Ask an Expert: Dr. Brenda Lau Discusses Pain in Parkinson’s

Dr. Brenda Lau, MD, is a pain specialist and anesthesiologist with over 20 years’ experience. She was a founder and board member of the Pain BC Society that formed in 2008. In 2011, she became the first chair of the Fraser Health Authority (FHA) region-wide pain services division. Two years later, she co-founded CHANGEpain Clinic, a Vancouver-based pain centre that provides multi-disciplinary care. She has led numerous national, provincial, and hospital-based initiatives to improve understanding of pain while improving treatments and care training. In 2015, Dr. Lau became the first Program Director of the Pain Medicine residency program at the University of British Columbia. Earlier this summer, Dr. Lau spoke at Parkinson Society BC’s June Symposium Series about pain in Parkinson’s disease (PD).

What causes pain in Parkinson’s disease?

There are many types of pain experienced by people with PD, including musculoskeletal (involving the soft tissue, bones, and joints), neuropathic (nerve pain, caused by pressure, compression, and narrowing of nerves), and central pain (pain signaling derived from the brain itself). Pain is the most common non-motor symptom experienced by people with PD, with research suggesting that approximately 68-83% of patients experience some degree of pain. However, just because a person has Parkinson’s does not mean they are guaranteed to experience any specific type of pain throughout the course of their illness.

Dystonia is the leading cause of pain affecting people with PD because of muscle rigidity, which can cause gait changes and muscle stiffness. A close second is neuropathic causes of pain, often caused by tight muscles. The nerves that pass through these muscles have trouble sending normal signals. Over time, due to repeated pain signals, the brain becomes more sensitive to pain not just at the originating site, but throughout the entire body. This can lead to a phenomenon called central sensitization, where pain becomes widespread and does not just follow one nerve root.

Pain is often aggravated by non-motor symptoms of PD, such as mood dysregulation, sleep issues, and autonomic dysfunction, which can vary widely between individuals. Risk factors for experiencing pain in PD — and which may impact the severity or nature of pain — include an early age of onset, long disease duration, motor complications, depressive symptoms, and other associated medical conditions. In advanced stages of Parkinson’s, people may experience pain if using high doses of medications like Levodopa, which may alter pain signaling.

How can care providers better treat pain?

When approaching a patient’s pain, it is important to look at it like the layers of an onion. Is the pain originating from the body level – is it coming from the skin, nerves, or muscles? Are movement patterns causing nerve compressions? Could there be any side effects from medications?

Pain services should be multi-dimensional to address the biopsychosocial issues. Medical therapy may include medication management, pain interventions, infusion therapy, and disease management. The interdisciplinary team should include allied healthcare professionals, such as movement specialists, physiotherapists, chiropractors, yoga coaches, kinesiologists/somatic therapists, exercise physiologists, psychologists, and pain coaches. Each of these professionals bring a different clinical perspective to a patient’s experience. Care providers must also take a holistic approach by examining factors such as relationships, relaxation, nutrition, mental health, movement, and sleep, and their respective impacts on pain.

What can carepartners do to help with pain?

Carepartners can support people with PD by being knowledgeable about pain, including pertinent resources from www.painbc.ca. In healthcare settings, carepartners can also be powerful advocates, helping to connect their loved ones with multidisciplinary pain teams, and other specialists who may best serve their needs. They can offer their support for the self-management and wellbeing of people with PD, such as by encouraging improved nutrition and sleep, meditation and self-care practices (such as mindfulness or box breathing), and time in nature.

What research is being done on pain in PD?

Repetitive Transcranial Magnetic Stimulation (rTMS), magnetic stimulation that alters brain neurotransmitters. This treatment has shown potential in treating rigidity. Other studies have found that it may help with upper limb bradykinesia (Lomarev et al., 2006). The benefit from rTMS for Parkinson’s may be derived from its inhibition of dopaminergic systems (Mi et al., 2020; Shimamoto et al., 2001). Normally, rTMS is a private-pay treatment option, but new university-based research studies are offering it at little to no cost.

Burst spinal cord stimulation, where electrodes like those in a pacemaker are placed in different parts of the brain or spinal cord. This may help change the signaling within muscles and, in some people, may help with rigidity. Recent studies have also found that newer methods of administering this therapy may improve pain, posture, and mood without the side effect of causing “pins and needles” sensations that could occur with older administration methods (Cai et al., 2020; Kobayashi et al., 2018).

The microbiome and the gut-brain connection, which have become prominent topics of interest in the last decade due to their impact on inflammation and the immune system. Research has also found that changes in the microbiome may influence the types of pain that people with PD experience (Rajoka et al., 2017; Romano et al., 2021).

How can people with PD self-manage their pain?

In BC, Group Medical Visits (GMVs) are ways for patients to access physician and specialist expertise in a group setting, and are funded under the Medical Services Plan (MSP). Due to increased time with the physician and the sharing of knowledge in a group setting, a wider breadth of topics are covered compared to the one-on-one physician appointment. At CHANGEpain clinic, their GMVs cover pain and pain-related topics involving sleep, energy, mood, trauma, post-traumatic stress disorder, anxiety, nutrition, gut health, and safe movement, as well as various other pain syndromes. They enable patients to understand their condition more holistically, empower patients with self-management tools, and are a source of community for individuals facing similar issues.

A healthy, balanced diet may also help people with PD better self-manage their pain due to the effect of nutrition on the microbiome. A diet rich in prebiotic fibre, B vitamins, antioxidants, Omega 3s, and minerals such as magnesium may also help to support gut health. Additionally, certain foods, such as fresh fruit and vegetables, nuts, seeds, and fish, have been found to slow the progression of Parkinson’s (Mischley et al., 2017). Studies so far strongly suggest that changes in gut health may impact neuroinflammation. Bacterial imbalances in the gut could influence PD patients’ disease course and response to medications like Levodopa. However, more research is required to assess gut-related therapies in Parkinson’s patients.

Can alternative therapies, like massage therapy, tai chi, and acupuncture, help pain in Parkinson’s?

These therapies certainly have the potential to help pain. However, it is hard to precisely quantify the benefit of any alternative therapy, as not enough research has yet been funded to study their effects.

If, after three to four months of consistently working with a therapy, a patient is not improving, or worsening, it is advisable to stop and reevaluate. If the therapy is helpful, it is the patient’s decision whether or not it is worth their time and money to continue. However, if the benefit is short-lived, questions should be asked about what else can be done to prolong that benefit. Can more be added to the treatment plan? For example, if a patient experiences a short-lived benefit from massage, can they better optimize their sleep or nutrition to extend this benefit?

How can you and your clinic help people with PD manage their pain?

CHANGEpain Clinic offers the breadth of evidence-based pain and function recovery services that apply the best science, knowledge, and technology from medicine, nutrition, brain health, and movement. The clinic offers many GMVs led by their multi-disciplinary team about various topics pertaining to pain, movement, and rehabilitation. They also offer a multitude of targeted treatments, which may assist people with PD in managing their pain or pain-related disabilities. MSP-covered therapies include medication management, ultrasound, and fluoro-guided pain procedures for muscles, ligaments, and joints (ie., procedures using continuous x-rays and other “video” imagery to study moving body parts). Private-pay therapies include infusion therapy for depression or nerve pain and Botox for headaches, as well as prolotherapy (targeted injection treatment) or regenerative therapies for joint problems. Extended healthcare, WorkSafeBC, and/or ICBC may cover other therapies, including physiotherapy, kinesiology, somatic therapy, psychology, chiropractic treatment, and pain coaching.

Sources

Cai, Y. et al. (2020). Spinal cord stimulation in PD. Bioelec. Med, 6(5). www.doi.org/10.1186/s42234-020-00041-9

Kobayashi, R. et al. (2018). New mode of burst spinal cord stimulation improved mental status as well as motor function... J PD, 57, 82-83. www.doi.org/10.1016/j.parkreldis.2018.07.002

Lomarev, M. P. et al. (2006). Placebo-controlled study of rTMS for the treatment of Parkinson’s disease. Mov. Dis., 21(3), 325-331. www.doi.org/10.1002/mds.20713

Mi, T. et al. (2020). Repetitive transcranial magnetic stimulation improves Parkinson's freezing of gait via normalizing brain connectivity. NPJ PD, 6(16). www.doi.org/10.1038/s41531-020-0118-0

Mischley L. K., et al. (2017). Role of diet and nutritional supplements in Parkinson's disease progression. J OMCL. www.doi.org/10.1155/2017/6405278

Rajoka, M. et al. (2017). Interaction between diet composition and gut microbiota and its impact on gastrointestinal tract health. J FSHW, 6(3), 121-130. www.doi.org/10.1016/j.fshw.2017.07.003

Romano, S. et al. (2021). Meta-analysis of the Parkinson’s disease gut microbiome suggests alterations linked to intestinal inflammation. NPJ PD, 7(27). www.doi.org/10.1038/s41531-021-00156-z

Shimamoto, H. et al. (2001). Therapeutic effect and mechanism of repetitive transcranial magnetic stimulation in Parkinson's disease. Neurol., 248, 48-51. www.doi.org/10.1007/PL00007826

This content was published in the Winter 2021 edition of our quarterly magazine, Viewpoints. The content was accurate as of this publication date.