100 Section - Plasma Cytokines Associations with Clinical Outcomes in Chronic Low Back Pain Following Musculoskeletal Health Interventions

Objectives : Chronic low back pain (CLBP) has been linked to systemic inflammation, often assessed through the measurement of circulating cytokines. This study aimed to investigate whether levels of pro- and anti-inflammatory plasma cytokines are associated with changes in pain and disability among individuals with CLBP undergoing musculoskeletal health interventions (MHI), defined as participation in  Physical Therapy, Occupational Therapy, or Chiropractic care.

Design:  
Blood samples were collected from adults with CLBP (n=453) who rreceived MHI.  Plasma concentrations of interleukin-6, tumor necrosis factor-alpha, interferon-gamma, interleukin-10, interleukin-1 receptor antagonist, and the hormone leptin were measured using enzyme-linked immunosorbent assay. Pain intensity and disability were assessed with the Numeric Pain Rating Scale (NPRS) and the Oswestry Disability Index (ODI). Changes in outcomes were calculated as differences between baseline and six months after MHI. Associations between cytokine concentrations and changes in pain and disability were evaluated through linear regressions, both unadjusted and adjusted for age, sex, race, income, education, and relationship status.

Results: Participants had a mean age of 60 years and mean BMI of 31 kg/m². Baseline pain averaged 5.3 and ODI averaged 32.0, with modest changes over time (Δ pain = 0.8; Δ ODI = 0.7). No significant associations were found between baseline concentrations of pro-inflammatory cytokines, and changes in pain or disability. Similarly, anti-inflammatory cytokines showed no significant relationships with changes in pain or disability outcomes.

Conclusion: Baseline pro- and anti-inflammatory cytokine levels showed no association with changes in pain and disability among individuals with CLBP undergoing MHI, suggesting that single-point measurements of systemic inflammatory markers may not capture the complex biological processes influencing rehabilitation responses in CLBP.  Future research should incorporate longitudinal and broad cytokine profiling.