Parkinson's and Movement Disorders Flashcards
(36 cards)
What are the classical symptoms of parkinson’s disease?
Asymmetrical bradykinesia
Hypokinesia
rigidity (cog-wheel)
tremor (pill rolling)
gait (shuffle)
What are the non-motor sx of parkinsons disease?
Constipation
REM sleep disturbances
PLMS/RLS
hyposmia
Depression/anxiety
What are the non-dopamine related sx of parkinson’s disease?
Posture disturbances
dec autonomic function
speech changes
cognitive changes
Pain
seborrhoea
weight loss
fatigue
What is an essential tremor?
Neurological cause of action tremor different from parkinsons
Describe the pathophysiology of parkinson’s disease?
Dopamine depletion from basal ganglia –> disrupt connection to thalamus and motor cortex –> parkinsonians signs
DA depletion in substantia nigra and nigrostriatal pathway –> inc inhibition of thalamus, reduced excitatory input into motor cortex –> bradykinesia and other parkinsonian signs
What is the role of the nigrostriatal pathway?
Nigrostriatal pathway = coordination of movement
hypokinesia of intentional movement and resting tremor
What is the role of the mesocortic pathway?
attention, cognition
What is the role of the mesolimbic pathway?
pleasure response
What is the role of the tuberoinfundibular pathway?
sexual dysfunction
Does parkinsons disease have more DA or ACH?
Hypokinetic state has more ACH and less dopamine
What are the five cardinal symptoms of parkinson’s disease?
Tremor - pill rolling
Rigidity - almost all patients
Bradykinesia - slowness in performing voluntary movement, reduced facial movement
hypokinesia - reduced ability to initiate movement/freezing
Postural instability/gait disorder - stooped flexed posture
What are the dopamine prodrugs used in parkinsons?
Levodopa (+carbidopa or benserazide)
When is parkinson’s therapy started?
When symptoms/functional disability becomes a problem for the patient
What is the first line therapy for parkinsons disease?
Levodopa (+carbidopa or benserazide) = choice in older people
Can start with dopamine agonist in younger patients w/ significant motor disability
Use anticholinergics if tremor predominates
How is levodopa used in parkinsons disease?
Used as first line - improves bradykinesia and rigidity
Need 75mg/day of benserazide or carbidopa to adequately inhibit peripheral dopamine production
Start low, gradual inc
What is a common ADR of levodopa and how is it treated?
Nausea - treat with domperidone (be mindful of QT prolongation)
What happens in levodopa is dosed too high or too low?
Too high = pt becomes dyskinetic - involuntary, writhing movement
Too low = akinetic - no movement/ can’t move muscles on own
What is the levodopa end dose effect?
When the pattern between the on (w/ dopamine) period becomes unpredictable with the pt experiencing off (when there is no dopamine) when they should be in an on period
How does the action of levodopa differ during advanced PD compared to early PD?
Advanced - inadequate symptom control, short duration of clinical result followed by an ON period where dyskinesia returns
Early - Sx control food, smooth and extended durations of movement, low dyskinesia
List some strategies that can be used to overcome the end of dose effect
Combine levodopa and dopamine agonist
Use modified release levo
Smaller more frequent doses of levodopa
adjust dietary protein
switch to dopamine agonists
Use COMT inhibitors (entacapone)
use rasagiline or selegiline
What is dyskinesia?
Difficulty performing voluntary movement
What is dystonia?
Involuntary muscle contractions - slow repetitive movements or abnormal posture
What are motor fluctuations?
Rapid (sometimes unpredictable) fluctuations of akinetic (off) and on (normal of dyskinetic) state
What is the role of dopamine agonists in parkinsons disease?
Less effective than levodopa as initial therapy - delay onset of dyskinesia and motor fluctations
improve bradykinesia and rigidity
Higher incidence of = confusion, impulse control disorders, hallucinations
