Parkinson’s disease is a progressive neurodegenerative disorder affecting movement.
It is caused by the degeneration of dopamine-producing neurons in the substantia nigra, a part of the brain that controls movement.
Causes
Genetic Factors: Mutations in specific genes (e.g., LRRK2, PARK2).
Environmental Factors: Exposure to toxins like pesticides and heavy metals.
Age: Incidence increases with age.
Gender: More common in men than in women.
Symptoms
1) Motor Symptoms
Tremor: Shaking, often starting in one hand.
Bradykinesia: Slowness of movement.
Rigidity: Stiffness in limbs and trunk.
Postural Instability: Impaired balance and coordination.
2) Non-Motor Symptoms
Cognitive impairment and dementia.
Mood disorders: Depression and anxiety.
Sleep disturbances: Insomnia, REM sleep behavior disorder.
Autonomic dysfunction: Constipation, orthostatic hypotension, and urinary problems.
Diagnosis
Clinical Evaluation: Based on medical history and neurological examination.
Imaging Tests: MRI or DaTscan (dopamine transporter scan) to support the diagnosis.
Response to Medication: Improvement of symptoms with dopaminergic medications supports the diagnosis.
Pathophysiology of Parkinson’s Disease
Dopamine Deficiency: Degeneration of dopaminergic neurons in the substantia nigra of the brain.
Lewy Bodies: Abnormal aggregates of the protein alpha-synuclein inside neurons.
Basal Ganglia Dysfunction: Impaired regulation of motor activity leading to symptoms like bradykinesia, tremors, and rigidity.
Treatment
1) Medications
Levodopa: The most effective treatment, often combined with carbidopa.
Dopamine Agonists: Mimic dopamine effects (e.g., pramipexole, ropinirole).
MAO-B Inhibitors: Prevent breakdown of brain dopamine (e.g., selegiline, rasagiline).
COMT Inhibitors: Prolong the effect of levodopa (e.g., entacapone).
2) Surgical Treatment
Deep brain stimulation (DBS) for patients with advanced symptoms not controlled by medication.
3) Physical Therapy
To improve mobility, balance, and flexibility.
4) Occupational Therapy
To assist with daily living activities.
5) Speech Therapy
To address speech and swallowing difficulties.
