Parkinson's Disease: An Overview

• Parkinson's disease (PD) is expected to more than double by 2040, becoming the fastest growing neurologic disorder globally.

Geographic, Incidence, and Prevalence

• 9.4 million people are estimated to be living with PD globally in 2020
• Prevalence is projected to more than double by 2040
• PD is one of the leading causes of disability globally
• The vast majority of PD cases are idiopathic
• 10-15% of PD cases have a genetic disposition, often from a mutation of the LRRK2 gene
• Environmental factors like heavy metals, repeated head injury, and some herbicides/pesticides can contribute to development of PD
• A Parkinson's Foundation study confirmed that men are more likely to develop PD than women, and that the number of people diagnosed with PD increases with age, regardless of sex

Diagnosis and Progression

• PD diagnosis can only truly be determined at autopsy, as there is no specific test
• A clinical exam and presentation can help diagnose, with an asymmetry of onset and a resting tremor of 4-5Hz and variable amplitude
• A good response to dopaminergic therapy also is indicative of PD
• Meaningful (>50%) improvement in symptoms in response to medication further supports the diagnosis
• Neuroimaging, including CT and MRI, is often unrevealing, but is used to rule out other possible diagnoses
• Two studies found that 25% of patients diagnosed with PD by neurologists actually had other diagnoses found at autopsy
• Conditions often confused with PD include striatonigral degeneration, progressive supranuclear palsy, multi-infarct dementia, and Alzheimer’s
• KNOW THE DIFFERENCE
• During the first 5 years of PD, dopamine is produced but at decreased levels
• Available dopamine decreases during the 5-20 year stage.
• After 20 years, there is no dopamine

Symptoms and scales

• Early symptoms include micrographic hand writing, decreased speech volume, decreased facial expression, unilateral symptoms.
• Late symptoms include bilateral involvement, festination, freezin, retropultion, dyskinesia, swallowing difficulties.
• There is tremendous variability among people with PD which can be quantified using Hoehn and Yahr Stages
• Vision deficits are associated with PSP especially downward gaze
• Cerebellar symptoms are associated with MSA as well as urinary symptoms (up to 96%!) and greater dysautonomia (OH, supine HTN)
• REM behavior disorder and sleep disturbance is associated with MSA
• Loss of function on 1 side of body is associated with CBGD as well as jerky limb movements and speech/swallowing deficits
• Vision and personality changes occur with PSP
• PSP and CBGD can cause bulbar rigidity, swallowing deficits, rapid progression, and poor medication response
• Fatigue is common and can start early
• Three scales for fatigue are recommended for screening: FSS, FACIT-F, PFS
• Screen for sleep disorders and educate on sleep hygiene
• Blunted HR and BP response to acute exercise which can lead to increased fatigue, reduced blood flow to the brain, and syncope
• New videos on Oh can be found on Youtube on ANPT

Other relevant signs and symptoms

• Neurogenic OH signs are: Supine HTN relative to sitting, Minimal HR response to postural change
• Non-neurogenic OH HR Increased > 15 bpm with postural change (10-20 bpm is normal for standing)
• Inadequate HR increases in hypertension during exercise
• Exercise training may improve cardiovascular autonomic function in PD (evidence is limited)
• Deep brain stimulation surgery is used when patients have increased "off" time or excessive dyskinesia
• DBS does not usually improve postural instability or walking problems, or the their non-motor symptoms
• Before performing a physical therapy exam with PD patients, determining ‘on’ or ‘off’ state is essential
• During PT examination be sure to review referral information including reason and history

PT Considerations

• PT Subjective must include symptoms observed and reported include meds and schedule, symptom fluctuations.
• PT must understand symptoms/mobility in different environments
• Fall frequency matters, include all near misses.
• Ask about ADLs, speech, and swallowing include musculoskeletal and cognitive
• Exercise doesn't improve fatigue
• Ask about ADL, speech, and swallowing impairments
• Patient should identify if they experience OH

Fall history

• Tremor, Bradykinesia, Rigidity are not generally modifiable by PT
• Posture = "Classic"
• Balance with cognitive tasking
• Size and speed of movement; note arrests in movement Fixed vs flexible Postural complaints are common

Outcome Measures

• Mini Bestest and Berg, both measure core strength, note the differences and use as clinically relevant
• Mini-BESTest is more responsive to change and is more accurate that Berg in predicting falls
• If someone is too low functioning to do the MiniBEST (ie. unlikely to show change over time) will do a Berg
• A gait speed of 0.88 m/sec correctly predicts 70% of community walkers
• Minimal Detectable Change in mild/mod PD, Comfortable speed=0.09 m/sec, Fast speed=0.13 m/sec
• 5 X Sit to Stand has good MDC at 4.2 sec and TUG 11 sec for senile

PD Specific Measures

• Movement Disorders Society Unified Parkinson Disease Rating Scale helps assess PT and tells your about deficits.
• Need to know how to interpret and when test was given
• The new Freezing Of Gait Questionnaire measures FOG severity focuses on freezing and has scores 0-28
• If FOG is apparent you can administer it
• The Parkinson’s Questionnaire-39 assesses QOL and includes, higher scores are worse. Good for participation review

Interventions

• Neuro muscular includes hypokinesia and MS Is physical therapy intervention recently published with European guideline and details?
• External cueing reduce motor skill, external training
• Key is Balance Training
• A combination is key as well as telerehabilation
• You'll want to start cardio on the treadmill at minimal impact and frequency
• Strength is recommended to improve several symptoms

Cardio

• Magnitude matters most at 60 to 85 percent max, 3 times a week
• High-intensity cycling may aid with endurance and improve motor control processes
• Balance can reduce motor
• It can occur rapidly over time
• The balance will need challenged with supervision

Strength Training

• There are several ways to measure, progress to achieve gains and avoid pain
• Mobility changes requires testing every session, ascent/decent with mobility Balance requires cueing with supervision
• The goal= External Cues
• The type does not matter: auditiory vs visual vs sense
• Big movement for large steps and focus mostly in mild progression

Balance and Gait

• Best tested with bestest tests and more complex
• The body has limited evidence
• Best way to assess with multiple balance test
• No superior mode and harness must be used
• Gait has lots of components
• Dual Task must tested at the same time as cognition and motor
• Multi model testing better than multi testing
• Physical therapsit would reduce motor skills and improve QOL with these options
• Flexibilty can improves range
• All will need help to decrease bad habits by doing things
• This can only be addressed if you provide them safety and feedback -You may need patients on and off meds for stability assessment
• Always ask what has improved overall with these treatments