Plasma and synovial fluid autotaxin correlate with severity in knee osteoarthritis.

Background This study aimed to investigate the relationships between plasma and synovial autotaxin and the severity in knee osteoarthritis (OA) patients. Methods A total of 90 participants (70 knee OA patients and 20 controls) were recruited. Autotaxin and high-sensitivity C-reactive protein (hs-CRP) levels were determined. The symptomatic and radiographic severity of OA was assessed using the Western Ontario McMaster University Osteoarthritis Index (WOMAC) scores and the Kellgren–Lawrence grades. Results OA patients had significantly higher circulating autotaxin and hs-CRP than controls. Plasma autotaxin was directly correlated with synovial fluid autotaxin (r = 0.639, P < 0.001). Additionally, plasma and synovial fluid autotaxin were associated with radiographic severity (P < 0.001). Furthermore, plasma and synovial fluid autotaxin levels were positively correlated with WOMAC scores (r = 0.558, P < 0.001 and r = 0.371, P = 0.002, respectively). Conclusion Plasma and synovial fluid autotaxin levels were positively correlated with the severity of OA. Thus, autotaxin has potential as a biomarker reflecting the severity of knee OA.