Chapter 21: the Parkinson's disease spectrum Flashcards
Parkinson’s disease
Is a chronic disease and has a progressive nature where symptoms worsen over time and new symptoms may arise. It cannot be prevented, cured or its progression delayed, only symptomatic treatment is available. More men than women have the disease and it’s onset is between 50 and 70. Industrialization and pollution of the environment are also associated with the development of Parkinson’s disease. Non-smoking, non-caffeine consumption and adequate exercise are protective factors against the disease.
Motor symptoms of Parkinsons
- Bradykinesia: slowing of movement.
- Akinesia: difficulty starting movements.
- Hypokinesia: lack of automatic movements (can lead to drooling or reduced facial expressions.)
- Rigity: stiffness of the muscles.
- Micrographia: small writing
- Resting tremor: the skaing or trembling of a limb at rest.
- Postural instability: inability to balance due to loss of postural reflexes.
Types of Parkinson’s:
- Tremor-dominant type
- Postural instability and gait difficulty (PIGD) type: associated with a more progressive course, faster cognitive decline and more frequent occurrence of depressive symptoms.
Movement Disorder Society-Unified Parkinsons Disease rating scale
Consists of 4 parts:
1. non-motor experiences of daily living
2. motor experiences of daily living
3. motor examination
4. motor complaints
The Hoehn and Yahr scale can be used in addition:
1. Unilateral involvement only
1.5 Unilateral and axial movement
2. Bilateral movement without impaired balance
2.5 Mild bilateral disease
3. Mild to moderate bilateral disease, but physically independent
4. severe disability, but still able to walk or stand
5. wheelchar-bound or bed-ridden unless assisted
Non-motor symptoms
- Sensory symptoms: pain, olfactory (reuk) impairment, visual impairment.
- Sleep disturbances: insomnia, daytime sleepiness, REM-sleep behavioural disorder (dream-enactment behaviour).
- Autonomic symptoms: constipation, bladder problems, weight loss etc.
- Neuropsychiatric disorders: depression, anxiety, impulse control, apathy etc.
- Cognitive impairment: will result in dementia.
- Fatigue: 50% of the patient experience this.
Parkinson’s in the brain
Caused by a degeneration of dopamin-producing neurons in the substantia nigra. This is part of the ganglia-thalamo-cortical circuit, which regulates motor, cognitive and behavioural processes.
Diagnosis of Parkinsons
A diagnosis can be made when not only the non-motor symptoms are aparent, but also the motor symptoms like bradykinesia with either tremor or rigity. An MRI can rule out other causes, while the PET or SPECT investigates the presence of dopaminergic deficiency.
Parkinsonism
A diagnosis of Parkinsonism will be considered when the motor symptoms do not improve slightly after the use of Parkinson’s medication.
MSA (multiple system atrophy)
An early autonomic disorder, combined with severe speech and swallowing, cold and blue discolored hands and feet, impaired trunk balance and severely stooped posture, which makes people quickly wheelchair bound.
PSP (progressive supranuclear paralysis)
More upright or even slightly stretched backwards posture. Shows disturbances in eye movements, disinhibition and emotional instability.
CBD (corticobasal degeneration)
Heterogenous and hard to diagnose, but some symptoms can be persistent muscle contraction and difficulty controlling a limb (alien limb syndrome).
Lewy body dementia (DLB)
Prominent cognitive impairment and neuropsychiatric symptoms that even arise before motor symptoms.
Medicational treatment
Medication can be used to target the dopaminergic system in the brain, like levodopa. However, the medication can cause nausea, daytime sleepiness, hallucinations and impulse control disorders. In the long-term the medication can last for a shorter period or take longer before it becomes effective.
LCIG (levodopa-cardiodopa intestinal gel)
A gel that causes more continuous dopaminergic stimulation, which leads to more constant levodopa levels.
Deep brain stimulation
Implanting a thin wire with electrodes within the subthalamic nucleus. The electrode is connected to a stimulator that is placed under the skin and can alter the abnormal signals in the brain, which leads to improvement in motor and non-motor symptoms.