Ultrasound-defined remission for good functional status in rheumatoid arthritis

BACKGROUND & OBJECTIVES It has been shown that joint damage due to subclinical synovitis progresses despite apparent clinical remission in rheumatoid arthritis (RA). Hence, finding more objective methods to investigate subclinical synovitis has become a current issue. Ultrasonography (US) has been among the most investigated methods. This study was conducted to detect whether there was subclinical inflammation in RA patients in clinical remission by power Doppler ultrasonography (PDUS) and to evaluate the effects of this inflammation on upper extremity function. METHODS Forty five RA patients fulfilled the remission criteria of disease activity score 28 using erythrocyte sedimentation rate (DAS28-ESR), were enrolled in the study. Bilateral wrist, 2nd and 3th metacarpophalangeal and proximal interphalangeal joints and 2nd and 5th metatarsophalangeal joints were examined by PDUS. Upper extremity function was assessed with Michigan Hand Outcomes Questionnaire (MHQ) and handgrip strength. The pain was evaluated by visual analogue scale (VAS). RESULTS In 29 of 45 RA patients in clinical remission, synovitis was detected by PDUS at least in one joint. VAS and DAS28-ESR scores were significantly lower and total MHQ, some subgroup scores of MHQ (overall hand function, activity of daily living and work performance) and grip strength of the dominant hand were higher in patients with PD signal negativity. INTERPRETATION & CONCLUSIONS PDUS showed a crucial role in determining the subclinical synovitis. Subclinical synovitis negatively affects the upper extremity function. Ultrasound-defined remission may be considered for good functional status and real remission in patients with RA.