Associations Among Changes in Inflammatory Biomarkers, Pain Intensity, and Health-Related Quality of Life Following a 12-Week Aerobic Exercise Programme in Individuals with Non-Specific Chronic Low Back Pain

Background

Non-specific chronic low back pain (NSCLBP) is associated with persistent pain, reduced health-related quality of life (HRQoL), and low-grade systemic inflammation. This study examined associations among changes in inflammatory biomarkers, pain intensity, and HRQoL following a 12-week aerobic exercise programme.

Methods

This secondary analysis used data from a randomized controlled trial involving 41 participants with NSCLBP (intervention, n = 21; control, n = 20). Participants received either supervised aerobic exercise plus health education or health education alone for 12 weeks. Change scores for tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), pain intensity, and HRQoL domains were analysed using correlation and multiple regression analyses.

Results

Improvements in IL-6 (r = 0.434, p = 0.005) and hs-CRP (r = 0.444, p = 0.004) were significantly associated with improvements in pain intensity. No significant associations were observed between biomarker changes and HRQoL domains. Treatment allocation was the strongest independent predictor of improvement in physical HRQoL (β = 0.492, p = 0.017) and pain intensity (β = −0.512, p = 0.006).

Conclusions

Improvements in IL-6 and hs-CRP were associated with reductions in pain intensity but not with improvements in HRQoL. Treatment allocation was the strongest predictor of clinical improvement, suggesting that mechanisms beyond systemic inflammation may contribute to the benefits of aerobic exercise in NSCLBP.

Plain Language Summary

Non-specific chronic low back pain (NSCLBP) is a common condition that can cause persistent pain, reduce daily functioning, and negatively affect quality of life. Research suggests that low-grade inflammation may contribute to pain persistence, but it remains unclear how changes in inflammation relate to improvements in pain and health-related quality of life (HRQoL) following exercise-based rehabilitation.

This study examined the relationships among changes in inflammatory biomarkers, pain intensity, and HRQoL following a 12-week aerobic exercise programme in people with NSCLBP. Forty-one participants completed either a supervised aerobic exercise programme combined with health education or health education alone. Changes in inflammatory biomarkers (IL-6, hs-CRP, and TNF-α), pain intensity, and HRQoL were assessed over the intervention period.

The findings showed that improvements in IL-6 and hs-CRP were associated with reductions in pain intensity. However, changes in inflammatory biomarkers were not significantly associated with improvements in HRQoL. The strongest predictor of improvements in both pain and physical HRQoL was participation in the aerobic exercise programme.

These findings suggest that aerobic exercise can improve outcomes in people with NSCLBP, but the benefits may not be explained solely by reductions in inflammation. Other factors, including physical, psychological, and behavioural changes associated with exercise, may also contribute to recovery and improved well-being.