Parkinson's Disease

Question 1

Clinical features of movement disorders

Answer 1

• Bradykinesia: slowness of movement
• Muscle rigidity
• Resting tremor
• Postural instability with no other cause
• Anosmia: loss of sense of smell
• Depression
• Constipation
• Mask-like face
• Quiet dysarthric voice: slurred or slow speech that can be difficult to understand
• Micrographia: abnormally small, cramped handwriting or the progression is continually smaller handwriting
• Gait problems/falls
• Dementia (advanced disease)

Question 2

Diagnostic criteria for PD

Answer 2

Bradykinesia (upper body)
Slowness of movement
AND

Muscle rigidity (cog wheel) OR
Resting tremor (4-6Hz)
OR
Postural instability with no other cause (Pull test)

Question 3

Features that support the diagnosis of PD

Answer 3

Unilateral onset
Rest tremor present
Progressive
Persistent asymmetry

Excellent response to levodopa
Levodopa response for 5-years or more
Clinical course of 10 years or more

other, nonmotor symptoms appear with time: cognitive changes, psychiatric disorders, sleep disorders, constipation

Question 4

What is SPECT scanning

Answer 4

DAT (Dopamine active transporter) is located on the pre-synaptic terminals on dopaminergic neurones. [123I] beta-CIT is a radiolabelled cocaine derivative that binds to DAT

Degeneration of the nigrostriatal neurones will be associated with reduced ligand binding

Question 5

Aetiology of movement disorders

Answer 5

Combination of genetic predisposition and environmental factors

Environmental factors:
Pesticides
Infections (post-encephalitic)
Head injury

Protective factors:
smoking and caffeine

Question 6

Pharmacological management of PD

Answer 6

Treatment is symptomatic

Increase in synaptic dopamine.

Levo-dopa (1st line): replace dopamine using peripheral decarboxylase inhibitor to prevent peripheral breakdown

Dopamine agonists (rotigotine and ropinorole): active post-synaptic receptors (have psychiatric side effects eg hallucinations)

MAO-B inhibitors
Amantadine

Question 7

Effects of levodopa

Answer 7

Dramatic improvement in stiffness and may improve tremor but less so.

Max dose 600-1000mg/day
Given with Carbidopa or Benseridase (blocks Dopa decarboxylase so it crosses BBB)

Side effects:
N+V
Postural hypotension
Hallucinations
Confusion
Motor SE in prolonged use: dyskinesia, motor fluctuations (on/off)

Question 8

Non-pharmacological management

Answer 8

CGA
Social support and care. offer counselling
Driving (unless freezing)
Education/advice

OT (equipment, environment)
Physio - esp falls

Non-motor symptom control: constipation, sleep, autonomic dysfunction, mood, dementia (rivastigmine)

Question 9

How are dopamine agonists available, and what are SEs

Answer 9

Ropinerole, Pramipexole, Rotigotine patch, Apomorphine Subcut

Nausea
Postural dizziness
Hallucinations
Ankle swelling
Somnolence
13% Impulse control disorder

Motor problems: can wear off, fluctuations, freezing, dyskinesia

Other: conspitation, depression, dysphagia, drooling, dysphonia, postural hypotension, seborrhoeic dermatitis, sexual dysfunction

Question 10

What is essential tremor

Answer 10

A movement disorder
50% have FH

Postural, not resting.
Affects arms/head.
Better after alcohol.
Will not progress to any other symptoms.
Slightly responds to beta-blockers.

Question 11

What is vascular parkinsonism

Answer 11

Due to small vessel ischaemia

Associated with atherosclerotic RF

Causes falls, voice changes and early cognitive deficits

Legs more affected than arms

Stepwise, rapid progression

Poor response to RF

Question 12

What is drug-induced Parkinsonism

Answer 12

Parkinson’s due to lack of dopamine

eg. anti-psychotics and anti-emetics

Most resolve when drugs is stopped.
Qeutiapine is lowest risk

Question 13

What is Lewy body dementia

Answer 13

Dementia before parkinsonism

Visual hallucinations, worsened by antipsychotics!