RESUMEN
BACKGROUND AND OBJECTIVES: Low back pain (LBP) is a complaint of great importance among the elderly due to its significant impact on function. LBP could contribute to changes in the regulatory process of inflammatory mediators observed in elders. The aim of this study was to compare plasma levels of interleukin(IL)-6, soluble tumor necrosis factor receptor 1(sTNF-R1), and functionality among 3 groups of elderly women: GI, with LBP; GII, without LBP but reports of other pain; and GIII, without any reported pain. MATERIAL AND METHOD: This was an observational study of a subsample of the international Back Complaints in the Elders cohort study. IL-6 and sTNF-R1 were measured using the enzyme-linked immunosorbent assay. Functionality was assessed using the Timed Up and Go, gait speed and Roland Morris Disability Questionnaire; and pain, using the numerical pain scale. RESULTS: Two hundred and thirteen women aged 71.35 ± 4.76 years were included. GI presented the highest sTNF-R1 levels (p=0.016), worst TUG performance (p< 0.001) and slowest gait speed (p< 0.01) compared to GII and GIII, which were similar (p > 0.05). No difference was found between the IL-6 plasma levels in any of the groups. CONCLUSION: Elderly women with LBP had the highest sTNF-R1 plasma levels and the worst functional performance compared to elderly women with reports of other pain (not LBP) or no pain.