The 2023 ACR/EULAR Classification Criteria for Calcium Pyrophosphate Deposition Disease.

OBJECTIVE: Calcium pyrophosphate deposition (CPPD) disease is prevalent and has diverse presentations, but there are no validated classification criteria for this symptomatic arthritis. The American College of Rheumatology (ACR) and EULAR have developed the first-ever validated classification criteria for symptomatic CPPD disease. METHODS: Supported by the ACR and EULAR, a multinational group of investigators followed established methodology to develop these disease classification criteria. The group generated lists of candidate items and refined their definitions, collected de-identified patient profiles, evaluated strengths of associations between candidate items and CPPD disease, developed a classification criteria framework, and used multi-criterion decision analysis to define criteria weights and a classification threshold score. The criteria were validated in an independent cohort. RESULTS: Among patients with joint pain, swelling, or tenderness (entry criterion) whose symptoms are not fully explained by an alternative disease (exclusion criterion), the presence of crowned dens syndrome or calcium pyrophosphate crystals in synovial fluid are sufficient to classify a patient as having CPPD disease. In the absence of these findings, a score >56 points using weighted criteria, comprising clinical features, associated metabolic disorders, and results of laboratory and imaging investigations, can be used to classify as CPPD disease. These criteria had a sensitivity of 92.2% and specificity of 87.9% in the derivation cohort (190 CPPD cases, 148 mimickers), whereas sensitivity was 99.2% and specificity was 92.5% in the validation cohort (251 CPPD cases, 162 mimickers). CONCLUSION: The 2023 ACR/EULAR CPPD disease classification criteria have excellent performance characteristics and will facilitate research in this field.

The 2023 ACR/EULAR classification criteria for calcium pyrophosphate deposition disease.

OBJECTIVE: Calcium pyrophosphate deposition (CPPD) disease is prevalent and has diverse presentations, but there are no validated classification criteria for this symptomatic arthritis. The American College of Rheumatology (ACR) and EULAR have developed the first-ever validated classification criteria for symptomatic CPPD disease. METHODS: Supported by the ACR and EULAR, a multinational group of investigators followed established methodology to develop these disease classification criteria. The group generated lists of candidate items and refined their definitions, collected de-identified patient profiles, evaluated strengths of associations between candidate items and CPPD disease, developed a classification criteria framework, and used multi-criterion decision analysis to define criteria weights and a classification threshold score. The criteria were validated in an independent cohort. RESULTS: Among patients with joint pain, swelling, or tenderness (entry criterion) whose symptoms are not fully explained by an alternative disease (exclusion criterion), the presence of crowned dens syndrome or calcium pyrophosphate crystals in synovial fluid are sufficient to classify a patient as having CPPD disease. In the absence of these findings, a score>56 points using weighted criteria, comprising clinical features, associated metabolic disorders, and results of laboratory and imaging investigations, can be used to classify as CPPD disease. These criteria had a sensitivity of 92.2% and specificity of 87.9% in the derivation cohort (190 CPPD cases, 148 mimickers), whereas sensitivity was 99.2% and specificity was 92.5% in the validation cohort (251 CPPD cases, 162 mimickers). CONCLUSION: The 2023 ACR/EULAR CPPD disease classification criteria have excellent performance characteristics and will facilitate research in this field.

Erosive Hand OsteoArthritis (EHOA): analysis of consecutive patients presenting with EHOA in a hospital-based rheumatology practice and its implications for an upcoming interventional study.

INTRODUCTION: Erosive Hand OsteoArthritis (EHOA) is a common rheumatological problem. We aim to determine characteristics of EHOA patients: comorbidities, radiographic erosivity and pain experienced after being diagnosed, in order to find which of these are potentially relevant in upcoming interventional trials. METHOD: Retrospective analysis of EHOA patients within the electronic database in one centre, with a telephone interview on pain as experienced even exceeding 12 months after being diagnosed. RESULTS: Eighty-four non-academic EHOA patients were found: 89% females (median age 69 years), 11% males (similar age distribution). Kellgren-Lawrence (KL) erosivity scores in both sexes were comparable; DIPs scored higher than PIP's. Comorbid conditions were crystal-induced arthritis, rheumatoid arthritis (RA) and psoriatic arthritis (PsA) in 8%, 5% and 1%, respectively; seropositivity for rheumatoid factor and anti-citrullinated protein antibodies in 8% and 1% respectively. Pain worst experienced often exceeded a visual analogue score of 5.0, but was unrelated to the total KL score. Some pain reduction was reached with non-steroidals (perorally/transcutaneously) as deduced from continued use in 1 in 3. CONCLUSIONS: In many EHOA patients, there is an unmet need regarding the treatment of pain, which per se was not directly correlated with erosivity score. Future studies may be designed considering the aforementioned characteristics, acting on the inflammatory process resulting in PIP/DIP erosions, with the exclusion of RA and PsA in order to get a clean study on EHOA. Several studies with monoclonal antibodies have been performed but demonstrated ineffectivity on the outcome of pain. Hope glooms with the arrival of innovative small molecules that may reach EHOA target cells. Key Points • Erosive handOA is a common problem in non-academic rheumatology; it is often associated with significant pain in both sexes exceeding a VASpain of 5.0 even years after being diagnosed; 1 in 3 found some relief in non-steroidals perorally/transcutaneously. • Future studies will have to focus on (episodic) inflammatory hand OA resulting in proven erosivity (EHOA) located in PIP plus DIP joints and may have to exclude comorbid active crystal-induced arthritis as well as rheumatoid/psoriatic arthritis and possibly even RF/ACPA seropositivity in order to get a clean study on EHOA. • As several big monoclonals have failed in EHOA, we may have to search for promising new drugs within the group of small molecules. These will have to show a significant pain-reducing effect and preferably also a disease-modifying osteoarthritis drug (DMOAD) effect.

Emerging and New Treatment Options for Knee Osteoarthritis.

Osteoarthritis (OA) is the most prevalent type of arthritis worldwide, resulting in pain and often chronic disability and a significant burden on healthcare systems globally. Non-steroidal anti-inflammatory drugs (NSAIDs), analgesics, intra-articular corticosteroid injections are of little value in the long term, and opioids may have ominous consequences. Radiotherapy of knee OA has no added value. Physical therapy, exercises, weight loss, and lifestyle modifications may give pain relief, improve physical functioning and quality of life. However, none of them has articular cartilage regenerating potential. Due to a better understanding of osteoarthritis, innovative new treatment options have been developed. In this narrative review, we focus on emerging OA knee treatments, relieving symptoms, and regenerating damaged articular cartilage that includes intra-articular human serum albumin, conventional disease-modifying anti-rheumatic drugs (DMARDs), metformin, lipid-lowering agents (statin), nerve growth factors antagonists, bone morphogenetic protein, fibroblast growth factors, Platelet-Rich Plasma (PRP), Mesenchymal Stem Cells (MSC), exosomes, interleukin-1 blockers, gene-based therapy, and bisphosphonate.

Sex Differences in the Clinical Profile Among Patients With Gout: Cross-sectional Analyses of an Observational Study.

OBJECTIVE: Research findings in gout result predominantly from studies about men and might not be generalizable to women. To improve insight into sex differences in gout, our study compared clinical characteristics and comorbidities of female and male patients with gout, and explored the influence of menopause on these differences. METHODS: Data from patients referred to 2 rheumatology clinics and diagnosed with gout were used. Clinical characteristics and comorbidities of each sex were compared univariately. Sex difference in comorbidities were further explored in multivariate logistic regression analyses adjusting for age, BMI, smoking, and alcohol consumption in both the total group and in those with gout onset ≥ 55 years (as a surrogate for menopausal state). RESULTS: There were 954 patients, including 793 (83%) men, included. Women were on average older (65 vs 62 yrs), were more often obese (54% vs 36%), had a higher serum uric acid (sUA) level (0.53 vs 0.49 mmol/L), used diuretics more often (60% vs 30%), and consumed alcohol less frequently (47% vs 72%). Additionally, women more frequently had reduced renal function (64% vs 31%), hypertension (78% vs 56%), heart failure (23% vs 12%), and type 2 diabetes (39% vs 17%; all P < 0.05). In those with gout onset ≥ 55 years, differences in comorbidities were less pronounced and disappeared after adjusting for lifestyle. CONCLUSION: Our study confirmed sex differences in clinical characteristics and comorbidities among newly diagnosed patients with gout, and revealed that sex differences in comorbidities among those with gout onset beyond the age of female menopause were strongly attenuated and fully explained by lifestyle.

Rare genetic variants in interleukin-37 link this anti-inflammatory cytokine to the pathogenesis and treatment of gout.

OBJECTIVE: Gout is characterised by severe interleukin (IL)-1-mediated joint inflammation induced by monosodium urate crystals. Since IL-37 is a pivotal anti-inflammatory cytokine suppressing the activity of IL-1, we conducted genetic and functional studies aimed at elucidating the role of IL-37 in the pathogenesis and treatment of gout. METHODS: Variant identification was performed by DNA sequencing of all coding bases of IL37 using molecular inversion probe-based resequencing (discovery cohort: gout n=675, controls n=520) and TaqMan genotyping (validation cohort: gout n=2202, controls n=2295). Predictive modelling of the effects of rare variants on protein structure was followed by in vitro experiments evaluating the impact on protein function. Treatment with recombinant IL-37 was evaluated in vitro and in vivo in a mouse model of gout. RESULTS: We identified four rare variants in IL37 in six of the discovery gout patients; p.(A144P), p.(G174Dfs*16), p.(C181*) and p.(N182S), whereas none emerged in healthy controls (Fisher's exact p-value=0.043). All variants clustered in the functional domain of IL-37 in exon 5 (p-value=5.71×10-5). Predictive modelling and functional studies confirmed loss of anti-inflammatory functions and we substantiated the therapeutic potential of recombinant IL-37 in the treatment of gouty inflammation. Furthermore, the carrier status of p.(N182S)(rs752113534) was associated with increased risk (OR=1.81, p-value=0.031) of developing gout in hyperuricaemic individuals of Polynesian ancestry. CONCLUSION: Here, we provide genetic as well as mechanistic evidence for the role of IL-37 in the pathogenesis of gout, and highlight the therapeutic potential of recombinant IL-37 for the treatment of gouty arthritis.

Pleiotropic effect of the ABCG2 gene in gout: involvement in serum urate levels and progression from hyperuricemia to gout.

BACKGROUND: The ABCG2 Q141K (rs2231142) and rs10011796 variants associate with hyperuricaemia (HU). The effect size of ABCG2 rs2231142 on urate is ~ 60% that of SLC2A9, yet the effect size on gout is greater. We tested the hypothesis that ABCG2 plays a role in the progression from HU to gout by testing for association of ABCG2 rs2231142 and rs10011796 with gout using HU controls. METHODS: We analysed 1699 European gout cases and 14,350 normouricemic (NU) and HU controls, and 912 New Zealand (NZ) Polynesian (divided into Eastern and Western Polynesian) gout cases and 696 controls. Association testing was performed using logistic and linear regression with multivariate adjusting for confounding variables. RESULTS: In Europeans and Polynesians, the ABCG2 141K (T) allele was associated with gout using HU controls (OR = 1.85, P = 3.8E- 21 and ORmeta = 1.85, P = 1.3E- 03, respectively). There was evidence for an effect of 141K in determining HU in European (OR = 1.56, P = 1.7E- 18) but not in Polynesian (ORmeta = 1.49, P = 0.057). For SLC2A9 rs11942223, the T allele associated with gout in the presence of HU in European (OR = 1.37, P = 4.7E- 06), however significantly weaker than ABCG2 rs2231142 141K (PHet = 0.0023). In Western Polynesian and European, there was epistatic interaction between ABCG2 rs2231142 and rs10011796. Combining the presence of the 141K allele with the rs10011796 CC-genotype increased gout risk, in the presence of HU, 21.5-fold in Western Polynesian (P = 0.009) and 2.6-fold in European (P = 9.9E- 06). The 141K allele of ABCG2 associated with increased gout flare frequency in Polynesian (Pmeta = 2.5E- 03). CONCLUSION: These data are consistent with a role for ABCG2 141K in gout in the presence of established HU.

Systematic genetic analysis of early-onset gout: ABCG2 is the only associated locus.

OBJECTIVE: The aim of this study was to examine whether serum urate-associated genetic variants are associated with early-onset gout. METHODS: Participants with gout in the Genetics of Gout in Aotearoa study with available genotyping were included (n = 1648). Early-onset gout was defined as the first presentation of gout <40 years of age. Single nucleotide polymorphisms (SNPs) for the 10 loci most strongly associated with serum urate were genotyped. Allelic association of the SNPs with early-onset gout was tested using logistic regression in an unadjusted model and in a model adjusted for sex, body mass index, tophus presence, flare frequency, serum creatinine and highest serum urate. The analysis was also done in two replication cohorts: Eurogout (n = 704) and Ardea (n = 755), and data were meta-analysed. RESULTS: In the Genetics of Gout in Aotearoa study, there were 638 (42.4%) participants with early-onset gout. The ABCG2 rs2231142 gout risk T-allele was present more frequently in participants with early-onset gout compared with the later-onset group. For the other SNPs tested, no differences in risk allele number were observed. In the allelic association analysis, the ABCG2 rs2231142 T-allele was associated with early-onset gout in unadjusted and adjusted models. Analysis of the replication cohorts confirmed the association of early-onset gout with the ABCG2 rs2231142 T-allele, but not with other serum urate-associated SNPs. In the meta-analysis, the odds ratio (95% CI) for early-onset gout for the ABCG2 rs2231142 T-allele was 1.60 (1.41, 1.83). CONCLUSION: In contrast to other serum urate-raising variants, the ABCG2 rs2231142 T-allele is strongly associated with early-onset gout.

Predictors of biologic-free disease control in patients with rheumatoid arthritis after stopping tumor necrosis factor inhibitor treatment.

BACKGROUND: The aim of this study was to identify predictors of prolonged disease control after discontinuation of tumor necrosis factor inhibitor (TNFi) treatment in patients with rheumatoid arthritis (RA). METHODS: Post-hoc analysis of 439 RA patients (67.3% rheumatoid factor positive) with longstanding RA in remission or with stable low disease activity, randomized to stopping TNFi treatment in the multicenter POET trial. Prolonged acceptable disease control was defined as not restarting TNFi treatment within 12 months after stopping. Baseline demographic and disease-related variables were included in univariate and multivariate logistic regression analysis for identifying predictors of relapse. RESULTS: One year after baseline, 220 patients (50.1%) had not restarted TNFi treatment. Use of an anti-TNF monoclonal antibody (versus a receptor antagonist, OR = 2.41; 95% CI: 1.58-3.67), ≤10 yrs. disease duration (OR = 2.15; 95% CI: 1.42-3.26) and low or moderate multi-biomarker disease activity (MBDA) scores (OR = 2.00; 95% CI: 1.10-3.64) at baseline were independently predictive of successful TNFi discontinuation (area under the receiver operating characteristic curve = 0.66; 95% CI: 0.61-0.71). Results were similar when using no physician-reported flare as the criterion. TNFi-free survival was significantly different for patient groups based on the number of predictors present, ranging from 21.4% of patients with no predictor present to 66.7% of patients with all three predictors present. CONCLUSION: Patients using an anti-TNF monoclonal antibody, with shorter disease duration and low or moderate baseline MBDA score are most likely to achieve prolonged disease control after TNFi discontinuation. TRIAL REGISTRATION: Netherlands Trial Register NTR3112, 21 October 2011.

Crystal-proven gout patients have an increased mortality due to cardiovascular diseases, cancer, and infectious diseases especially when having tophi and/or high serum uric acid levels: a prospective cohort study.

OBJECTIVE: To investigate the cause-specific mortality and the possible involved clinical characteristics with increased mortality in a cohort of 700 patients with crystal-proven gout. The cause-specific mortality of gout was compared to the mortality of the general population. METHODS: Patients with arthritis referred for diagnosis were consecutively included in the Gout Arnhem-Liemers Cohort (GOAL). Joint fluid analysis was performed in all patients and only crystal-proven gout patients were included in this study. At inclusion clinical characteristics and laboratory values were collected. At follow-up patients who died were identified. Standardized mortality ratios (SMRs) were calculated for all-causes, cardiovascular diseases, cancer, and infectious diseases using indirect standardization methods for mortality outcomes and compared with the general population. The clinical characteristics of the patients who died were compared with those of the survivors and were analyzed by a logistic regression analysis to identify any associations with mortality. RESULTS: The study population at inclusion contained 573 (81.9%) men and 127 (18.1%) females with an average age of 62.0 (SD 13.4). During 3500 person-years from inclusion visit till 31 May 2016, in 700 gout patients, 66 deaths (27 cardiovascular deaths, 15 cancer-related deaths, 8 infectious deaths, 16 various other causes) occurred in this cohort. The all-cause standardized mortality ratio in gout patients was 2.21 (95% CI 1.68-2.74). In this cohort, gout patients had a higher SMR for death attributed to cardiovascular diseases (6.75; 95% CI 4.64-8.86), infectious diseases (4.66; 95% CI 1.51-7.82) and cancer (3.58; 95% CI 1.77-5.39). Corrected for confounders high serum uric acid levels (SUA; > 0,56 mmol/L), tophaceous gout, a history of peripheral vascular disease, myocardial infarction, and heart failure at the inclusion visit were associated with increased mortality during follow-up. CONCLUSION: Compared to the general population, gout patients have an increased association with all-cause disease mortality, especially attributed to cardiovascular diseases, cancer, and infectious diseases. This association is strongest in hyperuricemic (uric acid levels > 0,56 mmol/l) and tophaceous patients and in those with a history of peripheral vascular disease, myocardial infarction, and heart failure. Preventive measures like treatment of high SUA levels and treatment of cardiovascular risk factors need to be considered and evaluated.

Gout lessons from 2018: CARES, a direct comparison of febuxostat vs allopurinol, and CANTOS, IL1 blocker for cardiovascular risk minimisation.

In the Cardiovascular Safety of Febuxostat and Allopurinol in Patients with Gout and Cardiovascular Morbidities (CARES) trial conducted by White et al. (March 29 issue from NEJM), all-cause mortality and cardiovascular mortality are found to be higher among patients randomly assigned to febuxostat compared to allopurinol, but significant flaws are a clear lack of treat to target strategy with more powered treatment in the febuxostat arm, dysbalance with cardiovascular risk factors selectively in again the febuxostat arm, and discontinuation of the trial regimen in over 50% of patients with discontinuation of follow-up in about 45%. With these flaws, conclusions such as febuxostat-associated higher mortality are potentially if not probably incorrect, and thus febuxostat to be used not as first-line therapy may well be an invalid consequence? The paper here describes potential lessons to be taken.

Multi-biomarker disease activity score as a predictor of disease relapse in patients with rheumatoid arthritis stopping TNF inhibitor treatment.

OBJECTIVE: Successfully stopping or reducing treatment for patients with rheumatoid arthritis (RA) in low disease activity (LDA) may improve cost-effectiveness of care. We evaluated the multi-biomarker disease activity (MBDA) score as a predictor of disease relapse after discontinuation of TNF inhibitor (TNFi) treatment. METHODS: 439 RA patients who were randomized to stop TNFi treatment in the POET study were analyzed post-hoc. Three indicators of disease relapse were assessed over 12 months: 1) restarting TNFi treatment, 2) escalation of any DMARD therapy and 3) physician-reported flare. MBDA score was assessed at baseline. Associations between MBDA score and disease relapse were examined using univariate analysis and multivariate logistic regression. RESULTS: At baseline, 50.1%, 35.3% and 14.6% of patients had low (<30), moderate (30-44) or high (>44) MBDA scores. Within 12 months, 49.9% of patients had restarted TNFi medication, 59.0% had escalation of any DMARD and 57.2% had ≥1 physician-reported flare. MBDA score was associated with each indicator of relapse. At least one indicator of relapse was observed in 59.5%, 68.4% and 81.3% of patients with low, moderate or high MBDA scores, respectively (P = 0.004). Adjusted for baseline DAS28-ESR, disease duration, BMI and erosions, high MBDA scores were associated with increased risk for restarting TNFi treatment (OR = 1.85, 95% CI 1.00-3.40), DMARD escalation (OR = 1.99, 95% CI 1.01-3.94) and physician-reported flare (OR = 2.00, 95% 1.06-3.77). CONCLUSION: For RA patients with stable LDA who stopped TNFi, a high baseline MBDA score was independently predictive of disease relapse within 12 months. The MBDA score may be useful for identifying patients at risk of relapse after TNFi discontinuation.

Vasodilator function worsens after cessation of tumour necrosis factor inhibitor therapy in patients with rheumatoid arthritis only if a flare occurs.

Vasodilator function is reported to be reduced in rheumatoid arthritis (RA), and is considered an early sign of vascular dysfunction, which is normalised by TNF inhibitors (TNFi). To optimise cost-effectiveness, tapering or interruption of TNFi therapy in established RA patients is advocated. We explored whether cessation of TNFi results in impaired vasodilator function and whether this relates to the development of a Disease Activity Score (DAS28)-based flare. Forty-one patients were assessed for eligibility as RA with at least 12 months of low disease activity (based on 28 joint counts); 35 enrolled into the randomised study: 8 were randomised to continue, 27 to stopping TNFi. Forearm vasodilation to acetylcholine (ACh) and sodium nitroprusside (SNP) was assessed before cessation of TNFi therapy (visit 1) and 6 months after (dis)continuation of TNFi or at flare (based on DAS28) whichever came first (visit 2). None of the patients who continued their TNFi therapy flared. Eight out of 22 patients who stopped TNFi therapy flared. The vasodilator response to ACh and SNP was reduced significantly in patients who experienced a flare of RA: In patients who did not experience a flare, the vasodilator response to ACh or SNP was not significantly affected. Vasodilator function is reduced after cessation of TNFi, but only when RA reactivates, indicating that early vasodilator dysfunction is a consequence rather than a cause of systemic inflammation in RA and not specifically related to inhibition of TNFα signalling. Without close monitoring, microvascular damage can occur after TNFi interruption with potential devastating implications for cardiovascular health. TRIAL REGISTRATION: NCT02130076.

Impact of Stopping Tumor Necrosis Factor Inhibitors on Rheumatoid Arthritis Patients' Burden of Disease.

OBJECTIVE: To determine the impact of stopping tumor necrosis factor inhibitor (TNFi) treatment on patient-reported outcomes (PROs) of physical and mental health status, health utility, pain, disability, and fatigue in patients with established rheumatoid arthritis (RA). METHODS: In the pragmatic, 12-month POET trial, 817 RA patients with ≥6 months of remission or stable low disease activity were randomized 2:1 to stopping or continuing TNFi. In case of flare, TNFi was restarted at the discretion of the rheumatologist. PROs were assessed every 3 months. RESULTS: TNFi was restarted within 12 months in 252 of 531 patients (47.5%) in the stop group. At 3 months, mean PRO scores were significantly worse in the stop group, and a larger proportion of patients experienced a minimum clinically important difference (MCID) on all PROs. Effect sizes (ES) were strongest for health utility (ES -0.24) and pain (ES -0.30). Mean scores improved again after this point, but disability scores remained significantly different at 12 months. After 12 months, the relative risk of experiencing an MCID ranged from 1.16 for mental health status to 1.58 for fatigue. Mean PRO scores for patients restarting TNFi within 6 months were no longer significantly different from those that did not restart TNFi at 12 months. CONCLUSION: Stopping TNFi had a significant negative short-term impact on a broad range of PROs. Long-term negative consequences appeared to be limited, and outcomes in patients needing to restart TNFi within the first 6 months tended to be restored at 12 months.

Limited value for ultrasonography in predicting flare in rheumatoid arthritis patients with low disease activity stopping TNF inhibitors.

Objective: Ultrasonography (US) can be used for treatment decisions in RA patients. This study investigated the added value of US to clinical variables in predicting flare in RA patients with longstanding low disease activity when stopping TNF inhibitors (TNFi). Methods: Cox models with and without using US added to clinical variables were developed in the Potential Optimization of Expediency of TNFi-UltraSonography study. RA patients (n = 259), using >1 year TNFi and csDMARD with DAS28 < 3.2 for 6 months prior to inclusion, were followed for 52 weeks after stopping TNFi. The added value of US was assessed in two ways: first, by the extent to which individual predictions for flare at 52 weeks with and without US differed; and second, by comparing how US information improved the prediction to classify patients at 52 weeks in the low risk (<33% flare), intermediate risk (33-50%) and high risk (50-100%) groups. Results: Although US was predictive of flare at group level (multivariate hazard ratio = 1.7; 95% CI: 1.1, 2.5), individual predictions for flare at 52 weeks with and without US differed little (median difference 3.7%; interquartile range: -7.8 to 6.5%). With US, 15.9% of patients were designated low risk; without US, 14.6%. In fact, 12.0% of patients were US-classified as low risk with/without knowing US. Conclusion: In RA patients with longstanding low disease activity, at time of stopping TNFi, US is a predictor for flare at group level, but at the patient level, US has limited added value when common clinical parameters are used already, though the predictive value of clinical predictors is modest as well.

Measuring Disease Exacerbation and Flares in Rheumatoid Arthritis: Comparison of Commonly Used Disease Activity Indices and Individual Measures.

OBJECTIVE: To evaluate and compare the utility of commonly used outcome measures for assessing disease exacerbation or flare in patients with rheumatoid arthritis (RA). METHODS: Data from the Dutch Potential Optimalisation of (Expediency) and Effectiveness of Tumor necrosis factor-α blockers (POET) study, in which 462 patients discontinued their tumor necrosis factor-α inhibitor, were used. The ability of different measures to discriminate between those with and without physician-reported flare or medication escalation at the 3-month visit (T2) was evaluated by calculating effect size (ES) statistics. Responsiveness to increased disease activity was compared between measures by standardizing change scores (SCS) from baseline to the 3-month visit. Finally, the incremental validity of individual outcome measures beyond the Simplified Disease Activity Score was evaluated using logistic regression analysis. RESULTS: The SCS were greater for disease activity indices than for any of the individual measures. The 28-joint Disease Activity Score, Clinical Disease Activity Index, and Simplified Disease Activity Index performed similarly. Pain and physician's (PGA) and patient's global assessment (PtGA) of disease activity were the most responsive individual measures. Similar results were obtained for discriminative ability, with greatest ES for disease activity indices followed by pain, PGA, and PtGA. Pain was the only measure to demonstrate incremental validity beyond SDAI in predicting 3-month flare status. CONCLUSION: These results support the use of composite disease activity indices, patient-reported pain and disease activity, and physician-reported disease activity for measuring disease exacerbation or identifying flares of RA. Physical function, acute-phase response, and the auxiliary measures fatigue, participation, and emotional well-being performed poorly.

Effectiveness of Tumor Necrosis Factor Inhibitors in Combination with Various csDMARD in the Treatment of Rheumatoid Arthritis: Data from the DREAM Registry.

OBJECTIVE: To analyze and compare the effectiveness and drug survival in patients with rheumatoid arthritis, as measured by 28-joint Disease Activity Score (DAS28) and Health Assessment Questionnaire-Disability Index (HAQ-DI), of tumor necrosis factor inhibitor (TNFi) monotherapy, TNFi + leflunomide (LEF), TNFi + sulfasalazine (SSZ), TNFi + other conventional synthetic disease-modifying antirheumatic drugs (csDMARD), and TNFi + methotrexate (MTX) therapy, in daily practice. METHODS: Data were collected from the DREAM registry. Patients beginning their first TNFi treatment were included in the study: TNFi monotherapy (n = 320), TNFi + SSZ (n = 103), TNFi + LEF (n = 80), TNFi + other csDMARD (n = 99), TNFi + MTX alone (n = 919), TNFi + MTX + other csDMARD (n = 412). Treatment effectiveness was analyzed using DAS28 and HAQ-DI with linear mixed models and the TNFi drug survival was analyzed using Kaplan-Meier curves and Cox regression. All analyses have been corrected for confounders. RESULTS: The patients who received TNFi + MTX had significantly better DAS28 and HAQ-DI values over time (both p < 0.001) and longer TNFi drug survival than TNFi monotherapy (p < 0.001). TNFi + SSZ and TNFi + other csDMARD had significantly better DAS28 values over time (p = 0.001) and longer drug survival (p = 0.001) versus TNFi monotherapy. TNFi + LEF was not significantly better compared to monotherapy. Adding other csDMARD to the TNFi + MTX combination provided no added value. CONCLUSION: Preferably, TNFi should be prescribed together with MTX. If this is not possible, we advise the use of other csDMARD.

Stopping Tumor Necrosis Factor Inhibitor Treatment in Patients With Established Rheumatoid Arthritis in Remission or With Stable Low Disease Activity: A Pragmatic Multicenter, Open-Label Randomized Controlled Trial.

OBJECTIVE: Tumor necrosis factor inhibitor (TNFi) biologic agents are an effective treatment for rheumatoid arthritis (RA). It is unclear whether patients whose disease is in remission or who have stable low disease activity need to continue use of TNFi or can stop this treatment. This study was undertaken to assess whether patients with established RA who are in remission or have stable low disease activity can effectively and safely stop their TNFi therapy. METHODS: The study was designed as a pragmatic multicenter, open-label randomized controlled trial. Inclusion criteria were a diagnosis of RA according to the American College of Rheumatology 1987 classification criteria, as well as use of a TNFi for at least 1 year along with a stable dose of disease-modifying antirheumatic drugs and a Disease Activity Score in 28 joints (DAS28) of <3.2 over the 6 months preceding trial inclusion. Patients were randomized in a 2:1 ratio to either stop or continue treatment with their current TNFi. Flare was defined as a DAS28 of ≥3.2 during the 12-month follow-up period and an increase in score of ≥0.6 compared to the baseline DAS28. RESULTS: In total, 531 patients were allocated to the stop group and 286 to the TNFi continuation group. At 12 months, more patients had experienced a flare in the stop group (272 [51.2%] of 531) than in the continuation group (52 [18.2%] of 286; P < 0.001). The hazard ratio for occurrence of a flare after stopping TNFi was 3.50 (95% confidence interval [95% CI] 2.60-4.72). The mean DAS28 in the stop group was significantly higher during the follow-up period compared to that in the continuation group (P < 0.001). Of the 195 patients who restarted TNFi treatment after experiencing a flare and within 26 weeks after stopping, 165 (84.6%) had regained a DAS28 of <3.2 by 6 months later, and the median time to a regained DAS28 of <3.2 was 12 weeks (95% Cl 10.7-13.3). There were more hospitalizations in the stop group than in the continuation group (6.4% versus 2.4%). CONCLUSION: Stopping TNFi treatment results in substantially more flares than does continuation of TNFi in patients with established RA in remission or with stable low disease activity.

Suppression of monosodium urate crystal-induced cytokine production by butyrate is mediated by the inhibition of class I histone deacetylases.

OBJECTIVES: Acute gouty arthritis is caused by endogenously formed monosodium urate (MSU) crystals, which are potent activators of the NLRP3 inflammasome. However, to induce the release of active interleukin (IL)-1ß, an additional stimulus is needed. Saturated long-chain free fatty acids (FFAs) can provide such a signal and stimulate transcription of pro-IL-1ß. In contrast, the short-chain fatty acid butyrate possesses anti-inflammatory effects. One of the mechanisms involved is inhibition of histone deacetylases (HDACs). Here, we explored the effects of butyrate on MSU+FFA-induced cytokine production and its inhibition of specific HDACs. METHODS: Freshly isolated peripheral blood mononuclear cells (PBMCs) from healthy donors were stimulated with MSU and palmitic acid (C16.0) in the presence or absence of butyrate or a synthetic HDAC inhibitor. Cytokine responses were measured with ELISA and quantitative PCR. HDAC activity was measured with fluorimetric assays. RESULTS: Butyrate decreased C16.0+MSU-induced production of IL-1ß, IL-6, IL-8 and IL-1ß mRNA in PBMCs from healthy donors. Similar results were obtained in PBMCs isolated from patients with gout. Butyrate specifically inhibited class I HDACs. The HDAC inhibitor, panobinostat and the potent HDAC inhibitor, ITF-B, also decreased ex vivo C16.0+MSU-induced IL-1ß production. CONCLUSIONS: In agreement with the reported low inhibitory potency of butyrate, a high concentration was needed for cytokine suppression, whereas synthetic HDAC inhibitors showed potent anti-inflammatory effects at nanomolar concentrations. These novel HDAC inhibitors could be effective in the treatment of acute gout. Moreover, the use of specific HDAC inhibitors could even improve the efficacy and reduce any potential adverse effects.