Parkinson's Disease

Question 1

Parkinson’s Disease is primarily a disorder of what function?

Answer 1

Movement

Question 2

What is the mean age of onset for idiopathic Parkinson’s Disease?

Answer 2

60-65 (only 5% diagnosed

Question 3

Parkinson’s Disease is the 2nd commonest neurodegenerative disease worldwide - 2nd to what?

Answer 3

Alzheimer’s disease

Question 4

What is the triad of symptoms in Parkinson’s Disease?

Answer 4

Bradykinesia; Rigidity; Tremor (Postural instability is also very common, though perhaps not a cardinal feature)

Question 5

Name 3 common sleep-associated problems seen in Parkinson’s patients

Answer 5

• poor sleep quality
• REM sleep behaviour disorder (act out dreams)
• Day time somnolence

Question 6

What symptoms often arise from autonomic disturbance experienced in Parkinson’s?

Answer 6

Excessive sweating; Urinary disturbance; Constipation; Pain

Question 7

List some neuropsychiatric symptoms of Parkinson’s

Answer 7

Apathy; Depression; Dementia; Psychotic Sx e.g hallucinations (also worsened by meds and Lewy-Body dementia)

Question 8

In Parkinson’s Disease does tremor worsen on activity or at rest?

Answer 8

At rest

Question 9

If a tremor worsens on performing an action what is a more likely diagnosis?

Answer 9

Essential tremor - NB head tremor common in essential tremor but jaw and tongue may be involved in PD

Question 10

If rigidity is found on examination to be bilateral does that strengthen or weaken the likelihood of PD as a diagnosis?

Answer 10

It is less likely to be Parkinson’s - motor symptoms are much more frequently unilateral

Question 11

What features of an individuals walk are likely to be seen in Parkinson’s?

Answer 11

Difficulty initiating movement; Slow pace; Shuffling; Reduced arm swing on affected side; Stooped posture

Question 12

How might facial expression and speech help diagnose Parkinson’s Disease?

Answer 12

“Hypomimia” - Reduced expression, less frequent blinking > ‘mask-like’
Hypophonia - quiet speech

Question 13

What is the difference between rigidity and hypertonia?

Answer 13

hypertonia is velocity dependent - hence flicking the leg in the air to test tone
Rigidity is non-velocity dependent

Question 14

List some causes of secondary Parkinsonism

Answer 14

Vascular disease; Drugs e.g. Metoclopramide and Anti-psychotics; Post viral encephalitis; Head injuries; Hydrocephalus; Anoxia

Question 15

List some differentials for tremor

Answer 15

Essential tremor - FHx; alleviated by alcohol; head; action
Thyrotoxicosis
Drug-induced - Salbutamol; Sodium Valproate; Caffeine

Question 16

What are the 3 ‘Parkinson’s Plus Syndromes’?

Answer 16

1) Progressive Supranuclear Palsy
2) Multiple System Atrophy
3) Corticobasal Degeneration (brain cells die)
All pretty rare!

Question 17

What are the key features of progressive supranuclear plasy?

Answer 17

no tremor
impaired upward gaze
often fall backwards - postural instability

Question 18

What is the most important thing to discuss with patients when discussing management of Parkinson’s?

Answer 18

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

Question 19

How does Levodopa help in the management of Parkinson’s?

Answer 19

It increases Dopamine levels thereby restoring movement

Question 20

Why does L-dopa have to be combined with a dopa decarboxylase?

Answer 20

Because L-dopa is metabolised extra-cerebrally and cannot cross the BBB, therefore needs Carbidopa or Benzarazide combined with it

Question 21

What are the early more common side-effects seen in Parkinson’s patients on L-dopa prescriptions?

Answer 21

Nausea; hypotension; discolouration of urine

Question 22

What are the later more concerning side-effects of L-dopa preparations?

Answer 22

80% have motor complications by 5-10yrs of treatment including: motor fluctuations, dyskinesis, neuropsychiatric problems

Question 23

What is the alternative to L-dopa in the medical management of Parkinson’s?

Answer 23

Dopamine agonists

Question 24

Name some commonly used dopamine agonists

Answer 24

Ropinarole - slow release once/daily prep
Pramipexole
Rotigine (Patch)
Apomorphine - subcut!

Question 25

What are the indications for dopamine agonists in Parkinson’s?

Answer 25

Young patients (to delay motor SEs of L-dopa)
Complex disease - added to L-dopa

Question 26

What are the main side effects of dopamine agonists?

Answer 26

somnolence; nausea; hallucinations
Major problem - impulse control disorders (impulsive and compulsive behaviours - much more of a problem than with L-dopa)

Question 27

When is Apomorphine used and how is it administered?

Answer 27

In complex phase of disease - when oral meds not effectively treating symptoms
Subcut: a) bolus for freezing episodes
b) continuous infusion to avoid fluctuations

Question 28

What are COMT inhibitors and when are they used?

Answer 28

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

Question 29

Side effects of COMT inhibitors?

Answer 29

Same as for L-dopa (dyskinesia; somnolence; fainting; N&V)
plus diarrhoea and elevated liver enzymes

Question 30

Name the main two MAO-B inhibitors and state when it is used.

Answer 30

Rasagiline and Selegiline - less effective than L-dopa (increase dopamine abundance)
Young, mild disease
Late disease as adjunct

Question 31

What is the main medical treatment used for Benign Essential Tremor?

Answer 31

Beta-Blockers

Question 32

What is Deep Brain Stimulation?

Answer 32

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

Question 33

Where does Deep Brain Stimulation Act?

Answer 33

Contralateral side to that in which implanted. Bilateral is rare as increased risk of speech loss

Question 34

Name 3 other medication types that may be required in Parkinson’s - besides those to improve movement problems

Answer 34

• Anti-depressants
• Anti-cholinesterases (Donepezil; Galantamine; Rivastigmine)
• Stool softeners / laxatives