Effects of yoga on stress and inflammatory factors in patients with chronic low back pain: A non-randomized controlled study

IntroductionYoga is known to reduce stress and inflammation which are related to chronic low back pain (CLBP). However, very few studies investigated the effect of yoga on stress and inflammation in patients with CLBP. We aimed to evaluate effects of the 12-week yoga program on back-related function, stress, and inflammatory factors in patients with CLBP.MethodsWe conducted a non-randomized controlled study. Premenopausal women with CLBP were recruited with a local flyer and allocated to Hatha yoga and untreated control groups. Before and after 12 weeks, CLBP by Roland–Morris Disability Questionnaire (RMDQ), back flexibility, stress by Symptoms of Stress Inventory (SOSI), and serum cortisol, tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) were evaluated. Effects of yoga were assessed with per-protocol and intention-to-treat analyses.ResultsBy the per-protocol analysis, RMDQ (p < 0.05) and back flexibility (p < 0.001) significantly improved in the yoga group (n = 14), whereas there were no significant differences in the control group (n = 11). Serum cortisol level and total SOSI score significantly decreased in the yoga group (both p < 0.05). TNF-α maintained in the yoga group whereas TNF-α significantly increased in the control group (p < 0.01). CRP did not changed significantly in both groups. The findings from the intention-to-treat analysis were consistent with those of the per-protocol analysis.ConclusionsThe present results suggest that yoga may be an effective treatment for CLBP and stress although the results should be confirmed with a large-scale randomized controlled trial.