Subclinical synovitis measured by ultrasound in rheumatoid arthritis patients with clinical remission induced by synthetic and biological modifying disease drugs

Background: Rheumatoid arthritis (RA) patients with disease in clinical remission might show subclinical synovitis, which can be related to the progress of structural joint damage. Objective: To determine and compare the degree of synovial inflammation by ultrasound (US) in patients with RA in clinical remission, treated with DMARD or combination therapy with DMARD and anti-TNF. Methods: Hospital-based cross-sectional study of 58 patients with RA in sustained remission for at least 6 months by DAS28 <2.6, who attended the Rheumatology Service at the Hospital Universitario de Caracas. Patients underwent clinical, functional, and laboratory assessments. Ultrasound was performed in hands measuring synovial effusion, synovial hypertrophy and power Doppler signal; using a semiquantitative 4-point scale of 0 = none to 3 = severe. Chi-square and t-test were used to compare the clinical, functional, laboratory and US assessments between the DMARD (N = 37) and combination therapy with DMARD and anti-TNF (N = 21) groups. A p-value <0.05 was considered statistically significant. Results: Out of 58 patients, 25.9% had remission by US and 74.1% had synovial effusion or hypertrophy or positive power Doppler signal. Non-significant differences in US synovitis between the two groups were found. Conclusions: Persistent US activity was evident in a high percentage of rheumatoid arthritis patients in clinical remission by DAS28. No differences in subclinical synovitis measured by US were found between patients with DMARD and anti-TNF-induced clinical remission.