A Mixed Methods Approach to Explore the Experience of Pain and Its Management in People with Parkinson's Disease.

Introduction: Pain in Parkinson's disease (PD) is common but poorly understood, with most research to date taking a mechanistic approach. This mixed methods study takes a broader biopsychosocial approach to assess and describe contributors of pain and explore pain management and the relationship between pain and physical activity in people with PD (PwPD) and chronic pain. Methods: A structured survey evaluated respondents' contributors of pain using standardized, self-report assessments of the following: pain, peripheral neuropathy, central nociplastic change, emotional dysregulation or pathology, and maladaptive cognitions. Semistructured individual interviews were conducted with purposively sampled survey participants and analyzed using inductive thematic analysis. Results: Eighty-nine PwPD (mean age 67 years, 55% female) completed the survey. The most common pain contributors were maladaptive cognitions (62%), central nociplastic change (49%), and emotional dysregulation (44%). Approaches to pain management and the response to physical activity were variable within and across individuals with different pain contributors. Four themes emerged from interviews with 24 participants: (1) causative perceptions of pain are diverse; (2) sense of control influences disease acceptance and exercise self-efficacy; (3) belief in the value of therapy; and (4) pain as the unspoken PD symptom. Physical activity was used by PwPD for pain management; however, the relationship between pain and physical activity varied based on sense of control. Conclusions: Clinicians should screen for pain and assess its contributors to provide individualized, multidimensional pain management that considers the biological, psychological, and social factors of pain in PwPD. It is plausible that such an approach would promote a better sense of control for PwPD.

The Associations Between Physical Activity, Sleep, and Mood with Pain in People with Parkinson's Disease: An Observational Cross-Sectional Study.

BACKGROUND: Pain is common in Parkinson's disease (PD). In general and chronic pain populations, physical inactivity, poor sleep, and anxiety are associated with worse pain. However, little is known about these potential predictors of pain in PD. OBJECTIVE: This cross-sectional observational study investigated associations between measures of physical activity, sleep, and mood with pain in people with PD. METHODS: Pain was measured using the King's PD Pain Scale and the Brief Pain Inventory (pain severity and interference) in 52 participants with PD. Independent variables were categorised by demographics (age, gender), disease severity (MDS-UPDRS) and duration, central sensitization (Central Sensitization Inventory), physical activity (Incidental and Planned Exercise Questionnaire), sleep (Pittsburgh Sleep Quality Index), and mood (Hospital Anxiety and Depression Scale). RESULTS: Univariate regression analyses showed that increased disease severity, longer disease duration, greater central sensitization, increased physical activity, poor sleep, anxiety, and depression were associated with worse pain in one or more pain measures (p < 0.05). Multivariate regression models accounted for 56% of the variance in the King's Pain Scale, 25% pain severity and 36% in pain interference. Poor sleep independently contributed to worse pain scores in all models (ß 0.3-0.4, p < 0.05). CONCLUSION: Increased physical activity, poor sleep, anxiety, and depression are associated with worse pain scores in people with PD. For optimal management of pain in people with PD, sleep and mood may need to be addressed. Further, the nature of the relationship between physical activity and pain in PD requires further investigation.

A Comparison of Activity Monitor Data from Devices Worn on the Wrist and the Waist in People with Parkinson's Disease.

BACKGROUND: It is unclear if it is appropriate for people with Parkinson's disease (PD) to wear activity monitors on the wrist because of the potential influence of impairments on the data. OBJECTIVE: The objective of this study was to determine (1) whether activity monitor data collected from devices worn at the wrist and waist are comparable and (2) the contribution of PD impairments to any differences in step and activity counts at the wrist and waist. METHODS: A total of 46 community-dwelling people with PD wore an accelerometer at the wrist and waist simultaneously for 1 week. Motor impairments (rigidity, bradykinesia, tremor, dyskinesia) were assessed using the Movement Disorders Society Unified Parkinson's Disease Rating Scale part III (motor examination) and part IV (motor complications). RESULTS: Higher values were recorded by the wrist monitor for steps/day (wrist, 9236 [standard deviation (SD) 3812]; waist, 5324 [SD 2800]; difference 3912; P < 0.001) and activity counts/day (wrist, 872,590 [SD 349,148]; waist, 186,491 [SD 101,989]; difference 686,099; P < 0.001). However, the wrist and waist values were strongly correlated (steps, r = 0.89; counts, r = 0.74; P ≤ 0.001). Increased tremor and dyskinesia explained 19% of the variation in the difference in average steps/day, and these variables plus reduced bradykinesia explained 24% of the variation in the difference in average activity counts/day. CONCLUSION: Wrist monitors are likely to overestimate activity, particularly in people with tremor and dyskinesia. Nonetheless, activity monitors can be worn on the wrist if the aim is to monitor change rather than accurately record activity.

Exercise-induced hypoalgesia is present in people with Parkinson's disease: Two observational cross-sectional studies.

BACKGROUND: Exercise is prescribed for people with Parkinson's disease to address motor and non-motor impairments, including pain. Exercise-induced hypoalgesia (i.e., an immediate reduction in pain sensitivity following exercise) is reported in the general population; however, the immediate response of pain sensitivity to exercise in people with Parkinson's disease is unknown. The purpose of this study was to investigate if exercise-induced hypoalgesia is present following isometric and aerobic exercise in people with Parkinson's disease, and if so, if it varies with the dose of aerobic exercise. METHODS: Thirty people with idiopathic Parkinson's disease and pain-free age-matched controls completed two observational studies evaluating the response to: (a) right arm isometric exercise; and (b) treadmill walking at low and moderate intensities. Pressure pain thresholds were measured over biceps brachii and quadriceps muscles immediately before and after exercise, with increased thresholds after exercise indicating exercise-induced hypoalgesia. RESULTS: Pressure pain thresholds increased in the Parkinson's disease group at all tested sites following all exercise bouts (e.g., isometric exercise, right bicep 29%; aerobic exercise, quadriceps, moderate intensity 8.9%, low intensity 7.1% (p ≤ 0.008)), with no effect of aerobic exercise dose (p = 0.159). Similar results were found in the control group. CONCLUSIONS: Overall, people with Parkinson's disease experienced an exercise-induced hypoalgesia response similar to that of the control group, the extent of which did not vary between mild and moderate doses of aerobic exercise. Further research is warranted to investigate potential longer term benefits from exercise in the management of pain in this population. SIGNIFICANCE: Isometric and aerobic exercise reduces pain sensitivity in people with Parkinson's disease. As exercise is important for people with Parkinson's disease, these results provide assurance that people with Parkinson's disease and pain can exercise without an immediate increase in pain sensitivity. The reduction in pain sensitivity with both modes and with low and moderate intensities of aerobic exercise suggests that people with Parkinson's disease can safely choose the mode and intensity of exercise that best suits their needs.