Soluble lectin-like oxidized low-density lipoprotein receptor-1 levels in synovial fluid are correlated with disease severity of knee osteoarthritis

Objectives: This study was aimed to measure soluble lectin-like oxidized low-density lipoprotein receptor-1 (sLOX-1) levels in serum and synovial fluid (SF) of knee osteoarthritis (OA) patients and to investigate the correlation between sLOX-1 levels and the disease severity.

Design and methods: Two hundred and sixteen OA patients and 83 healthy controls were enrolled in this study. All OA patients were scored for Kellgren-Lawrence (KL) grade (0-4). The sLOX-1 levels were measured by enzyme-linked immunosorbent assay (ELISA).

Results: In OA patients, the mean sLOX-1 levels in SF were markedly lower than those in paired serum samples (P<0.01). The SF sLOX-1 levels increased with higher KL grade (P<0.01) and were significantly correlated with disease severity (r = 0.324, P<0.01). SF sLOX-1 level was the independent factor for predicting the disease severity of OA (β: 0.281, 95%CI: 0.145-0.396).

Conclusions: SF sLOX-1 levels were independently and positively associated with disease severity in knee OA.