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.

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.

Peripheral spondyloarthritis: What have we learned?

The peripheral spondyloarthritis (pSpA) entity remains poorly defined in comparison with axial SpA and psoriatic arthritis, as the clinical symptoms have low specificity, the biological markers are virtually lacking, and dedicated randomized controlled trials in this specific indication remain scarce. In addition, clinical similarities between pSpA and psoriatic arthritis (PsA) have been described, partly explained by a resemblance in the pathophysiology of both entities. Thus, diagnosing pSpA can be challenging because of the overlap with other entities and the absence of a specific test or imaging study that can definitively diagnose the condition. The aim of this review is to summarize the current understanding of pSpA, its epidemiology, physiopathology, clinical diagnosis, and classification criteria. In addition, we present patient-reported outcomes used in pSpA clinical studies, available evidence on therapies, and future directions.

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.

Smoking and alcohol consumption are associated with peripheral musculoskeletal involvement in patients with spondyloarthritis (including psoriatic arthritis). Results from the ASAS-PerSpA study

BACKGROUND

An inverse association between alcohol consumption and disease activity and functional impairment has been observed in patients with spondyloarthritis (SpA). However, neither this association nor the influence of smoking has been investigated in peripheral manifestations of SpA.

OBJECTIVES

The objective of this study was to analyze the association between smoking and alcohol consumption and the presence of peripheral musculoskeletal manifestations (arthritis, enthesitis or dactylitis) and to determine the specific location of these manifestations.

METHODS

Patients from the worldwide cross-sectional ASAS-PerSpA study with a diagnosis of axial SpA (axSpA), peripheral SpA (pSpA) or psoriatic arthritis (PsA) according to their rheumatologist were included. Generalised linear mixed models used peripheral manifestation (or location) as a dependent variable, smoking status and alcohol consumption as fixed effects and country as a random effect. The interaction between smoking and alcohol was tested. Analyses were performed for each diagnosis (axSpA, pSpA and PsA).

RESULTS

A total of 4181 patients were included. In axSpA patients, smoking was associated with a lower prevalence of any peripheral manifestation, and current alcohol consumption was associated with a lower prevalence of both current arthritis and current enthesitis. In pSpA patients, current alcohol consumption was associated with a lower prevalence of current arthritis or enthesitis. In PsA patients, a significant association was found for arthritis with smoking and for enthesitis with alcohol consumption, and current alcohol consumption was associated with a lower prevalence of current arthritis or enthesitis.

CONCLUSION

Taking into account the country, smoking and alcohol are associated with a lower prevalence of peripheral manifestations.

Association between Carotid Intima-Media Thickness and the Use of Biological or Small Molecule Therapies in Patients with Rheumatoid Arthritis

Objective: The objective of this study was to assess the association of carotid intima-media thickness (CIMT), and also the presence of atheromatous plaque, with biological and targeted synthetic disease-modifying antirheumatic drugs, in an established cohort of patients with rheumatoid arthritis (RA). Patients and Methods: We conducted a cross-sectional observational study based on a cohort of patients with RA and a registry of healthy controls, in whom the CIMT and presence of atheromatous plaque were assessed by ultrasound. Data were collected on disease activity, lab results and treatments. Descriptive and bivariate analyses were performed and two multivariate linear regression models (with CIMT as the dependent variable) were constructed to identify variables independently associated with CIMT in our sample of patients with RA. Results: A total of 176 individuals (146 patients with RA and 30 controls) were included. A higher percentage of patients than controls had atheromatous plaque (33.8% vs. 12.5%, p = 0.036), but no differences were found in terms of CIMT (0.64 vs. 0.61, p = 0.444). Compared to values in patients on other therapies, the CIMT was smaller among patients on tumour necrosis factor alpha (TNFα) inhibitors (mean [SD]: 0.58 [0.10] vs. 0.65 [0.19]; p = 0.013) and among those on Janus kinase inhibitors (mean [SD]: 0.52 [0.02] vs. 0.64 [0.18]; p < 0.001), while no differences were found as a function of the use of the other therapies considered. The multivariate linear regression analysis to identify factors associated with CIMT in our patients, adjusting for traditional cardiovascular risk factors such as hypertension, high levels of low-density lipoproteins, diabetes mellitus and smoking, showed that male sex, older age and having a greater cumulative erythrocyte sedimentation rate were independently associated with a larger CIMT, while patients on TNFα inhibitors had a CIMT 0.075 mm smaller than those on other treatments. Conclusions: The use of TNFα inhibitors may protect against subclinical atherosclerosis in patients with RA, patients on this biologic having smaller CIMTs than patients on other disease-modifying antirheumatic drugs. Nonetheless, these results should be confirmed in prospective studies with larger sample sizes.

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.

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.

Uveitis as the first symptom in spondyloarthritis and its association with the evolution of the disease. Results from the REGISPONSER registry

OBJECTIVES

To describe the time of onset of acute anterior uveitis (AAU) relative to the appearance of rheumatic symptoms and to determine its association with the evolution of the spondyloarthritis (SpA) in terms of activity, structural damage, functional ability and treatment.

METHODS

This was a cross-sectional study with data extracted from the REGISPONSER (SpA Registry of the Spanish Rheumatology Society). Thirty-one centres participated, and patients with SpA according to the ESSG criteria were included from 2004 to 2007. Patients were classified according to the time of uveitis appearance with regard to rheumatic symptom onset (before, concomitant with, or after rheumatic symptom onset). We compared the clinical characteristics, disease activity, radiographic damage and functional ability between "AAU before or concomitant with rheumatic symptoms" and "AAU after rheumatic symptoms onset". Finally, we compared whether the time of appearance of AAU had an impact on the use of conventional and biological disease-modifying antirheumatic drugs (csDMARDs and bDMARDs, respectively).

RESULTS

A total of 2367 patients were included in REGISPONSER, with an AAU prevalence of 16.2% (379 patients). Patients with AAU before/concomitant with rheumatic symptom onset (n=59) exhibited better functional ability (BASFI, OR 0.85 [0.73-0.99]) and less structural damage (spinal BASRI, OR 0.88 [0.79-0.99]). Additionally, this group of patients was older at SpA symptom onset (OR 1.05 [1.02-1.09]) and had a shorter diagnosis delay (OR 0.90 [0.84-0.96]) compared patients with AAU after rheumatic symptom onset (n=229). No statistically significant differences in the use of DMARDs were noted (27.9% vs 23.2% for csDMARD use and 15.3% vs 20.3% for bDMARD use in patients with AAU before or concomitant with rheumatic symptom onset vs after rheumatic symptom onset, respectively).

CONCLUSION

Patients presenting with a first episode of AAU before/concomitant with the onset of rheumatic symptoms had less severe disease (better functional ability and less structural damage) and a shorter diagnosis delay; however, the time of AAU onset did not impact the treatments received.