Background: We investigated sensitivity to change of three scoring methods of the Health Assessment Questionnaire (HAQ) in relation to change in disease activity in patients with active rheumatoid... Show moreBackground: We investigated sensitivity to change of three scoring methods of the Health Assessment Questionnaire (HAQ) in relation to change in disease activity in patients with active rheumatoid arthritis (RA).Patients and Methods: Adult RA-patients with complete data in the Measurement of Efficacy of Treatment in the Era of Outcome in Rheumatology database with respect to the 20 HAQ questions and disease activity score with 28-joint count using the erythrocyte sedimentation rate (DAS28-ESR) for 2 visits, at least 6-12 months apart, and high disease activity (DAS28-ESR >5.1) at visit 1. Changes in HAQ scored by the (1) conventional method (HAQ-8), (2) HAQ-Tomlin method (HAQ-T), and (3) HAQ-20-item method (HAQ-20) were analyzed in relation to the European League Against Rheumatism (EULAR) RA response criteria, dichotomized to good/moderate and no response.Results: In 421 patients, mean standard deviation (SD) DAS28-ESR declined significantly (6.1 [0.8]-4.8 [1.6], P < 0.0001), over a mean period (SD) of 8.7 (1.9) months. Median HAQ scores improved by all three scoring methods, HAQ-8 (1.6-1.4); HAQ-T (1.2-0.7); and HAQ-20 (1.2-0.9) with similar effect sizes of 0.97, 0.96, and 0.95, respectively. The proportion who achieved a HAQ minimally clinically important improvement (MCII) of >= 0.22 was significantly higher in 47% of patients with EULAR good/moderate score compared to the no response patients (64% vs. 11%, P < 0.0001). Good/moderate EULAR response, higher baseline DAS28, and higher baseline HAQ (7.11, 1.55, and 1.06, respectively) were independent predictors of achieving a HAQ-MCII.Conclusion: Three HAQ scoring methods performed similarly in sensitivity to change with no advantage of alternative scoring methods compared to the conventional HAQ-8 method. A good/moderate EULAR response, despite long disease duration, was associated with a significant likelihood of achieving a HAQ-MCII. Show less
Background: Patients with immune-mediated inflammatory diseases (IMIDs) on immunosuppressants (ISPs) may have impaired long-term humoral immune responses and increased disease activity after SARS... Show moreBackground: Patients with immune-mediated inflammatory diseases (IMIDs) on immunosuppressants (ISPs) may have impaired long-term humoral immune responses and increased disease activity after SARS-CoV-2 infection. We aimed to investigate long-term humoral immune responses against SARS-CoV-2 and increased disease activity after a primary SARS-CoV-2 infection in unvaccinated IMID patients on ISPs. Methods: IMID patients on active treatment with ISPs and controls (i.e. IMID patients not on ISP and healthy controls) with a confirmed SARS-CoV-2 infection before first vaccination were included from an ongoing prospective cohort study (T2B! study). Clinical data on infections and increased disease activity were registered using electronic surveys and health records. A serum sample was collected before first vaccination to measure SARS-CoV-2 anti-receptor-binding domain (RBD) antibodies. Results: In total, 193 IMID patients on ISP and 113 controls were included. Serum samples from 185 participants were available, with a median time of 173 days between infection and sample collection. The rate of seropositive IMID patients on ISPs was 78% compared to 100% in controls (p < 0.001). Seropositivity rates were lowest in patients on anti-CD20 (40.0%) and anti-tumor necrosis factor (TNF) agents (60.5%), as compared to other ISPs (p < 0.001 and p < 0.001, respectively). Increased disease activity after infection was reported by 68 of 260 patients (26.2%; 95% CI 21.2-31.8%), leading to ISP intensification in 6 out of these 68 patients (8.8%). Conclusion: IMID patients using ISPs showed reduced long-term humoral immune responses after primary SARS-CoV-2 infection, which was mainly attributed to treatment with anti-CD20 and anti-TNF agents. Increased disease activity after SARS-CoV-2 infection was reported commonly, but was mostly mild. Show less
BackgroundPatients with immune-mediated inflammatory diseases (IMIDs) on immunosuppressants (ISPs) may have impaired long-term humoral immune responses and increased disease activity after SARS-CoV... Show moreBackgroundPatients with immune-mediated inflammatory diseases (IMIDs) on immunosuppressants (ISPs) may have impaired long-term humoral immune responses and increased disease activity after SARS-CoV-2 infection. We aimed to investigate long-term humoral immune responses against SARS-CoV-2 and increased disease activity after a primary SARS-CoV-2 infection in unvaccinated IMID patients on ISPs.MethodsIMID patients on active treatment with ISPs and controls (i.e. IMID patients not on ISP and healthy controls) with a confirmed SARS-CoV-2 infection before first vaccination were included from an ongoing prospective cohort study (T2B! study). Clinical data on infections and increased disease activity were registered using electronic surveys and health records. A serum sample was collected before first vaccination to measure SARS-CoV-2 anti-receptor-binding domain (RBD) antibodies.ResultsIn total, 193 IMID patients on ISP and 113 controls were included. Serum samples from 185 participants were available, with a median time of 173 days between infection and sample collection. The rate of seropositive IMID patients on ISPs was 78% compared to 100% in controls (p < 0.001). Seropositivity rates were lowest in patients on anti-CD20 (40.0%) and anti-tumor necrosis factor (TNF) agents (60.5%), as compared to other ISPs (p < 0.001 and p < 0.001, respectively). Increased disease activity after infection was reported by 68 of 260 patients (26.2%; 95% CI 21.2–31.8%), leading to ISP intensification in 6 out of these 68 patients (8.8%).ConclusionIMID patients using ISPs showed reduced long-term humoral immune responses after primary SARS-CoV-2 infection, which was mainly attributed to treatment with anti-CD20 and anti-TNF agents. Increased disease activity after SARS-CoV-2 infection was reported commonly, but was mostly mild. Show less
For patients with immune-mediated inflammatory diseases (IMIDs), concerns exist about increased disease ac-tivity after vaccination. We aimed to assess changes in disease activity after SARS-CoV-2... Show moreFor patients with immune-mediated inflammatory diseases (IMIDs), concerns exist about increased disease ac-tivity after vaccination. We aimed to assess changes in disease activity after SARS-CoV-2 vaccination in patients with IMIDs, and determine risk factors for increased disease activity. In this substudy of a prospective obser-vational cohort study (Target-to-B!), we included patients with IMIDs who received a SARS-CoV-2 vaccine. Patients reported changes in disease activity on a five-point Likert scale every 60 days for up to twelve months after first vaccination. In case of self-reported increased activity, hospital records were screened whether the treating physician reported increased activity, and for potential intensification of immunosuppressive (ISP) treatment. Mixed models were used to study determinants for self-reported increased disease activity. In total, 2111 patients were included for analysis after primary immunization (mean age 49.7 years [SD 13.7], 1329/ 2111 (63.0%) female), from which 1266 patients for analysis after first additional vaccination. Increased disease activity at 60 days after start of primary immunization was reported by 223/2111 (10.6%). In 96/223 (43.0%) the increase was confirmed by the treating physician and in 36/223 (16.1%) ISP treatment was intensified. Increased disease activity at seven to 60 days after additional vaccination, was reported by 139/1266 (11.0%). Vaccinations were not temporally associated with self-reported increased disease activity. Conversely, increased disease activity before first vaccination, neuromuscular disease, and multiple sclerosis were associated. Alto-gether, self-reported increased disease activity after vaccination against SARS-CoV-2 was recorded in a minority of patients and was generally mild. Moreover, multivariate analyses suggest that disease related factors, but not vaccinations are the major determinants for self-reported increased disease activity. Show less
For patients with immune-mediated inflammatory diseases (IMIDs), concerns exist about increased disease activity after vaccination. We aimed to assess changes in disease activity after SARS-CoV-2... Show moreFor patients with immune-mediated inflammatory diseases (IMIDs), concerns exist about increased disease activity after vaccination. We aimed to assess changes in disease activity after SARS-CoV-2 vaccination in patients with IMIDs, and determine risk factors for increased disease activity. In this substudy of a prospective observational cohort study (Target-to-B!), we included patients with IMIDs who received a SARS-CoV-2 vaccine. Patients reported changes in disease activity on a five-point Likert scale every 60 days for up to twelve months after first vaccination. In case of self-reported increased activity, hospital records were screened whether the treating physician reported increased activity, and for potential intensification of immunosuppressive (ISP) treatment. Mixed models were used to study determinants for self-reported increased disease activity. In total, 2111 patients were included for analysis after primary immunization (mean age 49.7 years [SD 13.7], 1329/2111 (63.0%) female), from which 1266 patients for analysis after first additional vaccination. Increased disease activity at 60 days after start of primary immunization was reported by 223/2111 (10.6%). In 96/223 (43.0%) the increase was confirmed by the treating physician and in 36/223 (16.1%) ISP treatment was intensified. Increased disease activity at seven to 60 days after additional vaccination, was reported by 139/1266 (11.0%). Vaccinations were not temporally associated with self-reported increased disease activity. Conversely, increased disease activity before first vaccination, neuromuscular disease, and multiple sclerosis were associated. Altogether, self-reported increased disease activity after vaccination against SARS-CoV-2 was recorded in a minority of patients and was generally mild. Moreover, multivariate analyses suggest that disease related factors, but not vaccinations are the major determinants for self-reported increased disease activity. Show less
Kharagjitsing, H.H.S.; Hendriksz, T.R.; Fouraux, M.A.; Gelder, T. van; Bommel, E.F.H. van 2022
Background: Idiopathic retroperitoneal fibrosis (iRPF) is a rare chronic fibro-inflammatory disorder of unknown etiology. Activated T-helper cells, which shed soluble interleukin-2 receptor (sIL-2R... Show moreBackground: Idiopathic retroperitoneal fibrosis (iRPF) is a rare chronic fibro-inflammatory disorder of unknown etiology. Activated T-helper cells, which shed soluble interleukin-2 receptor (sIL-2R) into the circulation, may play a pathogenetic role. Hence, measuring sIL-2R may be of value in monitoring disease activity and treatment response in iRPF patients. Methods: We performed a prospective inception cohort study of 82 patients with untreated (re)active iRPF stratified by elevated (> 623 U/mL) or normal sIL-2R level at baseline and compared disease characteristics among these groups. Baseline and changes in sIL-2R levels following treatment with tamoxifen (TMX) or prednisone (PDN) were analyzed and related to treatment response. Results: Median sIL-2R level was 668 U/mL (IQR 502.8-827.5); 48 patients (59%) had elevated baseline sIL-2R levels. Patients with elevated sIL-2R presented with higher CRP (P = 0.049) and serum creatinine (sCr) levels (P < 0.001) and more often had hydroureteronephrosis (P = 0.01). There was an age and sex adjusted linear association between baseline sIL-2R and both CRP (P = 0.02) and sCr (P < 0.001). Baseline and serial levels of sIL-2R were predictive and concordant, respectively, with clinical response in patients treated with PDN. ROC curve analyses of sIL-2R on a continuous scale and PDN treatment success showed an AUC of 0.84. A serum sIL-2R cut-off value for PDN treatment success of <= 703 U/mL was found with a sensitivity of 100% and specificity of 72%. Conclusion: Serial measurement of sIL-2R may be of value in monitoring disease activity and PDN treatment response in iRPF patients. Show less
Capelusnik, D.; Ramiro, S.; Schneeberger, E.E.; Citera, G. 2021
Objetive: The aim of this study was to investigate whether peripheral arthritis together with disease activity independently contribute to functional impairment over time in patients with axSpA and... Show moreObjetive: The aim of this study was to investigate whether peripheral arthritis together with disease activity independently contribute to functional impairment over time in patients with axSpA and to evaluate if there are contextual factors modifying this relationship.Material and methods: Patients with axial spondyloarthritis from the ESPAXIA cohort were followed-up annually over a mean of 3.7 years. Physical function was assessed by the self-reported questionnaire BASFI, disease activity by ASDAS and peripheral arthritis was also recorded. Generalized estimating equations (GEE) were used to investigate longitudinal association between peripheral arthritis, ASDAS and BASFI as the outcome. Autoregressive models (adjusted for BASFI 1 year earlier) were run to allow for a truly longitudinal interpretation. Interactions between each of ASDAS and peripheral arthritis with contextual factors (age, gender, educational level, smoking, job type) were tested.Results: 185 patients (77 % male, mean (SD) age 42 (13) years old and mean disease duration (SD) of 9.4 (9.6) years) were included. ASDAS and peripheral arthritis independently contributed to explaning BASFI over time. Contextual factors did not modify either of the relationships. A true longitudinal relation was proven with the autoregressive GEE model, showing that, adjusted for age, gender, spinal mobility and use of NSAIDs, an increase of one ASDAS unit led to a BASFI 0.48 units higher (ss 0.48 [95%CI 0.39, 0.57]), and the presence of peripheral arthritis, to a BASFI 0.44 units higher (ss 0.44 [95%CI 0.08, 0.8]). Conclusion: Peripheral arthritis and higher disease activity independently lead to more functional impairment in axSpA over time. Contextual factors do not modify these relationships.(c) 2021 Elsevier Inc. All rights reserved. Show less
Objectives Rheumatoid arthritis (RA) patients show an earlier circadian rhythm (i.e. serum melatonin peaks earlier during the night, indicating an earlier timing of the internal circadian pacemaker... Show moreObjectives Rheumatoid arthritis (RA) patients show an earlier circadian rhythm (i.e. serum melatonin peaks earlier during the night, indicating an earlier timing of the internal circadian pacemaker). In the current study, we examined whether the chronotype, which is influenced by the circadian rhythm, is also earlier. In addition, we explored whether chronotype is related to disease activity and patient-reported outcomes.Methods The chronotype (Munich Chronotype Questionnaire) of patients with RA (n = 121; mean age 60 years, 73% female) was compared with that of subjects from the general population (norm group; n = 1695) with a one-sample t test. In addition, we investigated chronotype in relation to disease activity (Disease Activity Score; DAS), reported morning stiffness, fatigue (Checklist Individual Strength), and health-related quality of life (RAND-36).Results The chronotype of patients with RA was, on average, 23 min (95% CI, 15 to 31 min) earlier than that of the norm group (t(115) = - 5.901, p < 0.001, d = 0.55). Chronotype was not related to disease activity or patient-reported outcomes (p > 0.05).Conclusion As expected, chronotype was earlier in RA patients. However, in this correlational study, chronotype was not related to disease activity or patient-reported outcomes. An experimental study is needed to examine whether delaying the circadian rhythm has a positive influence on these outcomes. This insight could improve our understanding of the pathophysiology of RA and contribute to exploring new treatment possibilities.Key Points This is the first study examining chronotype in patients with rheumatoid arthritis, and how chronotype relates to disease activity and patient-reported outcomes.We found an earlier chronotype in patients with rheumatoid arthritis than in subjects from the general population.In this correlational study, chronotype was not related to disease activity or patient-reported outcomes. An experimental study is needed to examine whether delaying the circadian rhythm positively influences these outcomes. Show less
Background The multi-biomarker disease activity (MBDA) test measures 12 serum protein biomarkers to quantify disease activity in RA patients. A newer version of the MBDA score, adjusted for age,... Show moreBackground The multi-biomarker disease activity (MBDA) test measures 12 serum protein biomarkers to quantify disease activity in RA patients. A newer version of the MBDA score, adjusted for age, sex, and adiposity, has been validated in two cohorts (OPERA and BRASS) for predicting risk for radiographic progression. We now extend these findings with additional cohorts to further validate the adjusted MBDA score as a predictor of radiographic progression risk and compare its performance with that of other risk factors.MethodsFour cohorts were analyzed: the BRASS and Leiden registries and the OPERA and SWEFOT studies (total N =953). Treatments included conventional DMARDs and anti-TNFs. Associations of radiographic progression (Delta TSS) per year with the adjusted MBDA score, seropositivity, and clinical measures were evaluated using linear and logistic regression. The adjusted MBDA score was (1) validated in Leiden and SWEFOT, (2) compared with other measures in all four cohorts, and (3) used to generate curves for predicting risk of radiographic progression.ResultsUnivariable and bivariable analyses validated the adjusted MBDA score and found it to be the strongest, independent predicator of radiographic progression (Delta TSS >5) compared with seropositivity (rheumatoid factor and/or anti-CCP), baseline TSS, DAS28-CRP, CRP SJC, or CDAI. Neither DAS28-CRP, CDAI, SJC, nor CRP added significant information to the adjusted MBDA score as a predictor, and the frequency of radiographic progression agreed with the adjusted MBDA score when it was discordant with these measures. The rate of progression (Delta TSS >5) increased from <2% in the low (1-29) adjusted MBDA category to 16% in the high (45-100) category. A modeled risk curve indicated that risk increased continuously, exceeding 40% for the highest adjusted MBDA scores.ConclusionThe adjusted MBDA score was validated as an RA disease activity measure that is prognostic for radiographic progression. The adjusted MBDA score was a stronger predictor of radiographic progression than conventional risk factors, including seropositivity, and its prognostic ability was not significantly improved by the addition of DAS28-CRP, CRP, SJC, or CDAI. Show less
Objectives To study whether there is an association between body mass index (BMI) category and survival of various tumour necrosis factor inhibitors (TNFi) in rheumatoid arthritis (RA) patients in... Show moreObjectives To study whether there is an association between body mass index (BMI) category and survival of various tumour necrosis factor inhibitors (TNFi) in rheumatoid arthritis (RA) patients in a real-life longitudinal international registry.Methods Data from 5230 patients with RA starting treatment with any TNFi were selected from the METEOR registry. Patients were divided into six BMI categories: 3.7% underweight, BMI<18.5 kg/m(2); 46% normal weight, BMI 18.5-25 kg/m(2); 32% pre-obesity, BMI 25-30 kg/m(2); 13% obesity class I, BMI 30-35 kg/m(2); 3.4% obesity class II, BMI 35-40 kg/m(2); and 1.6% obesity class III, BMI >40 kg/m(2). Time on treatment in the different BMI categories was compared for all TNFi combined and for the infliximab, adalimumab and etanercept separately, using Kaplan-Meier curves and Cox regression analyses. Cox regression analyses were adjusted for potential confounders, with follow-up censored at 5000 days.Results Patients in obesity class II (HR 1.28, 95% CI 1.06 to 1.54) and III (HR 1.67, 95% CI 1.29 to 2.18) and underweight patients (HR 1.30, 95% CI 1.07 to 1.58) showed statistically significantly shorter TNFi survival than normal weight patients. The effect in underweight patients was strongest for infliximab (HR 1.82, 95% CI 1.20 to 2.76), the effect in overweight patients was strongest for infliximab (category II (HR 1.49, 95% CI 0.98 to 2.26); category III (HR 1.46, 95% CI 0.79 to 2.71)) and etanercept (category II (HR 1.27 95% CI 0.98 to 1.65); category III (HR 1.79, 95% CI 1.25 to 2.55)). No significant effect modification from reported pain was found.Conclusion Both underweight and overweight patients discontinued TNFi treatment earlier than normal weight patients, without evidence of reported pain as the main determinant. It remains uncertain what determines TNFi survival in individual patients. Show less
Moel, E.C. de; Rech, J.; Mahler, M.; Roth, J.; Vogl, T.; Schouffoer, A.; ... ; Woude, D. van der 2019
Objective: To investigate whether calprotectin (S100A8/A9 or MRP8/14), an inflammatory complex released by monocytes, could indicate residual subclinical inflammation in rheumatoid arthritis (RA)... Show moreObjective: To investigate whether calprotectin (S100A8/A9 or MRP8/14), an inflammatory complex released by monocytes, could indicate residual subclinical inflammation in rheumatoid arthritis (RA) patients who are in stable remission on disease-modifying anti-rheumatic drugs (DMARDs) and serve as a marker for disease flare after DMARD tapering.Methods: We used data from two trials. Patients from the IMPROVED study had early (< 2 years) RA, and when they achieved disease activity score remission (DAS44 < 1.6), they stopped methotrexate to attempt drug-free remission. Patients from the RETRO study had established RA in stable remission (DAS28 < 2.6) and either tapered by 50% or stopped (biological or conventional) DMARDs. Circulating calprotectin at the tapering time point was determined by ELISA, and its predictive value for flare (loss of remission) within 12 months of DMARD tapering/stopping was determined.Results: In both IMPROVED (n = 104) and RETRO (n = 57), patients that flared within 12 months had higher calprotectin at the moment of DMARD tapering/stopping. Twofold higher calprotectin at the moment of DMARD tapering/stopping was associated with an increased risk (odds ratio) of flare of 1.07 (95% CI 0.98-1.18, p = 0.14) in the IMPROVED and 3.62 (95% CI 1.76-7.46, p < 0.001) in the RETRO. Correcting for clinical predictors of flare (DAS at study inclusion, anti-CCP2 positivity, gender) did not change these estimates. The area under the receiver operating curve of calprotectin levels for predicting flare within 12 months was 0.63 (95% CIs 0.51-0.76) in the IMPROVED study and 0.80 (95% CIs 0.69 to 0.92) in the RETRO study.Conclusion: Circulating calprotectin levels in RA patients in remission on DMARDs are higher in patients that will flare upon DMARD tapering/stopping. Since the differences between the cohorts precluded definitive conclusions, more research is needed to determine whether calprotectin has prognostic value in predicting flare after attempting drug tapering in RA. Show less
BackgroundPrednisone (PDN) in juvenile dermatomyositis (JDM), alone or in association with other immunosuppressive drugs, namely methotrexate (MTX) and cyclosporine (CSA), represents the first-line... Show moreBackgroundPrednisone (PDN) in juvenile dermatomyositis (JDM), alone or in association with other immunosuppressive drugs, namely methotrexate (MTX) and cyclosporine (CSA), represents the first-line treatment option for new onset JDM patients. No clear evidence based guidelines are actually available to standardize the tapering and discontinuation of glucocorticoids (GC) in JDM. Aim of our study was to provide an evidence-based proposal for GC tapering/discontinuation in new onset juvenile dermatomyositis (JDM), and to identify predictors of clinical remission and GC discontinuation.MethodsNew onset JDM children were randomized to receive either PDN alone or in combination with methotrexate (MTX) or cyclosporine (CSA). In order to derive steroid tapering indications, PRINTO/ACR/EULAR JDM core set measures (CSM) and their median absolute and relative percent changes over time were compared in 3 groups. Group 1 included those in clinical remission who discontinued PDN, with no major therapeutic changes (MTC) (reference group) and was compared with those who did not achieve clinical remission, without or with MTC (Group 2 and 3, respectively). A logistic regression model identified predictors of clinical remission with PDN discontinuation.ResultsBased on the median change in the CSM of 30/139 children in Group 1, after 3 pulses of methyl-prednisolone, GC could be tapered from 2 to 1mg/kg/day in the first two months from onset if any of the CSM decreased by 50-94%, and from 1 to 0.2mg/kg/day in the following 4months if any CSM further decreased by 8-68%, followed by discontinuation in the ensuing 18months. The achievement of PRINTO JDM 50-70-90 response after 2months of treatment (ORs range 4.5-6.9), an age at onset >9years (OR 4.6) and the combination therapy PDN+MTX (OR 3.6) increase the probability of achieving clinical remission (p<0.05).ConclusionsThis is the first evidence-based proposal for glucocorticoid tapering/discontinuation based on the change in JDM CSM of disease activity. Show less
In this thesis we aimed to investigate ways to optimize treatment strategies and the choice of treatment for individual patients, to be implemented in a worldwide context. Although major advances... Show moreIn this thesis we aimed to investigate ways to optimize treatment strategies and the choice of treatment for individual patients, to be implemented in a worldwide context. Although major advances have been made in the treatment of RA, it is still uncertain which treatment is the best choice for each individual patient. This can result in both overtreatment and undertreatment, increasing the burden of RA for patients as well as for society. In clinical trials and daily practice there appears to be a development towards earlier treatment, with higher dosages of medication and more stringent treatment targets. In part 1 of this thesis, some of these developments were investigated and challenged. In countries across the world, patients do not benefit similarly from recent advances in the treatment of RA. In part 2 of this thesis, we aimed to identify contributing factors to inequalities in access to treatment and care and clinical outcomes across countries, as a first step towards improvement. Show less
Ferreira, R.J.O.; Welsing, P.M.J.; Gossec, L.; Jacobs, J.W.G.; Machado, P.M.; Ndosi, M.; ... ; Silva, J.A.P. da 2018
This thesis is two-fold focused on rheumatoid arthritis and axial spondyloarthritis. It covers outstanding aspects of research methodology in the assessment of inflammation and damage in patients... Show moreThis thesis is two-fold focused on rheumatoid arthritis and axial spondyloarthritis. It covers outstanding aspects of research methodology in the assessment of inflammation and damage in patients with these diseases. The studies pertaining to the first part of the thesis focus on rheumatoid arthritis and may help to better understand the relationship between disease activity, radiographic damage and disability. More specifically, they evaluate which of the available tools (individual instruments or composite indices) is associated with radiographic damage and which of the different types of structural lesions detectable on radiographs is associated with disability. Additionally, these studies address methodological issues related to the optimal assessment of radiographic progression in clinical trials. The studies described in the second part of the thesis evaluate the benefit of supplementary tests reflecting inflammation, especially to help classifying (diagnosing) patients and to monitor disease activity. Among others, the studies described in this thesis provide data that allow a better usage of these tests in clinical practice. Overall, this thesis provide guidelines on how to assess properly rheumatoid arthritis and axial spondyloarthritis in clinical trials and in clinical practice. This precise way of assessment will lead to a better understanding and a better management of these diseases. Show less