Parkinson's Disease

Question 1

Determinants of Parkinson’s Disease

Answer 1

• history of NOT drinking alcohol
• history of NOT drinking coffee
• history of NOT smoking
• Exposure to toxins and pesticides
• Existing health conditions - DIABETES and DEPRESSION
• increasing age
• daytime sleepiness (somnolence)
• previous head trauma or epilepsy
• Family history - PD or DEMENTIA

Question 2

Pathophysiology of Parkinson’s Disease

Answer 2

Degradation of substantia nigra –> loss of dopamine
–> effects direct and indirect pathways of basal ganglia –> more inhibition –> less movement

Disrupts output from basal ganglia to thalamus

Question 3

Clinical Feats. of Parkinson’s Disease

-With explanations

Answer 3

1. TREMOR
2. RIGIDITY- muscle tone increases (muscle is resistant to being lengthened due to:
   a) being overactivated by CNS
   b) muscle being shortened overtime
   REGARDLESS of how fast muscle is being lengthened
3. AKINESIA- freezing of movement due to not being able to prepare for whole movement

(Bradykinesia = slowness of movement due to slowly switching between movement sequences)

(Hypokinesia = reduced movement due to decreased automatic movement with each submovement)

4. POSTURAL INSTABILITY - stooped, abnormal reflexes (due to stiffness -affects posture and balance or decreased motor preparedness)
5. FACIAL EXPRESSIONS - expressionless (due to slower muscles)

Question 4

Progression of Parkinson’s Disease

Answer 4

• Without medication, symptoms get worse
• With medication, Leva-dopa (form of dopamine) substitutes the lost dopamine –> symptoms improve
• Overtime, substantia nigra continues to degenerate until Leva-dopa levels can’t provide effects anymore –> symptoms get worse