Furthermore, a study that examined 34 patients with psoriatic arthritis, 17 patients with rheumatoid arthritis, and 36 healthy volunteers found that enthesitis-related sonographic changes were associated with increased total Hb, oxygen saturation, and collagen, whereas arthritis-related clinical and ultrasonography findings were related to increased THbV, reduced oxygenation and reduced water (and collagen) signals85. Here, GSTM1 is linked to rheumatoid arthritis.