus Syndromes’?
1) Progressive Supranuclear Palsy
2) Multiple System Atrophy
3) Corticobasal Degeneration (brain cells die)
All pretty rare!
What are the key features of progressive supranuclear plasy?
no tremor
impaired upward gaze
often fall backwards - postural instability
What is the most important thing to discuss with patients when discussing management of Parkinson’s?
That medications are not curative and there is no neuroprotective medication (i.e. cannot change the course of the disease) Simply aimed at symptom control
How does Levodopa help in the management of Parkinson’s?
It increases Dopamine levels thereby restoring movement
Why does L-dopa have to be combined with a dopa decarboxylase?
Because L-dopa is metabolised extra-cerebrally and cannot cross the BBB, therefore needs Carbidopa or Benzarazide combined with it
What are the early more common side-effects seen in Parkinson’s patients on L-dopa prescriptions?
Nausea; hypotension; discolouration of urine
What are the later more concerning side-effects of L-dopa preparations?
80% have motor complications by 5-10yrs of treatment including: motor fluctuations, dyskinesis, neuropsychiatric problems
What is the alternative to L-dopa in the medical management of Parkinson’s?
Dopamine agonists
Name some commonly used dopamine agonists
Ropinarole - slow release once/daily prep
Pramipexole
Rotigine (Patch)
Apomorphine - subcut!
What are the indications for dopamine agonists in Parkinson’s?
Young patients (to delay motor SEs of L-dopa) Complex disease - added to L-dopa
What are the main side effects of dopamine agonists?
somnolence; nausea; hallucinations
Major problem - impulse control disorders (impulsive and compulsive behaviours - much more of a problem than with L-dopa)
When is Apomorphine used and how is it administered?
In complex phase of disease - when oral meds not effectively treating symptoms
Subcut: a) bolus for freezing episodes
b) continuous infusion to avoid fluctuations
What are COMT inhibitors and when are they used?
Catechol-o-methyltransferase inhibitors - blocks enzyme catechol-o-methyltransferase enzyme which degrades dopamine. :. increasing dopamine availability - always given with L-dopa to make L-dopa more effective - when drugs wearing off quickly / complex phase of disease
Side effects of COMT inhibitors?
Same as for L-dopa (dyskinesia; somnolence; fainting; N&V)
plus diarrhoea and elevated liver enzymes
Name the main two MAO-B inhibitors and state when it is used.
Rasagiline and Selegiline - less effective than L-dopa (increase dopamine abundance)
Young, mild disease
Late disease as adjunct
What is the main medical treatment used for Benign Essential Tremor?
Beta-Blockers
What is Deep Brain Stimulation?
A surgical procedure rarely used in Parkinson’s whereby stimulator electrodes are inserted into the Thalamus, Globus Pallidus or Subthalamic nucleus - tunnel wire behind ear to chest where impulse provided
Where does Deep Brain Stimulation Act?
Contralateral side to that in which implanted. Bilateral is rare as increased risk of speech loss
Name 3 other medication types that may be required in Parkinson’s - besides those to improve movement problems
- Anti-depressants
- Anti-cholinesterases (Donepezil; Galantamine; Rivastigmine)
- Stool softeners / laxatives
