To study occurrence of and factors associated with self-limiting arthritis among patients fulfilling the 2010 ACR/EULAR classification criteria for rheumatoid arthritis (RA) (2010 RA criteria) in patients with ≤16 weeks׳ duration of joint swelling.
We applied the 2010 RA criteria in 1118 patients included in a 2-year longitudinal cohort. In all, 256 patients fulfilled the 2010 RA criteria at baseline; outcome was defined as either "self-limiting arthritis" (no DMARD use during follow-up, no swollen joints at last assessment, and no final clinical diagnosis of RA) or "persistent disease." The associations between baseline characteristics, including the components of the 2010 RA criteria score, and outcomes were studied.
In total, 36 of 256 patients (14.1%) classified as having RA had self-limiting arthritis. These patients differed from patients with persistent disease according to ACPA positivity (11.1% vs. 65.0%, p < 0.001), duration of joint swelling (median = 47.5 vs. 66.0 days, p = 0.002), 2010 RA criteria points (median = 6.0 vs. 7.0, p < 0.001), and ever smoking (52.8% vs. 74.5%, p = 0.01). Having no serology points and no duration points were independent predictors of self-limiting arthritis. The rate of self-limiting arthritis was 2.7% vs. 29.4% among ACPA positive vs. ACPA negative patients (p < 0.001), and 32.5% when duration of joint swelling was <4 weeks vs. 10.6% with longer duration (p < 0.001).
Negative ACPA status, short duration of joint swelling and being a never smoker were factors associated with self-limiting arthritis in early arthritis patients classified as having RA at presentation. Our findings contribute to identify patients who potentially do not need DMARDs and who should not be included in early RA clinical drug trials.