Abstract
To investigate the relationship of serum and urine levels of hyaluronic acid (HA) in rheumatoid arthritis (RA) patients to aging, joint destruction and clinical parameters, we measured HA levels by HA binding protein assay in 92 patients and 128 healthy controls.
Serum and urine levels of HA in healthy controls were elevated with aging over 70 years old. Serum and urine levels of HA in RA patients were elevated compared with those in 30 to 83 years old healthy controls (P<0.001) . There was no significant correlation between serum and urine HA in RA patients (r=0.018) . Serum levels of HA in stage III and IV in Steinbrocker's classification were significantly elevated compared with those in stage I (P<0.001) . Serum levels of HA did not show a significant correlation with inflammatory markers, including ESR (r=0.194, P=0.064), CRP level (r =0.202, P=0.053), WBC count (r=0.042, P=0.688) and IgG level (r=-0.081, P=0.445) .
These results suggest that the elevation of serum HA levels might be one of the evidences for premature senescence in RA patients.