Evidence of musculoskeletal pain sensitization in patients with multiple sclerosis: Case-control study

Chronic musculoskeletal pain is a common symptom in individuals with multiple sclerosis (MS), however the underlying pain mechanisms remain complex and not fully understood. Therefore, this study aims to investigate the underlying pain mechanisms using different quantitative sensory testing (QST) and other self-reported measures compared to healthy controls.

A total of 133 participants (93 MS patients and 40 healthy controls) were included. Participants completed self-reported measures including brief pain inventory (BPI), pain sensitivity questionnaire (PSQ), painDETECT questionnaire (PDQ). Then, participants underwent QST testing including dynamic mechanical allodynia (DMA), pressure pain threshold (PPT), mechanical temporal summation (TS), cold hyperalgesia, and conditioned pain modulation (CPM). An independent two sample t-test was used to compare mean outcomes between two groups. A two-sided p-value ≤ 0.05 was considered statistically significant.

Individuals with MS reported significantly higher scores on the PSQ-Moderate subscale (p = 0.001), whereas differences in PSQ-Total and PSQ-Minor scores were not statistically significant. Compared to healthy controls, individuals with MS demonstrated higher DMA scores (p ≤ 0.003), Lower PPT at painful site (p ≤ 0.007), increased cold hyperalgesia for both painful (p ≤ 0.001) and contralateral sites (p ≤ 0.000), and significant differences in TS at painful (p ≤ 0.007) and contralateral sides (p ≤ 0.000). the CPM did not differ significantly between groups.

MS patients have hypersensitivity to moderate pain and robust differences in QST measures compared to healthy controls. This reflects the need for better mechanism-based assessment and treatment of musculoskeletal pain in patients with MS.