Parkinson's Disease Flashcards
From where does the basal ganglia receive input and where does it send output?
Input from cortex
Output to cortex and brainstem
What are the functions of the basal ganglia?
Help control motor movement, eye movements, social behaviour, executive function/working memory
What is the mean duration of Parkinson’s disease from diagnosis to death?
15 years
Describe the pathogenesis of Parkinson’s disease?
Loss of dopaminergic neurones within the substantial nigra with surviving neurons containing lewy bodies.
PD manifests clinically after loss fo ~50% of dopaminergic neurons
What are the possible causes of Lewy body formation?
Oxidative stress Mitochondrial failure Excitoxcitiy Protein aggregation Interface with DNA transcription NO Inflammation Apoptosis Trephine deficiency Infection
What are the cardinal features of Parkinsonism?
Bradykinesia
Muscular rigidity
4-6Hz rest tremor
Postural instability
What is bradykinesia?
Slowness in initiation of voluntary movement with progressive reduction in speech and amplitude of repetitive actions
What neuropsychiatric symptoms can occur in PD?
Dementia
Depression
Anxiety
What autonomic symptoms can occur in PD?
Constipation Urinary urgency / nocturia Erectile dysfunction Excessive salivation / sweating Postural hypotension
What sleep symptoms can occur in PD?
REM sleep behaviour disorder
Restless legs syndrome
Daytime somnolence
Other than the cardinal signs, neuropsychiatric, autonomic and sleep symptoms, what other symptoms can occur in PD?
Reduced olfactory function
Fatigue
Pain and sensory problems
Give examples of disorders with are commonly mistaken for PD?
Benign tremor disorders Dementia with Lewy bodies Vascular parkinsonism Parkinson plus disorders Drug induced Parkinsonism/tremor
Give examples of Parkinson plus disorders
Progressive supra nuclear palsy
Multiple system atrophy
If tremor is present in patients with an uncertain diagnosis of Parkinson’s disease what blood tests can be conducted to rule out other causes?
TFTs
Cooper
Caeruloplasmin
CT and MRI will appear normal in Parkinson’s disease but these investigations can be sued to rule out which conditions?
Vascular parkinonism
Parkinson plus disorders
What functional imaging technique can be used in the investigation of suspected Parkinson’s disease?
DAT SPECT
What four classes of drugs can be used to treat Parkinson’s disease?
L-DOPA
Dopamine agonists
MAO-B inhibitors
COMT inhibitors
Describe the action of L-DOPA
Taken up by dopaminergic neurons and decarboxylated to dopamine within presynaptic terminals
What drug is prescribed alongside L-DOPA to limit its systemic effects?
Dopa decarboxylase
What is the half life of L-DOPA?
90 mins
What dose of L-DOPA is given in Parkinson’s disease?
200-1000mg a day
What are the adverse effects of L-DOPA?
Nausea Vomiting Postural hypotension Confusion Hallucinations
Patients can develop motor complications after long term (5 years) L-DOPA treatment for Parkinson’s disease. T/F?
True
Give examples of dopamine agonists which can be used to treat Parkinson’s disease?
Ropinirole
Pramipexole
Rotigotine
Apomorphine
