Parkinson's disease

Overview

Parkinson's disease is a progressive neurodegenerative disease in which dopamine-producing cells in the area of the brain that controls movement (substantia nigra) gradually die. It affects 1-2% of people over age 65; there are approximately 200,000 patients in our country.

There is no definitive treatment; however, with medications and other treatments, symptoms can be largely controlled.

Symptoms

Usually over age 60, slowly progressive. Symptoms start unilaterally and spread over time.

Motor symptoms (TRAP):

• Tremor (shaking): At rest, usually one hand at start
• Rigidity (stiffness): Muscle stiffness, difficulty with movements
• Akinesia/bradykinesia: Slow movement, difficulty moving
• Postural instability: Balance disorder, fall risk

Other motor:

• Decreased facial expression (masked face)
• Small handwriting (micrographia)
• Voice softening, lowering
• Swallowing difficulty
• Drooling
• Small steps, shuffling gait
• "Freezing" (inability to move suddenly while walking)
• Stooped posture

Non-motor (often before motor symptoms):

• Loss of smell
• Constipation
• REM sleep behavior disorder (acting out dreams)
• Depression, anxiety
• Cognitive problems, later dementia
• Urinary problems
• Low blood pressure (on standing up)
• Erectile dysfunction
• Extreme fatigue
• Skin problems (seborrheic dermatitis)
• Apathy
• Hallucinations (in advanced stages)

Stages (Hoehn and Yahr)

• Stage 1: Unilateral symptoms
• Stage 2: Bilateral, balance preserved
• Stage 3: Mild balance disorder
• Stage 4: Severe, walking with help
• Stage 5: Bedridden or wheelchair-dependent

Causes

The exact cause is unknown. A combination of genetic and environmental factors:

Genetic:

• Gene mutations such as SNCA, LRRK2, PARKIN, PINK1
• Family history increases risk (15%)

Environmental:

• Pesticide, herbicide exposure
• Some heavy metals
• History of head trauma
• Rural life, well water

Risk Factors

• Age (over 60)
• Being male (1.5 times more common)
• Family history
• Agricultural occupational exposure
• Head trauma
• Genetic mutations

Protective factors (observational):

• Caffeine consumption
• Smoking (debated)
• Regular exercise
• NSAID use (limited evidence)

Complications

• Falls, fractures
• Aspiration pneumonia due to swallowing difficulty
• Malnutrition
• Sleep disturbances
• Cognitive decline, dementia (Parkinson's disease dementia)
• Depression
• Psychosis (drug side effect or disease)
• Drug side effects (dyskinesia)
• Loss of independence
• Social isolation

When to See a Doctor

• Tremor at rest
• Slowing of movements
• Smaller handwriting
• Gait changes
• Decreased facial expression
• Voice changes
• Unexplained balance problems, falls
• Changes noticed by family

Diagnosis and Treatment

Diagnosis:

• Clinical examination (neurology)
• Detailed history
• UPDRS score
• Levodopa response (supports diagnosis)
• DAT-SPECT (dopamine transporter imaging)
• MRI (differential diagnosis)
• Blood tests (differential diagnosis)

Treatment:

1. Medication:

Levodopa (gold standard):

• Most effective drug
• Combined with carbidopa or benserazide
• Side effects: dyskinesia (long-term), nausea, blood pressure drop
• Effect "wears off" over time (motor fluctuations)

Dopamine agonists:

• Pramipexole, ropinirole, rotigotine
• First choice in young patients
• Side effects: compulsive behaviors (gambling, shopping), sleep attacks

MAO-B inhibitors:

• Selegiline, rasagiline, safinamide

COMT inhibitors:

• Entacapone, opicapone
• Prolong levodopa effect

Amantadine:

• For dyskinesia

Anticholinergics:

• Only if tremor-dominant, in younger patients
• Many side effects

2. Surgery:

• Deep Brain Stimulation (DBS):
  • In advanced patients
  • Electrode into subthalamic nucleus or GPi
  • Can provide significant benefit
• Focused ultrasound

3. Pump treatments:

• Levodopa intestinal gel pump (Duodopa)
• Apomorphine pump

4. Rehabilitation:

• Physiotherapy (gait, balance)
• Speech therapy (LSVT-LOUD)
• Occupational therapy
• Exercise (boxing, tai chi, yoga - proven benefit)

5. Treatment of accompanying conditions:

• Depression: SSRIs, SNRIs
• Sleep disturbances
• Constipation
• Hallucinations: pimavanserin, quetiapine

Lifestyle and Prevention

Prevention:

There is no definitive prevention method; however:

• Regular exercise (strongest protective factor)
• Healthy nutrition
• Avoid head trauma
• Avoid toxin exposure
• Adequate vitamin D, omega-3
• Coffee consumption (moderate)
• Manage stress

Lifestyle (after diagnosis):

• Regular exercise (very important, slows disease progression)
• Mediterranean-style diet
• Adequate protein (adjusted with levodopa timing)
• Plenty of water
• High-fiber foods (prevent constipation)
• Swallowing exercises
• Fall prevention: anti-slip carpets, grab bars
• Take medications regularly
• Family and social support
• Join Parkinson's patient groups
• Professional follow-up (neurology, physiotherapy)