Chronic Pain Common in Parkinson’s Patients and Weighs Heavily on Quality of Life, Study Reports

Chronic pain is prevalent in Parkinson’s disease patients and its severity considerably impacts their daily life, work, and social relationships, a  study aiming to guide physicians in better managing this symptom reports. It also links chronic pain to such psychological ills as depression, low self-esteem, frustration and sleep deprivation.

The study, “Negative impact of severity of pain on mood, social life and general activity in Parkinson’s disease,” was published in the journal Neurological Research.

Parkinson’s non-motor symptoms are often reported prior to a definitive diagnosis, and become more frequent and severe with disease progression.

Several studies have shown that many Parkinson’s patients have abnormal pain processing that could be affected by levodopa treatment. Pain is also believed to be associated with the reappearance of motor symptoms when the effects of levodopa wear off. However, the characteristics of pain associated with Parkinson’s disease, its causes and underlying mechanisms, and its psychological impact have not been thoroughly analyzed.

Previous research revealed that neurons involved in pain processing, mood, and motor functions may be connected, suggesting a higher prevalence of fibromyalgia — a chronic rheumatic condition that causes widespread pain — and chronic pain in Parkinson’s patients.

Researchers in Canada and Pakistan conducted a case control study to assess patients’ perception of pain, as well as its impact on their quality of life, measures in terms that included daily activities, mood, and social relationships.

The study included 100 Parkinson’s patients (mean age, 70.4) and 100 healthy age- and gender-matched controls (mean age, 69.4) visiting a community-based movement disorders clinic between June 2011 to June 2012. Patients with dementia and/or atypical Parkinson’s were excluded.

Join the Parkinson’s forums: an online community for people with Parkinson’s Disease and their caregivers.

Chronic pain between the two groups was assessed using the Brief Pain Inventory (BPI), which measures pain severity (pain right now, pain at its worst and least since the last week), pain interference (disrupting  general activities, mood, walking ability, normal work environment, relationships with others, sleep and enjoyment of life) and pain frequency. A qualitative description of pain was also conducted.

Patients described pain as “exhausting,” “tiring,” “penetrating,” “miserable” and “unbearable” significantly more often than controls.

Among patients, those with depressive symptoms — as evidenced by a score of eight or higher in the Hospital Anxiety and Depression Scale (HADS) — reported pain as tender more frequently than those without depression. Controls with depressive symptoms were more likely to report pain as stabbing, tender and tiring compared to those without evidence of depression.

“These descriptions indicate a significant impact of pain on the psychological well-being of the patient,” the researchers wrote.

Subsequent analysis showed that patients overall scored higher than controls in “worst pain felt since last week” and in global pain severity. Among all participants with depressive symptoms, those with Parkinson’s had higher scores of worst pain felt and average pain felt since last week, as well as higher reported pain levels at the time of assessment and global pain severity than those in the control group.

Pain among Parkinson’s patients also interfered most with life quality, showing a greater impact that among controls on general activity, mood, walking ability, work, sleep, social relationships, and enjoyment. In agreement, these people also had more poorer global BPI pain interference scores.

Symptoms of depression led to similar differences – plus an additional higher impact on social relations – between patients and controls. Of note, depression was associated with greater difficulties in walking in the group without Parkinson’s.

Overall, these findings indicate the disruptive nature of pain in patients’ life, the importance of physical therapy and analgesics, and the relevance of mental health monitoring in people with Parkinson’s, the authors observed.

“Thus, pain associated with [Parkinson] can lead to psychological symptoms such as depression, low self-esteem, frustration and sleep deprivation,” they wrote.

The team suggests that the impact of pain in Parkinson’s needs to be further explored in larger studies.