PRTN3 and rheumatoid arthritis: On assessment of the potential of IMM-AGE score to identify patients at risk of developing RA in the pre-arthritis phase, a significantly higher IMM-AGE score was observed in ACPA+ve patients with arthralgia (p = 0.032) who developed RA compared to ACPA−ve patients with arthralgia and those who do not develop RA at the baseline stage [Fig. 5a].