AMPD1 and rheumatoid arthritis: AMPD1 expression was observed to be differentially regulated in this way, being repressed among patients with RA who progressed to remission at the end of follow-up (0.1-fold expression at 1-month relative to baseline, figure 4B), but 3.3-fold induced among those who did not achieve remission (raw p=0.002 and 0.001, respectively; both p<0.05 after multiple test correction, figure 4C).