Parkinson’s disease

Definition:

• Parkinson’s Disease (PD) is a progressive neurodegenerative disorder characterized primarily by motor symptoms due to the loss of dopamine-producing cells in the substantia nigra, a region of the midbrain.

Epidemiology:

• Commonly affects individuals over 60 years of age.
• Slightly more prevalent in men than in women.

Pathophysiology:

• The hallmark pathological feature is the loss of dopaminergic neurons in the substantia nigra pars compacta and the presence of Lewy bodies (abnormal aggregates of protein that develop inside nerve cells).

Clinical Features:

• Motor Symptoms:
  • Bradykinesia (slowness of movement).
  • Resting tremor (‘pill-rolling’ tremor of the hands).
  • Rigidity (increased muscle tone).
  • Postural instability (impaired balance and coordination).
• Non-Motor Symptoms:
  • Cognitive impairment, mood disorders, sleep disturbances, autonomic dysfunction, sensory symptoms.

Diagnosis:

• Clinical diagnosis based on history and physical examination.
• Presence of two of the three cardinal signs (tremor, rigidity, bradykinesia) with a positive response to dopaminergic therapy strongly suggests PD.
• No specific laboratory or imaging tests, but these can be used to rule out other conditions.

Management:

• Pharmacological treatment:
  • Levodopa (often combined with carbidopa).
  • Dopamine agonists (e.g., pramipexole, ropinirole).
  • MAO-B inhibitors (e.g., selegiline, rasagiline).
  • Other medications for non-motor symptoms.
• Non-pharmacological:
  • Physical therapy, occupational therapy, and speech therapy.
  • Regular exercise.
  • Supportive therapies for mood, cognition, and sleep issues.

Prognosis:

• Progressive disease; while symptoms can be managed, there is currently no cure.
• Rate of progression varies among individuals.
• Focus is on maintaining quality of life and functional independence.