Background Several studies assessed disease activity with ultrasound in rheumatoid arthritis (RA) patients who were in clinical remission. These studies found subclinical synovitis in 48-73% of the patients. Subclinical synovitis is associated with radiographic progression and predicts short-term relapse in RA patients. So far, little is known about the association between subclinical synovitis and patient reported outcomes (PROs).
Objectives We evaluated the frequency of subclinical synovitis detected by ultrasound in RA patients in clinical remission while they are continuing synthetic and biological DMARDs. Our second objective was to compare PROs between patients with and without subclinical synovitis.
Methods Patients who are treated with the combination of a synthetic DMARD and biological DMARD (adalimumab or etanercept) and have low disease activity (DAS44<2.4 and SJC ≤1) were examined by ultrasound at baseline and after three months follow-up. Ultrasound examination included 26 joints (MCP2-5, PIP2-5, wrists, MTP2-5) graded on greyscale (GS; 0-3) and power Doppler (PD; 0-3). A joint with subclinical synovitis was defined as GS>1 and/or PD>0. Data on clinical and psychological characteristics, demographics, pain scores, functional ability (HAQ) and health-related quality of life (SF-36) were collected at baseline and at three months. Coping (Pain Coping and Cognition List [PCCL]), depression/anxiety symptoms (Hospital Anxiety and Depression Scale [HADS]) and fatigue (Bristol RA Fatigue Multi-Dimensional Questionnaire [BRAF-MDQ] and Fatigue Assessment Scale [FAS]) were collected at three months follow-up. Ultrasound subclinical synovitis positive and negative patients were compared on their PROs using the Wilcoxon-Mann-Whitney test and Chi-square test.
Results At baseline, 89 patients were included of which 71 patients had had their three months evaluation. Ultrasound revealed subclinical synovitis in 64% of the patients at baseline and in 68% at three months. In 44% of the patients subclinical synovitis was detected at both measurements. figure 1 shows baseline characteristics and patient reported outcomes at baseline and after three months. No clear pattern emerged on the PROs scores between subclinical synovitis positive and negative patients. At baseline functional ability differed between the two groups while health-related quality of life was similar. At three months similar levels were observed for functional ability, health-related quality of life, coping, depression symptoms and fatigue. HADS anxiety differed at 3 months.
Conclusions Subclinical synovitis is common in RA patients in clinical remission while they continue synthetic and biological DMARDs. In our study population we could not find a clear association between subclinical synovitis and PROs.
Disclosure of Interest None declared