Pain in Parkinson’s Disease
Pain is one of the most disabling non-motor symptoms of Parkinson's disease, affecting up to 80% of sufferers. The origin of pain symptoms in the disease has yet to be fully understood.
Does chronic pain have a peripheral origin? A central origin? Is the onset of chronic pain in Parkinson's disease affected by sensory, cognitive, and/or affective vulnerability? Is it possible that people with Parkinson's disease have abnormally low pain thresholds and/or that the brain has difficulty modulating pain?
There is very little data on this subject.
The aim of our research projects is to help elucidate the origin of pain in Parkinson's disease by establishing the sensory profiles of people suffering of Parkinson's Disease with and without chronic pain, during sessions with and without the first levodopa (dopamine precursor) medication.
People with Parkinson's disease are currently being evaluated using pain sensitivity and modulation tests, and neuropsychiatric questionnaires. To compare results and try to understand what is specific to Parkinson's disease and what is specific to chronic pain, participants with chronic pain but without Parkinson’s Disease and healthy participants are also in recruitment.
Insterested in participating in our projects? Click here for more information.
Our projects are funded by a grant from the Canadian Foundation for Innovation and by a pilot project grant from Parkinson Canada, both obtained in 2023.
Behavioral Study: Characterizing Sensory Profiles in Parkinson’s Disease
This study aims to better understand how individuals with Parkinson’s disease (PD) perceive pain, especially those suffering from chronic low back pain. Researchers compare four groups: people with PD with or without pain, and people without PD with or without chronic pain. A battery of quantitative sensory tests (QST) is used to assess detection thresholds, pain thresholds (cold, heat, pressure), temporal summation, and pain inhibition via counter-irritation.
Participants also complete questionnaires assessing pain, cognition, mood, apathy, and pain-related expectations. A key component of the protocol is a pain anticipation paradigm, where visual cues (indicating low, moderate, or high pain) precede thermal stimulations, allowing researchers to assess how expectations influence pain perception.
Imaging Study: Brain Mechanisms of Pain Perception and Anticipation in Parkinson’s Disease
This neuroimaging study investigates how the brains of individuals with Parkinson’s disease—with or without chronic pain—process and anticipate pain, in comparison with healthy individuals and people with chronic pain unrelated to PD. Using fMRI, researchers measure brain activity in response to calibrated thermal stimulations and predictive visual cues.
The paradigm assesses both pain perception and the effect of anticipatory cues, with thermal stimulations rated on a visual analog scale. The study aims to uncover alterations in brain circuits involved in both perceptive and anticipatory pain processing in PD, and how these may relate to the development of chronic pain.
Connection with the behavioral study: The same pain anticipation paradigm is used in both studies
UK Biobank Study: Linking Pain and Parkinson’s in Population-Level Data
Using the UK Biobank cohort, this study investigates how pain reported by individuals with Parkinson’s relates to other clinical, cognitive, and genetic markers. The aim is to identify large-scale determinants of pain in PD and support the development of targeted treatments based on population data.