Ultrasound versus clinical remission in patients with early rheumatoid arthritis: concordance and relationship with therapy discontinuation.

Objectives: To evaluate prevalence of ultrasonographic remission (USR) and concordance with clinical remission in "drug-free" or "on-treatment" patients with early rheumatoid arthritis (RA).

Methods: We carried out a cross-sectional study including consecutive early RA patients in SDAI remission ≥6 months in the period 06/2022 to 02/2023. CDAI, DAS28, DAS44 and Boolean remission were also evaluated. Patients underwent B-mode and Power Doppler (PD) assessments of 42 joints and 20 tendons. Synovitis, tenosynovitis and PD were graded semi-quantitatively (0-3) using standardised scores. Four definitions of USR were examined: USR1: absence of synovial hypertrophy (SH) and PD; USR2: SH≤1 and PD=0; USR3: SH≤1 and PD≤1; USR4: PD negative.

Results: Eighty patients were enrolled, of whom 12 drug-free. Overall remission rates were 100.0%, 83.7%, 91.2%, 96.2% and 80.0% for SDAI, CDIA, DAS28, DAS44 and ACR/EULAR Boolean criteria, respectively. 100% of drug-free patients were in remission according to all indices. The rate of USR in drug-free versus on-treatment remission was 58.3%, 66.7%, 66.7%, 83.3% versus 70.6%, 85.3%, 88.2%, 91.2% for USR1, USR2, USR3 and USR4, respectively.

Conclusions: While clinical remission seems more frequent in drug-free patients, USR is more often observed on-treatment.