Parkinsonism and Movement Disorders

Question 1

what is role of basal ganglia?

Answer 1

involved in initiation of movements and modulation of movement

they receive input from cerebral cortex, process it and relay it back to cerebral cortex via thalamus

Question 2

what is the most common neurodegenerative disease?

Answer 2

alzheimers

Question 3

what is cause of parkinson’s?

Answer 3

it is mostly idiopathic with some link to genetic and environmental factors

Question 4

what is the pathological hallmark of parkinsons?

Answer 4

sections through brainstem reveal loss of the normally dark pigment in the substantia nigra and locus coeruleus

this pigment loss correlates with dopaminergic cell loss

Question 5

what is a neurohistological hallmark of PD?

Answer 5

lewy bodies

Question 6

what are the motor symptoms of PD?

Answer 6

tremor

bradykinesia

rigidity

postural instability

Question 7

what are the non motor symptoms of PD?

Answer 7

sleep disorders

hallucinations

GI dysfunction

depression

cognitive impairment - dementia

constipation

anosmia

Question 8

approx 60% loss of dopaminergic neurones results in PD - where are these neurones actually lost from?

Answer 8

pars compacta region of substantia nigra

Question 9

what are the 2 broad subtypes of PD motor symptoms?

Answer 9

tremor dominant (with absence of other motor symptoms)

non-tremor dominant (such as akinetic-rigid syndrome)

Question 10

what are essential features for a diagnosis of PD?

Answer 10

bradykinesia (unilateral onset) and one more of:

resting tremor
rigidity (cogwheel or lead-pipe)
postural instability

Question 11

what are additional motor features which could aid diagnosis of PD?

Answer 11

stooped, fixed posture 
dystonic postures 
hypomimia ("masked face")
shuffling 
short-stepped gait (+/- festination)

Question 12

what are additional non-motor features which could aid diagnosis of PD?

Answer 12

late onset hyposmia 
depression and anxiety 
constipation 
bladder problems 
pain 
subtle mental or cognitive impairment

Question 13

how do you confirm PD diagnosis?

Answer 13

parkinsonism (features)
no alternative explanation
dopamine responsiveness

Question 14

what should patients not present with?

Answer 14

early-onset bulbar problems, dementia and hallucinations, preferential involvement of lower limb
prominent eye movement disorder
intrusive early autonomic problems

Question 15

diagnostic tests usually not needed but what could possibly be helpful?

Answer 15

structural brain imaging

SPECT (DaTSCAN) - normal is comma shaped. Period shape = possible PD

Question 16

do patients with PD have increased life span?

Answer 16

no - decreased

Question 17

what is risk factors for PD?

Answer 17

advancing age

positive family history (if <40 = probably genetic cause)

male gender

environmental factors (pesticide, head injury, rural living, b blocker use, agricultural occupation, well water drinking)

Question 18

what environmental factors decrease risk of PD?

Answer 18

tobacco smoking 
coffee drinking 
NSAID use 
CCB use 
alcohol consumption

Question 19

what is the most relevant genes in PD?

Answer 19

autosomal dominant = LRRK2

autosomal recessive = PARKIN

Question 20

what drugs can be used to symptomatically treat PD by enhancing intracerebral dopamine or stimulate dopamine receptors?

Answer 20

levodopa
dopamine agonist
monoamine oxydase type B inhibitors
amantadine (less common)

Question 21

when should treatment be initiated?

Answer 21

when symptoms cause disability or discomfort

Question 22

what symptoms respond reliably to dopaminergic treatment early in disease?

Answer 22

bradykinesia and rigidity

Question 23

tremor is inconsistently responsive to dopamine replacement - what could be more effective?

why reluctant to use these?

Answer 23

anticholinergic agents
trihexyphenidyl
clozapine

nasty side effects

Question 24

what are side effects of dopamine agonist and levodopa?

Answer 24

nausea
daytime somnolence
oedema

Question 25

what behaviours associated with dopamine agonist?

Answer 25

impulse control disorders inc pathological gambling
hypersexuality
binge eating
compulsive spending

Question 26

when should dopamine agonists be avoided?

Answer 26

patients with history of addiction, obsessive-compulsive disorders and impulse personality

Question 27

why should dopamine agonists not be prescribed in elderly?

Answer 27

because they are also associated with hallucination

especially shouldnt be given in those with cognitive impairment

Question 28

what drug provides greatest symptomatic benefit?

what is longterm use of this drug associated with?

Answer 28

levodopa

associated with motor complications (dyskinesia and motor fluctuations)