Parkinson’s disease (spring) Flashcards
what is Parkinson’s disease?
a common and complex neurological disorder, affecting mainly movement
a neurodegenerative movement disorder caused by loss of dopaminergic neurons, primarily in the substantia nigra
why is there an increase in lifespan in people with Parkinson’s?
increased life expectancy due to health improvements in the young population e.g. childhood immunisation and the older population e.g. heart disease treatment
list the motor symptoms of Parkinson’s
Bradykinesia (slowed movement):
- Slowness of walking and other movements
- Reduced armswing or stride length
- Reduced facial reaction (“masked face”
- Softer or slurred speech
- Smaller handwriting
Muscular rigidity
- Stiffness of limb(s)
- Sometimes associated with pain
Rest Tremor
- Tremor in one limb with the limb at rest
- Tremor with holding a posture or with action
- asymmetric
Imbalance
- Loss of balance reflexes
list the non-motor symptoms of Parkinson’s
Autonomic dysfunction:
- Orthostatic hypotension
- Urogenital dysfunction
- Constipation
- Heat or cold intolerance
Sleep disorders:
- Sleep fragmentation
- Insomnia
- REM sleep behaviour disorder (RBD)
- Sleep attacks
Neuropsychiatric disorders:
- Fatigue
- Anhedonia
- Depression and anxiety
- Dementia
Sensory disorders:
- Pain
- Colourvision deficits
- Abnormal sensation
describe the clinical symptoms and time course of Parkinson’s disease progression
what is the role of dopamine?
dopamine is critical for the control of movement and acts as a neurotransmitter in the substantia nigra
causes of Parkinson’s disease
unknown cause in most cases (idiopathic or sporadic disease)
Specific environmental triggers
- some toxins, pesticide exposure, MPTP exposure
- Parkinsonism is also associated with exposure to influenza and repeated head trauma
Genetic component
- Inherited forms of Parkinson’s disease
- Genetic susceptibility in sporadic Parkinson’s disease
Pharmacological and Non-Pharmacological Treatment of parkinsons
Pharmacological Treatment
- Disease modifying therapies
- Existing therapies for PD are exclusively symptomatic
Non-Pharmacological Treatment
- Surgical interventions
give the pathway for dopamine treatment
L-DOPA is ~90% converted by DDC in the intestinal wall
Given with peripherally-acting DDC inhibitors, carbidopa or benserazide
L-DOPA also ~5% metabolised by plasma Catechol O-Methyl Transferase COMT inhibitor, entacapone, may be used as adjunct
Ensure majority of L-DOPA enters brain unchanged for conversion to DA
give dopamine pathway treatments
L-DOPA the first drug used and most effective at symptom relief
Common preparations:
- carbidopa/levodopa (co-careldopa) (e.g. Sinemet, Parcopa, duodopa)
- benserazide/levodopa (co-beneldopa) (e.g. Madopar)
- carbidopa, levodopa and entacapone (Stalevo)
Dopamine agonist (e.g. pramipexole) are also approved and in clinical use
dopamine pathway side effects
Acute = psychosis
Chronic = excess movements (dyskinesia)
what is stem cell therapy for Parkinson’s?
Replacement of cells in the basal ganglia to correct the underlying cause of lowered dopamine levels
