Objective The role of inflammation in osteoarthritis (OA) pathogenesis is unclear, and the associations between inflammatory cytokines and cartilage loss have not been reported. We determined the associations between serum levels of interleukin (IL)-6 and tumor necrosis factor-¦Á (TNF-¦Á), knee radiographic OA (ROA) and cartilage loss over 2.9 years in older adults. Methods A total of 172 randomly selected subjects (mean 63 years, range 52¨C78, 47% female) were studied at baseline and approximately 3 (range 2.6¨C3.3) years later. IL-6 and TNF-¦Á were assessed by radioimmunoassay. T1-weighted fat-suppressed magnetic resonance imaging of the right knee was performed at baseline and follow-up to determine knee cartilage volume. Knee ROA of both knees was assessed at baseline. Results At baseline, quartiles of IL-6 and TNF-¦Á were associated with increased prevalence of medial tibiofemoral joint space narrowing (OARSI grade ¡Ý1) in multivariate analyses [odds ratio (OR): 1.42 and 1.47 per quartile, respectively, both P < 0.05]. Longitudinally, baseline IL-6 predicted loss of both medial and lateral tibial cartilage volume (¦Â: −1.19% and −1.35% per annum per quartile, P < 0.05 and P < 0.01, respectively), independently of TNF-¦Á. Change in IL-6 was associated with increased loss of medial and lateral tibial cartilage volume (¦Â: −1.18% and −1.06% per annum per quartile, both P < 0.05) and change in TNF-¦Á was also negatively associated with change in medial cartilage volume (¦Â: −1.27% per annum per quartile, P < 0.05). Conclusions Serum levels of IL-6 and TNF-¦Á are associated with knee cartilage loss in older people suggesting low level inflammation plays a role in the pathogenesis of knee OA.
History
Publication title
Osteoarthritis and Cartilage
Volume
18
Issue
11
Pagination
1441-1447
ISSN
1063-4584
Department/School
Menzies Institute for Medical Research
Publisher
W B Saunders Co Ltd
Place of publication
32 Jamestown Rd, London, England, Nw1 7By
Rights statement
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