Pain and Fatigue in Parkinson's Disease: Exploring Their Interrelation and Mediating Variables

Area of Science:

• Neurology
• Psychiatry
• Pain Medicine

Background:

• Parkinson's disease (PD) frequently presents with non-motor symptoms (NMS), including pain (up to 85%) and fatigue.
• The co-occurrence of pain and fatigue in PD is common and impacts patient well-being.
• The specific relationship between pain and fatigue, and their mediating factors in PD, remains under-investigated.

Purpose of the Study:

• To investigate the association between pain and fatigue in Parkinson's disease patients.
• To explore the role of mediating variables, such as anxiety, depression, and motor symptoms, in the pain-fatigue relationship.

Main Methods:

• A cross-sectional study involving 53 Parkinson's disease patients with pain.
• Utilized validated scales: Spanish-King's-Parkinson-Pain-Scale (S-KPPS), Brief-Pain-Inventory (BPI), Fatigue-Severity-Scale (FSS), and Daily-Fatigue-Impact-Scale (DFIS).
• Performed correlation and partial correlation analyses, controlling for Levodopa-equivalent daily dose (LEDD), disease duration, UPDRS-III, anxiety, depression, and kinesiophobia.

Main Results:

• Fatigue severity (FSS) showed a moderate positive correlation with pain interference (BPI) and symptomatic burden (S-KPPS).
• No significant correlation was found between fatigue severity and pain intensity (BPI) or daily fatigue impact (DFIS) with any pain dimension.
• Anxiety, depression, and kinesiophobia influenced the significance of the pain-fatigue correlation, while LEDD and disease duration did not.

Conclusions:

• A moderate correlation exists between fatigue severity and pain interference/burden in PD patients.
• Non-motor symptoms like anxiety and depression are significant influencers in the relationship between pain and fatigue in PD.
• This study identifies pain as part of a tetrad of interrelated NMS in PD, alongside anxiety, depression, and fatigue.