In February, the Davis Phinney Foundation (DPF) hosted a session on managing pain in Parkinson’s disease (PD) with movement disorder specialist Dr. Jori Fleischer. Pain disorders are a common under-recognized non-motor symptom of PD. Dr. Fleischer discussed the different types of pain in PD and how to work with a doctor to manage pain. Dr. Fleischer noted that pain is often not discussed in the exam room: 40% of people don’t mention it to their doctor because they may not know it’s relevant to PD. This session was part of DPF’s Victory Summit virtual event.
Dr. Fleischer described pain as an unpleasant sensory and emotional experience associated with actual tissue injury or potential injury. Up to 90% of people with PD report pain at some point. Chronic pain is twice as common in people with PD than in people who don’t have PD.
Pain can occur at any stage in PD. In early PD, pain may be the most bothersome non-motor symptom, as there are changes in the nerve endings, spinal cord, and brainstem pathways that detect and regulate pain. In advanced PD, pain has been rated as the sixth most troubling symptom.
There are four different types of pain:
- Musculoskeletal: muscle cramps and tightness, joint pain
- Dystonic: spasms
- Neuropathic: nerve pain
- Central: poorly localized constant pain
There is now a PD pain questionnaire, available online. You could complete this questionnaire and take it to an appointment with a PD specialist. Note: the pain questionnaire is on page 20 of this research study PDF.
A healthcare professional will want to use the OLD CART framework for inquiring about pain. (See the notes below.)
Pain management in PD requires attention to timing, quality, and relation to medication doses. Dr. Fleischer suggested taking a customized multidisciplinary approach to pain management. This may include physical therapy, acupuncture, or medication therapy. Physical therapy and exercise are a crucial element to improve mobility, prevent contractures, and maintain range of motion. The speaker mentioned that there is no proven benefit for medical marijuana.
For more information on pain, please see this Stanford Parkinson’s Community Outreach webpage
For more information on complementary therapies and medical marijuana, please see this Stanford Parkinson’s Community Outreach webpage
For a recording of this session, please see this Davis Phinney Foundation YouTube webpage
See my notes below of the February 18th session.
Regards,
Joëlle Kuehn
“Managing pain in Parkinson’s” – Session Notes
Speaker: Jori Fleischer, MD, MSCE, neurologist, Rush Medical College, Chicago, Illinois
Session Host: Davis Phinney Foundation
Session Date: February 18, 2022
Summary by: Joëlle Kuehn, Stanford Parkinson’s Community Outreach
Pain: Unpleasant sensory and emotional experience associated with actual tissue injury or potential injury
Pain pathway:
- Starts in sight of injury
- Signal goes to spinal cord
- Sends signal to brainstem
- Moves to cerebrum
How pain works:
- Skin, joints, organs contain millions of nerve fibers whose job it is to detect injury of different kinds
- Some sensitive to heat, pressure, vibration, light tough, where things are in space
- Nerve fibers send information up to brain through different pathways
- Two systems:
- Affective system, or cognitive evaluative dimension of pain: links physical sensation of pain to an emotional response and also to memory
- Lateral system/sensory discriminative system: tells you where the pain is located and how long it lasts
- Both systems are receiving information at the same time and sorting it differently, sending it on to different way stations, but helping process what we label as pain
- Ex: a curious toddler touches electrical socket, when touch it:
- Nerve fibers in finger register electrical shock
- Send information in milliseconds up nerve to finger, to arm, to spinal cord, up through brainstem to medial and lateral pain system
- Lateral pain system quickly tells you that sensation is coming from finger, so you can take finger out and get it out of harm’s way
- Medial system (if toddler and this is new) might first register emotion of surprise, and then connect that sensation to unhappiness or fear and lead you to cry
- Will also link sensation, so “finger + socket = pain” and “pain = not good” and will store that as a memory for the future
- Everything is connected
How common is pain in PD:
- Very common
- Even Dr. Parkinson recognized it
- Depending on pain type, up to 90% of people with PD report pain at some point
- Chronic pain is twice as common in PD than in people who don’t have it
- Often not discussed:
- 40% of people who have pain don’t mention it to their doctor
- May not know it’s relevant to PD
- Studies show pain results in worse quality of life regardless of any other symptoms
When do people experience pain in PD:
- In early PD, pain may be the most bothersome non-motor symptom
- In advanced PD, pain was rated as 6th most troubling symptom
- Even early in PD, there are changes in the nerve endings, spinal cord and brainstem pathways that detect and regulate pain
4 types of pain in PD
Musculoskeletal pain:
- We have all felt this at some point. Ex. if you walk for a long time, long bike ride, hit the gym hard
- 45-75% prevalence
- In PD, problems in muscles or bones/skeleton usually related to rigidity and decreased movement, and sometimes arthritis
- If you aren’t moving, you will lose the ability to move:
- The less you move, the more stiff you get, the more painful muscles can be
- Similar for joints and muscles in PD
- Muscle cramps and tightness:
- Most often neck, arm, paraspinal, calf muscles
- May be present for years before PD is diagnosed
- Very common symptom in PD early on
- Joint pain:
- Most often in shoulder, hip, knee, ankle
- Often unilateral shoulder pain with limited range of motion
- One-side shoulder stiffness/pain is very common in PD
- Often thought to be from sports, etc. and sent to physical therapy, injections, surgery, etc. but in actuality it’s stiffness from PD
- Surgery won’t fix it, but treating PD will
- May be a presenting symptom. May be a symptom that gets them to medical care to get a diagnosis of PD
Dystonic pain:
- 8-50% prevalence
- Dystonia: muscles fighting against each other: one is contracting and pulling the limb, and the other muscle or muscle group is pulling in a different direction. Leads to strange twisting of muscles that are involuntary
- Repetitive, patterned postures of dystonia can cause severe, painful spasms of extremities, face, and pharyngeal muscles
- Paroxysmal; so can be spontaneous or triggered by movement
- Can occur early in PD unrelated to medications
- Can occur later in PD associated with medications
- Could be feet, or toes cramped
- Foot dystonia:
- Plantar flexion and foot inversion
- May occur early and as presenting symptom, particularly early-onset cases, Parkin cases (a genetic form of PD)
- Dystonias are more often a complication of treatment:
- Early morning OFF-dystonia in 15%, symptom of dopaminergic deficiency. Related to medication, when you are at your lowest dopamine during the day
- Diphasic, peak dose dystonia (most often in neck and face)
- Can be painful or also not painful
Radicular/neuropathic pain:
- 5-20% prevalence
- Nerve getting crushed. Disc in spinal cord, as we age gets stiff outside and liquid inside can leak and push onto nerve and spinal cord, arthritis makes nerve tunnel tighter
- Pain shoots down leg into foot
- Nerve pain, sharp, shooting electrical pain. Ex. bumping your funny bone is a similar pain
- Distribution of one nerve or nerve root
- Excludes other causes. Not always PD
- Neurological, electrophysiological and imaging tests may be needed
- May be due to postural abnormalities or dystonia, discopathy, radiculopathy or mononeuropathy
Central pain:
- 10-12% prevalence
- Poorly localized, vague character, constant pain:
- “I just hurt, everything just hurts. It’s all over and nowhere all at once”
- Hard to say what it is but it is just pain
- We know in brain where sensation is coming from, but finding how to treat it can be tricky
- Not localized to a nerve distribution:
- May have autonomic/visceral character in some people with PD, with reports of abdominal pain or reflux, dyspnea, or feeling flushed
- May have oral, genetal, or rectal pain
Talking with your health care provider about pain: How to take a history – OLD CART
- O: onset – when did it start?
- L: location – where is it?
- D: duration – how long has it been going on? Does it come and go? When there, how long does it last?
- C: character
- A: aggravating and alleviating factors – what makes it better, what makes it worse?
- R: radiation
- T: timing
How to prepare for doctor:
- There is now a PD pain questionnaire – can find online, could print off and check off and bring to your next PD specialist appointment
- Write it down. Not just pain but any fluctuations.
- Write down as much OLD CART as you can, or notes on meds, pain, symptoms throughout the day, dyskinesias, drop in blood pressure
- Keep diary three days before your visit/ Doesn’t have to be super detailed but try to do as much detail as you can
- When you actually took medication, even if supposed to do it at 8, write down the actual time – be honest
- Honesty is best policy, doctor should not be giving you a hard time, if they are, find another doctor
- If you aren’t honest and doctor alters treatment or dosage based on that, it will have harmful effects
Management of pain in PD:
- No one size fits all approach to pain in PD
- Need a multidisciplinary approach across the PD spectrum
- Exercise, physical therapy are very important. To maintain range of motion, prevent falls, fractures, and contractures
- Interdisciplinary palliative interventions have demonstrated that pain is both common and treatable. In early and later PD
- Only 3 drugs have been studied for pain in PD in rigorous randomized controlled trials, and they failed
Pain management
Musculoskeletal pain management:
- Usually physical therapy, +/- medications. Physical therapy will be first and most important
- Heat/ice, massage, gentle stretching, topical OTC therapies
- If pain is due mostly to rigidity or bradykinesia: dopaminergic therapy may help
- Levodopa, dopamine agonists
- Therapies to extend duration of dopaminergics, including COMT inhibitors (ex. entacapone) and MAO-B inhibitors (ex. rasagiline)
- Safinamide shows possible improvement in use of pain medicine
- If rheumatologic (i.e. rheumatoid arthritis) or orthopedic: nonsteroidal anti-inflammatory drugs (such as ibuprofen or naproxen) or other analgesics
- Orthopedic joint surgery if significant joint injuries
Radicular/neuropathic pain management:
- Avoidance of overuse (ex. of same position) or poor posture – physical therapy and occupational therapy
- May require surgery to remove the disc pressing on the nerve
- Many medication options, a combination may be most effective:
- Low-dose antidepressants, including tricyclic antidepressants (ex. nortriptyline) and selective serotonin-norepinephrine reuptake inhibitors (ex. duloxetine)
- Antiepileptics (ex. gabapentin, pregabalin)
- Non-steroidal anti-inflammatory drugs (ex. ibuprofen)
- Opioid analgesics (ex. morphine, codeine)
Dystonic pain management:
- See where pain is in relation to you taking your medication
- Manipulation of dopaminergic medications
- Adjustment of dosage, dose times, switching to longer acting preparations to reduce dopamine pulsatility. Rotigotine: improved fluctuation-related and early morning pain in two studies
- Evaluating and manipulating dietary protein
- Amantadine for peak-dose dyskinesias
- Botulinum toxin injections for focal dystonia (striatal toes, dystonic fists). Difficult balance between symptom relief and preserved function
- Deep brain stimulation (DBS) to the subthalamic nucleus (STN) and GPi has shown improvement of dystonia and dystonic pain
Central pain management:
- Dopaminergic therapy
- Anti-inflammatory agents
- Antiepileptics (ex. carbamazepine, gabapentin)
- Antidepressants (ex. tricyclic antidepressants such as nortriptyline)
- Opiates (ex. morphine, codeine)
- Atypical neuroleptics (ex. clozapine)
Other contributors to pain that need to be addressed:
- Depression:
- People with chronic pain are more likely to be depressed
- People who are depressed are more likely to have chronic pain than people who are not depressed
- People with PD are more likely to be depressed regardless of pain than people without PD because there are changes in those pathways as well
- People who are depressed have a hard time sticking to their medication regimens, often don’t tell loved ones if missed dose or stopped
- Diabetes
- Osteoporosis
- Rheumatologic disease (ex. rheumatoid arthritis, psoriatic arthritis, polymyalgia rheumatica)
Deep brain stimulation (DBS):
- Has been studied in relation to pain in multiple studies. Most studies, primarily subthalamic nucleus DBS, show improvement in pain symptoms with stimulation
- DBS may help with pain in some people
Alternative treatments:
- At least 40% of people with PD use one of these in addition to standard western medical treatments
- May not be studied to scientific western standards, so doctors may be reluctant to suggest
- Hard to endorse if don’t have all the data, but that doesn’t mean it doesn’t work
- May still be waiting for more information
- Acupuncture:
- Helpful in other pain conditions
- Few side effects
(Alternative treatment) Medical marijuana:
- Aspirin is one chemical – we know a lot about aspirin
- Marijuana contains at least 60 active chemicals. May not know as much about them
- They include:
- THC (tetrahydrocannabinol): has psychoactive effects, can cause hallucinations
- CBD (cannabidiol): potential therapeutic effects
- Receptors for cannabinoids exist throughout the nervous system, especially in basal ganglia, and have many different effects
- Many surveys in medical marijuana in PD
- Survey of 339 people with PD in Czech republic:
- 25% reported using marijuana (not medically), 46% of those people with PD described some benefit in either tremor, bradykinesia or levodopa-induced dyskinesias
- 339 people sounds like a great large amount
- Problem: only 54% of those people actually completed survey
- 183 people completed survey
- 46 people said that they used marijuana, 21 said it helped
- Those actual numbers seem quite different than what is reported
- It’s important to not just look at the headlines, and also look at the data
- Small, open-label study (people knew what they were getting, no placebo:
- 22 people with PD
- Subjective improvement in tremor, stiffness, pain and sleep
- 4 controlled clinical studies found NO benefit for motor symptoms and mixed results for dyskinesias and quality of life
- The most rigorous study of medical marijuana in PD was for levodopa-induced dyskinesias in 19 people with PD: insignificant worsening of dyskinesias
- Side effects of medical marijuana: low blood pressure, dizziness, hallucinations, sleepiness, confusion
- Bottom line:
- Current research suggests that cannabinoids are probably ineffective for both levodopa-induced dyskinesias and motor symptoms
- Further rigorous study of different doses, formulations, and target symptoms may reveal specific differences
Question & Answer Session:
Question: Does mindfulness practice actually reduce pain or just allow one to tolerate it?
Answer: I don’t know if we know, and I don’t know if we know that those things are separate because pain is multifactorial and there is an emotional component.
Question: Are there any apps or digital ways to create a pain diary?
Answer: I know there are apps to track symptoms. There is a popular one called Health Empower for PD symptoms but I don’t know if it has specific pain questions there.
Question: Could severe neuropathy in the feet be an early symptom of PD?
Answer: There is a lot of conflicting evidence if you have neuropathy that starts in both feet and works its way up. There is evidence that this may be part of PD, but it’s not known if it’s PD itself or the treatments or something else like a vitamin deficiency. Having it as a presented early system makes me worry that there is something else. I’d like to go through a regular neuropathy workup.
Question: Why does uncomfortable restlessness happen in sleep and is there something that can be done about that?
Answer: That sounds like it could be restless leg syndrome which is really common in PD. It’s not necessarily pain but pain is subjective. We want to make sure someone isn’t iron deficient because that is a common trigger for restless leg syndrome. Iron deficiency in an adult may also be a sign of blood loss, and there could be some other reason for that.
Question: I can’t take iron if I’m on levodopa, how do I fix a possible iron deficiency?
Answer: Don’t take them at the same time, but you can take them separately.