As shown in Table 3, statistical analysis revealed a correlation between GAGs and MMP-1 levels in the blood of patients with JIA before ETA therapy (r = 0.768, p = 0.000), at the 3rd (r = 0.678, p = 0.000), 6th (r = 0.738, p = 0.000), 12th (r = 0.779, p = 0.000), 18th (r = 0.692, p = 0.000), and 24th (r = 0.693, p = 0.000) months of therapy. This evidence concerns the gene MMP1 and juvenile idiopathic arthritis.