Power Doppler ultrasound, but not low-field magnetic resonance imaging, predicts relapse and radiographic disease progression in rheumatoid arthritis patients with low levels of disease activity

Correlation of US-7 and US-9 Scores with Disease Activity Score using 28 Joint Counts (DAS28) in Patients with Rheumatoid Arthritis

Background

The attentive management of rheumatoid arthritis (RA) has attracted particular attention. The German 7-joint Ultrasound (US-7) is the first scoring system that combines bone erosions and soft tissue lesions in a single composite scoring system. This study aimed to assess the correlation between US-7 and Disease Activity Score Using 28 Joint Counts (DAS28) in clinically active RA patients. The efficacy of a novel ultrasound score-based system, the US-9 score (joints assessed with US-7 plus knees), was also compared with the standard US-7 score.

Methods

All the RA patients referred to the outpatient rheumatology clinic of Ghaem Hospital, Mashhad, Iran, during 2019-2020 were included. 28 joints were clinically examined to calculate DAS28. Nine joints were assessed comprising the German US-7 plus knees using grayscale ultrasonography (GSUS) and power Doppler ultrasonography (PDUS). Retrieved data were analyzed by SPSS software, version 22. The Spearman Correlation test was used to find the correlation between DAS28 and ultrasonographic findings. The statistical significance level was set at P<0.05.

Results

This study was composed of thirty-five RA patients with a mean age of 49.1±12.0 years. US-7 synovitis scores in GSUS and PDUS were significantly correlated with DAS28 (P=0.02, r=0.38 and P=0.003, r=0.48, respectively). US-9 synovitis scores in GSUS and PDUS were also significantly correlated with DAS28 (P=0.003, r=0.49 and P=0.006, r=0.45, respectively). The synovitis score measured by GSUS was significantly correlated with the GSUS knee synovial score (P=0.01, r=0.42).

Conclusion

Ultrasound assessment of large joints such as knees can be an effective approach to determining RA severity. However, it can be proposed that adding more involved joints into the sonographic assessment does not necessarily provide a better clinical correlation.

Real-World Clinical Equivalence of Generic and Branded Tofacitinib: A Prospective Longitudinal Cohort Study in Patients With Rheumatoid Arthritis

OBJECTIVES

To explore the clinical efficacy and safety of generic tofacitinib vs brand name tofacitinib in patients with rheumatoid arthritis (RA) in a single-center comparative study based on a prospective real-world cohort.

METHODS

Patients with RA receiving tofacitinib, either generic (Kelejia) or branded (Xeljanz), from March 2017, to December 31, 2022, were enrolled. The primary outcome was the simplified disease activity index (SDAI)-defined remission rate at month 6. Secondary outcomes included the rates of remission and low disease activity defined by other composite scores; European Alliance of Associations for Rheumatology response rate, and ultrasonic synovitis scores at months 1, 3, 6, and 12. Cost-effectiveness was investigated. Propensity score-based inverse probability of treatment weighting was adopted to reduce selection bias.

RESULTS

A total of 204 patients were enrolled: 59 in the generic group and 145 in the branded group. An SDAI-defined remission was achieved in 41.1% and 39.2% of patients in the generic and branded groups, respectively, at month 6 (P=.85). Rates of remission and low disease activity achievement, changes in clinical disease activity scores, and power Doppler and gray scale synovitis scores at months 1, 3, 6, and 12 were comparable between the 2 groups. Similar proportions of patients in the groups achieved moderate/good response at months 1, 3, 6, and 12. Rates of drug retention and adverse effects were also similar in the 2 groups. Both Kelejia and Xeljanz were cost-effective, but Kelejia had a lower average cost-effectiveness ratio.

CONCLUSION

Generic tofacitinib (Keljia) had equivalent clinical efficacy and safety and better cost-effectiveness compared with its originator (Xeljanz).

Comparison of Hand-Wrist Findings of Rheumatoid Arthritis Patients According to the Use of Synthetic and Biological Disease-Modifying Antirheumatic Drugs (DMARDs): A Clinical, Radiographic, and Ultrasonographic Study

OBJECTIVE

The aim of this study is to evaluate the hand-wrist findings in patients with rheumatoid arthritis (RA) using synthetic and a combination of synthetic and biological disease-modifying antirheumatic drugs (DMARDs) in terms of ultrasonographic, clinical, and radiographic data.

METHODS

The study is designed as a cross-sectional study, and 31 RA patients followed up in the rheumatology outpatient clinic were enrolled. Nineteen patients were using only synthetic DMARDs, and 12 patients were using a combination of synthetic and biological DMARDs. The clinical data of each patient were recorded simultaneously. Disease Activity Score-28 (DAS-28) was used for the assessment of disease activation, and the Health Assessment Questionnaire (HAQ) score was used for the evaluation of general health status. Bilateral proximal interphalangeal (PIP), metacarpophalangeal (MCP) joints, and the radiocarpal, ulnocarpal, and midcarpal joints of the patients were examined by ultrasonography (US). The Sharp-van der Heijde modified score was used to determine the radiographic damage.

RESULTS

There was no significant difference between the two groups in terms of demographic data, clinical findings, ESR, and CRP. When the groups were compared in terms of right and left PIP, MCP, and radiocarpal, ulnocarpal, and midcarpal synovitis grade total scores, no significant difference was found between the two groups. Radiographic total joint space scores were significantly lower in the group receiving only synthetic DMARD treatment (p=0.047) and 25-OH vitamin D levels were significantly higher (p=0.008).

CONCLUSION

This study revealed that there was no significant difference between groups except radiographic total joint space scores.

MMP-13, VEGF, and Disease Activity in a Cohort of Rheumatoid Arthritis Patients

Identifying certain serum biomarkers associated with the degree of rheumatoid arthritis (RA) activity can provide us with a more accurate view of the evolution, prognosis, and future quality of life for these patients. Our aim was to analyze the presence and clinical use of matrix metalloproteinase-13 (MMP-13), along with vascular endothelial growth factor (VEGF) and well-known cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) for patients with RA. We also wanted to identify the possible correlations between MMP-13 and these serological markers, as well as their relationship with disease activity indices, quality of life, and ultrasonographic evaluation. For this purpose, we analyzed serum samples of 34 RA patients and 12 controls. In order to assess serum concentrations for MMP-13, VEGF, TNF-α, and IL-6, we used the enzyme-linked immunosorbent assay (ELISA) technique. Our results concluded that higher levels of MMP-13, VEGF, TNF-α, and IL-6 were present in the serum of RA patients compared to controls, with statistical significance. We furthermore identified moderately positive correlations between VEGF, MMP-13, and disease activity indices, as well as with the ultrasound findings. We also observed that VEGF had the best accuracy (97.80%), for differentiating patients with moderate disease activity. According to the data obtained in our study, that although MMP-13, TNF-α and C-reactive protein (CRP) have the same sensitivity (55.56%), MMP-13 has a better specificity (86.67%) in the diagnosis of patients with DAS28_(4v) CRP values corresponding to moderate disease activity. Thus, MMP-13 can be used as a biomarker that can differentiate patients with moderate or low disease activity. VEGF and MMP-13 can be used as additional parameters, along with TNF-α and IL-6, that can provide the clinician a better picture of the inflammatory process, disease activity, and structural damage in patients with RA. Our data can certainly constitute a start point for future research and extended studies with multicenter involvement, to support the selection of individualized and accurate therapeutic management strategies for our patients.

Tenderness and radiographic progression in rheumatoid arthritis and psoriatic arthritis

OBJECTIVE

The aim of this study was to assess the predictive value of tenderness in the absence of swelling with consideration of other potential risk factors for subsequent radiographic progression in rheumatoid arthritis (RA) and psoriatic arthritis (PsA).

METHODS

Clinical and sonographic (grey scale and power Doppler (PD)) examination of 22 joints of the hand were performed in patients with RA and PsA. The impact of tenderness on progression after 2 years was analysed in non-swollen joints for RA and PsA separately with multilevel mixed logistic regression analysis.

RESULTS

We included 1207 joints in 55 patients with RA and 352 joints in 18 patients with PsA. In RA, tenderness was associated with radiographic progression after 2 years (model 2: OR 1.85 (95% CI 1.01 to 3.27), p=0.047), although the association of PD (OR 2.92 (95% CI 1.71 to 5.00), p<0.001) and erosions (OR 4.74 (95% CI 2.44 to 9.23), p<0.001) with subsequent structural damage was stronger. In PsA, we found a positive but not significant association between tenderness and radiographic progression (OR 1.72 (95% CI 0.71 to 4.17), p=0.23). In contrast, similarly to RA, erosions (OR 4.62 (95% CI 1.29 to 16.54), p=0.019) and PD (OR 3.30 (95% CI 1.13 to 9.53), p=0.029) had a marked effect on subsequent structural damage.

CONCLUSION

Our findings imply that tenderness in non-swollen joints in RA is associated with subsequent damage. In both diseases, additional risk factors, such as sonographic signs for synovitis and baseline radiographic damage are associated with radiographic progression.

Frequency of joint inflammation is associated with local joint damage progression in rheumatoid arthritis despite long-term targeted treatment

OBJECTIVES

To investigate whether in rheumatoid arthritis (RA) frequency of local joint inflammation is associated with radiographic joint damage progression in that joint.

METHODS

Data from 473 patients with RA and available radiographs from the BeSt study were used. Patients were treated to target (Disease Activity Score of ≤2.4) for a median of 10 years. At each study visit every 3 months, joints were assessed for swelling and tenderness. Radiographs of hands and feet were made yearly. A generalised linear mixed model was used to assess the association between the percentage of study visits at which clinical inflammation was observed in a joint (cumulative inflammation) and radiographic joint damage in that same joint. Clinical inflammation was primarily defined as joint swelling (with or without joint tenderness). For secondary analyses, we also investigated joint tenderness without joint swelling. Damage was measured as the percentage of the maximum possible Sharp-Van der Heijde score in a particular joint.

RESULTS

Cumulative local joint swelling was associated with local progression of radiographic damage in the same joint (β=0.14, 95% CI 0.13 to 0.15). This association was also found in a subset of joints that were swollen at least once. Cumulative local joint tenderness without concurrent local joint swelling was less strongly associated with local radiographic joint damage progression (β=0.04, 95% CI 0.03 to 0.05).

CONCLUSIONS

In RA, long-term cumulative local joint inflammation is associated with joint damage progression in the same joint.

Assessment of inflammation in patients with rheumatoid arthritis using thermography and machine learning: a fast and automated technique

Objectives

Sensitive detection of joint inflammation in rheumatoid arthritis (RA) is crucial to the success of the treat-to-target strategy. In this study, we characterise a novel machine learning-based computational method to automatically assess joint inflammation in RA using thermography of the hands, a fast and non-invasive imaging technique.

Methods

We recruited 595 patients with arthritis and osteoarthritis, as well as healthy subjects at two hospitals over 4 years. Machine learning was used to assess joint inflammation from the thermal images of the hands using ultrasound as the reference standard, obtaining a Thermographic Joint Inflammation Score (ThermoJIS). The machine learning model was trained and tuned using data from 449 participants with different types of arthritis, osteoarthritis or without rheumatic disease (development set). The performance of the method was evaluated based on 146 patients with RA (validation set) using Spearman’s rank correlation coefficient, area under the receiver-operating curve (AUROC), average precision, sensitivity, specificity, positive and negative predictive value and F1-score.

Results

ThermoJIS correlated moderately with ultrasound scores (grey-scale synovial hypertrophy=0.49, p<0.001; and power Doppler=0.51, p<0.001). The AUROC for ThermoJIS for detecting active synovitis was 0.78 (95% CI, 0.71 to 0.86; p<0.001). In patients with RA in clinical remission, ThermoJIS values were significantly higher when active synovitis was detected by ultrasound.

Conclusions

ThermoJIS was able to detect joint inflammation in patients with RA, even in those in clinical remission. These results open an opportunity to develop new tools for routine detection of joint inflammation.

Ultrasound-detected inflammation is more common in clinically manifest hand osteoarthritis than in painless bony enlarged finger joints: subanalysis of the population-based Bruneck study

Purpose:

The aim of this article is to examine the extent of structural and inflammatory lesions by ultrasound in elderly subjects with hand osteoarthritis (HOA) fulfilling the ACR classification criteria (Group A), in subjects with painless enlarged finger joints (Group B), and in individuals without clinical abnormalities at hands (Group C).

Methods:

This study was nested within the population-based, prospective Bruneck study; 293 subjects of ⩾65 years of age were assessed. Clinical and ultrasound assessment was conducted at wrists and finger joints. Gray scale synovitis (GSS), Power Doppler (PD), osteophytes, and erosions were scored semiquantitatively (0–3). The Short Form Score for the Assessment and Quantification of Chronic Rheumatic Affections of the Hands (SF-SACRAH), the Health Assessment Questionnaire (HAQ), and the Functional Index for Hand Osteoarthritis (FIHOA) were retrieved.

Results:

Most subjects had ⩾1 ultrasound abnormality, of which osteophytes were the most prevalent finding in all groups (Group A: 100%, Group B: 99.4%, and Group C: 93.9%). GSS and PD-signals were more common in Group A than in Group B (94% versus 67% and 33% versus 13%, respectively). In Group C, GSS was observed in 39.4% of subjects. In subjects with HOA, the SF-SACRAH correlated with osteophyte scores (corr_coeff = 0.48), and the FIHOA correlated with the osteophyte (corr_coeff = 0.42) and PD scores (corr_coeff = 0.33).

Conclusion:

GSS and PD were more frequent in patients with symptomatic HOA than in cases with painless bony enlargements and subjects without clinical joint abnormalities. Functional restriction in HOA is associated with structural and inflammatory ultrasound changes.

Machine learning-based prediction of relapse in rheumatoid arthritis patients using data on ultrasound examination and blood test

Recent effective therapies enable most rheumatoid arthritis (RA) patients to achieve remission; however, some patients experience relapse. We aimed to predict relapse in RA patients through machine learning (ML) using data on ultrasound (US) examination and blood test. Overall, 210 patients with RA in remission at baseline were dichotomized into remission (n = 150) and relapse (n = 60) based on the disease activity at 2-year follow-up. Three ML classifiers [Logistic Regression, Random Forest, and extreme gradient boosting (XGBoost)] and data on 73 features (14 US examination data, 54 blood test data, and five data on patient information) at baseline were used for predicting relapse. The best performance was obtained using the XGBoost classifier (area under the receiver operator characteristic curve (AUC) = 0.747), compared with Random Forest and Logistic Regression (AUC = 0.719 and 0.701, respectively). In the XGBoost classifier prediction, ten important features, including wrist/metatarsophalangeal superb microvascular imaging scores, were selected using the recursive feature elimination method. The performance was superior to that predicted by researcher-selected features, which are conventional prognostic markers. These results suggest that ML can provide an accurate prediction of relapse in RA patients, and the use of predictive algorithms may facilitate personalized treatment options.

Musculoskeletal ultrasound for treating rheumatoid arthritis to target-a systematic literature review

OBJECTIVE

We aimed to systematically review the literature to retrieve evidence on the diagnostic and prognostic value of musculoskeletal ultrasound for a treat to target (T2T) approach in RA.

METHODS

Eight research questions were developed addressing the role of ultrasound (including different ultrasound scores and elementary lesions) for diagnosis, monitoring and prognosis of RA. PubMed and EMBASE were searched (2005-2020). Articles on RA and reporting data on musculoskeletal ultrasound were included and extracted according to the underlying questions, and risk of bias assessed according to the study design.

RESULTS

Out of 4632 records, 60 articles were included. Due to clinical heterogeneity, meta-analysis was not possible. Ultrasound better predicted disease relapses with respect to clinical examination in patients in remission, while both methods performed similarly in predicting response to therapy, achievement of remission and radiographic progression. Ultrasound was superior to clinical examination in diagnosing joint involvement using another imaging modality, such as magnetic resonance imaging, as reference. Limited ultrasound scores performed like more extensive evaluations for the detection of joint inflammation and for outcome prediction. Higher ultrasound scores of synovitis were linked to poor outcomes at all disease stages, but a specific cut-off distinguishing between low- and high-risk groups did not emerge.

CONCLUSIONS

These data confirm the pivotal role of ultrasound when evaluating synovial inflammation and when identifying RA patients at higher risk of relapse. Further research is needed to better define the role of ultrasound in a T2T management strategy in moderately-to-highly active RA.

Superb microvascular imaging is as sensitive as contrast-enhanced ultrasound for detecting synovial vascularity in rheumatoid arthritis

BACKGROUND

Detection of synovitis is essential for assessing rheumatoid arthritis (RA) activity and predicting prognosis. This study aimed to compare the diagnostic performance of superb microvascular imaging (SMI) with that of contrast-enhanced ultrasound (CEUS) in patients with RA in clinical remission.

METHODS

SMI and CEUS were applied to 63 patients with active RA and 48 patients with RA in clinical remission. Differences in positive synovial vascularity (SV) and its semi-quantitative scale were observed, and the correlations of SMI and CEUS results with C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factor (RF) were analyzed.

RESULTS

For the 63 joints with active RA, the detection rates of SV as determined by SMI and CEUS were 90.5% (95% CI: 83.0-97.9%) and 93.7% (95% CI: 87.5-99.8%), respectively, with no significant difference observed between the two modalities (t=-1.137; P=0.260). There was good agreement between the two modalities in detecting positive blood flow (Kappa =0.784) and blood flow signal score (Kappa =0.792). For the 48 joints with clinical remission, the detection rates of SV determined by SMI and CEUS were 79.2% (95% CI: 67.2-91.1%) and 83.3% (95% CI: 72.4-94.3%), respectively, with no significant difference found between the two modalities (t=1.000; P=0.322). There was high consistency between the two modalities in detecting positive blood flow (Kappa =0.727) and blood flow signal score (Kappa =0.661). The vascularity scores of SMI and CEUS were positively correlated with CRP, ESR, and RF in the joints with active RA, but not in those with clinical remission.

CONCLUSIONS

SMI is as sensitive as CEUS for detecting vessels in the synovium and displaying local SV in patients with RA who achieve clinical remission.

Advances in Ultrasound Imaging in Rheumatology-What Do They Mean and What Challenges Do They Pose? The Example of Microvascular Imaging

Musculoskeletal ultrasound is an important tool for the monitorization of inflammatory rheumatic diseases, with subclinical synovitis being frequently detected in ultrasound scans of patients in clinical remission. It has been shown, for example, that the presence of Power Doppler signal synovial membrane has prognostic value for patients with rheumatoid arthritis. Microvascular imaging technologies significantly improve the sensitivity for slow-flow vessels and may potentially detect subclinical inflammation when Power Doppler fails to do so. The authors briefly discuss the implications of the use of such techniques in rheumatology setting and review available evidence.

Ultrasound-detected tenosynovitis as a risk factor for flares in rheumatoid arthritis patients in clinical remission

BACKGROUND

Our objective was to investigate the value of ultrasound (US) detected synovitis and tenosynovitis as risk factors for short term flare in rheumatoid arthritis (RA) patients in clinical remission.

METHODS

Consecutive RA patients in clinical remission (DAS28 ERS < 2.6) for at least 3 months underwent Power Doppler ultrasound (PDUS) examination of 1st to 6th extensor compartments at the wrist, 2nd to 5th finger flexor, posterior tibial tendon, and peroneal tendons. To assess synovitis, carpal joints, 1st to 5th metacarpophalangeal (MCP) joints, and 2nd to 5th interphalangeal proximal (IPP) joints were bilaterally examined. Synovitis and tenosynovitis were defined according to OMERACT. Patients were followed for 1 year. Disease flare was defined as an increase in disease activity generating the need for a change in therapy by the attending rheumatologist.

RESULTS

Ninety patients were included. After 1 year of follow-up, 26 patients (29%) experienced a flare. At baseline 39%, 23% and 8% had US-detected synovitis, tenosynovitis or both, respectively. In the 1-year period after the baseline US examination, US-detected tenosynovitis (RR: 4.9; 95% CI: 2.2-10.8) was associated with an increased risk of exacerbation. This association was not shown with US-detected synovitis (RR: 1.3; 95% CI: 0.76-2.2). In the multivariate analysis, only subclinical tenosynovitis (OR: 9.8; 95% CI: 2.5-39.1; p = 0.001) and baseline DAS28 (OR: 5.7; 95% CI: 1.1-31.6; p = 0.047) were significantly associated with an increased risk of having a flare.

CONCLUSION

In our study, subclinical tenosynovitis was associated with disease flare in patients with RA in clinical remission.

KEY POINTS

• Synovitis and tenosynovitis are risk factors for short term flare in RA patients in clinical remission. • Subclinical tenosynovitis, but not synovitis, was associated with disease flare in patients with unstable remission. • Ultrasound-detected tenosynovitis could be useful to predict relapses in RA patients in clinical remission.

Defining the Optimal Strategies for Achieving Drug-Free Remission in Rheumatoid Arthritis: A Narrative Review

Background: It is now accepted that the optimum treatment goal for rheumatoid arthritis (RA) is sustained remission, as this has been shown to be associated with the best patient outcomes. There is little guidance on how to manage patients once remission is achieved; however, it is recommended that patients can taper therapy, with a view to discontinuing and achieving drug-free remission if treatment goals are maintained. This narrative review aims to present the current literature on drug-free remission in rheumatoid arthritis, with a view to identifying which strategies are best for disease-modifying anti-rheumatic drug (DMARD) tapering and to highlight areas of unmet clinical need. Methods: We performed a narrative review of the literature, which included research articles, meta-analyses and review papers. The key search terms included were rheumatoid arthritis, remission, drug-free remission, b-DMARDS/biologics, cs-DMARDS and tapering. The databases that were searched included PubMed and Google Scholar. For each article, the reference section of the paper was reviewed to find additional relevant articles. Results: It has been demonstrated that DFR is possible in a proportion of RA patients achieving clinically defined remission (both on cs and b-DMARDS). Immunological, imaging and clinical associations with/predictors of DFR have all been identified, including the presence of autoantibodies, absence of Power Doppler (PD) signal on ultrasound (US), lower disease activity according to composite scores of disease activity and lower patient-reported outcome scores (PROs) at treatment cessation. Conclusions: DFR in RA may be an achievable goal in certain patients. This carries importance in reducing medication-induced side-effects and potential toxicity, the burden of taking treatment if not required and cost effectiveness, specifically for biologic therapy. Prospective studies of objective biomarkers will help facilitate the prediction of successful treatment discontinuation.

Ultrasonography of auricular cartilage is a potential tool for diagnosing relapsing polychondritis and monitoring disease activity

Aim

To assess the clinical utility of ultrasonography in the diagnosis and monitoring of disease activity in relapsing polychondritis (RP).

Methods

Auricular and nasal chondritis of 6 patients with RP were assessed by ultrasonography before treatment initiation. Changes in the ultrasonographic and clinical findings and serum inflammatory markers were longitudinally assessed. Ultrasonography was also performed in 6 patients with repeat ear trauma, 6 patients with auricular cellulitis and 6 healthy controls for comparison among groups.

Results

In all cases of RP, ultrasonographic findings before treatment revealed low‐echoic swollen auricular and nasal cartilage and perichondral soft‐tissue with increased power Doppler signals (PDS) corresponding to biopsy findings. After 2‐month treatment with prednisolone (PSL) combined with methotrexate, clinical and serum inflammatory markers were completely resolved. Although swollen perichondral soft‐tissue, cartilage and PDS on auricular ultrasonography were also significantly improved, PDS remained in 2 of 6 cases, which showed flare early after tapering PSL. Finally, ultrasonographic findings of RP were substantially differentiated between patients with repeat trauma and cellulitis and healthy controls based on the thickness of soft tissue around the cartilage, PDS and subperichondral serous effusion.

Conclusion

Assessment of RP lesions by ultrasonography is useful for the evaluation of cartilaginous lesions and monitoring of disease activity, especially when considering the treatment response and the timing of drug tapering.

Anti-Cyclic Citrullinated Peptide Antibodies Correlate to Ultrasound Synovitis in Rheumatoid Arthritis Better Than C-Reactive Protein

OBJECTIVES

The aim of this study was to compare ultrasound (US) grading and laboratory measures in patients with rheumatoid arthritis.

METHODS

Two-hundred four patients with rheumatoid arthritis who received US evaluation for synovitis were included after excluding those using tocilizumab. Ultrasound grading of synovial hypertrophy (SH) and power Doppler (PD) at the most severe site were recorded. An assessment of the correlation of laboratory measures and US grading was conducted by reviewing the electronic medical records.

RESULTS

High-titer anti-cyclic citrullinated peptide (anti-CCP) antibodies positivity was associated with SH grade ≥2 (odds ratio [OR], 6.00; 95% confidence interval [CI], 1.78-20.2) and PD grade ≥2 (OR, 5.56; 95% CI, 1.82-16.9). Recent C-reactive protein (CRP) levels ≥0.3 mg/dL were associated with SH grade ≥2 (OR, 3.13; 95% CI, 1.38-7.10) and PD grade ≥2 (OR, 2.38; 95% CI, 1.31-4.31). Anti-CCP antibody levels correlated with US scores better than the levels of CRP with higher Spearman ρ correlation coefficients. Most of the patients with recent CRP levels <0.3 mg/dL had US synovitis. In logistic regression, high levels of anti-CCP antibodies and CRP were both independently associated with SH grade ≥2 and PD grade ≥2.

CONCLUSIONS

Higher levels of anti-CCP antibodies and CRP may predict synovitis on US, whereas discrepancies existed between inflammatory markers and US grading. These findings suggest that US has a role in the comprehensive assessment of disease activity, especially for patients with high-titer positive anti-CCP antibodies.

Value of MRI and ultrasound for prediction of therapeutic response and erosive progression in patients with early rheumatoid arthritis managed by an aggressive treat-to-target strategy

OBJECTIVES

To investigate if inflammation detected by MRI or ultrasound at rheumatoid arthritis (RA) onset is predictive of erosive progression or poor response to methotrexate monotherapy, and to investigate if subclinical inflammation in remission is predictive of future treatment escalation or erosive progression.

METHODS

In a 2-year study, 218 patients with disease-modifying antirheumatic drug-naïve early RA were treated by a tight-control treat-to-target strategy corresponding to current recommendations. MRI and ultrasound were performed at regular intervals. Baseline imaging-based inflammation measures were analysed as predictors for early methotrexate failure and erosive progression using univariate and multivariate regression adjusted for clinical, laboratory and radiographic measures. In patients in remission after 1 year, imaging measures were analysed as predictors of treatment escalation and erosive progression during the second year. The added value of imaging in prediction models was assessed using receiver operating characteristic analyses.

RESULTS

Baseline MRI inflammation was associated with MRI erosive progression and ultrasound with radiographic erosive progression. No imaging inflammation measure was associated with early methotrexate failure. Imaging inflammation was present in a majority of patients in clinical remission. Tenosynovitis was associated with treatment escalation, and synovitis and tenosynovitis with MRI/radiographic erosive progression during the second year. Imaging information did not improve prediction models for any of the outcomes.

CONCLUSIONS

Imaging-detected inflammation, both at diagnosis and in remission, is associated with elements of future disease development. However, the lack of a significant effect on prediction models indicates limited value of systematic MRI and ultrasound in management of early RA.

Joint inflammation tends to recur in the same joints during the rheumatoid arthritis disease course

OBJECTIVES

We investigated whether local joint swelling recurs in the same joints over time in patients with rheumatoid arthritis (RA) who are treated to target.

METHODS

Patients with newly diagnosed RA participating in the Behandel-Strategieën, "treatment strategies" (BeSt) study (n=508) were followed for median 10 years while receiving Disease Activity Score (DAS) ≤2.4 steered treatment. Every 3 months 68 joints were assessed for the presence of swelling. We evaluated whether baseline local joint swelling was predictive for swelling in the same joint during follow-up using a multilevel mixed-effect logistic regression model. Different strategies were used to account for missing data. A permutation test was performed to assess if joint swelling was better predicted by baseline swelling of the joint itself than by baseline swelling of randomly selected other joints.

RESULTS

In 46% of the joints that were swollen at baseline, joint swelling later recurred at least once during follow-up. Joint swelling at baseline was statistically significantly associated with swelling in the same joint during follow-up (OR 2.37, 95% CI 2.30 to 2.43, p<0.001), and also specifically with recurrent swelling in the same joint (OR 1.73, 95% CI 1.37 to 1.59, p<0.001). Local joint swelling was better predicted by baseline swelling of that particular joint than by baseline swelling of other joints (p<0.001).

CONCLUSION

Joint swelling tends to recur locally in the joints swollen at RA onset. This suggests that local factors influence the manifestation of joint inflammation over time.

Dissociation between 2-[18F]fluoro-2-deoxy-D-glucose positron emission computed tomography, ultrasound and clinical assessments in patients with non-severe rheumatoid arthritis, including remission

Background

Inflammation of patients joints with severe disease activity of rheumatoid arthritis (RA) has already been visualized and quantified by 2-[¹⁸F]fluoro-2-deoxy-D-glucose positron emission computed tomography ([¹⁸F] FDG PET/CT), but little is known about the metabolic status and its relationship with clinical and ultrasonography (US) metrology in patients with low/moderate activity or in remission.

Methods

Clinical assessments [based on 28-joint disease activity score (DAS₂₈-CRP) and Clinical Disease Activity Index (CDAI)], [¹⁸F] FDG PET/CT, US and X-ray were performed on 63 RA patients classified into remission or low/moderate or severe disease activity groups. PET/CT was visually and then semi-quantitatively analysed by determining the standardized uptake value (SUV) of positive joints.

Results

Of the 1764 joints, 21.1% were tender only, 13.7% swollen only, 27.6% tender or swollen, 7.3% tender and swollen, 20.5% PET/CT-positive and 8.6% US-positive. PET and US measurements were correlated, albeit with poor concordance. The positive predictive value of PET/CT for clinical evaluation (tender and/or swollen) was low, whereas its negative predictive value was high. Highly significant differences were found with the number of PET/CT-positive joints and with cumulative SUV between “severe” and “non-severe” patients (including those in remission and those with low/moderate activity) and not between those classified as “remission” and “non-remission” or “remission” and “low/moderate activity”. Moreover, the correlation between PET/CT measurements and clinical activity was positive only in the CDAI severe disease group. In patients in remission or with low/moderate activity, only 20–30% of joints were PET/CT-negative. In remission, PET/CT and US were positive in different joints, and PET/CT-positive but US-negative joints mainly exhibited RA (38.1%) or normal (49.2%) and not osteoarthritic (12.7%) X-ray patterns.

Conclusions

[¹⁸F] FDG PET/CT was effective at distinguishing patients with severely active disease from other patients. In non-severe RA patients, including those in remission, PET/CT results are discordant from US and clinical observations. A longitudinal analysis is needed to explore the clinical relevance of such infra-clinical disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-021-00196-1.

Rheumatoid Arthritis Relapse and Remission - Advancing Our Predictive Capability Using Modern Imaging

Clinical remission has become an achievable target for the majority of patients with rheumatoid arthritis, but subclinical inflammation as assessed by ultrasound and magnetic resonance imaging (MRI) has been demonstrated to be frequent in patients in clinical remission. Subclinical synovitis has been shown to be linked to both subsequent structural damage progression and a risk of flare, demonstrating that subclinical synovitis represents incomplete suppression of inflammation and questions whether it is appropriate only to use clinical composite scores as treatment target in clinical practice. Maintaining a state of remission has proven important as sustained clinical remission impacts long-term outcome regarding joint damage progression, physical function and quality of life. Treating subclinical inflammation has been attempted and has led to more frequent strict clinical remission and better physical function, but also to more adverse events. Thus, an overall benefit of incorporating imaging goals in treat-to-target strategies has not been documented. However, in patients in clinical remission on biological disease-modifying anti-rheumatic drugs, both ultrasound and MRI may aid in the clinical decision regarding whether drug tapering or even discontinuation should be attempted.

Positive rate and prognostic significance of the superb microvascular imaging signal in joints of rheumatoid arthritis patients in remission with normal C-reactive protein levels and erythrocyte sedimentation rates

PURPOSE

This study aimed to evaluate the positive rate and prognostic significance of superb microvascular imaging (SMI) in rheumatoid arthritis (RA) patients in remission with normal C-reactive protein (CRP) levels and erythrocyte sedimentation rates (ESR).

METHODS

The study enrolled 112 RA patients, and ultrasound (US) assessment was performed on 28 joints of each patient.

RESULTS

The SMI signal-positive rates for each joint were: metacarpophalangeal (MCP) joints: 20.5%, wrist joints: 43.8%, metatarsophalangeal (MTP) joints: 17.0%, and other foot joints: 25.0%. Investigation of the prognostic significance of the SMI signal in each joint revealed that only in the MTP joints was the total score of the SMI signal in the patients with relapse significantly higher than that in the patients with remission (P = 0.01). Comparison of the receiver operating characteristics curves for predicting relapse showed that the area under the curve (AUC) of the MTP joints was the highest (AUC = 0.66) of the investigated joints. The optimal threshold for the total MTP SMI score was 1 (accuracy = 83.3%). Positive/negative data of the SMI signal in the MTP joints were not significantly associated with the values of conventional disease activity markers.

CONCLUSION

In RA patients in remission with normal CRP and ESR levels, the percentage of positive SMI signal was highest in the wrist joints. However, the accuracy of the SMI signal for predicting relapse was greatest for the MTP joints, suggesting that US assessment of the MTP joints by SMI is useful for predicting relapse in these patients.

The sonographic identification of cortical bone interruptions in rheumatoid arthritis: a morphological approach

Bone erosions are the hallmark of structural damage in rheumatoid arthritis (RA). Among imaging techniques, ultrasonography (US) has emerged as an accurate, reliable, repeatable, low-cost and non-invasive imaging modality to detect erosive changes in RA. However, small interruptions of the cortical bone detectable by last generation US equipment do not necessarily represent bone erosions. According to the available data, in addition to cortical bone interruption itself, only a few morphological US findings have been proposed to define RA bone erosions. However, other additional features may be considered to facilitate the interpretation of US cortical bone interruptions in RA. These could be summarised using the following four domains: size, site, shape and scenery. This hypothesis article provides a critical literature review of US features characteristic of RA bone erosions and pictorial evidence supporting the potential role of a morphological analysis in the US identification of bone erosions in RA patients.

Plain language summary

The ultrasonographic morphology of cortical interruptions is helpful for the identification of bone erosions in rheumatoid arthritis: the "four Ss" approach Bone erosions are characteristic features of rheumatoid arthritis. They are associated with a more aggressive disease and with irreversible physical disability. In recent years, ultrasonography has emerged as an accurate and reliable technique for the detection of bone erosions, that appear as interruptions of the cortical bone with variable size. However, cortical bone interruptions do not necessarily represent bone erosions. Since bone erosions represent the earliest evidence of the destructive behaviour of RA, their identification is crucial.Besides the cortical interruption itself, only a few morphological ultrasonographic features were proposed to characterise bone erosions in rheumatoid arthritis.We believe that a morphological approach, including size, site, shape and scenery, may be considered to facilitate the interpretation of ultrasonographic cortical bone interruptions in rheumatoid arthritis.In this hypothesis article we carried out a critical review of the scientific literature and provided extensive pictorial evidence of the ultrasonographic spectrum of cortical interruptions supporting the potential role of considering the "four Ss" for the ultrasonographic identification of bone erosions in rheumatoid arthritis.

Clinical utility of F-18 sodium fluoride PET/CT for estimating disease activity in patients with rheumatoid arthritis

Background

The present study aimed to investigate the clinical implication of F-18 sodium fluoride (NaF) positron emission tomography/computed tomography (PET/CT) for assessing the disease activity of rheumatoid arthritis.

Methods

Seventeen patients with rheumatoid arthritis according to the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria were prospectively enrolled. All enrolled patients underwent F-18 NaF PET/CT along with physical examination, blood test, and ultrasonography. On PET/CT images, two quantitative parameters, F-18 NaF uptake of the joint (joint SUV) and joint-to-bone uptake ratio, were measured for each of the 28 joints included in calculating the disease activity score in 28 joints using erythrocyte sedimentation rate (DAS28-ESR). The relationship between PET/CT parameters and clinical factors and the predictive values of PET/CT parameters for joints with synovitis and high disease activity were evaluated.

Results

Tender joints (joint SUV, 13.6±8.4; joint-to-bone uptake ratio, 1.70±1.02) and both tender and swollen joints (joint SUV, 13.9±5.4; joint-to-normal bone uptake ratio, 1.81±0.76) had significantly higher joint SUV and joint-to-bone uptake ratio than joints without synovitis (joint SUV, 6.0±2.4; joint-to-bone uptake ratio, 0.74±0.31; P<0.001). On correlation analysis, summed joint SUV (P=0.002, correlation coefficient=0.705) and summed joint-to-bone uptake ratio (P<0.001, correlation coefficient=0.861) of 28 joints showed strong positive correlation with DAS28-ESR after adjustment for age and body mass index. Summed joint SUV showed significant positive correlations with ultrasonography findings (grey scale ultrasonography: P=0.047, correlation coefficient =0.468; power Doppler ultrasonography: P=0.045, correlation coefficient =0.507). On the receiver operating characteristic curve analysis, the sensitivity and specificity for predicting synovitis were 83.2% and 92.7%, respectively, for joint SUV and 81.5% and 90.7%, respectively, for joint-to-bone uptake ratio. Moreover, the summation of both PET/CT parameters of 28 joints showed a diagnostic accuracy of 100.0% for predicting high disease activity in rheumatoid arthritis.

Conclusions

Summed joint uptake on F-18 NaF PET/CT had a strong positive correlation with DAS28-ESR and accurately predicted high disease activity. F-18 NaF PET/CT parameters might be used as an imaging biomarker for disease activity in rheumatoid arthritis.

Trial registration

This study was registered at the Clinical Research Information Service of the Korea (CRIS, http://cris.nih.go.kr/cris/en; registry number, KCT0002597; registered November 2017).

Doppler ultrasound predicts successful discontinuation of biological DMARDs in rheumatoid arthritis patients in clinical remission

OBJECTIVE

To assess the ability of ultrasound to predict successful tapering and successful discontinuation of biological disease-modifying anti-rheumatic drugs (bDMARDs) at 2-year follow-up in rheumatoid arthritis (RA) patients in sustained remission.

METHODS

Patients in sustained remission (DAS28-CRP≤2.6) and no radiographic progression the previous year tapered bDMARD according to a standardized regime. One-hundred-and-nineteen of these patients were included in this ultrasound sub-study. At baseline, clinical assessment, MRI, x-ray and ultrasound of 24 joints were performed. Ultrasound-detected synovitis was defined and scored 0-3 using the Outcome in Rheumatology (OMERACT) scoring system at joint level for both greyscale and Doppler activity. Sum scores for each ultrasound modality were calculated for 24 joints at patient level. Final state of treatment was assessed after 2 years. The predictive value of ultrasound measures for successful tapering and discontinuation at 2-year follow-up was assessed via logistic regression analyses.

RESULTS

Negative IgM-RF (OR = 0.29; 95% Confidence Interval (CI)=0.10-0.85; p = 0.024) and lower Doppler sum score of 24 joints (OR(95%CI)=0.44;(0.15-0.87); p = 0.014) were independent predictors for successful discontinuation of bDMARD at 2-year follow-up. The predictive value of Doppler sum score was independent of MRI findings. Previous numbers of bDMARDs were predictive of successful tapering (OR(95% CI)=0.58(0.35-0.91); p = 0.018), whereas ultrasound was not. Clinical parameters were not predictive for successful tapering/discontinuation.

CONCLUSIONS

Doppler sum score was an independent predictor for successful discontinuation of bDMARDs at 2-year follow-up - the odds for achieving successful discontinuation decreased by 56% per one-unit increase in Doppler sum score. Ultrasound could not predict successful tapering.

Serum Calprotectin is Indicating Clinical and Ultrasonographic Disease Activity in Rheumatoid Arthritis, even with Normal C-Reactive Protein Levels

Objective:

Calprotectin is an inflammatory biomarker which assesses disease activity in rheumatoid arthritis (RA). The objective of this study was to test whether serum calprotectin is associated with clinical and ultrasonographic disease activity in patients with RA, and to analyse its predicting value for disease activity evaluation despite normal C-Reactive protein (CRP) levels.

Methods:

We included 80 patients with RA and 30 healthy subjects. Patients were examined clinically and by ultrasound, (US7 score) along with laboratory parameters (calprotectin, CRP, erythrocyte sedimentation rate [ESR]). Disease activity scores (DAS28) were calculated to assess disease activity. Firstly, patients were divided into four subgroups according to the DAS28-ESR (high, moderate, low disease activity, and remission), then into two subgroups; group-1 (DAS-28≤3.2) and group-2 (DAS28>3.2). The predicting value of calprotectin for disease activity in patients with normal CRP was analysed with univariate and multivariate analysis and receiver operating characteristic curves.

Results:

Calprotectin levels were higher in RA patients than controls (96.3±45.9 ng/ml, 54.7±50.0 ng/ml, respectively; p<0.001). Calprotectin levels were 74.8±45.5 ng/ml in group-1 (n=37) and 114.7±37.9 ng/ml in group-2 (n=43) (p<0.001). In univariate analyses, calprotectin was significantly correlated with clinical, laboratory, and ultrasound parameters (p<0.05), and was a better predictor of power doppler synovitis than CRP in multivariate analysis (OR=1.014; 95%CI 1.002–1.027; p=0.024). The discriminatory capacity for calprotectin to distinguish ultrasonographically active disease in patients with normal CRP levels using AUC was 0.75 (95%CI 0.56–0.90, p=0.023).

Conclusions:

Calprotectin represents disease activity, even in patients who are clinical and ultrasonographical active but have normal CRP levels.

Using a DAS28-CRP-steered treat-to-target strategy does not eliminate subclinical inflammation as assessed by ultrasonography in rheumatoid arthritis patients in longstanding clinical remission

Background

Subclinical synovitis by ultrasound is a frequent finding in rheumatoid arthritis (RA) patients in remission and has been shown to be related to erosive progression, risk of flare and unsuccessful drug tapering, but it has not been investigated how a DAS28 T2T-steered strategy in routine care affects the presence of subclinical synovitis in RA patients in remission. The aim of the current study was to investigate the presence of ultrasound-detected subclinical inflammation in RA patients in long-term remission receiving either biological or conventional disease-modifying anti-rheumatic drugs (bDMARD/csDMARD) and, finally, to investigate the presence of ultrasound remission using different ultrasound remission criteria.

Methods

Eighty-seven RA patients (42 patients receiving bDMARD and 45 csDMARD) received DAS28-CRP-steered treatment in routine care and had achieved DAS28-CRP-remission for > 1 year without radiographic progression. Twenty-four joints were scored 0–3 by ultrasound (elbows, wrists, knees, ankles, metacarpophalangeal and metatarsophalangeal joints 2–5) for grey-scale synovial hypertrophy (GS) and colour Doppler activity (CD) using the OMERACT scoring system. Ultrasound remission was defined as strict (GS score = 0 and CD score = 0), semi-strict (GS score < 1 and Doppler score = 0) and Doppler remission (Doppler score = 0).

Results

No differences between treatment groups were found for GS sum score and Doppler sum score (median (range) 6 (0–19) and 0 (0–12), respectively). A Doppler score > 0 in at least 1 joint was seen in 44%, a GS score > 1 in at least 1 joint in 93% and a GS score > 2 in at least 1 joint in 54% of patients. Strict ultrasound remission was only observed in bDMARD patients (7%; p = 0.01). Thirty-seven per cent were in semi-strict ultrasound remission and 56% in Doppler remission (no significant difference between groups) with similar results across the subgroups of patients who also fulfilled the ACR-EULAR Boolean-, CDAI- and SDAI-remission criteria.

Conclusions

Ultrasound frequently detected subclinical synovitis in RA patients in longstanding DAS28-remission obtained through a DAS28-CRP-steered strategy. This was independent of treatment and applied ultrasound remission criteria. Strict ultrasound remission was rare.

Identification, localization and differentiation of erosions and physiological bone channels by ultrasound in rheumatoid arthritis patients

OBJECTIVES

Ultrasound (US) can detect cortical bone lesions in RA. However, not all cortical bone lesions are erosions. Herein, we aimed to define whether US can differentiate between physiological bone channels and pathological erosions in RA and to provide topographic description of their differential localization.

METHODS

RA patients and healthy controls (HC) received US examination of the metacarpophalangeal (MCPJ) and proximal inter-phalangeal (PIPJ) joints adjudicating cortical bone lesions as physiological bone channels or pathological erosions. In a subset of RA patients and HC, high-resolution peripheral quantitative computed tomography (HR-pQCT) of the hand was performed to validate the classification of lesions.

RESULTS

A total of 40 RA patients and 43 HC were enrolled and totally 771 MCPJ and 638 PIPJ were examined by US, and 94 and 51, respectively, by HR-pQCT. US-defined cortical bone lesions clustered in the lateral part of the MCP (50%) and the dorsal part of the PIPJ (66.7%) in RA. US-defined physiological bone channels clustered in the palmar parts of the MCPJ and PIPJ in both RA (78.8% and 100%, respectively) and HC (51.8% and 80%, respectively). HR-pQCT data confirmed US data with respect to adjudication of physiological bone channels and pathological erosions. Erosions were significantly (all P <0.000001) larger than physiological channels and preferentially localized at radial and ulnar sites, while physiological channels were clustered at palmar sites. Specificity of US was excellent for erosions in RA and for physiological bone channels in HC and RA.

CONCLUSION

US allows differentiation between physiological channels and bone erosions in RA.

A retrospective analysis of the relationship between anti-cyclic citrullinated peptide antibody and the effectiveness of abatacept in rheumatoid arthritis patients

This study aimed to evaluate the effectiveness of abatacept (ABA) by anti-cyclic citrullinated peptide (ACPA) status on disease activity as well as radiographic progression in patients with rheumatoid arthritis (RA) in clinical settings. A retrospective cohort study was conducted using data from a multicenter registry. Data from a total of 553 consecutive RA patients treated with intravenous ABA were included. We primarily compared the status of disease activity (SDAI) and radiographic progression (van der Heijde modified total Sharp score: mTSS) between the ACPA-negative (N = 107) and ACPA-positive (N = 446) groups. 'ACPA positive' was defined as ≥ 13.5 U/mL of anti-CCP antibody. Baseline characteristics between groups were similar. The proportion of patients who achieved low disease activity (LDA; SDAI ≤ 11) at 52 weeks was significantly higher in the ACPA-positive group. Multivariate logistic regression analysis identified ACPA positivity as an independent predictor for achievement of LDA at 52 weeks. Drug retention rate at 52 weeks estimated by the Kaplan-Meier curve was significantly higher in the ACPA-positive group. Achievement rate of structural remission (ΔmTSS ≤ 0.5) at 52 weeks was similar between groups. ABA treatment demonstrated a significantly higher clinical response and higher drug retention rate in ACPA-positive patients. Progression of joint destruction was similar between the ACPA-negative and ACPA-positive groups. Close attention should be paid to joint destruction even in patients showing a favorable response to ABA, especially when the ACPA status is positive.

Synovitis in rheumatoid arthritis detected by grey scale ultrasound predicts the development of erosions over the next three years

Objectives

To evaluate grey scale US (GSUS) and power Doppler US synovitis (PDUS), separately or in combination (CombUS), to predict joint damage progression in RA.

Methods

In this cohort study nested in the Swiss RA register, all patients with sequential hand radiographs at their first US assessment were included. We analysed the summations of semi-quantitative GSUS, PDUS and CombUS assessments of both wrists and 16 finger joints (maximum 54 points) at their upper limit of normal, their 50th, 75th or 87.5th percentiles for the progression of joint damage (ΔXray). We adjusted for clinical disease activity measures at baseline, the use of biological DMARDs and other confounders.

Results

After a median of 35 months, 69 of 250 patients with CombUS (28%), 73 of 259 patients with PDUS (28%) and 75 of 287 patients with available GSUS data (26%) demonstrated joint damage progression. PDUS beyond upper limit of normal (1/54), GSUS and CombUS each at their 50th (9/54 and 10/54) and their 75th percentiles (14/54 and 15/54) were significantly associated with ΔXray in crude and adjusted models. In subgroup analyses, GSUS beyond 14/54 and CombUS higher than 15/54 remained significantly associated with ΔXray in patients on biological DMARDs, while clinical disease activity measures had no significant prognostic power in this subgroup.

Conclusion

Higher levels of GSUS and CombUS are associated with the development of erosions. GSUS appears to be an essential component of synovitis assessment and an independent predictor of joint damage progression in patients on biological DMARDs.

The Role of Musculoskeletal Ultrasound Imaging in Rheumatoid Arthritis

Musculoskeletal ultrasound (MSUS) is gaining popularity among rheumatologists, especially in the context of rheumatoid arthritis (RA) joint assessment, as it is a non-invasive, radiation-free imaging modality that is relatively easy to set up in a clinic setting. Although ultrasonography (US) is often regarded as being operator dependent with associated reproducibility issues, the use of consensus-based scoring system along with standardized definition of joint inflammation in RA has been shown to improve its performance/reliability as an outcome measurement tool. Through this review article, we have (i) gone through the principle US findings in RA joint assessment, (ii) discussed various scoring systems for evaluation of US joint pathologies, (iii) described the literature in the use of US in areas of RA diagnosis and disease prognostication and (iv) examined the findings of recent major randomized controlled trials incorporating US as monitoring tools to help target treatment in RA. By doing so, we hope to provide clinicians with an insight into the role of musculoskeletal US imaging in areas of RA diagnosis, prognosis and disease monitoring.

Contributing factors of clinical outcomes at 1 year post-diagnosis in early rheumatoid arthritis patients with tightly controlled disease activity in clinical practice: a retrospective study

OBJECTIVES

To determine whether specific parameters contribute to clinical outcomes at 1 year post-diagnosis in early rheumatoid arthritis (RA) patients under the 'treat-to-target' strategy in clinical practice.

METHODS

We retrospectively analyzed 125 RA patients selected according to the following criteria; the patients' symptom duration was ≤6 months, and none had experience with DMARDs. We evaluated the patients' clinical disease activity at baseline and 1 year of treatment and the musculoskeletal ultrasound (MSUS)-detected synovitis activity at baseline. We performed an analysis to identify parameters that contribute to SDAI remission and the use of biologic/targeted synthetic (b/ts) DMARDs at 1 year post-diagnosis.

RESULTS

Forty-seven patients received b/tsDMARDs therapy, and 58 patients achieved SDAI remission at 1 year post-diagnosis. Rheumatoid factor positivity, low patient's/evaluator's global assessment at baseline, and methotrexate use at 1 year post-diagnosis were associated with SDAI remission. The baseline clinical disease activity and MSUS scores were not associated with SDAI remission. Anti-cyclic citrullinated peptide antibody positivity/high titer and high swollen joint counts or the presence of severe synovial hypertrophy at baseline were associated with the use of b/tsDMARDs therapy.

CONCLUSION

The value of the expected poor-prognosis factors may be diminished by intensive therapy within the 'windows of opportunity'.

Doubtful swelling on clinical examination reflects synovitis in rheumatoid arthritis

Aims

The aim of this study was to evaluate the implication of doubtful joint swelling on clinical examination with respect to objective markers of synovitis by ultrasound (US) in patients with rheumatoid arthritis (RA).

Methods

Two independent observers performed a modified 28 swollen joint assessment (28SJC), in which joints could be graded as either definitely swollen, non-swollen, or doubtfully swollen. Two examiners blinded to clinical information performed US assessment of the hands. We performed descriptive statistics and models to analyse the links between clinical assessment and objective markers of inflammation.

Results

A total of 1204 joints were evaluated in 43 RA patients; 93% (40/43) of patients had ⩾1 joint with doubtful swelling (range: 0-4/patient). Inter-reader reliability for the modified 28SJC was good (0.74). Generally, both grey scale (GS) and power Doppler (PD) discriminated across not swollen, doubtful, and swollen joints. GS signals discriminated better than PD between doubtful swelling and no swelling [odds ratio (OR) for GS: 5.2; 95% confidence interval (CI) 1.2-23.3 versus OR for PD 1.7; 95% CI 0.2-13.0], whereas PD discriminated better than GS between swelling and doubtful swelling (OR for PD: 28.7; 95% CI 3.6-228.2 versus GS: 1.7; 95% CI 0.3-8.4). Joint osteophytes did not increase the degree of doubtfulness.

Conclusion

Clinical doubt in the assessment of joint swelling constitutes an intermediate state between unequivocal swelling and the lack thereof also regarding the objectively quantified level of inflammation. In order to increase sensitivity for joint inflammation, the historical clinical approach of considering doubtful swelling the absence of swelling should be revisited to interpret clinical doubtfulness as an indication of swelling.

Intensive therapy alleviates subclinical synovitis on ultrasound and disease activity and reduces flare in rheumatoid arthritis patients who have achieved clinical target - a randomized controlled trial

OBJECTIVE

Whether intensive therapy can alleviate subclinical synovitis and reduce flare in rheumatoid arthritis (RA) patients in clinical remission remains unclear. We designed a 1-year open-labelled, randomized controlled clinical trial to elucidate this question.

METHODS

RA patients in clinical remission/low disease activity (defined by DAS28-CRP≤ 3.2), however with subclinical synovitis on ultrasound [power Doppler (PD)≥1 and/or gray scale (GS)≥2] were randomized to receive maintenance or intensive treatment at a ratio of 1:1. The primary outcome was the rate of RA relapse (defined by DAS28-CRP>3.2 and an increase≥0.6). The secondary outcomes were changes of PD and GS scores, and clinical disease activity at each visit from baseline.

RESULTS

108 patients with 54 in each group were enrolled. During 1-year follow-up, the relapse rate was significantly higher in maintenance group than in intensive group, regardless of all enrolled patients or those in remission [24.1% (13/54) vs. 9.1% (5/54), p=0.039; 26.2% (11/42) vs. 5.3% (2/38), p=0.026, respectively]. Although GS and PD scores were decreased at 12 months in both groups, the decline was more remarkable in intensive group than in maintenance group. The improvement of clinical disease activity score was only observed in intensive group, not maintenance group. Adverse events were comparable between two groups. Abnormal liver function tests were observed in 24 (22%) patients with 16 from intensive group.

CONCLUSION

Intensive therapy can alleviate subclinical synovitis on ultrasound and clinical disease activity, and prevent relapse in RA patients who have achieved clinical remission or low disease activity, with comparable safety profiles to maintenance therapy.

REGISTRATION NUMBER

ChiCTR2000029279.

Treat-to-target strategies aiming at additional ultrasound remission is associated with better control of disease activity and less flare in rheumatoid arthritis

INTRODUCTION

Treat-to-target (T2T) strategy has greatly improved the prognosis of rheumatoid arthritis (RA). However, the additional benefit of targeting ultrasound (US) remission in addition to clinical remission has been debated.

METHODS

RA patients in clinical remission or low disease activity were enrolled. They were assorted into two groups according to the principle of T2T strategy adopted. In clinical group, treatment decision was made with the aim of maintaining DAS28(ESR) ≤ 3.2 only, while in clinical US group, the aim was to attain total power Doppler (PD) US score = 0 in addition to DAS28(ESR) ≤ 3.2. The time-averaged DAS28, flare, and changes of treatment strategy were compared.

RESULTS

One hundred ninety-four patients completed 1-year follow-up, with 100 in clinical US and 94 in clinical group. Compared to clinical group, time-averaged DAS28 in clinical US group was significantly lower (1.89 ± 0.51 vs. 2.33 ± 0.71, P < 0.01) with less flare (20.0% vs. 36.2%, P < 0.05). Furthermore, at the end of 1 year, significantly more patients successfully achieved step-down therapy (66.0% vs. 44.7%, P < 0.01) and dramatically fewer patients with step-up therapy in the clinical US group (13.0% vs. 25.5%, P < 0.05) compared to clinical group. In clinical US group, baseline DAS28(ESR) > 2.29, presence of subclinical synovitis, and step-down strategy were independent risk factors for relapse after clinical remission or low disease activity was achieved.

CONCLUSIONS

An US-driven T2T in addition to current clinical remission strategy is associated with better control of the disease activity, reduction of relapse, as well as long-term step-down therapy. Step-down strategy should be carefully applied to the patients with baseline DAS28(ESR) over 2.29 and presence of subclinical synovitis even after they have achieved clinical remission or low disease activity. Key Points • Targeting ultrasound remission in addition to current T2T strategy is associated with a better control of RA. • Step-down strategy should be cautiously considered in those with DAS28(ESR) > 2.29 and baseline subclinical synovitis after they have achieved clinical remission or low disease activity.

Angiogenic cytokines can reflect the synovitis severity and treatment response to biologics in rheumatoid arthritis

Angiogenesis and synoviocyte hyperplasia, called 'pannus,' are pathologic hallmarks of rheumatoid arthritis (RA). To determine the clinical significance of angiogenic cytokines in RA, the levels of pro-angiogenic cytokines, including VEGF, placenta growth factor (PlGF), and IL-6, were measured in the synovial fluid (SF, n = 54) and sera of RA patients (n = 157) using ELISA. Patients (n = 103) with disease activity score 28 (DAS28) > 3.2, which indicates moderate to high RA activity, underwent follow-up blood sampling at 6 months after treatment with conventional disease-modifying anti-rheumatic drugs (c-DMARD) or biologic DMARD (b-DMARD) including an anti-TNFα antibody, an anti-IL-6 antibody, and abatacept. Ultrasonography (US) was performed on affected joints to define the synovitis severity at the time of sampling. Consequently, in the SF of RA patients, PlGF and IL-6 levels correlated well with synovitis severity determined by US. In RA sera, VEGF and IL-6 levels were elevated in proportion to synovitis severity, correlating with conventional markers for disease activity, including ESR, CRP, and DAS28. In c-DMARD users (n = 53), serially monitored levels of serum VEGF, IL-6, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) all decreased in good and moderate responders but not in nonresponders. In b-DMARD users (n = 49), only serum VEGF well represented the treatment response, while CRP nonspecifically decreased irrespective of the treatment outcome. By multivariable analysis, serum ΔVEGF, but not ΔESR or ΔCRP, was an independent factor associated with good and moderate responses to DMARD. In summary, the angiogenic cytokines PlGF and VEGF represent the synovitis severity of RA assessed by US. In patients receiving b-DMARD, serum VEGF may be more valuable than CRP in reflecting the treatment response.

Severe joint deformity and patient global assessment of disease are associated with discrepancies between sonographic and clinical remission: A cross-sectional study of rheumatoid arthritis patients

OBJECTIVE

Although recent clinical trials showed that ultrasound (US) remission is not required to achieve good outcomes at the group level, it currently remains unclear whether the prognosis of individual patients in clinical remission, but not US remission, i.e. those with subclinical sonographic synovitis (SSS), is favorable. However, it is no longer acceptable to perform US on all patients in order to identify those with SSS. Therefore, the present study was initiated to elucidate the conditions under which SSS is frequently detected.

METHODS

In total, 563 consecutive RA patients were recruited. Bilateral 2-5 MCP, wrist, ankle, and 2-5 MTP joints were scanned by US, and Gray scale and Power Doppler (PD) images were scored semi-quantitatively. Clinical data were obtained by physicians who were blind to US results. Changes in the modified Total Sharp Score (mTSS) of tocilizumab (TCZ) users were calculated.

RESULTS

A total of 402 patients were included. SSS was more frequently detected in patients with more severe joint deformity, even if they were in remission. In contrast, a high Patient Global Assessment of Disease (PtGA) did not reflect SSS. Furthermore, the relationship between PtGA and PD scores was weak. Although the frequency of SSS was high in TCZ user, the presence of SSS in TCZ users not always results in the progression of mTSS.

CONCLUSIONS

While remission is overestimated in patients with severe joint deformity, underestimations may occur in those who do not fulfill remission criteria because of a high PtGA.

Subclinical Treatment Targets in Rheumatology: Lessons from Randomized Clinical Trials in Rheumatoid Arthritis

In treat-to-target strategies, choosing the correct target is fundamental to success. The target should be associated with future good outcomes for the patient. Most rheumatic diseases are characterized by inflammation, affecting different tissues depending on the condition. Low-grade, subclinical inflammation is by definition not apparent on clinical examination, but may have significant long-term consequences for the individual. It has thus been debated whether targeting subclinical inflammation would improve long-term outcomes in rheumatoid arthritis. The authors use rheumatoid arthritis as an example to describe and discuss the status of subclinical targets in treat-to-target strategies within rheumatology.

The role of ultrasound and magnetic resonance imaging for treat to target in rheumatoid arthritis and psoriatic arthritis

The treat-to-target (T2T) approach has revolutionized the way we treat patients with rheumatic and musculoskeletal diseases. Recent attention has focused on imaging techniques, in particular musculoskeletal ultrasound and MRI as a focus for T2T strategies. Recently, a number of randomized clinical trials have been performed that compared tight clinical control vs control augmented by imaging techniques. While the three published trials have concluded that imaging does not add to tight clinical care, implementing imaging into the T2T strategy has actual advantages, such as the detection of subclinical involvement, and information on joint involvement/pathology and may possess potential advantages as evidenced by certain secondary endpoints. This review examines the findings of these studies and discusses the advantages and disadvantages of incorporating imaging into the T2T strategy.

Serial magnetic resonance imaging and ultrasound examinations demonstrate differential inflammatory lesion patterns in soft tissue and bone upon patient-reported flares in rheumatoid arthritis

BACKGROUND

Magnetic resonance imaging (MRI) and ultrasonography (US) are more sensitive than clinical evaluation in assessing inflammation in rheumatoid arthritis (RA). Data is scarce regarding potential link between patient-reported flares and inflammation on imaging. The aim of the study was to explore the pattern and longitudinal associations of inflammatory lesions detected by serial MRI and US in relation to patient-reported flares in patients with RA.

METHODS

Eighty RA patients with baseline DAS28CRP < 3.2 and no swollen joints were examined at baseline and followed for 1 year. Patients were requested to contact the hospital in case of patient-reported hand flare accompanied by ≥ 1 tender and swollen joint. The 29 patients who reported hand flare had four extra visits within 4 months from flare onset comprising clinical examination, patient-reported outcomes, MRI, and US of wrists and hands. MRI synovitis/tenosynovitis/bone marrow edema (BME) and US synovitis/tenosynovitis were scored. MRI and US scores at and after the flare were compared to baseline before the flare, and associations were explored by linear mixed models for repeated measurements.

RESULTS

Synovitis and tenosynovitis by MRI/US increased significantly at flare onset. Synovitis waned quickly, as did US tenosynovitis. BME showed delayed increase yet persisted, once the patient-reported flare had resolved, as did MRI tenosynovitis. In univariate models, patient-reported flares were associated with all MRI and US inflammatory markers, except for BME, which was only associated with SJC28 and long-lasting flares > 14 days. Independent associations were observed between patient-reported flares and tenosynovitis by MRI and US (p < 0.05).

CONCLUSIONS

Patient-reported flares were linked to inflammation detected by serial MRI and US. Differential patterns of inflammatory lesion evolution were observed by serial imaging with early synovial and tenosynovial inflammation, followed by delayed-onset BME.

Characterization of a Subset of Patients With Rheumatoid Arthritis for Whom Current Management Strategies are Inadequate

Objective

A subset of patients with seropositive rheumatoid arthritis (RA) do not mount a C‐reactive protein (CRP) response during flares. We hypothesize that these patients are more likely to experience poor clinical care and less likely to respond to traditional therapy. This study questioned whether this presentation was associated with worse disease outcome and distinct immunological features.

Methods

Using Power Doppler ultrasound, 48 RA patients with active synovitis were recruited; 30 had normal (n)CRP (5 mg/L or less) and 18 had high (h)CRP (more than 5 mg/L) levels. All had equivalent disease burden assessed by other clinical and laboratory parameters.

Results

Time to diagnosis and time to first disease‐modifying antirheumatic drug were significantly longer in nCRP compared with hCRP patients (P < 0.05). Significantly more nCRP patients needed escalation to biologics after 2‐year follow‐up (P = 0.01). The inflammatory milieu was also different between the two subgroups. Synergy between inflammatory cytokines observed in hCRP patients was lost in nCRP patients, and nCRP patients had significantly increased regulatory T‐cell (Treg) frequencies that correlated positively with predictors of poor disease outcome. Conversely, hCRP but not nCRP patients demonstrated a significant upregulation of alternative complement pathway factors that correlated negatively with Treg frequency.

Conclusion

Patients with nCRP during flares of RA had an altered immunological profile compared with hCRP patients and experienced diagnostic delays and responded less favorably to conventional treatment.

Predominant ultrasonographic extracapsular changes in symptomatic psoriatic dactylitis: results from a multicenter cross-sectional study comparing symptomatic and asymptomatic hand dactylitis

OBJECTIVE

Despite diffuse digital swelling, dactylitis may sometimes be asymptomatic. The objective of this study was to compare the clinical and ultrasonographic features of symptomatic with asymptomatic psoriatic arthritis (PsA) dactylitis.

METHODS

One hundred and twenty-five hand dactylitis were evaluated in a multicenter cross-sectional study for the presence of pain, subjective functional limitation, and tenderness (4-points scale) with the calculation of a Leeds Dactylitis Index (LDI) score. Fingers were subsequently investigated using high-frequency ultrasound (US) both in gray-scale (GS) and power Doppler (PD), for the presence and grading of flexor tenosynovitis, soft tissue edema, subcutaneous PD signal (PDUS), extensor tendon involvement, and joints synovitis. Clinical and US characteristics of symptomatic dactylitic fingers were compared with the asymptomatic dactylitic ones.

RESULTS

Symptomatic fingers (n = 80) had a significantly lower dactylitis duration compared to asymptomatic fingers (n = 36) (p < 0.001). Values of LDI, patient VAS-pain, and VAS-functional score were significantly higher in fingers with symptomatic dactylitis (p < 0.001 and p = 0.010, respectively). Symptomatic dactylitis had a higher prevalence of flexor tenosynovitis of grade > 2, soft tissue edema and subcutaneous PDUS signal (p < 0.001). Asymptomatic dactylitis showed a greater prevalence of joint synovitis (both in GS and in PD) than symptomatic dactylitis (p < 0.001).

CONCLUSIONS

Digital tenderness and pain are linked to US tenosynovitis of grade > 2 and extra synovial abnormalities and conversely asymptomatic dactylitis is associated with joint-based synovitis.Key Points• Digital tenderness and local pain in psoriatic arthritis dactylitis are strongly associated with flexor tenosynovitis of grade> 2, soft tissue edema, and subcutaneous PD signal.• In psoriatic arthritis, asymptomatic dactylitis showed a greater prevalence of joint synovitis than symptomatic dactylitis.• In psoriatic arthritis, ultrasound inflammatory abnormalities are present in about 70% of cold dactylitis which is linked for disease chronicity.• In psoriatic arthritis, the flexor tendon and adjacent soft tissues play a significant role in symptomatic dactylitis.

Detecting inflammation in rheumatoid arthritis using Fourier transform analysis of dorsal optical transmission images from a pilot study

A clinical need exists for low-cost and noninvasive imaging tools capable of detecting inflammation in the joints of inflammatory arthritis patients. Previous studies have reported an optical contrast between inflamed and noninflamed joints resulting from distinct absorption and scattering properties. Accurate classification using nonocclusion-based continuous wave, transillumination imaging was limited to patient-specific changes during follow-up examination as opposed to single time-point examination, which was attributed to high intersubject variability. In distinction from previous work, optical images were acquired from the dorsal side with illumination on the palmar side and features about the spatial distribution of transmitted light along the joint were assessed using a normalized Fourier transform method. Results using this approach demonstrated an area under receiver operator curve of up to 0.888 for detecting inflammation in a pilot study involving single time-point examination of 144 joints from 21 rheumatology patients. This workflow may enable future development of clinically viable, low-cost devices for assessing inflammation in arthritis patients, without the need for cuff occlusion or comparison to baseline.

MR and ultrasound of the hands and wrists in rheumatoid arthritis. Part II. Added clinical value

Advanced imaging has become just as vital for diagnosing, staging, and monitoring disease in rheumatoid arthritis (RA) patients as it is for cancer patients. Part 1 of this review discussed synovitis, tenosynovitis, erosions, and osteitis-key imaging findings that occur in patients with RA. Part 2 will now show how these features, in combination with clinical and serologic data, can assist clinical decision-making at various stages of a patient's disease course. Specifically, assessing current disease activity and prognosticating future aggressiveness inform treatment decisions at initial presentation, during medical treatment, and at clinical remission. In addition to summarizing the current literature on advanced imaging in RA, clinical examples from different stages throughout the disease course will illustrate practical approaches for applying these research results. Last, this review will describe potential future roles of imaging in RA patients.

The agreement between ultrasound-determined joint inflammation and clinical signs in patients with rheumatoid arthritis

Background

Ultrasound (US) is sensitive for detecting joint and tendon inflammation in patients with rheumatoid arthritis (RA). So far, which grade of abnormalities on US corresponds to clinical manifestations is unclear. This study aimed to investigate the agreement between US-detected joint inflammation and clinical signs (joint swelling and tenderness).

Methods

In this cross-sectional study, 22 joints of the wrists and hands were, respectively, evaluated by physical examination (PE) and ultrasound in RA patients. Gray scale (GS) and power Doppler (PD) of synovitis, detected by ultrasound, were graded by semi-quantitative scoring systems (0–3). Tenosynovitis and peritendinitis were assessed qualitatively (0/1).

Results

A total of 258 consecutive RA patients were included, with median disease duration of 57 months and mean Disease Activity Score based on 28 joints (DAS28)-ESR/DAS28-CRP of 4.47/3.99. In a total of 5676 joints assessed, the overall concordance rate between positive clinical signs and ultrasound-determined joint inflammation was fair (κ = 0.365, p < 0.01). In wrists, joint tenderness showed higher κ coefficient (κ = 0.329, p < 0.01) with ultrasound-determined joint inflammation than swelling (κ = 0.263, p < 0.01); however, swelling showed higher κ coefficient (κ = 0.156–0.536, p < 0.01) with ultrasound-determined joint inflammation than tenderness (κ = 0.061–0.355, p < 0.01) in metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. Synovitis had consistently higher agreement with tenderness and swelling than tenosynovitis/peritendinitis. Tenderness and swelling had the highest κ coefficient with GS ≥ 1 synovial hyperplasia in most MCP and PIP joints, while with GS ≥ 2 synovial hyperplasia in wrists. For all 22 joints, PD ≥ 1 synovitis had the highest κ coefficient with clinical tenderness and swelling.

Conclusions

Synovitis had better agreement with clinical signs than tenosynovitis/peritendinitis. Joint swelling showed better agreement with US-determined inflammation than tenderness for MCP and PIP joints, while the opposite for wrists. Both tenderness and swelling are more likely to correspond to GS ≥ 2 for wrists, GS ≥ 1 for MCP and PIP joints, and PD ≥ 1 for any joint.

Detection of subclinical synovial hypertrophy by musculoskeletal gray-scale/ power Doppler ultrasonography in systemic lupus erythematosus patients: A cross-sectional study

OBJECTIVE

Laboratory investigations are invasive methods. Magnetic resonance imaging (MRI) has a small field of view. Ultrasound can be performed at multiple parts of the body. The objective of the study was to find out subclinical synovial hypertrophy in systemic lupus erythematosus patients using gray-scale/power Doppler ultrasonography.

METHODS

A total of 247 systemic lupus erythematosus (without musculoskeletal involvement) patients from 21 February 2017 to 28 October 2018 were included in the cross-sectional study. Patients were subjected to physical examinations, laboratory tests, and gray-scale/power Doppler ultrasonography examinations. Synovial hypertrophy was confirmed if it was present in at least 4 out of 100 of the examined location sites. MRI examinations were performed for confirmation purposes. Spearman correlation was performed between imaging and laboratory investigations at the 99% confidence level.

RESULTS

No correlation was observed for results of synovial hypertrophy between physical examinations/laboratory tests and gray-scale/power Doppler ultrasonography examinations except erythrocyte sedimentation rate (r = 0.354). Cost of laboratory tests (315.47 ± 19.15 ¥/person) for subclinical synovial hypertrophy detection was higher than that of gray-scale/power Doppler ultrasonography examinations (135.47 ± 8.17 ¥/person, P <0.0001, q = 230.87). Results of gray-scale/power Doppler ultrasonography have a correlation with results of MRI (r = 0.34).

CONCLUSION

Only perform gray-scale/power Doppler ultrasonography examinations for regular maintenance of rheumatologic disease in systemic lupus erythematosus patients.

Clinical outcomes of patients with active rheumatoid arthritis with normal acute phase reactant values

AIM

Despite high clinical disease activity, some patients with active rheumatoid arthritis (RA) have normal acute phase reactant (APR) values. This study aimed to determine the clinical outcomes of active RA patients with normal APR values.

METHOD

Of 5376 patients with RA enrolled in the Korean observational study network for arthritis (KORONA) registry, 400 patients with disease duration of <2 years who had Clinical Disease Activity Index (CDAI) score of >2.8 at baseline, biologic-naïve, and erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) drawn at both baseline and 2-year follow-up visits were identified. Patients were grouped according to baseline APR levels: normal APRs, one APR elevated, and both APRs elevated.

RESULTS

Baseline tender and swollen joint counts, mean CDAI and Health Assessment Questionnaire-Disability Index (HAQ-DI) scores were significantly lower in the normal APRs group compared with APR-elevated groups (P < 0.0001). At 2-year follow-up, mean CDAI scores, HAQ-DI, and percentage of the patient achieving remission were not significantly different between the normal APRs group compared with the APR-elevated groups regardless of the baseline disease activity. However, in patients with baseline CDAI moderate to high disease activity, the normal APRs group less frequently required initiation of the biologic disease-modifying anti-rheumatic drugs compared with the APR-elevated groups (P = 0.044).

CONCLUSION

Active RA patients with normal APR values have milder disease presentation, but similar clinical outcomes to those with elevated APRs.