The term ‘non-radiographic axial spondyloarthritis’ is much more important to classify than to diagnose patients with axial spondyloarthritis

Axial spondyloarthritis guidelines - aiming for maximum impact

PURPOSE OF REVIEW

This review discusses international clinical practice guidelines (CPGs) for axial spondyloarthritis (axSpA) focusing on methodology, guideline quality, and implementation.

RECENT FINDINGS

The Assessment of SpondyloArthritis International Society/European Alliance of Associations for Rheumatology (ASAS/EULAR) and Pan-American League of Associations for Rheumatology (PANLAR) recently published axSpA CPGs and updates of the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network (ACR/SAA/SPARTAN) and Asia-Pacific League of Associations for Rheumatology (APLAR) CPGs are expected. GRADE has emerged as the dominant framework for CPG development and has been used by three of the four international axSpA guidelines. Notable differences exist among these guidelines in the way that the recommendations are presented. Two of the four acknowledge the need for implementation strategies, but little detail about this is provided. The few studies that have evaluated the implementation of axSpA CPGs have identified poor adherence to recommendations on physical therapy/exercise and disease activity monitoring. Implementation science has identified many barriers and facilitators affecting guideline uptake, including those related to healthcare professionals and to the guidelines themselves. Creation of a tailored implementation plan simultaneously with the CPG is recommended.

SUMMARY

While methodological rigor in the creation of evidence-based recommendations is the focus of CPG development, recommendations must be presented in a user-friendly format that makes them easy to apply. 'Living guidelines' could facilitate keeping content up to date. Implementation is critical for the success of a CPG and should be emphasized in future axSpA guideline updates. Further research is needed to better understand the factors impacting the successful implementation of axSpA CPGs.

Clinical and structural damage outcomes in axial spondyloarthritis patients receiving NSAIDs or advanced therapies: a description of a real-life cohort

Introduction

This study aims to describe the clinical characteristics, disease activity, and structural damage in patients with axial spondyloarthritis (axSpA) who receive chronic treatment with nonsteroideal anti-inflammatory drugs (NSAIDs) or advanced therapies in a clinical setting.

Methods

Cross-sectional study on axSpA patients consecutively recruited from the outpatient clinic of a tertiary hospital. We collected data on clinical and demographic characteristics, as well as treatment patterns involving NSAIDs and advanced therapies. Structural damage was assessed using mSASSS.

Results

Overall, data from 193 axSpA patients (83% ankylosing spondylitis) were gathered, with a mean disease duration of 21.4 years. Of these, 85 patients (44%) were exclusively taking NSAIDs, while 108 (56%) were receiving advanced therapies, with TNF inhibitors being the predominant choice (93 out of 108, 86.1%). Among patients using NSAIDs, 64.7% followed an on-demand dosing regimen, while only 17.6% used full doses. Disease activity was low, with a mean BASDAI of 3.1 and a mean ASDAS-CRP of 1.8. In comparison to patients under chronic NSAID treatment, those taking advanced therapies were primarily male (69.4% versus 51.8%, p = 0.025) and significantly younger (mean age of 49 versus 53.9 years, p = 0.033). Additionally, patients on advanced therapies exhibited lower ASDAS-CRP (p = 0.046), although CRP serum levels and BASDAI scores did not differ between the two groups. In the multivariable analysis, therapy (NSAID versus biological treatment) was not independently associated with ASDAS-CRP, BASDAI or mSASSS.

Conclusion

This cross-sectional analysis of a real-world cohort of axSpA patients shows positive clinical and radiological outcomes for both NSAIDs and advanced therapies.

Can rheumatologists unequivocally diagnose axial spondyloarthritis in patients with chronic back pain of less than 2 years duration? Primary outcome of the 2-year SPondyloArthritis Caught Early (SPACE) cohort

OBJECTIVES

To investigate the prevalence of axial spondyloarthritis (axSpA) in patients with chronic back pain (CBP) of less than 2 years (2y) duration referred to the rheumatologist, the development of diagnosis over time, and patient characteristics of those developing definite (d-)axSpA over 2y.

METHODS

We analysed the 2y data from SPondyloArthritis Caught Early, a European cohort of patients (<45 years) with CBP (≥3 months, ≤2y) of unknown origin. The diagnostic workup comprised evaluation of clinical SpA features, acute phase reactants, HLA-B27, radiographs and MRI (sacroiliac joints and spine), with repeated assessments. At each visit (baseline, 3 months, 1y and 2y), rheumatologists reported a diagnosis of axSpA or non-axSpA with level of confidence (LoC; 0-not confident at all to 10-very confident).

MAIN OUTCOME

axSpA diagnosis with LoC≥7 (d-axSpA) at 2y.

RESULTS

In 552 patients with CBP, d-axSpA was diagnosed in 175 (32%) at baseline and 165 (30%) at 2y. Baseline diagnosis remained rather stable: at 2y, baseline d-axSpA was revised in 5% of patients, while 8% 'gained' d-axSpA. Diagnostic uncertainty persisted in 30%. HLA-B27+ and baseline sacroiliitis imaging discriminated best 2y-d-axSpA versus 2y-d-non-axSpA patients. Good response to non-steroidal anti-inflammatory drugs and MRI-sacroiliitis most frequently developed over follow-up in patients with a new d-axSpA diagnosis. Of the patients who developed MRI-sacroiliitis, 7/8 were HLA-B27+ and 5/8 male.

CONCLUSION

A diagnosis of d-axSpA can be reliably made in nearly one-third of patients with CBP referred to the rheumatologist, but diagnostic uncertainty may persist in 5%-30% after 2y. Repeated assessments yield is modest, but repeating MRI may be worthwhile in male HLA-B27+ patients.

The role of ixekizumab in the treatment of nonradiographic axial spondyloarthritis

Nonradiographic axial spondyloarthritis (nr-axSpA) is a subtype of SpA with undeveloped definite radiographic sacroiliitis. Tumor necrosis factor inhibitors have demonstrated effectiveness in nr-axSpA patients who do not respond to first-line therapy. More recently, accumulated data from genetic, experimental, and clinical studies revealed that IL-17 is a key player in the pathogenesis of SpA, leading to development of new biologics directly inhibiting IL-17. Among them, ixekizumab is a high-affinity monoclonal antibody that selectively targets IL-17A and has exhibited significant efficacy and acceptable safety profiles in the treatment of nr-axSpA. The aim of this paper is to narratively review the recent insights of IL-17 in the pathogenesis of axSpA and discuss the effectiveness and safety of ixekizumab in treatment of nr-axSpA.

A Good Response to Nonsteroidal Antiinflammatory Drugs Does Not Discriminate Patients With Longstanding Axial Spondyloarthritis From Controls With Chronic Back Pain

OBJECTIVE

To compare the response to nonsteroidal antiinflammatory drugs (NSAIDs) in patients with longstanding axial spondyloarthritis (axSpA) and controls with back pain (nonspondyloarthritis [non-SpA]).

METHODS

Consecutive outpatients with chronic back pain (axSpA or non-SpA), were prospectively recruited. Any previous NSAIDs were withdrawn 2 days before study start (baseline). Back pain was assessed using a numerical rating scale (NRS; range 0-10) starting at 2 hours after baseline and several times thereafter up to 4 weeks. "Any response" to NSAIDs was defined as improvement of back pain on the NRS > 2 units, and "good response" as improvement > 50%, compared to baseline.

RESULTS

Among 233 patients included, 68 had axSpA (29.2%) and 165 had non-SpA back pain (70.8%). The mean age was 42.7 (SD 10.7) vs 49.3 (SD 11.1) years, symptom duration 15.1 (SD 11.1) years vs 14.6 (SD 11.9) years, and pain score 5.9 (SD 2.3) vs 6.3 (SD 2.0), respectively. Overall, of patients with axSpA or non-SpA back pain, 30.9% vs 29.1% of patients showed any response and 23.5% vs 16.4% of patients showed a good response after 4 weeks, respectively (P value not significant). No differences were found in the rapidity of response or between subgroups of patients based on demographics, including different stages of axSpA.

CONCLUSION

No major differences in the response to NSAIDs were found between patients with axSpA and those with non-SpA with longstanding chronic back pain. The item in the Assessment of SpondyloArthritis international Society classification criteria on "response to NSAIDs" needs more study.

The cost-effectiveness of a bimekizumab versus IL-17A inhibitors treatment-pathway in patients with active axial spondyloarthritis in Scotland

OBJECTIVE

To estimate the cost-effectiveness of a treatment-pathway initiated with bimekizumab, a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F and IL-17A, in patients with axial spondyloarthritis (axSpA) compared with IL-17Ai's, ixekizumab, and secukinumab, from the NHS Scotland perspective.

METHODS

The axSpA treatment-pathway was modeled using a decision tree followed by a lifetime Markov model. The pathway included first- and second-line biologic disease-modifying antirheumatic drugs (bDMARD), followed by best supportive care (bDMARD, nonbiologic). Bimekizumab followed by any bDMARD ("BKZ") was compared with IL-17Ai's: secukinumab 150 mg followed by a blend ("SEC") of dose up-titration to secukinumab 300 mg and any bDMARD, or ixekizumab followed by any bDMARD ("IXE"). Transition to the next therapy was triggered by Bath Ankylosing Spondylitis Disease Activity Index-50% (BASDAI50) non-response or any-cause discontinuation. A published network meta-analysis provided efficacy data. EuroQoL-5-dimensions utilities were derived by mapping from Ankylosing Spondylitis Disease Activity Score. Costs included disease management (linked to functional limitations), biologics acquisition (list prices), administration and monitoring (NHS 2021/22). Discounting was 3.5%/year. Probabilistic results from patients with non-radiographic axSpA and ankylosing spondylitis were averaged to reflect the axSpA disease spectrum. Scenario and sensitivity analyses were performed.

RESULTS

The incremental cost-effectiveness ratio (ICER) of BKZ was £24,801/quality-adjusted life-year (QALY) vs. SEC (95% credible interval £24,163-£25,895). BKZ had similar costs (Δ -£385 [-£15,239-£14,468]) and QALYs (Δ 0.039 [-0.748-0.825]) to IXE, with £1,523 (£862-£2,222) net monetary benefit. Conclusions remained unchanged in most scenarios. Results' drivers included BASDAI50 response rate and disease management cost.

LIMITATIONS

Results were based on list prices. Data concerning up-titration to secukinumab 300 mg was scarce.

CONCLUSIONS

The bimekizumab treatment-pathway represents a cost-effective option across the axSpA disease spectrum in Scotland. Bimekizumab is cost-effective compared to a secukinumab-pathway that includes dose up-titration, and has similar costs and QALYs to an ixekizumab-pathway.

The Development and Validation of an AI Diagnostic Model for Sacroiliitis: A Deep-Learning Approach

PURPOSE

Sacroiliitis refers to the inflammatory condition of the sacroiliac joints, frequently causing lower back pain. It is often associated with systemic conditions. However, its signs on radiographic images can be subtle, which may result in it being overlooked or underdiagnosed. This study aims to utilize artificial intelligence (AI) to create a diagnostic tool for more accurate sacroiliitis detection in radiological images, with the goal of optimizing treatment plans and improving patient outcomes.

MATERIALS AND METHOD

The study included 492 patients who visited our hospital. Right sacroiliac joint films were independently evaluated by two musculoskeletal radiologists using the Modified New York criteria (Normal, Grades 1-4). A consensus reading resolved disagreements. The images were preprocessed with Z-score standardization and histogram equalization. The DenseNet121 algorithm, a convolutional neural network with 201 layers, was used for learning and classification. All steps were performed on the DEEP:PHI platform.

RESULT

The AI model exhibited high accuracy across different grades: 94.53% (Grade 1), 95.83% (Grade 2), 98.44% (Grade 3), 96.88% (Grade 4), and 96.09% (Normal cases). Sensitivity peaked at Grade 3 and Normal cases (100%), while Grade 4 achieved perfect specificity (100%). PPVs ranged from 82.61% (Grade 1) to 100% (Grade 4), and NPVs peaked at 100% for Grade 3 and Normal cases. The F1 scores ranged from 64.41% (Grade 1) to 95.38% (Grade 3).

CONCLUSIONS

The AI diagnostic model showcased a robust performance in detecting and grading sacroiliitis, reflecting its potential to enhance diagnostic accuracy in clinical settings. By facilitating earlier and more accurate diagnoses, this model could substantially impact treatment strategies and patient outcomes.

Short-Term Efficacy and Adverse Effects of Sulfasalazine in the Management of Axial Spondyloarthropathy

INTRODUCTION

Ankylosing spondylitis (AS) is an inflammatory spondyloarthropathy that involves the sacroiliac joints and the axial skeleton. Sulfasalazine's efficacy in treating the axial symptoms of AS has been a subject of controversy.

METHODS

This prospective observational study recruited AS patients and categorized them into two groups: the first group had AS for less than or equal to four years and the second group had AS for more than four years. Erythrocytic sedimentation rate (ESR) and C-reactive protein (CRP) levels were recorded at baseline and at six-month follow-up. Disease severity was assessed using the ankylosing spondylitis disease activity score (ASDAS), Bath ankylosing spondylitis disease activity index (BASDAI) score, and Bath ankylosing spondylitis functional index (BASFI) score.

RESULTS

A total of 33 patients diagnosed with AS were recruited in this study, mostly males (88%) and within 21-30 years of age. ESR and CRP values were measured at baseline and at six months post-treatment with sulfasalazine. Mean ESR and mean CRP values showed a statistically significant reduction of 43.5% (p=0.001) and 58.45% (p=0.0012) respectively, at the 6-month follow-up. Four patients (12.12%) reported gastrointestinal intolerance. The mean reduction in the ASDAS score was 24% (p=0.002), the BASDAI score was 40.08% (p=0.001), and the BASFI score was 39.54% (p=0.01). Additionally, the duration of symptoms did not appear to influence with efficacy of sulfasalazine.

DISCUSSION

Sulfasalazine is a safe alternative therapy for patients with AS who cannot afford biologics, due to its reasonable short-term efficacy, good tolerability, cost-effective nature, and low incidence of adverse effects.

Current Pharmacological Therapies for the Management of Spondyloarthritis: Special Considerations in Older Patients

Spondylarthritis (SpA) is generally observed in young male patients but can be diagnosed in older patients. These cases correspond to late-onset SpA (LoSpA) with two main clinical presentations, axial and peripheral SpA. Another increasingly common situation is that of older patients who have had SpA for many years. The therapeutic management of LoSpA is quite smilar to the management of patients with an early-onset disease, combining both non-pharmacological and pharmacological treatments. The treatments that can be used in LoSpA include non-steroidal anti-inflammatory drugs (NSAIDs) and biological agents targeting TNFα or IL-17A. Janus kinase inhibitors (JAKi) were recently introduced on the market for SpA. TNF inhibitors and IL-17inhibitors are very effective drugs in early-onset SpA. The effectiveness and safety of targeted therapies have not been specifically evaluated in LoSpA or older patients, and thus caution is required for these patients with comorbidities and/or polymedication. According to indirect data, biological agents seem to be less effective in LoSpA compared with early-onset disease. In parallel, a careful evaluation for the risk of infection, malignancy and cardiovascular events is recommended before initiating these drugs in this age category. JAKi may be used in LoSpA, but only in selected patients according to recent recommendations from the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). When considering that the prevalence of such situations is expected to increase as ageing progresses, it is certainly time to consider this patient category as a distinct subgroup within the spectrum of SpA. Specific studies evaluating targeted agents in this age category are thus desirable.

Mitochondrial displacement loop region single nucleotide polymorphisms and mitochondrial DNA copy number associated with risk of ankylosing spondylitis

AIM

The pathogenesis of ankylosing spondylitis (AS) seems to be associated with genetics, the environment, heredity, and oxidative stress. Single nucleotide polymorphisms (SNPs) in the displacement loop (D-loop) region of mitochondrial DNA (mtDNA) and mtDNA copy number were investigated for their correlation with AS patients.

METHODS

This study included 83 AS patients and 100 healthy controls from the Second Hospital of Hebei Medical University. DNAs were extracted from blood samples for polymerase chain reaction analysis and quantitative real-time polymerase chain reaction analysis. Plasma reactive oxygen species (ROS) levels were measured by fluorescent probe technology.

RESULTS

The distribution frequencies of the minor alleles of nucleotides 16304C (p = .037), 16311C (p = .027), and 152C (p = .034) were remarkably higher in AS patients than in healthy controls, which indicated that the16304C, 16311C, and 152C alleles were correlated with an increased risk of AS. Simultaneously, mtDNA copy number was statistically higher in patients with AS compared with controls (1.450 ± 0.876 versus 0.835 ± 0.626, p < .001). We also observed an increased ROS generation in AS patients compared with controls (27 066.169 ± 18 364.819 versus 14 758.330 ± 5854.946, p < .001) subsequently. In addition, the AS susceptible SNP 16311C is associated with high ROS levels (35 065.177 ± 26 999.934 vs. 25 005.818 ± 14 999.495, p = .043).

CONCLUSION

Our study demonstrated that SNPs in the mtDNA D-loop could be AS risk biomarkers with the potential to promote oxidative stress levels; mtDNA copy number-induced mitochondrial dysfunction may also be involved in AS pathogenesis.

The Effects of Pilates Exercise Training Combined with Walking on Cardiorespiratory Fitness, Functional Capacity, and Disease Activity in Patients with Non-Radiologically Confirmed Axial Spondylitis

The objective of the study was to examine the effects of Pilates exercise training combined with walking on cardiorespiratory fitness, functional capacity, and disease activity in patients with non-radiologically confirmed axial spondylitis (nr-axSpA). Thirty patients with nr-axSpA (seven women (90%), with a mean age of 46.07 ± 10.48 years old and C-reactive protein (CRP) 2.26 ± 2.14 mg/L) were randomly divided into two groups: A (n1 = 15 patients) and B (n2 = 15 patients). Group A followed a 6-month home-based Pilates exercise training program, while Group B remained untrained until the end of the study. A cardiopulmonary exercise test (CPET), timed up and go test (TUG), five times sit-to-stand test (5×STS), sit-and-reach test (SR), back scratch test for the right (BSR) and the left arm (BSL), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and Ankylosing Spondylitis Disease Activity Score (ASDAS) were applied to all patients, both at the beginning and at the end of the study. After 6 months, Group A showed higher values in exercise time by 37.41% (p = 0.001), higher peak oxygen uptake (VO2peak) by 25.41% (p = 0.01), a higher ratio between oxygen uptake and maximum heart rate (VO2/HRmax) by 14.83% (p = 0.04), and higher SR by 18.70% (p = 0.007), while lower values were observed in TUG by 24.32% (p = 0.001), 5×STS by 12.13% (p = 0.001), BASDAI score by 20.00% (p = 0.04) and ASDAS score by 23.41% (p = 0.03), compared to Group B. Furthermore, linear regression analysis showed a positive correlation in Group A between BASDAI and 5×STS (r = 0.584, p = 0.02), BASDAI and TUG (r = 0.538, p = 0.03), and ASDAS and 5×STS (r = 0.538, p = 0.03), while a negative correlation was found between BASDAI and VO2peak (r = -0.782, p < 0.001), ASDAS and SR (r = -0.548, p = 0.03), and ASDAS and VO2peak (r = -0.659, p = 0.008). To sum up, cardiorespiratory fitness, functional capacity, and disease activity improved after a long-term Pilates exercise training program in patients with nr-axSpA.

Peripheral CD4+ /CD8+ T cell composition distinct from healthy individuals is shared by ankylosing spondylitis and rheumatoid arthritis

OBJECTIVE

Ankylosing spondylitis (AS) and rheumatoid arthritis (RA) are chronic inflammatory joint diseases, linking to the alterations of immune cells. We attempted to assess whether the alterations in the composition of CD4+ /CD8+ T cells are different between AS and RA and identify the characteristic cells between male and female patients.

METHODS

The proportions of CD3+ or double positive T cells, 6 CD4+ T subsets and 9 CD8+ T cell subsets were detected by flow cytometry and compared in 30 healthy individuals, 42 AS patients and 45 RA patients. The differentially altered cells were individually analyzed for associations with disease activity parameters. In addition, their proportions were compared between different genders in the 3 groups.

RESULTS

The proportions of CD4+ T cells, naive CD4+ T cells and central memory CD4+ T cells were lower in AS patients (P = 0.001, P = 0.002 and P = 0.007, respectively) and RA patients (P = 0.032, P < 0.001 and P = 0.016, respectively), but the proportion of effector memory ones was higher when compared with healthy populations (both P < 0.001), as were the decrease of naive/central memory CD8+ T cells in AS (P = 0.003 and P = 0.016, respectively) and RA (P < 0.001 and P = 0.006, respectively), and the increased tendency of terminally differentiated CD8+ T cells. However, these above-mentioned cells, regulatory T (Treg) cells and CD8+ T cells with different CD127 expressions between AS and RA were similar in proportion. Furthermore, naive CD4+ T cells were positively associated with C-reactive protein (CRP) in AS, whereas CD4+ T cells and terminally differentiated CD8+ T of RA patients were associated with CRP in RA. The gender-related alterations predominantly displayed the overexpressions of Treg cells and naive CD8+ T cells in female patients with AS and RA, respectively.

CONCLUSIONS

AS patients and RA patients have some similar peripheral CD4+ /CD8+ T cell subsets but are distinct from healthy individuals, which may contribute to disease severity. Females are respectively characterized by the up-regulation of Treg cells and naive CD8+ T cells in AS patients and RA patients. The study offers an in-depth understanding of the role of T cell subsets in the similarities of the disorders and helps us to monitor disease changes and may offer a theoretical basis of developing novel therapies against common targets.

Advances in pharmacotherapies for axial spondyloarthritis

INTRODUCTION

Axial spondyloarthritis (axSpA) refers to an inflammatory rheumatic disease that mainly affects the axial skeleton and leads to progressive radiographic changes of the sacroiliac joints and spine. axSpA is currently subdivided into the radiographic (r-axSpA) and non-radiographic (nr-axSpA) form. Both forms are associated with musculoskeletal pain, restriction of spinal mobility, specific extra-musculoskeletal manifestations, and overall, altered quality of life. The therapeutic management of axSpA is currently well standardized.

AREAS COVERED

We reviewed available literature (by using PubMed search) on non-pharmacological and pharmacological treatment options that may be used in axSpA, including r-axSpA and nr-axSpA, as well as the role of non-steroidal anti-inflammatory drugs (NSAIDs), biological agents including TNFalpha (TNFi) and IL-17 (IL-17i) inhibitors. New treatment options such as Janus kinase inhibitors are also reviewed.

EXPERT OPINION

NSAIDs remain the mainstay of initial therapy, and subsequently, biological agents (TNFi and IL-17i) may be envisaged. Four TNFi are licensed for the treatment of both r-axSpA and nr-axSpA, while IL-17i are approved in each indication. The choice between a TNFi and an IL-17i is mainly guided by the presence of extra-articular manifestations. JAKi were more recently introduced for the treatment of r-axSpA, but their use is restricted to specific patients with a safe cardiovascular profile.

Prevalence and complication of COVID-19 in patients with ankylosing spondylitis (AS) and its relationship with TNF-a inhibitors

INTRODUCTION

Ankylosing spondylitis (AS) is a condition that is treated with nonsteroidal anti-inflammatory drugs and biological drugs such as anti tumor necrosis factor alpha (TNF-α). This study examined the prevalence of COVID-19 among individuals with AS and compare it between those receiving and not receiving TNF-α inhibitors.

METHODS

A cross-sectional study was conducted at the rheumatology clinic of Imam Khomeini Hospital in Tehran, Iran. The study included patients with AS who sought treatment at the clinic. Demographic information, laboratory and radiographic findings, and disease activity were recorded through interviews and examinations using a questionnaire.

RESULTS

A total of 40 patients were studied over the course of 1 year. Among them, 31 patients were administered anti-TNF-α drugs, with 15 patients (48.3%) receiving subcutaneous Altebrel (Etanercept), 3 patients (9.6%) receiving intravenous Infliximab, and 13 patients (41.9%) receiving subcutaneous Cinnora (Adalimumab). Of the total, 7 patients (17.5%) tested positive for COVID-19, 1 of whom was confirmed through both CT scan and polymerase chain reaction (PCR) testing, while the remaining 6 patients were confirmed only through PCR testing. All patients tested positive for COVID-19 were male, and 6 of them had received Altebrel. Among the 9 AS patients who did not receive TNF inhibitors, 1 patient contracted SARS-CoV-2. The clinical symptoms experienced by these patients were mild, and hospitalization was not required. However, 1 patient who had insulin-dependent type 1 diabetes and was receiving Infliximab required hospitalization. This patient exhibited more severe COVID-19 symptoms, including high fever, pulmonary involvement, dyspnea, and decreased oxygen saturation. No cases of COVID-19 were reported in the Cinnora treatment group. The use of any of the drugs did not demonstrate a significant relationship with the occurrence of COVID-19 in patients.

CONCLUSIONS

The use of the TNF-α inhibitors in patients with AS, may be associated with reduced hospitalization and death rate in COVID-19 cases.

Two-year imaging outcomes from a phase 3 randomized trial of secukinumab in patients with non-radiographic axial spondyloarthritis

BACKGROUND

Radiographic progression and course of inflammation over 2 years in patients with non-radiographic axial spondyloarthritis (nr-axSpA) from the phase 3, randomized, PREVENT study are reported here.

METHODS

In the PREVENT study, adult patients fulfilling the Assessment of SpondyloArthritis International Society classification criteria for nr-axSpA with elevated CRP and/or MRI inflammation received secukinumab 150 mg or placebo. All patients received open-label secukinumab from week 52 onward. Sacroiliac (SI) joint and spinal radiographs were scored using the modified New York (mNY) grading (total sacroiliitis score; range, 0-8) and modified Stoke Ankylosing Spondylitis Spine Score (mSASSS; range, 0-72), respectively. SI joint bone marrow edema (BME) was assessed using the Berlin Active Inflammatory Lesions Scoring (0-24) and spinal MRI using the Berlin modification of the AS spine MRI (ASspiMRI) scoring (0-69).

RESULTS

Overall, 78.9% (438/555) of patients completed week 104 of the study. Over 2 years, minimal changes were observed in total radiographic SI joint scores (mean [SD] change, - 0.04 [0.49] and 0.04 [0.36]) and mSASSS scores (0.04 [0.47] and 0.07 [0.36]) in the secukinumab and placebo-secukinumab groups. Most of the patients showed no structural progression (increase ≤ smallest detectable change) in SI joint score (87.7% and 85.6%) and mSASSS score (97.5% and 97.1%) in the secukinumab and placebo-secukinumab groups. Only 3.3% (n = 7) and 2.9% (n = 3) of patients in the secukinumab and placebo-secukinumab groups, respectively, who were mNY-negative at baseline were scored as mNY-positive at week 104. Overall, 1.7% and 3.4% of patients with no syndesmophytes at baseline in the secukinumab and placebo-secukinumab group, respectively, developed ≥ 1 new syndesmophyte over 2 years. Reduction in SI joint BME observed at week 16 with secukinumab (mean [SD], - 1.23 [2.81] vs - 0.37 [1.90] with placebo) was sustained through week 104 (- 1.73 [3.49]). Spinal inflammation on MRI was low at baseline (mean score, 0.82 and 1.07 in the secukinumab and placebo groups, respectively) and remained low (mean score, 0.56 at week 104).

CONCLUSION

Structural damage was low at baseline and most patients showed no radiographic progression in SI joints and spine over 2 years in the secukinumab and placebo-secukinumab groups. Secukinumab reduced SI joint inflammation, which was sustained over 2 years.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02696031.

A Cross-Indication Budget Impact Model of Secukinumab for the Treatment of Psoriasis, Psoriatic Arthritis, Ankylosing Spondylitis and Non-radiographic Axial Spondyloarthritis in Italy

BACKGROUND

Recent developments improved outcomes in patients with autoimmune diseases. Biologics were approved as first-line treatment in selected naïve patients with plaque psoriasis (PsO), psoriatic arthritis (PsA), ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-axSpA). Among them, secukinumab was most recently approved for treatment of active nr-axSpA in adults. In this work, we assessed the budget impact of new secukinumab treatment options in the Italian market.

METHODS

A cross-indication budget impact model was designed to estimate the effects of adding secukinumab in the Italian market from the National Health System perspective over a 3-year period. The model included all adults with PsO, PsA, AS and nr-axSpA, treated with biologics or biosimilars. It compared costs between two scenarios, secukinumab availability or absence, for the four diseases combined and taken individually. A sensitivity analyses was conducted.

RESULTS

There were 68,121 adult patients treated with biologics in 2021 and 68,341 in 2023. The budget impact analysis (BIA) on all indications showed a cost reduction of €33.7 million (- 1.5%) over 3 years with the introduction of secukinumab. PsA patients had the highest saving (- €34.9 million), followed by PsO patients (- €7.8 million). Cost saving in PsO patients was balanced by increased budget reported in AS patients (+ €8.0 million). In nr-axSpA patients, secukinumab reported no significant budget increase (+ 1.0%).

CONCLUSION

This BIA accounted for the new indication of secukinumab in nr-axSpA patients, reporting no significant changes in the required budget and adding an effective treatment option. Considering all indications, secukinumab is a sustainable treatment option.

Deep learning methods in the diagnosis of sacroiliitis from plain pelvic radiographs

OBJECTIVES

The aim of this study is to develop a computer-aided diagnosis method to assist physicians in evaluating sacroiliac radiographs.

METHODS

Convolutional neural networks, a deep learning method, were used in this retrospective study. Transfer learning was implemented with pre-trained VGG-16, ResNet-101 and Inception-v3 networks. Normal pelvic radiographs (n = 290) and pelvic radiographs with sacroiliitis (n = 295) were used for the training of networks.

RESULTS

The training results were evaluated with the criteria of accuracy, sensitivity, specificity and precision calculated from the confusion matrix and AUC (area under the ROC curve) calculated from ROC (receiver operating characteristic) curve. Pre-trained VGG-16 model revealed accuracy, sensitivity, specificity, precision and AUC figures of 89.9%, 90.9%, 88.9%, 88.9% and 0.96 with test images, respectively. These results were 84.3%, 91.9%, 78.8%, 75.6 and 0.92 with pre-trained ResNet-101, and 82.0%, 79.6%, 85.0%, 86.7% and 0.90 with pre-trained inception-v3, respectively.

CONCLUSIONS

Successful results were obtained with all three models in this study where transfer learning was applied with pre-trained VGG-16, ResNet-101 and Inception-v3 networks. This method can assist clinicians in the diagnosis of sacroiliitis, provide them with a second objective interpretation and also reduce the need for advanced imaging methods such as magnetic resonance imaging.

ASAS-EULAR recommendations for the management of axial spondyloarthritis: 2022 update

OBJECTIVES

To update the Assessment of SpondyloArthritis international Society (ASAS)-EULAR recommendations for the management of axial spondyloarthritis (axSpA).

METHODS

Following the EULAR Standardised Operating Procedures, two systematic literature reviews were conducted on non-pharmacological and pharmacological treatment of axSpA. In a task force meeting, the evidence was presented, discussed, and overarching principles and recommendations were updated, followed by voting.

RESULTS

Five overarching principles and 15 recommendations with a focus on personalised medicine were agreed: eight remained unchanged from the previous recommendations; three with minor edits on nomenclature; two with relevant updates (#9, 12); two newly formulated (#10, 11). The first five recommendations focus on treatment target and monitoring, non-pharmacological management and non-steroidal anti-inflammatory drugs (NSAIDs) as first-choice pharmacological treatment. Recommendations 6-8 deal with analgesics and discourage long-term glucocorticoids and conventional synthetic disease-modifying antirheumatic drugs (DMARDs) for pure axial involvement. Recommendation 9 describes the indication of biological DMARDs (bDMARDs, that is, tumour necrosis factor inhibitors (TNFi), interleukin-17 inhibitors (IL-17i)) and targeted synthetic DMARDs (tsDMARDs, ie, Janus kinase inhibitors) for patients who have Ankylosing Spondylitis Disease Activity Score ≥2.1 and failed ≥2 NSAIDs and also have either elevated C reactive protein, MRI inflammation of sacroiliac joints or radiographic sacroiliitis. Current practice is to start a TNFi or IL-17i. Recommendation 10 addresses extramusculoskeletal manifestations with TNF monoclonal antibodies preferred for recurrent uveitis or inflammatory bowel disease, and IL-17i for significant psoriasis. Treatment failure should prompt re-evaluation of the diagnosis and consideration of the presence of comorbidities (#11). If active axSpA is confirmed, switching to another b/tsDMARD is recommended (#12). Tapering, rather than immediate discontinuation of a bDMARD, can be considered in patients in sustained remission (#13). The last recommendations (#14, 15) deal with surgery and spinal fractures.

CONCLUSIONS

The 2022 ASAS-EULAR recommendations provide up-to-date guidance on the management of patients with axSpA.

Facet Joint Involvement in Early MRI Positive Axial Spondyloarthritis

Background The disease course of non-radiographic axial spondyloarthritis (nr-axSpA), usually detected by magnetic resonance imaging (MRI), is often unclear at the time of diagnosis. We investigated which MRI findings in the sacroiliac joints (SIJs) and lumbar spine including the facet joints can be observed over a two-year period in patients with newly diagnosed active inflammatory lesions in the SIJs fufilling the Assessment of SpondyloArthritis International Society criteria (ASAS) for Axial Spondyloarthritis (axSpA).

Methods Patients (n=56, age<45 years, 30 female and 26 male, symptom duration 3–30 months) consecutively diagnosed with unilateral or bilateral sacroiliitis through MRI during an 18-month period and meeting the ASAS criteria for axial SpA were followed up for two years. Clinical examination, laboratory tests and an MRI of the sacroiliac joints (SIJs), lumbar spine and facet joints were performed at diagnosis (t0), after one year (t1) and after two years (t2).

Results At t0, 31 patients (55%) with a bone marrow edema (BME) in the SIJs already had detectable changes in the facet joints, including signs of inflammation or degenerative changes. At t2, patients with facet joint involvement in t0 not only had more significant changes in the SIJs but also significantly more changes in the vertebral bodies, including BME, fat lesions and vertebral body erosions than patients without changes in the facet joints at t0. All vertebral changes described might be potential indicators of progression to radiographic axSpA (r-axSpA). These MRI findings are seen more frequently over a short period of time than previously thought.

Conclusions MRI progression in the SIJs over a two-year period is associated with increasing damage to the facet joints and vertebral bodies. Involvement of the facet joints in the early stages of the disease may indicate increasing changes in the vertebral bodies and thus a less favourable course of axSpA.

Significance of structural changes in the axial skeleton in patients with axial spondyloarthritis: how important are lesions in the sacroiliac joint?

Inflammatory back pain (IBP) is a characteristic clinical symptom of patients with axial spondyloarthritis (axSpA) that is caused by inflammation in the axial skeleton. In early disease stages the sacroiliac joints (SIJ) are most often affected, the spine usually at later stages. In many but clearly not all cases of axSpA new bone formation in form of syndesmophytes and ankylosis occur in the further course of the disease. Function and mobility may be impaired by both, inflammation and structural changes. In clinical trials outcome parameters most often used refer to pain, disease activity, function, mobility and global health but many researchers are also interested in radiographic progression in the axial skeleton of patients with axSpA. This viewpoint discusses the relevance of structural changes in the SIJ in comparison to the spine and in relation to functional outcomes and mobility.

Efficacy and safety of ixekizumab treatment in patients with axial spondyloarthritis: 2-year results from COAST

OBJECTIVES

To study the efficacy and safety of ixekizumab (IXE) in patients with radiographic (r-) and non-radiographic (nr-)axial spondyloarthritis (axSpA) for up to 116 weeks.

METHODS

COAST-Y (NCT03129100) is the 2-year extension study following COAST-V, COAST-W and COAST-X. Patients were treated with either 80 mg IXE every 4 weeks or 2 weeks, as assigned in the originating studies. Efficacy was assessed in all participants continuously treated with IXE through week 116 and in subgroups based on disease subtype and dosing. Missing data were handled by non-responder imputation for categorical variables and modified baseline observation carried forward for continuous variables. Safety data were analysed in all patients having received ≥1 IXE dose.

RESULTS

Of 932 patients who received ≥1 IXE dose, 773 enrolled in COAST-Y (82.9%); 665 of which (86.0%) completed week 116. Of 352 continuously treated patients, the proportion achieving Assessment of Spondyloarthritis International Society (ASAS40) at week 52 was 51.4%, which increased to 56.0% at week 116. The proportion of patients achieving ASAS40 at week 116 was 64.9% and 57.7% for biological disease-modifying antirheumatic drug (bDMARD)-naïve patients with r-axSpA and nr-axSpA, respectively, and 47.0% for TNFi-experienced patients. The proportion of patients achieving Ankylosing Spondylitis Disease Activity Score <2.1 through week 116 was 57.0% and 52.9% for bDMARD-naïve patients with r-axSpA and nr-axSpA, respectively, and 33.6% for TNFi-experienced patients. Incidences of treatment-emergent adverse events and serious adverse events were consistent with previous reports.

CONCLUSION

IXE treatment led to sustained long-term improvements in patients with axSpA, with similar efficacy for r-axSpA and nr-axSpA, and for patients receiving the approved every 4 weeks dose. The safety profile of IXE was consistent with previous reports. No new safety signals were identified.

Postoperative Use of Biologics was Less Common among Patients with Crohn's Disease With Emergent/Urgent Versus Elective Intestinal Resection

Background & Aims

Given the risk of intestinal resection for Crohn's disease, postoperative treatment may be informed by several risk factors, including resection type. We compared postoperative treatment strategies for Crohn's disease between emergent/urgent versus elective resection.

Methods

We identified patients with intestinal resection for Crohn's disease between 2002-2018 using the MarketScan databases. We classified emergent/urgent resections as those occurring after emergency department admission or after the second day of admission. We estimated adjusted risk differences for the association between resection type (emergent/urgent versus elective) and 6-month postoperative medication strategy (biologic monotherapy, biologic combination therapy with an immunomodulator, immunomodulator monotherapy, other non-biologic medication for Crohn's [5-aminosalicylates, antibiotics, corticosteroids], or no medications for Crohn's).

Results

During 6 months after resection among 4,187 patients, 23% received biologic monotherapy, 6% received combination therapy, 16% received immunomodulator monotherapy, and 36% received other non-biologics. Compared to elective resection, emergent/urgent resection was associated with more common use of "other non-biologic" medications (risk difference 6.4%; 95% confidence interval [CI] 2.8%, 10.0%), but less common use of biologic monotherapy (risk difference -3.2%; 95% CI -6.2%, -0.1%) and no medications (risk difference -3.6%; 95% CI -6.6%, -0.6%).

Conclusions

Although patients with emergent/urgent resection may benefit from more aggressive postoperative therapy, there was evidence that emergent/urgent resection was more associated than elective resection with postoperative use of non-biologics for Crohn's disease. Future studies of treatment patterns and comparative effectiveness of postoperative treatment strategies for Crohn's patients should consider these differences between resection types, which may be important drivers of longer-term outcomes.

Axial Spondyloarthritis in Japan

PURPOSE OF REVIEW

The differences in the epidemiology and management of patients with axial spondyloarthritis (axSpA) among regions and countries largely depend on the positivity of human leukocyte antigen (HLA)-B27 and the health care system. This review article focused on axSpA in Japan, where the prevalence of HLA-B27 is extremely low (0.3%) and the universal health insurance system typically provides a 70% or more copayment by the government.

RECENT FINDINGS

A nationwide survey was conducted in Japan in 2018, which estimated that there were 3200 patients (95% confidence interval [CI]: 2400-3900) with ankylosing spondylitis (AS), a term interchangeable with radiographic axSpA (r-axSpA), and 800 patients (95% CI: 530-1100) had non-radiographic (nr)-axSpA. These data indicate a prevalence of 2.6/100,000 or 0.0026% for AS and 0.6/100,000 or 0.0006% for nr-axSpA. Patients with AS, but not those with nr-axSpA, are designated as suffering from intractable diseases in Japan; thus, their medical expenses are reduced by grant under the Act on Medical Care for Patients with Intractable Diseases. As of February 2022, infliximab, adalimumab, secukinumab, ixekizumab, and brodalumab have been approved for AS, and secukinumab, ixekizumab, and brodalumab have been approved for nr-axSpA. An algorithm for nr-axSpA in Japan has been developed for the proper diagnosis and use of these therapeutic agents. A low prevalence of axSpA, especially that of nr-axSpA, was found in Japan. Early referral and the resultant diagnosis and appropriate treatment of these patients by rheumatologists are crucial issues in Japan, as in other countries.

Differentiating nonradiographic axial spondyloarthritis from its mimics: a narrative review

Background

Optimal treatment of nonradiographic axial spondyloarthritis depends on accurate and timely diagnosis of the underlying disease; however, patients present with common symptoms that, in the absence of radiographic changes, may confound diagnosis.

Methods and findings

In this narrative review, a PubMed literature search was conducted through January 2021, with no date limits, to identify English-language publications discussing classification of nonradiographic axial spondyloarthritis, with an emphasis on clinical features and presentation, differential diagnoses, and mimics of disease. This review describes the epidemiology, clinical features, and burden of disease of nonradiographic axial spondyloarthritis as it relates to the overall axial spondyloarthritis spectrum and discusses mimics and differential diagnoses of nonradiographic axial spondyloarthritis that should be considered when evaluating patients with suspected nonradiographic axial spondyloarthritis in clinical practice.

Conclusions

Recognition of clinical features of nonradiographic axial spondyloarthritis, along with an understanding of comorbid conditions such as fibromyalgia, allows for differentiation from its mimics. Appropriate diagnosis of nonradiographic axial spondyloarthritis is important for aggressive management of disease to reduce pain, avoid loss of function, and improve quality of life.

Similarities and differences between non-radiographic and radiographic axial spondyloarthritis: The patient perspective from the Spanish atlas

AIM

Although non-radiographic axial spondyloarthritis (EspAax-nr) is well understood within health institutions, being considered along with radiographic EspAax (EspAax-r) as part of the same disease spectrum, patient understanding is unknown. The aim is to describe the patient's knowledge of the EspAax-nr entity.

METHODS

Atlas 2017, promoted by the Spanish Federation of Spondylarthritis Associations (CEADE), aims to comprehensively understand the reality of EspAax patients from a holistic approach. A cross-sectional on-line survey of unselected patients with self-reported EspAax diagnosis from Spain was conducted. Participants were asked to report their diagnosis. Socio-demographic, disease characteristics and patient-reported outcomes (PROs) were compared between those patients self-reporting as EspAax-nr and EspAax-r.

RESULTS

634 EspAax patients participated. Mean age 45.7±10.9 years, 50.9% female and 36.1% university-educated. 35 (5.2%) self-reported as EspAax-nr. Compared to EspAax-r patients, those with EspAax-nr were more frequently women (48.6% vs 91.4%, p<0.001), had longer diagnostic delay (10.1±8.9 vs 8.5±7.6 years), higher psychological distress (GHQ-12: 7.5±4.9 vs 5.6±4.4) and similar degree of disease activity (BASDAI: 5.7±2.1 vs 5.7±2.0), and unemployment rates (20.0% vs 21.6%). 20.0% of EspAax-nr received biologics vs 36.9% of EspAax-r, p=0.043. Visits to the rheumatologist in the past year were similar in both groups (3.8±4.5 vs 3.2±3.8), while GP visits were much higher within EspAax-nr (8.0±10.7 vs 4.9±13.3 p=0.003).

CONCLUSION

For the first time, EspAax-nr characteristics and PROs have been analyzed from the patient's perspective. Both groups reported similar trends with the exception of EspAax-nr being more frequently women, younger, having longer diagnostic delay and lower use of biologic therapy.

A Road Map of the Axial Spondyloarthritis Continuum

Axial spondyloarthritis (axSpA) is a chronic, immune-mediated inflammatory disease characterized by inflammatory low back pain, inflammation in peripheral joints and entheses, and other extra-articular or systemic manifestations. Although our understanding of the natural history of axSpA has been limited by incomplete knowledge of disease pathogenesis, axSpA is increasingly understood as a spectrum of axial, peripheral, and extra-articular inflammatory conditions that includes nonradiographic axSpA and radiographic axSpA, also known as ankylosing spondylitis. In this narrative review, we present a road map of this axSpA continuum, highlighting genetic risk factors for the development of axSpA, triggers of disease, and reasons for and implications of diagnostic delay. We present a detailed overview of the spectrum of axSpA clinical manifestations and highlight factors known to influence the risk of disease progression. Finally, we provide some expert commentary on the practical use of this road map to assist health care providers in the identification of axSpA in clinical practice.

Geographic Variations in Diagnosis and Treatment of Ankylosing Spondylitis in the United States: A Real-World Study

Introduction

Diagnosis difficulties are common for ankylosing spondylitis (AS) patients, leading to inadequate and inconsistent treatment. We evaluated the national and geographic variability in disease diagnosis and treatment in the United States.

Methods

This retrospective, cross-sectional analysis utilized the IBM® MarketScan® Administrative Claims Database from 2014 to 2019. AS patients ≥ 18 years of age with continuous medical and pharmacy enrollment during the calendar year and complete geographic information during the study period were included. Patient cohorts assessed were D1 (≥ 1 AS diagnoses within each calendar year of assessment between 2014 and 2019), D2 (≥ 2 non-rheumatologist AS diagnoses), and D3 (≥ 2 rheumatologist AS diagnoses). For D2 and D3, diagnoses were ≥ 6 months apart, but within 18 months. Annual AS diagnostic prevalence and treatment rates were determined from 2014 to 2019 nationally and per state in 2019. Treatments assessed were disease-modifying antirheumatic drugs (DMARDs), opioids, nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and methotrexate.

Results

Nationally, AS diagnostic prevalence increased from 2014 to 2019, with 2019 rates of 9.6 (D1), 5.1 (D2), and 3.5 (D3) per 10,000 persons. Diagnostic prevalence varied between states, which was not explained by age, sex, racial distribution, or rheumatologists per capita. Nationally, a greater percentage of D3 patients vs. D1 and D2 patients received biologic/targeted synthetic DMARDs (bDMARD/tsDMARDs) and conventional synthetic DMARD. Opioid use ranged from 37 to 40% in 2019 and decreased from 2014 for all cohorts. Corticosteroid and methotrexate use decreased slightly, while NSAID and bDMARD/tsDMARD use generally increased from 2014 to 2019.

Conclusions

AS diagnostic prevalence is increasing nationally, though it remains low among some states. bDMARD/tsDMARDs use was more common among patients treated by rheumatologists. Opioid and corticosteroid use is decreasing, though national rates remain high with significant state variability. Further education is needed, particularly in states with low prevalence and inadequate treatment, to improve diagnosis and treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00406-9.

Gender Differences in Ankylosing Spondylitis Patients with Advanced Hip Involvement: Results from A Matched Retrospective Cohort Study

Objective

To determine the gender differences in ankylosing spondylitis (AS) patients with advanced hip involvement.

Methods

We retrospectively analyzed the 373 consecutive AS patients with advanced hip involvement from 2012 to 2017 and divided them into two groups by sex with 340 men and 33 women. Research data on hip involvement in the patients were obtained from medical records and radiographs. The severity of radiographic hip involvement was evaluated by the Bath Ankylosing Spondylitis Radiology Hip Index (BASRI‐hip) scoring system. The data on clinical characteristics, radiographic hip involvement, and laboratory values were compared between the two groups. The comparison was performed again between the two groups after adjusting for the onset age and disease duration by propensity score matching (PSM).

Results

Men underwent total hip arthroplasty earlier than women in the patients, with a median age of 31 years (range, 19–67 years) vs 36 years (range, 23–67 years), respectively (P < 0.05). Hip involvement was found to be younger in men than that in women, with a median age of 18 years (range, 7–56 years) vs 23 years (range, 5–55 years) (P < 0.05), and men with bilateral onset in hips had a higher frequency than women with that (66.2% vs 39.4%) (P < 0.05). There was no gender difference in the proportion of bilateral advanced hip involvement (85.3% vs 72.7%) (P > 0.05). The proportion of the patients who had spinal involvement (89.1% vs 69.7%), flexion contracture in the hip (43.8% vs 24.2%), hip range of motion =0° (53.5% vs 30.3%), and an elevated level of C‐reactive protein (CRP) (69.1% vs 51.5%) was significantly higher in men than that in women (P < 0.05). After adjusting for the onset age and disease duration by PSM (1:1), men with bilateral onset in hips still had a higher frequency than women with that (76.7% vs 40.0%), and the proportion of the patients who had spinal involvement (90.0% vs 66.7%) and an elevated level of CRP (80.0% vs 53.3%) was significantly higher in men than that in women (P < 0.05).

Conclusions

The disease pattern of hip involvement in AS has gender differences, with bilateral onset being the dominant pattern in men and unilateral onset being more common in women. However, the frequency of bilateral advanced hip involvement has no gender difference eventually. The higher prevalence of spinal involvement in men with AS may be responsible for the more severe functional impairment compared with women.

Clinical Manifestations and Diagnosis of Axial Spondyloarthritis

BACKGROUND

Axial spondyloarthritis (axSpA) is a chronic, rheumatic disease characterized by inflammation of the sacroiliac joint, spine, and entheses. Axial spondyloarthritis affects up to 1.4% of adults in the United States and is associated with decreased quality of life, increased mortality, and substantial health care-related costs, imposing a high burden on patients, their caregivers, and society.

SUMMARY OF WORK

Diagnosing axSpA can be difficult. In this review, we seek to help rheumatologists in recognizing and diagnosing axSpA.

MAJOR CONCLUSIONS

A discussion of challenges associated with diagnosis is presented, including use and interpretation of imaging, reasons for diagnostic delays, differences in disease presentation by sex, and differential diagnoses of axSpA.

FUTURE RESEARCH DIRECTIONS

The early diagnosis of axSpA and advances in available therapeutic options have improved patient care and disease management, but delays in diagnosis and treatment remain common. Additional research and education are critical for recognizing diverse axSpA presentations and optimizing management early in the course of disease.

Significance of structural changes in the sacroiliac joints of patients with axial spondyloarthritis detected by MRI related to patients symptoms and functioning

Axial spondyloarthritis (axSpA) is a chronic inflammatory rheumatic disease that manifests primarily in the axial skeleton, initially mostly in the sacroiliac joints (SIJ), usually later spreading to the spine. The disease is characterised by inflammation and new bone formation which are mainly assessed by conventional radiography (CR) and magnetic resonance imaging (MRI). Tumour necrosis factor inhibitors (TNFi) and interleukin-17 antagonists have been shown to be efficacious and efficient in patients with axSpA. This treatment seems to also inhibit structural damage, for example, retard radiographic progression. Indeed, a reduction of new bone formation in the spine, as assessed by CR, has been reported to occur after at least 2 years of therapy with TNFi. Recently, a reduction of erosions and ankylosis in the SIJ has also been observed in axSpA patients treated with etanercept and filgotinib. In this narrative review, we discuss the limited significance of such findings.

Classification Criteria in Axial Spondyloarthritis: What Have We Learned; Where Are We Going?

Spondyloarthritis (SpA) is a chronic inflammatory condition that can have a predominately peripheral or axial presentation. Axial SpA (axSpA) affects the axial skeleton with either radiographic (r-axSpA) or nonradiographic (nr-axSpA) changes. Radiographic changes are a late disease feature and earlier disease stages can be identified by incorporating other imaging methods. The diagnosis of axSpA is a clinical diagnosis and classification criteria are not aimed to be diagnostic tools. The split between r-axSpA and nr-axSpA is artificial and we should move toward the unifying concept of axSpA. Our understanding of genetics, biomarkers, and immunopathophenotypes will drive further refinement of classification criteria.

Monocyte transcriptomes from patients with axial spondyloarthritis reveal dysregulated monocytopoiesis and a distinct inflammatory imprint

BACKGROUND

In patients with axial spondyloarthritis (axSpA), monocytes show a pre-activated phenotype. Gut inflammation is a trigger of monocyte activation and may also affect their development in the bone marrow (BM). As gut inflammation is commonly observed in axSpA patients, we performed a detailed analysis of monocyte transcriptomes of axSpA patients in two cohorts and searched for signs of activation and developmental adaptations as putative imprints of gut inflammation.

METHODS

Transcriptomes of blood CD14+ monocytes of HLA-B27+ axSpA patients and healthy controls (HC) were generated by microarrays from cohort 1 and by RNA-sequencing from cohort 2. Differentially expressed genes from both analyses were subjected to gene set enrichment analysis (GSEA) and to co-expression analysis in reference transcriptomes from BM cells, blood cells and activated monocytes. As serological markers of translocation, 1,3 beta-glycan, intestinal fatty acid binding protein, and lipopolysaccharide binding protein (LBP) were determined by LAL and ELISA.

RESULTS

Transcriptome analysis identified axSpA-specific monocyte signatures showing an imprint of LPS/cytokine-activated monocytes, late granulopoietic BM cells, blood neutrophils, and G-CSF-mobilized blood cells, which suggests LPS/TNF activation and more prominent BM adaptation promoting a neutrophil-like phenotype. GSEA mapped axSpA upregulated genes to inflammatory responses and TNFα signaling and downregulated probe-sets to metabolic pathways. Among translocation markers, LBP levels were significantly increased in axSpA patients vs. HC (p < 0.001). Stratified analysis by disease activity and stage identified an "active disease signature" (BASDAI ≥ 4) with an imprint of LPS/cytokine-activated monocytes and CD16+ monocyte subsets. The "AS signature" (vs. non-radiographic axSpA) showed a reinforced neutrophil-like phenotype due to deprivation of dendritic cell transcripts.

CONCLUSIONS

The neutrophil-like phenotype of axSpA monocytes points towards a biased monocytopoiesis from granulocyte-monocyte progenitors. This shift in monocytopoiesis and the LPS/cytokine imprint as well as the elevated LBP levels are indicators of systemic inflammation, which may result from bacterial translocation. The BM adaptation is most prominent in AS patients while disease activity appears to be linked to activation and trafficking of monocytes.

Secukinumab in non-radiographic axial spondyloarthritis: subgroup analysis based on key baseline characteristics from a randomized phase III study, PREVENT

BACKGROUND

To investigate the efficacy of secukinumab in patients with active non-radiographic axial spondyloarthritis (nr-axSpA) grouped by disease activity as assessed by C-reactive protein (CRP) levels and/or magnetic resonance imaging (MRI) scores, human leukocyte antigen (HLA)-B27 status, and sex.

METHODS

The phase III PREVENT study randomized (1:1:1) 555 patients to receive subcutaneous secukinumab 150 mg with (LD) or without (NL) loading dose or placebo weekly, followed by every 4 weeks starting at week 4. Here, we report the results of a post hoc analysis reporting the efficacy outcomes (pooled secukinumab) to 16 weeks by CRP, MRI, HLA-B27, and sex.

RESULTS

Efficacy differences between the secukinumab and the placebo groups were highest in the CRP+, MRI+, HLA-B27+, and male subgroups, particularly for Ankylosing Spondylitis Disease Activity Score-CRP inactive disease and Assessment of SpondyloArthritis international Society (ASAS) partial remission outcomes. ASAS40 response rates in the CRP+/MRI+ subgroup was 52.3% (secukinumab) versus 21.8% (placebo; P < 0.0001) at week 16. ASAS40 response rates (secukinumab versus placebo) were 43.9% versus 32.6% in HLA-B27+, 32.7% versus 16.4% in HLA-B27- subgroups, 51.2% versus 30.8% in male, and 31.7% versus 25.3% in female patients, respectively.

CONCLUSIONS

Secukinumab improved the signs and symptoms of nr-axSpA across patients grouped by CRP (+/-) and/or MRI (+/-) status, HLA-B27 (+/-) status, and sex. The highest treatment differences between secukinumab and placebo were observed in patients with both elevated CRP and evidence of sacroiliitis on MRI. Treatment difference was minimal between HLA-B27 (+) and (-) subgroups. Male patients had higher relative responses than female patients.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT02696031 . Registered on 02 March 2016.

Method for Diagnosing the Bone Marrow Edema of Sacroiliac Joint in Patients with Axial Spondyloarthritis Using Magnetic Resonance Image Analysis Based on Deep Learning

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease of the sacroiliac joints. In this study, we develop a method for detecting bone marrow edema by magnetic resonance (MR) imaging of the sacroiliac joints and a deep-learning network. A total of 815 MR images of the sacroiliac joints were obtained from 60 patients diagnosed with axSpA and 19 healthy subjects. Gadolinium-enhanced fat-suppressed T1-weighted oblique coronal images were used for deep learning. Active sacroiliitis was defined as bone marrow edema, and the following processes were performed: setting the region of interest (ROI) and normalizing it to a size suitable for input to a deep-learning network, determining bone marrow edema using a convolutional-neural-network-based deep-learning network for individual MR images, and determining sacroiliac arthritis in subject examinations based on the classification results of individual MR images. About 70% of the patients and normal subjects were randomly selected for the training dataset, and the remaining 30% formed the test dataset. This process was repeated five times to calculate the average classification rate of the five-fold sets. The gradient-weighted class activation mapping method was used to validate the classification results. In the performance analysis of the ResNet18-based classification network for individual MR images, use of the ROI showed excellent detection performance of bone marrow edema with 93.55 ± 2.19% accuracy, 92.87 ± 1.27% recall, and 94.69 ± 3.03% precision. The overall performance was additionally improved using a median filter to reflect the context information. Finally, active sacroiliitis was diagnosed in individual subjects with 96.06 ± 2.83% accuracy, 100% recall, and 94.84 ± 3.73% precision. This is a pilot study to diagnose bone marrow edema by deep learning based on MR images, and the results suggest that MR analysis using deep learning can be a useful complementary means for clinicians to diagnose bone marrow edema.

The Salivary Microbiota, Cytokines, and Metabolome in Patients with Ankylosing Spondylitis Are Altered and More Proinflammatory than Those in Healthy Controls

The pathogenesis of ankylosing spondylitis (AS) remains unclear but appears to be associated with heredity and the environment. The mouth links the external environment to the gut and lungs. In the present study, compared to that observed in healthy controls (HCs), AS saliva was depleted of Bacilli such as Streptococcus, enriched with Clostridia such as Veillonellaceae, and enriched with opportunistic pathogens from Proteobacteria such as Brucella spp. and Campylobacter concisus. AS saliva was enriched with 16 cytokines related to inflammation, such as soluble IL-6 receptor α (sIL-6Rα), interleukin 2 (IL-2), IL-10, IL-11, IL-12p40, IL-12p70, IL-20, IL-26, IL-27, IL-28A, IL-29, alpha 2 interferon (IFN-α2), IFN-β, and matrix metalloproteinase 3 (MMP-3). AS saliva was also enriched with hazardous compounds, such as cadaverine and putrescine. AS-altered salivary bacteria, compounds, and cytokines are closely linked with disease indicators. Oral cleaning reduced the levels of proinflammatory cytokines and hazardous compounds in AS saliva compared with HC saliva. AS saliva induced the production of more proinflammatory cytokines, such as IL-12p70 and IL-8, by THP-1 monocyte-derived macrophages, than did HC saliva. The results highlight the importance of salivary microbes, cytokines, and compounds in the development and treatment of AS and provide new ideas for the pathogenesis and treatment of AS.

IMPORTANCE Ankylosing spondylitis (AS) affects as much as 0.32% of the population in some districts and causes work disability in one-third of these patients. Microbes are considered to play important roles in AS pathogenesis, and the mouth links the environment to the lungs and the gut. Our results showed that opportunistic pathogens such as Brucella and Campylobacter are enriched in the saliva of AS patients with ankylosing spondylitis. In addition, proinflammatory cytokines and hazardous materials such as putrescine were also enriched in the saliva of AS patients.[AQ1 sentence edit] Interestingly, the opportunistic pathogens and hazardous materials detected in the saliva of AS patients were associated with disease indexes. The saliva of AS patients was shown to induce immune cells to secrete proinflammatory cytokines in vitro. Reducing the levels of salivary microbes can significantly reduce the hazardous materials present in the saliva of AS patients. Our results provide a new perspective on the potential role of salivary microbes, cytokines, and hazardous compounds in the pathogenesis and treatment of AS.

Comparison of Men and Women With Axial Spondyloarthritis in the US-Based Corrona Psoriatic Arthritis/Spondyloarthritis Registry

OBJECTIVE

To compare patient characteristics and disease burden between men and women with axial spondyloarthritis (axSpA) in the US-based Corrona Psoriatic Arthritis/Spondyloarthritis (PsA/SpA) Registry.

METHODS

Patients aged ≥ 18 years with axSpA enrolled in the Corrona PsA/SpA Registry between March 2013 and November 2018 who were not concurrently diagnosed with PsA were included. Patient demographics, clinical characteristics, disease activity, patient-reported symptoms, work productivity, and treatment history at enrollment were compared between men and women, using t tests or Wilcoxon rank-sum tests for continuous variables and chi-square or Fisher exact tests for categorical variables.

RESULTS

Of 498 patients with axSpA and available sex information, 307 (61.6%) were men and 191 (38.4%) were women. Compared with men, women had higher disease activity as measured by Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and physician global assessment, and had higher tender/swollen joint counts and enthesitis scores (all P ≤ 0.01). Women also had worse patient-reported symptoms (pain, fatigue, Health Assessment Questionnaire for the Spondyloarthropathies, and EuroQol visual analogue scale; all P < 0.05), had greater work and activity impairment, and were less likely to work full time than men. Prior conventional synthetic disease-modifying antirheumatic drug and prednisone use was more common in women than in men (both P < 0.05). Additionally, women were more likely to have diagnoses of depression and fibromyalgia (both P < 0.01).

CONCLUSION

In this US registry of patients with axSpA, women had higher overall disease burden and more peripheral manifestations than men. Improved awareness of sex differences in the presentation of axSpA may aid physicians in earlier identification and improved disease management.

Comparing symptoms, treatment patterns, and quality of life of ankylosing spondylitis and non-radiographic axial spondyloarthritis patients in the USA: findings from a patient and rheumatologist Survey

Objectives

The aim of this study was to compare the symptoms, treatment patterns, and quality of life (QoL) of ankylosing spondylitis (AS) patients to non-radiographic axial spondyloarthritis (nr-axSpA) patients in the USA.

Method

A cross-sectional survey was conducted with rheumatologists and their consulting patients in the USA from June through August 2018. Patients who had a rheumatologist confirmed diagnosis of AS and nr-axSpA were eligible to participate. Patient demographics, symptoms, and medication use were reported by the rheumatologist, while work disability and QoL measures were reported by the patient. Patient demographics, symptoms, QoL and treatment patterns of AS and nr-axSpA patients were compared using parametric tests and non-parametric tests when appropriate.

Results

A total of 515 AS patients and 495 nr-axSpA patients were included in this analysis. A higher proportion of AS patients were male (p < 0.001), older (p = 0.014), and more likely to be prescribed a biologic (p < 0.0001). On average, AS patients experienced slightly more symptoms at diagnosis (p = 0.023); however, nr-axSpA patients were more likely to experience enthesitis (p = 0.048) and synovitis (p = 0.003). Patient reported outcomes such as the ASAS Health Index (p = 0.171), ASQoL (p = 0.296), BASDAI (p = 0.124), and WPAI (p = 0.183) were similar between AS and nr-axSpA patients after adjusting for confounding variables such as medication use.

Conclusions

AS and nr-axSpA patients share the same clinical features. The burden of the disease, as assessed by QoL measurements, is also similar in AS and nr-axSpA patients; however, despite these similarities, patients with nr-axSpA are less likely to be treated with a biologic.

Key Points

• Ankylosing spondylitis and non • radiographic axial spondyloarthritis patients share similar clinical features and burden of disease. • Quality of life is similar among ankylosing spondylitis and non • radiographic axial spondyloarthritis after adjusting for current treatment patterns.

The role of ixekizumab in non-radiographic axial spondyloarthritis

Among patients with axial spondyloarthritis (axSpA), non-radiographic axial spondyloarthritis (nr-axSpA) is distinguished from ankylosing spondylitis (AS) by a lack of obvious radiographic changes in the sacroiliac joint. Tumor necrosis factor inhibitor (TNFi) has been used as a highly effective treatment in patients with AS and has shown good efficacy and safety in clinical trials in patients with nr-axSpA. As the pathophysiological mechanism for axSpA has started to become better recognized, various drugs other than TNFi, all of which are related to the interleukin-17 (IL-17) axis, are being evaluated in patients with axSpA. IL-17 inhibitors, such as secukinumab and ixekizumab, are effective drugs for patients with AS. A recent clinical trial reported that ixekizumab, a monoclonal antibody against IL-17A, was also effective in patients with nr-axSpA. In a COAST-X study, ixekizumab was superior to a placebo for improving signs and symptoms in patients with nr-axSpA at weeks 16 and 52. The adverse events were no different from those found in previous ixekizumab studies, and no new safety signals were identified. However, when considering several IL-17 inhibitors, it is necessary to obtain sufficient data to identify the exacerbation of extra-articular manifestation. In terms of effectiveness and safety, ixekizumab may be an appropriate alternative to TNFi in nr-axSpA patients.

Effectiveness and safety of 12-month certolizumab pegol treatment for axial spondyloarthritis in real-world clinical practice in Europe

Objectives

The efficacy and safety of certolizumab pegol (CZP), an Fc-free, PEGylated anti-TNF, in axial spondyloarthritis (axSpA) has been established in clinical trial settings. We report CZP effectiveness and safety in European clinical practice in patients with axSpA, including radiographic (r-) and non-radiographic (nr-) axSpA.

Methods

CIMAX (NCT02354105), a European non-interventional multicentre prospective study, observed CZP treatment response and safety over 12 months in a real-world axSpA cohort. The primary outcome was change from baseline in BASDAI to week 52, with additional outcomes pertaining to effectiveness and safety. Patients who received ≥1 dose CZP were followed up for adverse events, and those with baseline and ≥1 post-baseline BASDAI assessment were included in effectiveness analyses.

Results

A total of 672 patients (r-axSpA: 469; nr-axSpA: 201; unconfirmed diagnosis: 2) from 101 sites received ≥1 dose of CZP, of whom 564 (r-axSpA: 384; nr-axSpA: 179; unconfirmed: 1) were included in the effectiveness analyses. The mean baseline BASDAI was 6.1 in the overall axSpA population and r-axSpA and nr-axSpA subpopulations. At week 52, the mean (s.d.) change in BASDAI was −2.9 (2.3; n = 439); for r-axSpA and nr-axSpA, it was −2.9 (2.2; n = 301) and −2.8 (2.4; n = 137), respectively (P <0.0001 for all). Similar improvements were seen across other axSpA disease measures. In total, 37.9% (255/672) patients experienced adverse events, and 1.8% (12/672) experienced ≥1 serious adverse events.

Conclusion

Improvements observed in signs and symptoms of axSpA following one year of CZP treatment in real-world clinical practice were similar to those from previous randomized clinical trials, with no new safety concerns.

Chronic Pain and Assessment of Pain Sensitivity in Patients With Axial Spondyloarthritis: Results From the SPARTAKUS Cohort

OBJECTIVE

To study differences in pain reports between patients with ankylosing spondylitis (AS) and nonradiographic axial spondyloarthritis (nr-axSpA), and to assess how pain sensitivity measures associate with disease and health outcomes.

METHODS

Consecutive patients with axial SpA (axSpA) were enrolled in the population-based SPARTAKUS cohort (2015-2017) and classified as AS (n = 120) or nr-axSpA (n = 55). Pain was assessed with questionnaires (intensity/duration/distribution) and computerized cuff pressure algometry to measure pain sensitivity (pain threshold/pain tolerance/temporal summation of pain). Linear regression models were used to compare pain measures between patients with AS and nr-axSpA, and to assess associations between pain sensitivity measures and disease and health outcomes.

RESULTS

Of 175 patients with axSpA, 43% reported chronic widespread pain, with no significant differences in any questionnaire-derived or algometry-assessed pain measures between patients with AS and nr-axSpA. Lower pain tolerance was associated with longer symptom duration, worse Ankylosing Spondylitis Disease Activity Score using C-reactive protein (ASDAS-CRP), Bath Ankylosing Spondylitis Functional Index, and Bath Ankylosing Spondylitis Metrology Index (BASMI), more pain regions, unacceptable pain, worse Maastricht AS Enthesitis Score (MASES), fatigue, anxiety, and health-related quality of life. Further, lower pain threshold was associated with worse ASDAS-CRP and MASES, whereas higher temporal summation was associated with longer symptom duration, unacceptable pain, and worse BASMI.

CONCLUSION

Chronic pain is common in axSpA, with no observed differences in any pain measures between patients with AS and nr-axSpA. Further, higher pain sensitivity is associated with having worse disease and health outcomes. The results indicate that patients with AS and nr-axSpA, in line with most clinical characteristics, have a similar pain burden, and they highlight large unmet needs regarding individualized pain management, regardless of axSpA subgroup.

Similarities and differences between non-radiographic and radiographic axial spondyloarthritis: The patient perspective from the Spanish atlas

AIM

Although non-radiographic axial spondyloarthritis (EspAax-nr) is well understood within health institutions, being considered along with radiographic EspAax (EspAax-r) as part of the same disease spectrum, patient understanding is unknown. The aim is to describe the patient's knowledge of the EspAax-nr entity.

METHODS

Atlas 2017, promoted by the Spanish Federation of Spondylarthritis Associations (CEADE), aims to comprehensively understand the reality of EspAax patients from a holistic approach. A cross-sectional on-line survey of unselected patients with self-reported EspAax diagnosis from Spain was conducted. Participants were asked to report their diagnosis. Socio-demographic, disease characteristics and patient-reported outcomes (PROs) were compared between those patients self-reporting as EspAax-nr and EspAax-r.

RESULTS

634 EspAax patients participated. Mean age 45.7±10.9 years, 50.9% female and 36.1% university-educated. 35 (5.2%) self-reported as EspAax-nr. Compared to EspAax-r patients, those with EspAax-nr were more frequently women (48.6% vs 91.4%, p<0.001), had longer diagnostic delay (10.1±8.9 vs 8.5±7.6 years), higher psychological distress (GHQ-12: 7.5±4.9 vs 5.6±4.4) and similar degree of disease activity (BASDAI: 5.7±2.1 vs 5.7±2.0), and unemployment rates (20.0% vs 21.6%). 20.0% of EspAax-nr received biologics vs 36.9% of EspAax-r, p=0.043. Visits to the rheumatologist in the past year were similar in both groups (3.8±4.5 vs 3.2±3.8), while GP visits were much higher within EspAax-nr (8.0±10.7 vs 4.9±13.3 p=0.003).

CONCLUSION

For the first time, EspAax-nr characteristics and PROs have been analyzed from the patient's perspective. Both groups reported similar trends with the exception of EspAax-nr being more frequently women, younger, having longer diagnostic delay and lower use of biologic therapy.

Improvement of Signs and Symptoms of Nonradiographic Axial Spondyloarthritis in Patients Treated With Secukinumab: Primary Results of a Randomized, Placebo-Controlled Phase III Study

Objective

To report the primary (1‐year) results from PREVENT, the first phase III study evaluating secukinumab in patients with active nonradiographic axial spondyloarthritis (SpA).

Methods

A total of 555 patients were randomized (1:1:1) to receive subcutaneous secukinumab 150 mg with a loading dose (loading dose [LD] group), secukinumab 150 mg without a loading dose (non–loading dose [NL] group), or placebo weekly and then every 4 weeks starting at week 4. The NL group received placebo at weeks 1, 2, and 3 to maintain blinding. Switch to open‐label secukinumab or standard of care was permitted after week 20. The study had 2 independent analysis plans, per European Union and non‐US (plan A; week 16) and US (plan B; week 52) regulatory requirements. The primary end point was 40% improvement in disease activity according to the Assessment of SpondyloArthritis international Society (ASAS40) criteria at week 16 (in the LD group) and at week 52 (in the NL group) in tumor necrosis factor inhibitor (TNFi)–naive patients. Safety analyses included all patients who received ≥1 dose of study treatment.

Results

Overall, 481 patients completed 52 weeks of treatment, including 84.3% (156 of 185) in the LD group, 89.7% (165 of 184) in the NL group, and 86.0% (160 of 186) in the placebo group. The proportion of patients who switched to open‐label or standard of care between weeks 20 and 48 was 50.8% in the LD group, 47.3% in the NL group, and 64.0% in the placebo group. Both primary and all secondary end points were met at week 16. The proportion of TNFi‐naive patients who met ASAS40 was significantly higher for LD at week 16 (41.5%) and NL at week 52 (39.8%) versus placebo (29.2% at week 16 and 19.9% at week 52; both P < 0.05). No new safety findings were reported.

Conclusion

Our findings indicate that secukinumab 150 mg provides significant and sustained improvement in signs and symptoms of nonradiographic axial SpA through 52 weeks. Safety was consistent with previous reports.

Physical Activity and Attitudes Toward Exercise in People With Axial and Peripheral Spondyloarthritis

OBJECTIVE

To evaluate physical activity and attitudes toward exercise among people with axial (ax-) and peripheral (p-) spondyloarthritis (SpA).

METHODS

Using baseline information from an ongoing, longitudinal, prospective SpA cohort study (n = 264), self-reported attitudes and beliefs toward exercise were assessed using questionnaires. Total metabolic equivalent (MET) hours of self-reported physical activity per week, time spent in activities, and activity levels were calculated from the Nurses' Health Study Physical Activity Questionnaire II (NHSPAQ II). Adjusted multivariable linear models estimated the relationship between physical activity and disease status (axial vs peripheral).

RESULTS

Regardless of predominant anatomic distribution of disease, most participants were well-educated, non-Hispanic White men. Approximately 40% met the US Department of Health and Human Services physical activity recommendations. Positive attitudes, beliefs, and perceived benefits toward exercise were similar by anatomic distribution of disease. Despite similar MET h/week, participants with axial disease had greater concerns regarding discomfort and joint injuries than those with peripheral disease. Compared to those with pSpA (n = 201), participants with axSpA (n = 63) spent less time engaging in light and moderate activities (adjusted β in light activity: -1.94 min/week, 95% CI -2.96 to -0.93; adjusted β in moderate activity: -1.05 min/week, 95% CI -2.12 to 0.02).

CONCLUSION

Participants with axSpA had greater concerns regarding discomfort and injuries from exercise than those with pSpA. Although no differences in time spent in vigorous activities were observed, participants with axSpA spent less time than those with pSpA in light to moderate activities.

Non-radiographic axial spondyloarthritis

Non-radiographic axial spondyloarthritis (nr-axSpA) is a subgroup of axial spondyloarthritis (axSpA) without fulfilling the modified New York criteria of sacroiliac joint radiographs for ankylosing spondylitis (AS). AS and nr-axSpA share various demographic and clinical features and disease burden, although sex and objective inflammatory findings such as elevated serum C-reactive protein level are slightly different between AS and nr-axSpA. Recently, diagnostic guidance for nr-axSpA in Japan was proposed for epidemiological studies of a population with a low prevalence of HLA-B27 positivity and the use of molecular targeted agents suitable for the unique medical care system in Japan. A biological agent targeting interleukin-17 was approved for nr-axSpA by the Pharmaceutical and Medical Devices Agency (PMDA) in August 2020. Some other biological agents will be also available for Japanese patients with nr-axSpA in the near future.

Semaphorin 4D Induces an Imbalance of Th17/Treg Cells by Activating the Aryl Hydrocarbon Receptor in Ankylosing Spondylitis

Objectives

Semaphorin 4D (Sema4D) is constitutively expressed on T cells and osteoclasts, and regulates T cell proliferation and bone remodeling. In addition, several studies have shown that Sema4D is involved in the pathogenesis of autoimmunity. We undertook this study to investigate the mechanism by which Sema4D affects the pathogenic progress of ankylosing spondylitis (AS).

Methods

Soluble Sema4D (sSema4D) levels in serum were analyzed by enzyme-linked immunosorbent assay. The cell surface levels and transcripts of Sema4D were evaluated in CD4 + and CD19 + cells from the AS patients and healthy individuals. The mRNA expression levels were assessed by quantitative polymerase chain reaction (qPCR). The proportions of Treg cells and IL-17-producing T-cells (Th17 cells) differentiated from CD4 + T cells were analyzed by flow cytometric analysis. The aryl hydrocarbon receptor (AhR) agonistic effect of Sema4D was detected by analyzing the activation of downstream signaling pathways and target genes using Luciferase and EROD assay.

Results

Levels of sSema4D were elevated in both serum from AS patients, and clinical features markers were correlated with serum sSema4D levels. Sema4D facilitated CD4 + T cells proliferation and Th17 cells differentiation and inhibited Treg cells differentiation by enhancing RORγt expression and reducing Foxp3 expression, with increasing expression and secretion of IL-17 and IL-22. It induced the expression and activity of AhR target gene CYP1A1 and XRE reporter activity via interaction with CD72.

Conclusion

These findings indicate that Sema4D as a potent activator of T cells in the immune response contributes to the inflammation of AS by inducing imbalance in Th17 and Treg cell populations in an AhR-dependent manner, suggesting it is a crucial participant in AS pathogenesis.