Different Therapeutic Response to Anti-TNF Drugs in Patients with Axial Spondyloarthritis Depending on Their Clinical Profile: An Unsupervised Cluster Analysis

Background: The objectives were as follows: (a) to identify, among patients with axial spondyloarthritis (axSpA), "clusters" of patients based on the presence of peripheral and extra-musculoskeletal manifestations (EMMs) and (b) to compare the effectiveness of the first anti-TNF drugs across the different clusters after 6 months of follow-up. Methods: An observational and retrospective study of 90 axSpA patients naïve to bDMARDs was conducted. An unsupervised cluster analysis using the "k-means" technique was performed using variables of peripheral and EMMs. Baseline clinical and sociodemographic characteristics were evaluated, and the response to anti-TNF treatment (considering responders as those with an improvement ≥1.1 for the Ankylosing Spondylitis Disease Activity Score (ASDAS) or ≥2.0 for the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)) was compared across the clusters after 6 months of follow-up. Results: Two clusters were identified: cluster 1 (n = 14), with a higher prevalence of peripheral manifestations, inflammatory bowel disease (IBD), and HLA-B27-positive status, and a lower prevalence of uveitis in comparison with cluster 2 (n = 76). Patients from cluster 1 experienced a more pronounced absolute improvement in ASDAS and BASDAI indices after 6 months. The percentage of responders after 6 months of follow-up was superior in cluster 1 compared to cluster 2 (85.7% vs. 48.7%, p = 0.011). Conclusion: This study suggests the existence of two clinical profiles in axSpA patients according to the peripheral and EMMs, with higher rates of anti-TNF effectiveness after 6 months in those with a greater presence of peripheral features.

Impact of multimorbidity on the first ts/bDMARD effectiveness and retention rate after two years of follow-up in patients with rheumatoid arthritis from the BIOBADASER registry

BACKGROUND

Patients with Rheumatoid Arthritis (RA) have a higher prevalence of comorbidities compared to the general population. However, the implications of multimorbidity on therapeutic response and treatment retention remain unexplored.

OBJECTIVES

(a) To evaluate the impact of multimorbidity on the effectiveness of the first targeted synthetic or biologic disease-modifying antirheumatic drug (ts/bDMARD), in patients with RA after 2-year follow-up; (b) to investigate the influence of multimorbidity on treatment retention rate.

METHODS

Patients with RA from the BIOBADASER registry exposed to a first ts/bDMARDs were included. Patients were categorized based on multimorbidity status at baseline, defined as a Charlson Comorbidity index (CCI) score ≥ 3. A linear regression model, adjusted for sex and age, was employed to compare the absolute DAS28 score over time after ts/bDMARD initiation between the two groups. The Log-Rank test and Kaplan-Meier curve were used to compare the retention rates of the first ts/bDMARD between the groups.

RESULTS

A total of 1128 patients initiating ts/bDMARD were included, with 107 (9.3%) exhibiting multimorbidity. The linear regression model showed significantly higher DAS28 (beta coefficient 0.33, 95%CI:0.07-0.58) over a two-year period in patients with multimorbidity, even after adjusting for age and sex. Finally, no differences in the ts/bDMARD retention rate were found between groups (median 6.94-6.96 years in CCI < 3 vs. 5.68-5.62 in CCI ≥ 3; p = 0.610).

CONCLUSIONS

Multimorbidity in patients with RA was associated with greater DAS28 scores within the first two years after ts/bDMARD initiation, in comparison with patients without multimorbidity. A slightly shorter retention rate was found in patients with multimorbidity, although the difference was non-significant.

Exploring candidate biomarkers for rheumatoid arthritis through cardiovascular and cardiometabolic serum proteome profiling

Introduction

RA patients are at higher risk of cardiovascular disease, influenced by therapies. Studying their cardiovascular and cardiometabolic proteome can unveil biomarkers and insights into related biological pathways.

Methods

This study included two cohorts of RA patients: newly diagnosed individuals (n=25) and those with established RA (disease duration >25 years, n=25). Both cohorts were age and sex-matched with a control group (n=25). Additionally, a longitudinal investigation was conducted on a cohort of 25 RA patients treated with methotrexate and another cohort of 25 RA patients treated with tofacitinib for 6 months. Clinical and analytical variables were recorded, and serum profiling of 184 proteins was performed using the Olink technology platform.

Results

RA patients exhibited elevated levels of 75 proteins that might be associated with cardiovascular disease. In addition, 24 proteins were increased in RA patients with established disease. Twenty proteins were commonly altered in both cohorts of RA patients. Among these, elevated levels of CTSL1, SORT1, SAA4, TNFRSF10A, ST6GAL1 and CCL18 discriminated RA patients and HDs with high specificity and sensitivity. Methotrexate treatment significantly reduced the levels of 13 proteins, while tofacitinib therapy modulated the expression of 10 proteins. These reductions were associated with a decrease in DAS28. Baseline levels of SAA4 and high levels of BNP were associated to the non-response to methotrexate. Changes in IL6 levels were specifically linked to the response to methotrexate. Regarding tofacitinib, differences in baseline levels of LOX1 and CNDP1 were noted between non-responder and responder RA patients. In addition, response to tofacitinib correlated with changes in SAA4 and TIMD4 levels.

Conclusion

In summary, this study pinpoints molecular changes linked to cardiovascular disease in RA and proposes candidate protein biomarkers for distinguishing RA patients from healthy individuals. It also highlights how methotrexate and tofacitinib impact these proteins, with distinct alterations corresponding to each drug's response, identifying potential candidates, as SAA4, for the response to these therapies.

Identification of the first signs or symptoms in different spondyloarthritis subtypes and their association with HLA-B27: data from REGISPONSER and RESPONDIA registries

OBJECTIVE

To describe and analyse the initial symptoms attributable to patients with spondyloarthritis (SpA) and their association with HLA-B27 status.

METHODS

This was an observational, cross-sectional and multicentre study with patients who fulfilled the European Spondyloarthropathy Study Group criteria for SpA from the Registry of Spondyloarthritis of Spanish Rheumatology (REGISPONSER) and Ibero-American Registry of Spondyloarthropathies (RESPONDIA) united registries. Differences in the first sign(s) or symptom(s) were compared across diagnoses and between HLA-B27 status. The diagnostic delay between patients who start the disease with musculoskeletal manifestations (MMs) and extra-MMs (EMMs) was compared.

RESULTS

A total of 4067 patients were included (2208 from REGISPONSER and 1859 from RESPONDIA) (ankylosing spondylitis (AS): 68.3%, psoriatic arthritis (PsA): 19.9%, undifferentiated SpA: 11.8%). Overall, 3624 (89.1%) patients initiated the disease with MMs and 443 (10.9%) with EMMs. Low back pain (61.7%) and lower-limb arthritis (38.5%) were the most frequent initial symptoms. In AS patients, the absence of HLA-B27 seems to be related to an increase in the probability of starting the disease with cervical pain and peripheral manifestations. In PsA, the onset of arthritis and psoriasis was more prevalent in HLA-B27-negative patients, while initiation with axial manifestations was more predominant in HLA-B27-positive patients. The diagnostic delay was longer in patients with initial MMs than in those with EMMs (7.2 (34.8) vs 4.5 (7.6) years, respectively).

CONCLUSION

In this SpA population, MMs were the most prevalent initial symptoms, with differences across diagnoses and depending on the presence of the HLA-B27 antigen.

Differences between early vs. late-onset of psoriatic arthritis: Data from the RESPONDIA and REGISPONSER registries

OBJECTIVES

The objective was to evaluate the association between the age at onset of psoriatic arthritis (PsA) symptoms with the characteristics and burden of the disease.

METHODS

This was an observational and cross-sectional study that included a subgroup of 231 patients with PsA with < 10 years of disease duration from the REGISPONSER and RESPONDIA registries. Patients were divided into two groups according to the age of PsA symptom onset (early onset: ≤ 40-years-old and late onset: ≥ 60-years-old). The characteristics and burden of the disease were compared between the two groups, and multivariate logistic regression was performed to determine the factors independently associated with late-onset PsA.

RESULTS

Patients from the early-onset group showed a significantly lower prevalence of males [94 (62.3%) vs. 38 (86.4%)] and a higher prevalence of enthesitis [44 (24.6%) vs. 5 (9.8%)] and sacroiliitis [30 (16.8%) vs. 4 (7.7%)]. Additionally, the early-onset group showed lower scores on the BASFI [2.2 (2.2) vs. 3.3 (2.5)] and minor structural damage (BASRI) in both the spine [1.6 (2) vs. 2.9 (3)] and whole axial skeleton (total BASRI) [1.9 (2.4) vs. 3.4 (3.4)]. In contrast, no statistically significant differences were found between the groups in disease activity evaluated by the BASDAI and ASDAS. Logistic regression analysis showed that late-onset PsA was independently associated with being male (OR 4.4, 95% CI: 1.3, 16.3), greater structural damage (total BASRI) (OR 3.3, 95% CI: 1.3, 8.1), a higher frequency of arthritis in the upper limbs (OR 2.8, 95% CI: 1, 7.7), and greater loss of function (BASFI) (OR 1.3, 95% CI: 1, 1.6).

CONCLUSIONS

Patients with late-onset PsA showed different clinical characteristics and greater disease severity than those with early-onset PsA.

Achilles enthesitis on physical examination leads to worse outcomes after 2 years of follow up in patients with ankylosing spondylitis from REGISPONSER-AS registry

BACKGROUND

Enthesitis represents one of the most important peripheral musculoskeletal manifestations in patients with axial spondyloarthritis (axSpA). However, studies specifically evaluating Achilles tendon enthesitis and its impact over time are scarce. The objectives of this study were to evaluate the impact of Achilles' tendon enthesitis found at baseline during physical examination on the outcome measures after 2 years of follow-up in patients with ankylosing spondylitis (AS).

METHODS

This was an observational and prospective study conducted during 2 years of follow-up in the REGISPONSER-AS registry. Linear regression models adjusted for age, body mass index (BMI), and anti-TNF intake were conducted to evaluate the association between the presence of Achilles enthesitis at baseline and the patient-reported outcome (PRO) scores at baseline. The impact of this feature on PROs over 2 years of follow-up was evaluated using mixed models for repeated measures adjusted for age, BMI, and anti-TNF intake.

RESULTS

Among the 749 patients included, 46 patients (6.1%) showed Achilles' tendon enthesitis during physical examination at the baseline study visit. Patients with Achilles enthesitis had an increase in the global VAS score, BASDAI, mBASDAI, ASDAS-CRP, and BASFI scores in comparison with patients without this feature. In addition, the mean global VAS, BASDAI, and ASDAS-CRP scores were significantly higher among patients with Achilles enthesitis over the 2 years of follow-up after adjusting for age, BMI, and current anti-TNF intake. The percentage of patients achieving ASDAS low disease activity (ASDAS < 2.1) after 2 years of follow-up was 15.9% and 31.5% for patients with and without Achilles enthesitis, respectively (p = 0.030).

CONCLUSIONS

In patients with AS, the presence of Achilles' tendon enthesitis was associated with worse scores on the outcome measures after 2 years of follow-up, leading to a lower probability of achieving low disease activity.

Impact of the number of comorbidities on the outcome measures and on the retention rate of the first anti-TNF in patients with Ankylosing Spondylitis. Two-year follow-up in REGISPONSER-AS

OBJECTIVES

To evaluate the impact of the number of comorbidities on the outcome measures after two years of follow-up in patients with Ankylosing Spondylitis (AS) and to determine whether the number of comorbidities influences the retention rate of the first anti-TNF.

METHODS

This was an observational and prospective study conducted during 2 years of follow-up in the REGISPONSER-AS registry. The patients were divided into three groups according to the number of comorbidities at baseline (0, 1 or ≥2). Linear regression models adjusted for disease duration, age, sex and smoking were constructed to evaluate the association between the number of comorbidities and the Patient Reported Outcomes (PRO) scores. The impact of the number of comorbidities on PROs over two years of follow-up was evaluated using mixed models for repeated measures adjusted for disease duration, age, sex and smoking. Finally, the retention rate of the first anti-TNF antibody across the three groups was evaluated using a log-rank test.

RESULTS

Patients with two or more comorbidities showed higher scores at baseline and during the two years of follow-up for the Global VAS, BASDAI, ASDAS, and BASFI and worse scores for the physical component of the SF12. A higher probability of discontinuation of the first anti-TNF was found in patients with 2 or more comorbidities compared with the patients in the other groups (38.2% vs. 26.6% vs. 25.4% for ≥2 comorbidities, 0 and 1 comorbidity, respectively), although these differences were not significant (log-rank test: p-value = 0.180).

CONCLUSION

In patients with AS, the presence of 2 or more comorbidities was associated with worse scores on the outcome measures test after two years of follow-up and a greater tendency of discontinuation for the first anti-TNF.

Paravertebral Muscle Mechanical Properties in Patients with Axial Spondyloarthritis or Low Back Pain: A Case-Control Study

Different musculoskeletal disorders are a source of pain in the spinal region; most of them can be divided into mechanical, such as low back pain (LBP), or inflammatory origins, as is the case of axial spondyloarthritis (axSpA). Nevertheless, insufficient information is available about the muscle negative consequences of these conditions. Thus, the objective of this study was to identify whether mechanical muscle properties (MMPs) of cervical and lumbar muscles are different between patients with axSpA, subacute LBP (sLBP), and healthy controls. Furthermore, we aimed identify whether MMPs were related to sociodemographic and clinical variables in various study groups. The MMPs, sociodemographic, and clinical variables were obtained in 43 patients with axSpA, 43 subjects with sLBP, and 43 healthy controls. One-way ANOVAs and ROC curves were applied to identify whether the MMPs could differentiate between the study groups. Intra-group Pearson r coefficients to test the associations between MMPs and the rest of the variables were calculated. The results showed that axSpA subjects have a higher tone and stiffness and a lower relaxation and creep than sLBP and healthy ones (p < 0.05). All lumbar and cervical MMPs, except for decrement, could correctly classify axSpA and healthy subjects and axSpA and sLBP patients (in both cases, Area Under the Curve > 0.8). However, no MMP could differentiate between sLBP and healthy subjects. Each group had a different pattern of bivariate correlations between MMPs and sociodemographic and clinical data, with a worse state and progression of the axSpA group associated with a higher tone and stiffness in both spinal regions. This study supports that MMPs are different and show different patterns of correlations depending on the type of spinal pain.

Distribution of comorbidities in spondyloarthritis with regard to the phenotype and psoriasis: data from the ASAS-COMOSPA study

INTRODUCTION

The aim of the study was to compare the prevalence of comorbidities between patients with axial and peripheral phenotypes and to evaluate the role of psoriasis in such comorbidities.

METHODS

Patients from the cross-sectional Assessment in SpondyloArthritis Inter-national Society (ASAS)-COMOSPA study were classified as having either the axial (presence of sacroiliitis on X-ray or MRI) or peripheral phenotype (absence of sacroiliitis AND presence of peripheral involvement). Patients with each phenotype were divided into two groups depending on the presence or history of psoriasis. Pair-wise comparisons among the four groups (axial/peripheral phenotype with/without psoriasis) were conducted through univariate logistic regressions and generalized linear mixed models using disease duration and sex as fixed effects and country as random effect.

RESULTS

A total of 3291 patients were included in this analysis. The peripheral involvement with psoriasis phenotype showed the highest prevalence of hypertension (44.9%), dyslipidaemia (34%) and diabetes (8.8%), while the axial involvement without psoriasis phenotype exhibited the lowest prevalence of dyslipidaemia (14.2%), diabetes (4.1%) and stroke (0.9%). Among patients with psoriasis, the axial phenotype showed a significantly lower prevalence of hypertension (OR: 0.51, 95% CI: 0.35-0.75) and lower prevalence of Framingham score ⩾15 (OR: 0.57, 95% CI: 0.38-0.85) than patients with peripheral involvement after adjusting for disease duration, sex and country. Among patients with the axial phenotype, patients with psoriasis showed a higher prevalence of hypertension (OR 1.76, 1.40-2.20), dyslipidaemia (OR: 1.99, 95% CI: 1.56-2.53), diabetes (OR: 2.05, 95% CI: 1.39-3.02) and Framingham score ⩾15 (OR: 2.00, 95% CI: 1.57-2.55) than non-psoriatic patients. No differences were found across groups concerning bone metabolism disorders.

CONCLUSION

Both the peripheral phenotype and psoriasis are independently associated with an increased prevalence of cardiovascular risk factors. No differences were found for bone metabolism disorders.

Which factors explain the patient global assessment in patients with ankylosing spondylitis? A hierarchical cluster analysis on REGISPONSER-AS

OBJECTIVES

To determine groups of factors (clusters) potentially associated with the patient global assessment (measured with the Bath Ankylosing Spondylitis Patient Global Score (BAS-G)), and to quantify the contribution of each cluster to the patient's well-being.

METHODS

This was a cross-sectional study in patients with a diagnosis of ankylosing spondylitis (AS) from the national, multicentre Spanish REGISPONSER-AS registry. A hierarchical cluster analysis was conducted to group the potential factors (sociodemographic, socioeconomic, patient-reported outcomes, physical exploration variables and depression) associated with the BAS-G. The contribution of each cluster to the variability of the BAS-G was evaluated using a multivariate linear regression model and the determination coefficient (R²) for each cluster.

RESULTS

A total of 681 patients with complete data were included. Three clusters of variables potentially associated with the BAS-G were found: cluster 1 contained the Maastricht Ankylosing Spondylitis Enthesitis Score (MASES), depression, sex (female) and university studies; cluster 2 included the Graffar scale, age and body mass index; and cluster 3 contained the Bath Ankylosing Spondylitis Functional Index (BASFI), the individual items of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), pain during the last week, nocturnal pain and the number of swollen joints. A total of 6.8% of the variability of the BAS-G was explained by cluster 1, 0.5% was explained by cluster 2, and 60.8% was explained by cluster 3.

CONCLUSION

The BAS-G is mostly explained by pain and function, while demographic and socioeconomic factors are weakly associated with the BAS-G. Depression also has a weak effect on this score.

Prevalence and Associated Factors of Low Bone Mineral Density in the Femoral Neck and Total Hip in Axial Spondyloarthritis: Data from the CASTRO Cohort

Studies on osteoporosis in axial spondyloarthritis (axSpA) have focused on the lumbar segment, and few studies have assessed bone mineral density (BMD) in the hip and femoral neck in these patients. The aim of this study was to evaluate the prevalence of low BMD and osteopenia in the total hip or femoral neck and the factors associated with these conditions in axSpA patients. This was a single-centre, observational, cross-sectional study among consecutive patients with axSpA according to the ASAS criteria from the CASTRO registry. All patients underwent total hip and femoral neck DXA BMD measurements. Low BMD was defined as a Z-score less than −1, and osteopenia was defined as a T-score less than −1. Multivariate logistic and generalised linear regressions were used to evaluate factors independently associated with low BMD and osteopenia in the hip or femoral neck and those associated with variability in BMD, respectively. A total of 117 patients were included, among which 30.8% were female and the mean age was 45 years. A total of 36.0% of patients had low BMD (28.1% in the total hip and 27.4% in the femoral neck), and 56.0% of patients had osteopenia (44.7% in the total hip and 53.8% in the femoral neck). A multivariate logistic regression showed that age, radiographic sacroiliitis and ASAS-HI were independently associated with low BMD in the total hip or femoral neck. Factors that were independently associated with osteopenia were Body Mass Index, disease duration, radiographic sacroiliitis and ASAS-HI. In conclusion, 36% of the patients with axSpA had low BMD in the total hip or femoral neck. A younger age and radiographic sacroiliitis were the most important factors associated with decreased BMD.

Complement component 3 as biomarker of disease activity and cardiometabolic risk factor in rheumatoid arthritis and spondyloarthritis

Objective

To analyze the relationship between complement component 3 (C3) and the prevalence of cardiometabolic risk factors and disease activity in the rheumatic diseases having the highest rates of cardiovascular morbidity and mortality: rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA).

Methods

This is a cross-sectional study including 200 RA, 80 PsA, 150 axSpA patients and 100 healthy donors. The prevalence of cardiometabolic risk factors [obesity, insulin resistance, type 2 diabetes mellitus, hyperlipidemia, apolipoprotein B/apolipoprotein A (apoB/apoA) and atherogenic risks and hypertension] was analyzed. Serum complement C3 levels, inflammatory markers and disease activity were evaluated. Cluster analysis was performed to identify different phenotypes. Receiver operating characteristic (ROC) curve analysis to assess the accuracy of complement C3 as biomarker of insulin resistance and disease activity was carried out.

Results

Levels of complement C3, significantly elevated in RA, axSpA and PsA patients, were associated with the prevalence of cardiometabolic risk factors. Hard clustering analysis identified two distinctive phenotypes of patients depending on the complement C3 levels and insulin sensitivity state. Patients from cluster 1, characterized by high levels of complement C3 displayed increased prevalence of cardiometabolic risk factors and high disease activity. ROC curve analysis showed that non-obesity related complement C3 levels allowed to identify insulin resistant patients.

Conclusions

Complement C3 is associated with the concomitant increased prevalence of cardiometabolic risk factors in rheumatoid arthritis and spondyloarthritis. Thus, complement C3 should be considered a useful marker of insulin resistance and disease activity in these rheumatic disorders.

How to calculate the ASDAS based on C-reactive protein without individual questions from the BASDAI: the BASDAI-based ASDAS formula

OBJECTIVES

To develop a new equation to calculate the Ankylosing Spondylitis Disease Activity Score based on CRP (ASDAS-CRP) using only the BASDAI total score and CRP.

METHODS

Axial SpA (axSpA) patients from the Cordoba Spondyloarthritis Registry cohort were recruited as a derivation cohort, while a retrospective sample from the Spanish Rheumatology Society National Registry of Spondyloarthropathies and Ibero American Spondyloarhtritis Registry registers was used as a validation cohort. We built a new equation based only on the BASDAI and CRP, defining a new formula: the BASDAI-based ASDAS (BASDAS). Linear regression analysis was used to determine the coefficients of the equation in the derivation cohort and it was subsequently validated in the validation cohort.

RESULTS

A total of 52 axSpA patients in the derivation cohort and 3359 patients in the validation cohort were included. In the derivation cohort, the mean BASDAS [2.24 (s.d. 0.90)] was very similar to the ASDAS-CRP [2.23 (s.d. 0.95)], with a very strong correlation (r = 0.96, P < 0.001). In the validation cohort, the mean BASDAS was 3.31 (s.d. 1.37) and the ASDAS-CRP was 3.19 (s.d. 1.27), which also had a very strong correlation (r = 0.95, P < 0.001). Intraclass correlation coefficients were excellent in both cohorts (0.963 and 0.947, respectively).

CONCLUSION

The BASDAS performs similarly to the ASDAS-CRP and can be calculated with only the BASDAI total score and CRP, allowing evaluation of disease activity in retrospective studies where the individual items of the BASDAI are not available.