Pain in Parkinson’s disease: Fluctuation and impact on quality of life

Background: Parkinson's disease (PD) is a chronic, progressive neurodegenerative disorder known for its motor and non-motor symptoms. Among the non-motor symptoms, pain is highly prevalent, significantly affecting patients' quality of life. Pain in PD can manifest in various forms, including musculoskeletal, dystonic, and neuropathic pain. Despite its high prevalence, pain in PD is often under-recognized and undertreated, necessitating further exploration of its characteristics and impact on quality of life. This study aims to assess the prevalence, types, and fluctuation of pain in PD patients and their relationship with motor and non-motor symptoms. Methods: This cross sectional study was conducted on 40 PD patients at Movement Disorders clinic in Ain Shams University . Data collection included demographic characteristics, medical history, and evaluation using standardized scales such as the King’s Parkinson’s Disease Pain Scale (KPPS), Movement Disorder Society–Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Non-Motor Symptoms Scale (NMSS), and the Parkinson’s Disease Questionnaire (PDQ-39). The correlation between these scales and the severity of pain was analyzed. Results: The study revealed a statistically significant correlation between KPPS and the wearing-off phenomenon (R=0.349, p=0.027), highlighting the association between motor fluctuations and pain severity. However, no significant correlations were found between KPPS and other scales like NMSS, PSQI, MDS-UPDRS, or PDQ summary index. Pain was highly prevalent among PD patients, with musculoskeletal and fluctuation-related pain being the most common types. Conclusion: Pain is a frequent and impactful non-motor symptom in Parkinson's disease that substantially affects patients' quality of life. The correlation between pain and motor fluctuations such as wearing off suggests that optimizing dopaminergic therapy could help manage pain in PD. Further studies are recommended to explore the management strategies for pain in PD and its complex interaction with other non-motor symptoms.