Objective: Different adipokines have been reported to play a role in the development, progression, and severity of knee osteoarthritis, but this association may be mediated by obesity. The aim of this study was to evaluate separately the associations of leptin and adiponectin with clinical severity and inflammatory markers in nonobese and obese women with knee osteoarthritis.
Design: Cross-sectional study with systematic inclusion of 115 women with symptomatic primary knee osteoarthritis. Age, physical exercise, symptoms duration, and body mass index were collected. Radiographic severity was evaluated according to Kellgren-Lawrence scale. Pain and disability were assessed by WOMAC-total, -pain, -function subscales. Two adipokines (leptin and adiponectin) and 3 inflammatory markers (TNF-α, hsCRP, and IL-6) were measured by ELISA in synovial fluid and serum.
Results: Synovial fluid adiponectin was associated with WOMAC pain, function, and total and with synovial fluid IL-6 in nonobese female knee osteoarthritis after controlling by confounders (partial correlation coefficient [PCC] = 0.395, 0.387, 0.427, and 0.649, respectively). Synovial fluid and serum leptin were significantly associated with IL-6 (PCC = 0.354) after controlling by confounders but associations with clinical severity and the rest of inflammatory markers were mitigated after control.
Conclusions: Adiponectin in synovial fluid was associated with clinical severity and local inflammatory markers in knee osteoarthritis women, while leptin relation was attenuated when controlled by confounders.
Keywords: adiponectin; clinical severity; inflammation; knee osteoarthritis; leptin.