Early identification of rheumatoid arthritis: does it induce treatment-related cost savings?

OBJECTIVE: Early diagnosis and treatment-start is key for rheumatoid arthritis (RA), but the economic effect of an early versus a later diagnosis has never been investigated. We aimed to investigate whether early diagnosis of RA is associated with lower treatment-related costs compared with later diagnosis. METHODS: Patients with RA consecutively included in the Leiden Early Arthritis Clinic between 2011 and 2017 were studied (n=431). Symptom duration was defined as the time between symptom onset and first presentation at the outpatient clinic; early treatment start was defined as symptom duration <12 weeks. Information on disease-modifying anti-rheumatic drug use per patient over 5 years was obtained from prescription data from patient records. Prices were used from 2022 and 2012 (proxy of time of prescription) to study the impact of changes in drug costs. Autoantibody-positive and autoantibody-negative RA were studied separately because differences in disease severity may influence costs. RESULTS: Within autoantibody-negative RA, costs were 316% higher in the late compared with the early group (ß=4.16 (95% CI 1.57 to 11.1); €4856 vs €1159). When using 2012 prices, results were similar. For autoantibody-positive RA, costs were 19% higher in the late group (€9418 vs €7934, ß=1.19, 0.57 to 2.47). This effect was present but smaller when using 2012 prices. Within patients with autoantibody-positive RA using biologicals, late treatment start was associated with 46% higher costs (ß=1.46 (0.91 to 2.33)); higher costs were also seen when using 2012 prices. CONCLUSION: When RA is detected within 12 weeks after symptom onset, treatment-related costs were lower in both autoantibody-negative and autoantibody-positive RA. This study is the first to report how early diagnosis and treatment start impact treatment-related costs.

EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2023 update.

OBJECTIVE: New modes of action and more data on the efficacy and safety of existing drugs in psoriatic arthritis (PsA) required an update of the EULAR 2019 recommendations for the pharmacological treatment of PsA. METHODS: Following EULAR standardised operating procedures, the process included a systematic literature review and a consensus meeting of 36 international experts in April 2023. Levels of evidence and grades of recommendations were determined. RESULTS: The updated recommendations comprise 7 overarching principles and 11 recommendations, and provide a treatment strategy for pharmacological therapies. Non-steroidal anti-inflammatory drugs should be used in monotherapy only for mild PsA and in the short term; oral glucocorticoids are not recommended. In patients with peripheral arthritis, rapid initiation of conventional synthetic disease-modifying antirheumatic drugs is recommended and methotrexate preferred. If the treatment target is not achieved with this strategy, a biological disease-modifying antirheumatic drug (bDMARD) should be initiated, without preference among modes of action. Relevant skin psoriasis should orient towards bDMARDs targeting interleukin (IL)-23p40, IL-23p19, IL-17A and IL-17A/F inhibitors. In case of predominant axial or entheseal disease, an algorithm is also proposed. Use of Janus kinase inhibitors is proposed primarily after bDMARD failure, taking relevant risk factors into account, or in case bDMARDs are not an appropriate choice. Inflammatory bowel disease and uveitis, if present, should influence drug choices, with monoclonal tumour necrosis factor inhibitors proposed. Drug switches and tapering in sustained remission are also addressed. CONCLUSION: These updated recommendations integrate all currently available drugs in a practical and progressive approach, which will be helpful in the pharmacological management of PsA.

Improving our understanding of the paradoxical protective effect of obesity on radiographic damage: a large magnetic resonance imaging-study in early arthritis.

OBJECTIVE: Obesity conveys a risk for RA development, while paradoxically, associating with less radiographic progression after RA diagnosis. Using MRI we can study this surprising association in detail from MRI-detected synovitis and osteitis to MRI-detected erosive progression, which precedes radiographic progression. Previous research suggested obesity associates with less osteitis and synovitis. We therefore aimed to (i) validate the previously suggested association between BMI and MRI-detected osteitis/synovitis; (ii) study whether this is specific for ACPA-positive or ACPA-negative RA or also present in other arthritides; (iii) study whether MRI-detected osteitis associates with MRI-detected erosive progression; and (iv) study whether obesity associates with MRI-detected erosive progression. METHODS: We studied 1029 early arthritis patients (454 RA, 575 other arthritides), consecutively included in Leiden Early Arthritis Clinic. At baseline patients underwent hand-and-foot MRI that were RAMRIS-scored, and 149 RA patients underwent follow-up MRIs. We studied associations between baseline BMI and MRI-detected osteitis/synovitis (using linear regression), and erosive progression (using Poisson mixed models). RESULTS: In RA, higher BMI associated with less osteitis at disease onset (ß = 0.94; 95% CI: 0.93, 0.96) but not with synovitis. Higher BMI associated with less osteitis in ACPA-positive RA (ß = 0.95; 95% CI: 0.93, 0.97), ACPA-negative RA (ß = 0.97; 95% CI: 0.95, 0.99) and other arthritides (ß = 0.98; 95% CI: 0.96, 0.99). Over 2 years, overweight and obesity associated with less MRI-detected erosive progression (P = 0.02 and 0.03, respectively). Osteitis also associated with erosive progression over 2 years (P < 0.001). CONCLUSIONS: High BMI relates to less osteitis at disease onset, which is not confined to RA. Within RA, high BMI and less osteitis associated with less MRI-detected erosive progression. This suggests that the protective effect of obesity on radiographic progression is exerted via a path of less osteitis and subsequently fewer MRI-detected erosions.

Responsiveness and sensitivity of PROMs to change in disease activity status in early and established rheumatoid arthritis.

OBJECTIVES: To determine whether patient reported outcome measures (PROMs) capturing activity limitations, health impact, pain, fatigue and work ability are responsive and sensitive to changes in disease activity status in patients with early and established rheumatoid arthritis (RA). METHODS: All early RA patients (n = 557) from the tREACH-trial and established RA patients (n = 188) from the TARA-trial were included. Both studies were multicentre, single-blinded trials with a treat-to-target management approach. The following PROMs were studied: Health Assessment Questionnaire Disability Index(HAQ-DI), morning stiffness severity, EQ-5D, general health, 36-item short form(SF-36), joint pain, fatigue and productivity loss. Mean changes in PROMs between two consecutive visits were compared with changes in disease activity status(remission, low disease activity and active disease) using linear mixed models and standardised response means. Additionally, the proportion of individual observations that showed an expected PROM response to disease activity status alterations was calculated. RESULTS: HAQ-DI, morning stiffness severity, general health, EQ-5D and joint pain demonstrated responsiveness to improvement or worsening of disease activity status in both early and established RA. SF-36 physical and mental component scale, fatigue and productivity loss did not show this effect in both groups. Across nearly all PROMs, the magnitude of change and the proportion of individual observations that reflect a shift from and to active disease remained low. CONCLUSION: HAQ-DI, morning stiffness severity, EQ-5D, general health and joint pain are responsive to disease activity status alterations on a group level in both early and established RA. For the individual patient the responsiveness of these PROMs is poor. CLINICAL TRIAL REGISTRATION: tREACH trial (www.isrctn.com, ISRCTN26791028) and TARA trial (www.onderzoekmetmensen.nl, NTR2754).

Patient burden and joint-inflammation during development of RA from arthralgia: is it similar in ACPA-positive and ACPA-negative disease?

OBJECTIVES: Anti-citrullinated protein antibody(ACPA)-positive and ACPA-negative rheumatoid arthritis(RA) differ in underlying risk factors but have a similar clinical presentation at RA-diagnosis. It is unknown what the ACPA-associated differences or similarities are during the symptomatic at-risk stage of RA, clinically suspect arthralgia(CSA). To deepen insights into these differences/similarities, we compared the course of symptoms/impairments and subclinical joint-inflammation in the CSA-phase during progression to inflammatory arthritis(IA) or to CSA-resolution. METHODS: 845 CSA-patients were followed for median 24 months; 136 patients developed IA and additional 355/505 patients had resolution of CSA according to rheumatologists. Patient burden (pain/morning stiffness/fatigue/functional disabilities/presenteeism) was assessed at baseline, 4/12/24 months and IA-development. Subclinical joint-inflammation in hands/feet was assessed over time with 1.5 T-MRI. Linear/Poisson mixed models were used. RESULTS: Both in ACPA-positive and ACPA-negative patients, patient burden increased towards IA-development and decreased towards CSA-resolution. However, patient burden was lower in ACPA-positive than ACPA-negative disease on all timepoints. Conversely, subclinical joint-inflammation tended to increase more rapidly during development of ACPA-positive IA (IRR = 1.52,95%CI = 0.94-2.47, p= 0.089), and remained higher over time in ACPA-positive CSA-patients achieving resolution compared with ACPA-negative patients (IRR = 1.52,95%CI = 1.07-2.15, p= 0.018). Although correlation coefficients between changes in patient burden and subclinical joint-inflammation during progression to IA were weak, they were consistently higher in ACPA-positive than ACPA-negative disease, e.g. ρ = 0.29 vs ρ = 0.12 for functional disabilities. CONCLUSION: During RA-development and CSA-resolution, ACPA-positive CSA-patients have lower patient burden, but more subclinical joint-inflammation than ACPA-negative CSA-patients. These data strengthen the notion that the development of ACPA-positive and ACPA-negative RA is pathophysiologically different, and encourage further research on these differences.

The course of cytokine and chemokine gene expression in clinically suspect arthralgia patients during progression to inflammatory arthritis.

OBJECTIVES: Autoantibody responses increase years before the onset of inflammatory arthritis (IA) and are stable during transitioning from clinically suspect arthralgia (CSA) to IA. Cytokine and chemokine levels also increase years before IA onset. However, the course in the at-risk stage of CSA during progression to disease or non-progression is unknown. To increase the understanding of processes mediating disease development, we studied the course of cytokine, chemokine and related receptors gene expression in CSA patients during progression to IA and in CSA patients who ultimately did not develop IA. METHODS: Whole-blood RNA expression of 37 inflammatory cytokines, chemokines and related receptors was determined by dual-colour reverse transcription multiplex ligation-dependent probe amplification in paired samples of CSA patients at CSA onset and either at IA development or after 24 months without IA development. ACPA-positive and ACPA-negative CSA patients developing IA were compared at CSA onset and during progression to IA. Generalised estimating equations tested changes over time. A false discovery rate approach was applied. RESULTS: None of the cytokine/chemokine genes significantly changed in expression between CSA onset and IA development. In CSA patients without IA development, G-CSF expression decreased (P = 0.001), whereas CCR6 and TNIP1 expression increased (P < 0.001 and P = 0.002, respectively) over a 2 year period. Expression levels in ACPA-positive and ACPA-negative CSA patients who developed IA were similar. CONCLUSION: Whole-blood gene expression of assessed cytokines, chemokines and related receptors did not change significantly from CSA to IA development. This suggests that changes in expression of these molecules may not be related to the final process of developing chronicity and may have occurred preceding CSA onset. Changes in gene expression in CSA patients without IA development may provide clues for processes related to resolution.

Ultrasound of the forefeet besides the hands in patients at risk for rheumatoid arthritis: is it worth the effort? A longitudinal cohort study.

OBJECTIVE: Ultrasound (US) can detect subclinical joint-inflammation in patients with clinically suspect arthralgia (CSA), which is valuable as predictor for rheumatoid arthritis (RA) development. In most research protocols both hands and forefeet are scanned, but it is unclear if US of the forefeet has additional value for predicting RA, especially since synovial hypertrophy in MTP-joints of healthy individuals is also common. To explore the possibility to omit scanning of the forefeet we determined if US of the forefeet is of additional predictive value for RA-development in CSA patients. METHODS: CSA patients of two independent cohorts underwent US of the hands and forefeet. We analyzed the association between RA-development and US-positivity for the full US-protocol, the full US-protocol with correction for Gray Scale(GS)-findings in the forefeet of healthy and the protocol without-forefeet. RESULTS: In total, 298 CSA patients were studied. In patients with a positive US, subclinical joint-inflammation was mostly present in the hands (90-86%). Only 10-14% of patients had subclinical joint-inflammation solely in the forefeet. US-positivity was associated with inflammatory arthritis development in both cohorts, with HRs 2.6(95%CI 0.9-7.5) and 3.1(95%CI 1.5-6.4) for the full protocol, 3.1(95%CI 1.3-7.7) and 2.7(95%CI 1.3-5.4) for the full US-protocol with correction, and 3.1(95%CI 1.4-6.9) and 2.8(95%CI 1.4-5.6) without the forefeet. AUROCs were equal across both cohorts. CONCLUSION: The forefeet can be omitted when US is used for the prediction of RA-development in CSA patients. This is due to the finding that subclinical joint-inflammation in the forefeet without concomitant inflammation in the hands is infrequent.

Intervention with methotrexate in patients with arthralgia at risk of rheumatoid arthritis to reduce the development of persistent arthritis and its disease burden (TREAT EARLIER): a randomised, double-blind, placebo-controlled, proof-of-concept trial.

BACKGROUND: Rheumatoid arthritis is the most common autoimmune disease worldwide and requires long-term treatment to suppress inflammation. Currently, treatment is started when arthritis is clinically apparent. We aimed to evaluate whether earlier intervention, in the preceding phase of arthralgia and subclinical joint inflammation, could prevent the development of clinical arthritis or reduce the disease burden. METHODS: We conducted a randomised, double-blind, placebo-controlled, proof-of-concept-trial at the Leiden University Medical Centre, Leiden, Netherlands. Adults aged 18 years or older with arthralgia clinically suspected of progressing to rheumatoid arthritis and MRI-detected subclinical joint inflammation were eligible for enrolment across 13 rheumatology outpatient clinics in the southwest region of the Netherlands and randomly assigned (1:1) to a single intramuscular glucocorticoid injection (120 mg) and a 1-year course of oral methotrexate (up to 25 mg/week), or placebo (single injection and tablets for 1 year). Participants and investigators were masked to group assignment. Follow-up continued for 1 year after the end of the 1-year treatment period. The primary endpoint was development of clinical arthritis (fulfilling the 2010 rheumatoid arthritis classification criteria or involving two or more joints) that persisted for at least 2 weeks. Patient-reported physical functioning, symptoms, and work productivity were secondary endpoints, which were measured every 4 months. Additionally, the course of MRI-detected inflammation was studied. All participants entered the intention-to-treat analysis. This trial is registered with EudraCT, 2014-004472-35, and the Netherlands Trial Register, NTR4853-trial-NL4599. FINDINGS: Between April 16, 2015, and Sept 11, 2019, 901 patients were assessed for eligibility and 236 were enrolled and randomly assigned to active treatment (n=119) or placebo (n=117). At 2 years, the frequency of the primary endpoint was similar between the groups (23 [19%] of 119 participants in the treatment group vs 21 [18%] of 117 in the placebo group; hazard ratio 0·81, 95% CI 0·45 to 1·48). Physical functioning improved more in the treatment group during the first 4 months and remained better than in the placebo group (mean between-group difference in Health Assessment Questionnaire disability index over 2 years: -0·09, 95% CI -0·16 to -0·03; p=0·0042). Similarly, pain (on scale 0-100, mean between-group difference: -8, 95% CI -12 to -4; p<0·0001), morning stiffness of joints (-12, -16 to -8; p<0·0001), presenteeism (-8%, -13 to -3; p=0·0007), and MRI-detected joint inflammation (-1·4 points, -2·0 to -0·9; p<0·0001) showed sustained improvement in the treatment group compared with the placebo group. The number of serious adverse events was equal in both groups; adverse events were consistent with the known safety profile for methotrexate. INTERPRETATION: Methotrexate, the cornerstone treatment of rheumatoid arthritis, initiated at the pre-arthritis stage of symptoms and subclinical inflammation, did not prevent the development of clinical arthritis, but modified the disease course as shown by sustained improvement in MRI-detected inflammation, related symptoms, and impairments compared with placebo. FUNDING: Dutch Research Council (NWO; Dutch Arthritis Society).

EULAR points to consider for the definition of clinical and imaging features suspicious for progression from psoriasis to psoriatic arthritis.

BACKGROUND: The transition from psoriasis (PsO) to psoriatic arthritis (PsA) and the early diagnosis of PsA is of considerable scientific and clinical interest for the prevention and interception of PsA. OBJECTIVE: To formulate EULAR points to consider (PtC) for the development of data-driven guidance and consensus for clinical trials and clinical practice in the field of prevention or interception of PsA and for clinical management of people with PsO at risk for PsA development. METHODS: A multidisciplinary EULAR task force of 30 members from 13 European countries was established, and the EULAR standardised operating procedures for development for PtC were followed. Two systematic literature reviews were conducted to support the task force in formulating the PtC. Furthermore, the task force proposed nomenclature for the stages before PsA, through a nominal group process to be used in clinical trials. RESULTS: Nomenclature for the stages preceding PsA onset, 5 overarching principles and 10 PtC were formulated. Nomenclature was proposed for three stages towards PsA development, namely people with PsO at higher risk of PsA, subclinical PsA and clinical PsA. The latter stage was defined as PsO and associated synovitis and it could be used as an outcome measure for clinical trials evaluating the transition from PsO to PsA. The overarching principles address the nature of PsA at its onset and underline the importance of collaboration of rheumatologists and dermatologists for strategies for prevention/interception of PsA. The 10 PtC highlight arthralgia and imaging abnormalities as key elements of subclinical PsA that can be used as potential short-term predictors of PsA development and useful items to design clinical trials for PsA interception. Traditional risk factors for PsA development (ie, PsO severity, obesity and nail involvement) may represent more long-term disease predictors and be less robust for short-term trials concerning the transition from PsO to PsA. CONCLUSION: These PtC are helpful to define the clinical and imaging features of people with PsO suspicious to progress to PsA. This information will be helpful for identification of those who could benefit from a therapeutic intervention to attenuate, delay or prevent PsA development.

EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2022 update.

OBJECTIVES: To provide an update of the EULAR rheumatoid arthritis (RA) management recommendations addressing the most recent developments in the field. METHODS: An international task force was formed and solicited three systematic literature research activities on safety and efficacy of disease-modifying antirheumatic drugs (DMARDs) and glucocorticoids (GCs). The new evidence was discussed in light of the last update from 2019. A predefined voting process was applied to each overarching principle and recommendation. Levels of evidence and strengths of recommendation were assigned to and participants finally voted on the level of agreement with each item. RESULTS: The task force agreed on 5 overarching principles and 11 recommendations concerning use of conventional synthetic (cs) DMARDs (methotrexate (MTX), leflunomide, sulfasalazine); GCs; biological (b) DMARDs (tumour necrosis factor inhibitors (adalimumab, certolizumab pegol, etanercept, golimumab, infliximab including biosimilars), abatacept, rituximab, tocilizumab, sarilumab and targeted synthetic (ts) DMARDs, namely the Janus kinase inhibitors tofacitinib, baricitinib, filgotinib, upadacitinib. Guidance on monotherapy, combination therapy, treatment strategies (treat-to-target) and tapering in sustained clinical remission is provided. Safety aspects, including risk of major cardiovascular events (MACEs) and malignancies, costs and sequencing of b/tsDMARDs were all considered. Initially, MTX plus GCs is recommended and on insufficient response to this therapy within 3-6 months, treatment should be based on stratification according to risk factors; With poor prognostic factors (presence of autoantibodies, high disease activity, early erosions or failure of two csDMARDs), any bDMARD should be added to the csDMARD; after careful consideration of risks of MACEs, malignancies and/or thromboembolic events tsDMARDs may also be considered in this phase. If the first bDMARD (or tsDMARD) fails, any other bDMARD (from another or the same class) or tsDMARD (considering risks) is recommended. With sustained remission, DMARDs may be tapered but should not be stopped. Levels of evidence and levels of agreement were high for most recommendations. CONCLUSIONS: These updated EULAR recommendations provide consensus on RA management including safety, effectiveness and cost.

Rheumatoid arthritis presenting with mono- or oligo-arthritis and high VAS remains most fatigued during 5-years follow-up.

OBJECTIVES: The severity of fatigue in rheumatoid arthritis (RA) has hardly improved in recent decades, leaving a large unmet need. Fortunately, not all RA-patients suffer from persistent fatigue, but the subgroup of patients who suffer the most is insufficiently recognizable at diagnosis. As disease activity is partly coupled to fatigue, Disease-Activity-Score (DAS)-components may associate with the course of fatigue. We aimed to identify the RA-patients who remain fatigued by studying DAS-components at diagnosis in relation to the course of fatigue over a 5-year follow-up period in two independent early RA-cohorts. METHODS: 1560 consecutive RA-patients included in the Leiden Early Arthritis Cohort and 415 RA-patients included in the tREACH-Cohort were studied. Swollen joint count, tender joint count, ESR and Patient Global Assessment (Visual Analogue Scale(VAS),0-100 mm) were studied in relation to fatigue(VAS, 0-100mm) during 5-years using linear mixed models. RESULTS: Higher TJC and PGA at diagnosis were associated with a more severe course of fatigue. The SJC, in contrast, showed an inverse association; patients with mono- or oligo-arthritis at diagnosis remained more fatigued. The combination of aforementioned characteristics revealed that patients presenting with a mono- or oligo-arthritis and PGA ≥ 50 remained the most fatigued over time(+20mm vs polyarthritis with PGA < 50), whilst the DAS-course over time was not different. This subgroup comprised 14% of the early RA-population. Data from the tREACH-cohort showed similar findings. CONCLUSION: RA-patients who remain the most fatigued are characterized by mono- or oligo-arthritis and high PGA(VAS ≥ 50) at diagnosis. This understanding may enable early-intervention with non-pharmacological approaches in dedicated patient groups.

Patient-reported swelling in arthralgia patients at risk for rheumatoid arthritis: is it of value?

OBJECTIVE: Patients with Clinically Suspect Arthralgia (CSA) are at risk for developing Rheumatoid Arthritis (RA). These patients often report joint swelling while this is not objectified by physical examination. To explore the value of patient-reported swelling in CSA, we aimed to determine its association with subclinical joint-inflammation on imaging and RA-development. METHODS: In two independent, similarly designed CSA-cohorts from the Netherlands, symptomatic patients at risk for RA were studied. At baseline, patients indicated whether they had experienced swelling in hand joints. Subclinical joint-inflammation was assessed with MRI or ultrasound (US). Patients were followed for inflammatory arthritis development. RESULTS: In total, 534 CSA-patients from two independent cohorts were studied, patient-reported swelling was present in 57% in cohort 1, and in 43% in cohort 2. In both cohorts patient-reported swelling was associated with subclinical joint-inflammation. Using MRI, it associated specifically with tenosynovitis (OR 3.7 (95%CI 2.0-6.9)) and when using US with synovitis (OR 2.3 (95%CI 1.04-5.3)). CSA-patients with self-reported swelling at baseline developed arthritis more often, with hazard ratios of 3.7 (95%CI 2.0-6.9) and 3.4 (95%CI 1.4-8.4) in cohort 1 and 2, respectively. This was independent of clinical predictors (e.g. morning stiffness), autoantibody-positivity and US-detected subclinical joint-inflammation. However, when corrected for MRI-detected subclinical joint-inflammation, self-reported swelling was no longer an independent predictor. CONCLUSION: Patient-reported joint swelling in CSA relates to subclinical joint-inflammation and is an independent risk factor for RA-development, but it is less predictive than the presence of MRI-detected subclinical joint-inflammation.

Machine learning identifies a profile of inadequate responder to methotrexate in rheumatoid arthritis.

OBJECTIVES: Around 30% of patients with RA have an inadequate response to MTX. We aimed to use routine clinical and biological data to build machine learning models predicting EULAR inadequate response to MTX and to identify simple predictive biomarkers. METHODS: Models were trained on RA patients fulfilling the 2010 ACR/EULAR criteria from the ESPOIR and Leiden EAC cohorts to predict the EULAR response at 9 months (± 6 months). Several models were compared on the training set using the AUROC. The best model was evaluated on an external validation cohort (tREACH). The model's predictions were explained using Shapley values to extract a biomarker of inadequate response. RESULTS: We included 493 therapeutic sequences from ESPOIR, 239 from EAC and 138 from tREACH. The model selected DAS28, Lymphocytes, Creatininemia, Leucocytes, AST, ALT, swollen joint count and corticosteroid co-treatment as predictors. The model reached an AUROC of 0.72 [95% CI (0.63, 0.80)] on the external validation set, where 70% of patients were responders to MTX. Patients predicted as inadequate responders had only 38% [95% CI (20%, 58%)] chance to respond and using the algorithm to decide to initiate MTX would decrease inadequate-response rate from 30% to 23% [95% CI: (17%, 29%)]. A biomarker was identified in patients with moderate or high activity (DAS28 > 3.2): patients with a lymphocyte count superior to 2000 cells/mm3 are significantly less likely to respond. CONCLUSION: Our study highlights the usefulness of machine learning in unveiling subgroups of inadequate responders to MTX to guide new therapeutic strategies. Further work is needed to validate this approach.

Clinically suspect arthralgia patients with a low educational attainment have an increased risk of developing inflammatory arthritis.

OBJECTIVES: Cross-sectional studies have shown that rheumatoid arthritis is more prevalent among people with a lower educational attainment. No longitudinal data are present on educational attainment in the at-risk phase of clinically suspect arthralgia (CSA). We therefore analysed the association between educational attainment and progression from CSA to inflammatory arthritis (IA), and performed mediation analysis with subclinical joint inflammation to elucidate pathways of this association. METHODS: A total of 521 consecutive patients presenting with CSA were followed for IA development during median 25 months. Educational attainment was defined as low (lower secondary vocational education), intermediate or high (college/university education). Subclinical inflammation in hand and foot joints was measured at presentation with contrast enhanced 1.5 T-MRI. Cox-regression was used to analyse IA development per educational attainment. A three-step mediation analysis evaluated whether subclinical joint inflammation was intermediary in the path between educational attainment and IA development, before and after age correction. Association between educational attainment and IA development was verified in an independent CSA cohort. RESULTS: Low educational attainment was associated with increased IA development (HR = 2.35, 95% CI = 1.27, 4.33, P = 0.006), independent of BMI and current smoking status (yes/no). Moreover, patients with a low educational attainment had higher levels of subclinical inflammation, which also was associated with IA development. Partial mediation effect of subclinical inflammation was observed in the relationship between education and IA development. Low educational attainment was also associated with increased IA development in the validation cohort (HR = 5.72, 95% CI = 1.36, 24.08, P = 0.017). CONCLUSION: This is the first study providing evidence that lower educational attainment is associated with a higher risk of progressing from arthralgia to IA. This effect was partially mediated by subclinical joint inflammation.

Towards a simplified fluid-sensitive MRI protocol in small joints of the hand in early arthritis patients: reliability between modified Dixon and regular Gadolinium enhanced TSE fat saturated MRI-sequences.

OBJECTIVE: MRI of small joints plays an important role in the early detection and early treatment of rheumatoid arthritis. Despite its sensitivity to demonstrate inflammation, clinical use is hampered by accessibility, long scan time, intravenous contrast, and consequent high costs. To improve the feasibility of MRI implementation in clinical practice, we introduce a modified Dixon sequence, which does not require contrast and reduces total acquisition time to 6 min. Because the reliability in relation to conventional MRI sequences is unknown, we determined this. METHODS: In 29 consecutive early arthritis patients, coronal and axial T2-weighted modified Dixon acquisitions on 3.0 T MRI scanner were acquired from metacarpophalangeal 2-5 to the wrist, followed by the standard contrast-enhanced protocol on 1.5 T extremity MRI. Two readers scored osteitis, synovitis and tenosynovitis (summed as total MRI-inflammation), and erosions (all summed as total Rheumatoid Arthritis MRI Score (RAMRIS)). Intraclass correlation coefficients (ICCs) between readers, and comparing the two sequences, were studied. Spearman correlations were determined. RESULTS: Performance between readers was good/excellent. Comparing modified Dixon and conventional sequences revealed good/excellent reliability: ICC for total MRI-inflammation score was 0.84 (95% CI:0.70-0.92), for erosions 0.90 (95% CI:0.79-0.96), and for the total RAMRIS score 0.88 (95% CI:0.77-0.94). The scores of total MRI-inflammation, total erosions, and total RAMRIS were highly correlated (ρ = 0.80, ρ = 0.81, ρ = 0.82, respectively). CONCLUSION: The modified Dixon protocol is reliable compared to the conventional MRI protocol, suggesting it is accurate to detect MRI inflammation. The good correlation may be the first step towards a patient-friendly, short and affordable MRI protocol, which can facilitate the implementation of MRI for early detection of inflammation in rheumatology practice.

Determining in which pre-arthritis stage HLA-shared epitope alleles and smoking exert their effect on the development of rheumatoid arthritis.

OBJECTIVES: The human leukocyte antigen-shared epitope (HLA-SE) alleles and smoking are the most prominent genetic and environmental risk factors for rheumatoid arthritis (RA). However, at which pre-arthritis stage (asymptomatic/symptomatic) they exert their effect is unknown. We aimed to determine whether HLA-SE and smoking are involved in the onset of autoantibody positivity, symptoms (clinically suspect arthralgia (CSA)) and/or progression to clinical arthritis. METHODS: We performed meta-analyses on results from the literature on associations of HLA-SE and smoking with anti-citrullinated protein antibodies (ACPAs) in the asymptomatic population. Next, we studied associations of HLA-SE and smoking with autoantibody positivity at CSA onset and with progression to clinical inflammatory arthritis (IA) during follow-up. Associations in ACPA-positive patients with CSA were validated in meta-analyses with other arthralgia cohorts. Analyses were repeated for rheumatoid factor (RF), anti-carbamylated protein antibodies (anti-CarP) and anti-acetylated protein antibodies (AAPA). RESULTS: Meta-analyses showed that HLA-SE is not associated with ACPA positivity in the asymptomatic population (OR 1.06 (95% CI:0.69 to 1.64)), whereas smoking was associated (OR 1.37 (95% CI: 1.15 to 1.63)). At CSA onset, both HLA-SE and smoking associated with ACPA positivity (OR 2.08 (95% CI: 1.24 to 3.49), OR 2.41 (95% CI: 1.31 to 4.43)). During follow-up, HLA-SE associated with IA development (HR 1.86 (95% CI: 1.23 to 2.82)), in contrast to smoking. This was confirmed in meta-analyses in ACPA-positive arthralgia (HR 1.52 (95% CI: 1.08 to 2.15)). HLA-SE and smoking were not associated with RF, anti-CarP or AAPA-positivity at CSA onset. Longitudinally, AAPA associated with IA development independent from ACPA and RF (HR 1.79 (95% CI: 1.02 to 3.16)), anti-CarP did not. CONCLUSIONS: HLA-SE and smoking act at different stages: smoking confers risk for ACPA and symptom development, whereas HLA-SE mediates symptom and IA development. These data enhance the understanding of the timing of the key risk factors in the development of RA.

Undifferentiated arthritis: a changing population who did not benefit from enhanced disease-modifying anti-rheumatic drug strategies-results from a 25 year longitudinal inception cohort.

OBJECTIVES: International guidelines stress timely DMARD initiation in early arthritis as well as when classification criteria are not yet fulfilled. Consequently, undifferentiated arthritis (UA) patients may be increasingly treated with DMARDs. Since UA is a diagnosis of exclusion, the introduction of the 2010 classification criteria presumably decreased the UA population, as former UA patients became regarded as RA. Consequently, the contemporary definition of UA has changed into: no clinical diagnosis and not fulfilling the 1987 nor 2010 RA-criteria. Importantly, placebo-controlled trials on DMARD efficacy in contemporary UA are absent. We aimed to study whether enhanced treatment strategies across the last 25 years improved outcomes in contemporary UA, whereby inclusion period was used as instrumental variable for DMARD treatment. METHODS: UA was defined, retrospectively, as clinical arthritis (joint swelling at physical examination) neither fulfilling the 1987 nor 2010 RA-criteria or any other clinical diagnosis. In total, 1132 UA patients consecutively included in the Leiden Early Arthritis Clinic between 1993 and 2019 were divided into five inclusion periods: 1993-1997, 1998-2005, 2006-2010, 2011-2014 and 2015-2019. The frequency of DMARD initiation was compared across the inclusion periods, as were the following outcomes: 28-joint DAS with CRP (DAS28-CRP) and the HAQ Disability Index (HAQ-DI) during follow-up, prevalence of DMARD-free-status within 10 years (DFS; spontaneous remission or sustained remission after DMARD stop) and progression to RA (according 1987/2010 criteria). RESULTS: The contemporary UA population is mainly autoantibody negative, with a median swollen joint count of 2, tender joint count of 3 and HAQ score of 0.6. These characteristics were similar across the inclusion periods. DMARD treatment increased from 17% (1993-1997) to 52% (2015-2019) and methotrexate became more common. The DAS28-CRP during follow-up improved from 2011 onwards (-0.18 to -0.25 DAS units; P < 0.05). Disability scores during follow-up did not significantly improve. DFS prevalence also remained similar: 58%, 57% and 61% for 1993-1997, 1998-2005 and 2006-2010, respectively (P = 0.77). Likewise, the percentages of RA development did not decrease (14%, 21%, 26%, 18% and 27%, respectively). CONCLUSION: Although intensified DMARD treatment slightly improved disease activity scores, physical functioning and long-term outcomes did not improve. This suggests overtreatment in the contemporary UA population and underlines the importance of developing stratification methods suitable for this patient-population.

Morning stiffness precedes the development of rheumatoid arthritis and associates with systemic and subclinical joint inflammation in arthralgia patients.

OBJECTIVES: Morning stiffness (MS) is characteristic of RA and associates with markers of systemic and local inflammation in RA patients. In patients with arthralgia, MS is a cardinal symptom to recognize arthralgia at-risk for RA development [i.e. clinically suspect arthralgia (CSA)]. In CSA, MS is also assumed to reflect inflammation, but this has never been studied. Therefore we aimed to study whether MS in CSA patients is associated with systemic and subclinical joint inflammation. METHODS: A total of 575 patients presenting with CSA underwent laboratory investigations and contrast-enhanced 1.5 T MRI of the hand and forefoot (scored according to the Rheumatoid Arthritis MRI Score method). Associations of MS (duration ≥60 min) with the presence of subclinical joint inflammation (synovitis, tenosynovitis and osteitis) and increased CRP (≥5 mg/l) were determined with logistic regression. Additionally, the effect of MS duration (≥30, ≥60 and ≥120 min) was studied. RESULTS: A total of 195 (34%) CSA patients experienced MS. These patients more often had subclinical synovitis [34% vs 21%; odds ratio (OR) 1.95 (95% CI 1.32, 2.87)], subclinical tenosynovitis [36% vs 26%; OR 1.59 (95% CI 1.10, 2.31)] and increased CRP [31% vs 19%; OR 1.93 (95% CI 1.30, 2.88)] than patients without MS. In multivariable analyses, subclinical synovitis [OR 1.77 (95% CI 1.16, 2.69)] and CRP [OR 1.78 (95% CI 1.17-2.69)] remained independently associated with MS. In CSA patients who later developed RA, and thus in retrospect were 'pre-RA' at the time of CSA, MS was more strongly associated with subclinical synovitis [OR 2.56 (95% CI 1.04, 6.52)] and CRP [OR 3.86 (95% CI 1.45, 10.24)]. Furthermore, associations increased with longer MS durations. CONCLUSION: Inflammation associates with MS in the CSA phase that preceded clinical arthritis. These results increase our understanding of MS when assessing arthralgia in clinical practice.

MRI-detected synovitis of the small joints predicts rheumatoid arthritis development in large joint undifferentiated inflammatory arthritis.

OBJECTIVES: New onset undifferentiated large joint inflammatory arthritis can be diagnostically challenging. It is unknown how often these patients progress to RA, and how they can be identified at first presentation. We assessed clinical and serological features associated with RA development in patients with an undifferentiated mono- or oligo-articular large joint arthritis, and with keen interest in whether an MRI of the small joints of the hand and foot would aid diagnosis. METHODS: Leiden Early Arthritis Clinic includes 4018 patients; this prospective study follows 221 consecutively included patients with new onset undifferentiated large joint arthritis. Baseline clinical data and serology were obtained. Forty-five patients had MRIs (hand and foot). MRIs were scored according to the OMERACT RAMRIS. Univariable and multivariable logistic regression were assessed. Test characteristics, predictive values and net reclassification index (NRI) for RA were determined. RESULTS: Patients mostly presented with knee or ankle mono-arthritis. During the 12 months' follow-up 17% developed RA. Autoantibody positivity (ACPA and/or RF) and MRI-detected synovitis in hands and feet were independently associated with RA development in multivariable analyses [odds ratio 10.29 (P = 0.014) and 7.88 (P = 0.017), respectively]. Positive predictive value of autoantibodies, MRI-detected synovitis and combination of both features was 63%, 55% and 100%, respectively. The addition of MRI-detected synovitis to autoantibody status improved diagnostic accuracy (NRI 18.1%). CONCLUSION: In patients presenting with undifferentiated large joint arthritis, 17% will develop RA. Autoantibody positivity and subclinical synovitis are independent predictors. The data suggest MRI of small joints is beneficial for early identification of RA in large joint arthritis.

Hand and foot MRI in contemporary undifferentiated arthritis: in which patients is MRI valuable to detect rheumatoid arthritis early? A large prospective study.

OBJECTIVES: Identifying patients that will develop RA among those presenting with undifferentiated arthritis (UA) remains a clinical dilemma. Although MRI is helpful according to EULAR recommendations, this has only been determined in UA patients not fulfilling 1987 RA criteria, while some of these patients are currently considered as RA because they fulfil the 2010 criteria. Therefore, we studied the predictive value of MRI for progression to RA in the current UA population, i.e. not fulfilling RA classification criteria (either 1987 or 2010 criteria) and not having an alternate diagnosis. Additionally, the value of MRI was studied in patients with a clinical diagnosis of UA, regardless of the classification criteria. METHODS: Two UA populations were studied: criteria-based UA as described above (n = 405) and expert-opinion-based UA (n = 564), i.e. UA indicated by treating rheumatologists. These patients were retrieved from a large cohort of consecutively included early arthritis patients that underwent contrast-enhanced MRI scans of hand and foot at baseline. MRIs were scored for osteitis, synovitis and tenosynovitis. Patients were followed for RA development during the course of 1 year. Test characteristics of MRI were determined separately for subgroups based on joint involvement and autoantibody status. RESULTS: Among criteria-based UA patients (n = 405), 21% developed RA. MRI-detected synovitis and MRI-detected tenosynovitis were predictive for progression to RA. MRI-detected tenosynovitis was independently associated with RA progression (odds ratio (OR) 2.79; 95% CI 1.40, 5.58), especially within ACPA-negative UA patients (OR 2.91; 95% CI 1.42, 5.96). Prior risks of RA development for UA patients with mono-, oligo- and polyarthritis were 3%, 19% and 46%, respectively. MRI results changed this risk most within the oligoarthritis subgroup: positive predictive value was 27% and negative predictive value 93%. Similar results were found in expert-opinion-based UA (n = 564). CONCLUSION: This large cohort study showed that MRI is most valuable in ACPA-negative UA patients with oligoarthritis; a negative MRI could aid in preventing overtreatment.