Goodbye to the term 'ankylosing spondylitis', hello 'axial spondyloarthritis': time to embrace the ASAS-defined nomenclature

Ankylosing spondylitis (AS) is the historic term used for decades for the HLA-B27-associated inflammatory disease affecting mainly the sacroiliac joints (SIJ) and spine. Classification criteria for AS have radiographic sacroiliitis as a dominant characteristic. However, with the availability of MRI of SIJ, it could be demonstrated that the disease starts long before definite SIJ changes become visible on radiographs. The Assessment of SpondyloArthritis international Society, representing a worldwide group of experts reached consensus on changes in the nomenclature pertaining to axial spondyloarthritis (axSpA), such as the terminology of diagnosis and of assessment of disease activity tools. These are important changes in the field, as experts in axSpA are now in agreement that the term axSpA is the overall term for the disease. A further differentiation, of which radiographic versus non-radiographic is only one aspect, may be relevant for research purposes. Another important decision was that the terms AS and radiographic axSpA (r-axSpA) can be used interchangeably, but that the preferred term is r-axSpA. Based on the decision that axSpA is the correct terminology, a proposal was made to officially change the meaning of the ASDAS acronym to 'Axial Spondyloarthritis Disease Activity Score'. In addition, for simplification it was proposed that the term ASDAS (instead of ASDAS-CRP) should be preferred and applied to the ASDAS calculated with C reactive protein (CRP). It is hoped that these changes will be used consequently for education, in textbooks, manuscripts and presentations.

Radiographic Progression in Sacroiliac Joints in Patients With Axial Spondyloarthritis: Results From a Five-Year International Observational Study

OBJECTIVE

To evaluate progression from nonradiographic (nr-) to radiographic axial spondyloarthritis (r-axSpA) over 5 years in patients with recently diagnosed (≤1 year) axSpA fulfilling the Assessment of SpondyloArthritis international Society (ASAS) classification criteria.

METHODS

A prospsective, observational study (Patients with Axial Spondyloarthritis: Multi-Country Registry of Clinical Characteristics) was conducted in rheumatology practices in 29 countries. Baseline and follow-up radiographs of sacroiliac joints were centrally evaluated by three readers according to the grading system of the modified New York criteria for patients initially classified as nr-axSpA. Radiographic progression from nr-axSpA to r-axSpA was evaluated by Kaplan-Meier analysis. Cox proportional regression analyses for progression from nr-axSpA to r-axSpA were also conducted.

RESULTS

Among 2,165 patients with axSpA, 1,612 (74%) were classified as having r-axSpA (1,050 [65%]) or nr-axSpA (562 [35%]) by central reading. Of 246 patients with nr-axSpA (mean [SD] symptom duration: 4.4 [6.2] years) who had at least one follow-up sacroiliac joint radiograph, progression from nr-axSpA to r-axSpA at any follow-up visit was observed in 40 patients (16%) over 5 years. Mean time to radiographic progression was 2.4 years (ranging from 0.9 to 5.1 years). Progression to r-axSpA was associated with male sex (hazard ratio [HR] 3.16 [95% CI 1.22-8.17]), fulfillment of the imaging arm of the ASAS classification criteria (HR 6.64 [1.37-32.25]), and good response to nonsteroidal anti-inflammatory drugs (HR 4.66 [1.23-17.71]).

CONCLUSION

16% of patients with nr-axSpA progressed to r-axSpA within 5 years. Male sex, fulfillment of the imaging arm of the ASAS criteria, and good response to nonsteroidal anti-inflammatory drugs were predictors of radiographic progression in patients with recently diagnosed axSpA.

Proteomic and genomic profiling of plasma exosomes from patients with ankylosing spondylitis

INTRODUCTION

Recent advances in understanding the biology of ankylosing spondylitis (AS) using innovative genomic and proteomic approaches offer the opportunity to address current challenges in AS diagnosis and management. Altered expression of genes, microRNAs (miRNAs) or proteins may contribute to immune dysregulation and may play a significant role in the onset and persistence of inflammation in AS. The ability of exosomes to transport miRNAs across cells and alter the phenotype of recipient cells has implicated exosomes in perpetuating inflammation in AS. This study reports the first proteomic and miRNA profiling of plasma-derived exosomes in AS using comprehensive computational biology analysis.

METHODS

Plasma samples from patients with AS and healthy controls (HC) were isolated via ultracentrifugation and subjected to extracellular vesicle flow cytometry analysis to characterise exosome surface markers by a multiplex immunocapture assay. Cytokine profiling of plasma-derived exosomes and cell culture supernatants was performed. Next-generation sequencing was used to identify miRNA populations in exosomes enriched from plasma fractions. CD4+ T cells were sorted, and the frequency and proliferation of CD4+ T-cell subsets were analysed after treatment with AS-exosomes using flow cytometry.

RESULTS

The expression of exosome marker proteins CD63 and CD81 was elevated in the patients with AS compared with HC (q<0.05). Cytokine profiling in plasma-derived AS-exosomes demonstrated downregulation of interleukin (IL)-8 and IL-10 (q<0.05). AS-exosomes cocultured with HC CD4+ T cells induced significant upregulation of IFNα2 and IL-33 (q<0.05). Exosomes from patients with AS inhibited the proliferation of regulatory T cells (Treg), suggesting a mechanism for chronically activated T cells in this disease. Culture of CD4+ T cells from healthy individuals in the presence of AS-exosomes reduced the proliferation of FOXP3+ Treg cells and decreased the frequency of FOXP3+IRF4+ Treg cells. miRNA sequencing identified 24 differentially expressed miRNAs found in circulating exosomes of patients with AS compared with HC; 22 of which were upregulated and 2 were downregulated.

CONCLUSIONS

Individuals with AS have different immunological and genetic profiles, as determined by evaluating the exosomes of these patients. The inhibitory effect of exosomes on Treg in AS suggests a mechanism contributing to chronically activated T cells in this disease.

Incidence and predictors of demyelinating disease in spondyloarthritis: data from a longitudinal cohort study

OBJECTIVES

To investigate the incidence of demyelinating disease (DD) among spondyloarthritis (SpA) patients and identify risk factors that predict DD in this patient population.

METHODS

Axial SpA (axSpA) and psoriatic arthritis (PsA) patients were identified from a longitudinal cohort database. Each group was analysed according to the presence or absence of DD. Incidence rates (IR) of DD were obtained with competing risk analysis. Cox regression analysis with Fine and Grey's method was used to evaluate predictors of DD development.

RESULTS

Among 2260 patients with follow-up data, we identified 18 DD events corresponding to an average IR of 31 per 100 000 persons per year for SpA. The IR of DD at 20 years was higher in axSpA than in PsA (1.30% vs 0.13%, p= 0.01). The risk factors retained in the best predictive model for DD development included ever- (versus never-) smoking (HR 2.918, 95% CI 1.037-8.214, p= 0.0426), axSpA (versus PsA) (HR 8.790, 95% CI 1.242-62.182, p= 0.0294), and presence (versus absence) of IBD (HR 5.698, 95% CI 2.083-15.589, p= 0.0007). History of TNFi therapy was not a predictor of DD.

CONCLUSION

The overall incidence of DD in this SpA cohort was low. Incident DD was higher in axSpA than in PsA. A diagnosis of axSpA, the presence of IBD, and ever-smoking predicted the development of DD. History of TNFi use was not found to be a predictor of DD in this cohort.

Efficacy and safety of upadacitinib in patients with ankylosing spondylitis refractory to biologic therapy: 1-year results from the open-label extension of a phase III study

BACKGROUND

Upadacitinib, a Janus kinase inhibitor, has demonstrated efficacy and an acceptable safety profile in patients with ankylosing spondylitis (AS) in the phase III SELECT-AXIS programs. We report the 1-year efficacy and safety in patients with AS and an inadequate response to biologic disease-modifying antirheumatic drugs (bDMARD-IR) from the SELECT-AXIS 2 study.

METHODS

Patients ≥ 18 years with active AS who met the modified New York criteria for AS and were bDMARD-IR received double-blind upadacitinib 15 mg once daily (QD) or placebo for 14 weeks. Patients who completed 14 weeks could enter an open-label extension and receive upadacitinib 15 mg QD for up to 2 years. Efficacy endpoints included the percentage of patients achieving ≥ 40% improvement in Assessment of SpondyloArthritis international Society response (ASAS40), Ankylosing Spondylitis Disease Activity Score (ASDAS) low disease activity (LDA), and ASDAS inactive disease (ID); and change from baseline in total and nocturnal back pain, and Bath Ankylosing Spondylitis Functional Index (BASFI). Subgroup analyses (bDMARD lack of efficacy versus intolerance, and prior tumor necrosis factor inhibitor [TNFi] versus interleukin-17 inhibitor [IL-17i] exposure) were conducted. Binary and continuous efficacy endpoints were assessed using non-responder imputation with multiple imputation (NRI-MI) and as observed (AO) analyses; and mixed-effects model repeated measures (MMRM) and AO, respectively. Safety was assessed based on adverse events. Data through week 52 are reported.

RESULTS

Of 420 randomized patients, 366 (continuous upadacitinib: n = 181; placebo to upadacitinib: n = 185) completed 52 weeks of treatment. At week 52, in the continuous upadacitinib and placebo to upadacitinib groups, ASAS40, ASDAS LDA, and ASDAS ID were achieved by 66% and 65%, 57% and 55%, and 26% and 25% (all NRI-MI); and change from baseline in total back pain, nocturnal back pain, and BASFI was -4.5 and -4.3, -4.6 and -4.4, and -3.6 and -3.5 (all MMRM), respectively. No new safety risks were identified. Subgroup analyses were consistent with the overall study population.

CONCLUSIONS

Upadacitinib 15 mg QD demonstrated sustained improvement up to 52 weeks in bDMARD-IR patients with AS. Efficacy was generally similar in patients with lack of efficacy versus intolerance to bDMARDs and prior TNFi versus IL-17i exposure.

TRIAL REGISTRATION

NCT02049138.

Third and Fourth Vaccine Doses Broaden and Prolong Immunity to SARS-CoV-2 in Adult Patients with Immune-Mediated Inflammatory Diseases

Previous studies have reported impaired humoral responses after SARS-CoV-2 mRNA vaccination in patients with immune-mediated inflammatory diseases (IMIDs), particularly those treated with anti-TNF biologics. We previously reported that IMID patients diagnosed with inflammatory bowel disease, psoriasis, psoriatic arthritis, ankylosing spondylitis, or rheumatoid arthritis exhibited greater waning of Ab and T cell responses than healthy control subjects after SARS-CoV-2 vaccine dose 2. Fewer data are available on the effects of third and fourth doses. This observational cohort study collected plasma and PBMCs from healthy control subjects and untreated or treated patients with IMIDs prevaccination and after one to four doses of SARS-CoV-2 mRNA vaccine (BNT162b2 or mRNA-1273). SARS-CoV-2-specific Ab levels, neutralization, and T cell cytokine release were measured against wild-type and Omicron BA.1 and BA.5 variants of concern. Third vaccine doses substantially restored and prolonged Ab and T cell responses in patients with IMIDs and broadened responses against variants of concern. Fourth-dose effects were subtle but also prolonged Ab responses. However, patients with IMIDs treated with anti-TNF, especially patients with inflammatory bowel disease, exhibited lower Ab responses even after the fourth dose. Although T cell IFN-γ responses were maximal after one dose, IL-2 and IL-4 production increased with successive doses, and early production of these cytokines was predictive of neutralization responses at 3-4 mo postvaccination. Our study demonstrates that third and fourth doses of the SARS-CoV-2 mRNA vaccines sustain and broaden immune responses to SARS-CoV-2, supporting the recommendation for three- and four-dose vaccination regimens in patients with IMIDs.

Real-World Retention and Clinical Effectiveness of Secukinumab for Axial Spondyloarthritis: Results From the Canadian Spondyloarthritis Research Network

OBJECTIVE

Axial spondyloarthritis (axSpA) is a chronic, immune-mediated, inflammatory condition consisting of 2 clinical subsets: nonradiographic axSpA and ankylosing spondylitis, the latter having an estimated prevalence of 0.2% to 1% in Canada. Secukinumab (SEC) received Health Canada approval in 2016 for the treatment of adults with axSpA who have responded inadequately to conventional treatment, and has demonstrated efficacy and safety through extensive clinical trials. However, there is limited evidence on its real-world use in Canada. The objective of this study was to use the Canadian Spondyloarthritis (CanSpA) Research Network to describe real-world retention and effectiveness of SEC in the Canadian axSpA population.

METHODS

This was an observational cohort study of Canadian patients with axSpA aged 18 to 65 years within the CanSpA network who had received treatment with SEC. Patients were indexed on the first date of SEC initiation. Retention and clinical effectiveness were assessed at 12 months postindex. Clinical effectiveness was measured as the proportion in remission and change in disease activity using multiple clinical indices.

RESULTS

A total of 146 patients were included. Overall retention was estimated at 62.9%. Low disease activity (ie, Bath Ankylosing Spondylitis Disease Activity Index < 4) was achieved in 29.2% of patients, and 2% had achieved remission based on the Ankylosing Spondylitis Disease Activity Score. Bath Ankylosing Spondylitis Metrology Index scores improved by more than 60% from baseline to 12 months.

CONCLUSION

The results of this real-world study of Canadian patients with axSpA, one of the first of its kind, support the effectiveness of SEC for treatment of axSpA. The CanSpA network presents an opportunity to continue building and improving the real-world evidence base for treatment of Canadian patients with spondyloarthritis.

Sustained low functional impairment in axial spondyloarthritis (axSpA): which are the primary outcomes that should be targeted to achieve this?

OBJECTIVES

To (i) determine whether sustained disease activity states, as measured by Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Ankylosing Spondylitis Disease Activity Score (ASDAS), impact function, and (ii) evaluate characteristics predicting sustained low functional impairment in a prospective axial spondyloarthritis (axSpA) cohort.

METHODS

Biologic Treatment Registry Across Canada (BioTRAC) was a multi-center, prospective registry that collected real-world data on axSpA patients receiving infliximab or golimumab between 2006 and 2017. Generalized estimating equations (GEE) were used to test baseline characteristics, treatment, and duration (at 6 and 12 months vs. only at 6 or 12 months vs. neither) of low BASDAI (< 3), ASDAS-inactive disease (ID)(< 1.3), and ASDAS-low disease activity (LDA) in predicting sustained low Bath Ankylosing Spondylitis Functional Index (BASFI)(< 3) between 12 and 18 months. The adjusted impact of achieving low disease state at 6 and/or 12 months on BASFI at 18 months was analyzed by generalized linear models.

RESULTS

Eight hundred ten patients were enrolled. 33.7%, 13.4%, and 24.7% achieved sustained low BASDAI, ASDAS-ID, and ASDAS-LDA, respectively. In univariable GEE of baseline variables, age and baseline BASDAI, BASFI, and ASDAS significantly predicted sustained low BASFI. In multivariable GEE, sustained low BASDAI (p < 0.001), low BASDAI only at 6 or 12 months (p = 0.001), and baseline BASFI (p < 0.001) were the only predictors of sustained low BASFI. Sustained ASDAS-ID (p = 0.040) and ASDAS-LDA (p < 0.001) were also predictors when forced into the model. Similar results were obtained when evaluating the BASFI score at 18 months.

CONCLUSION

Sustained BASDAI < 3 may be a valid and feasible target for a treat-to-target strategy in axSpA having function as treatment goal.

Biology and therapeutic potential of mesenchymal stem cell extracellular vesicles in axial spondyloarthritis

Axial spondyloarthritis (AxSpA) is a chronic, inflammatory, autoimmune disease that predominantly affects the joints of the spine, causes chronic pain, and, in advanced stages, may result in spinal fusion. Recent developments in understanding the immunomodulatory and tissue-differentiating properties of mesenchymal stem cell (MSC) therapy have raised the possibility of applying such treatment to AxSpA. The therapeutic effectiveness of MSCs has been shown in numerous studies spanning a range of diseases. Several studies have been conducted examining acellular therapy based on MSC secretome. Extracellular vesicles (EVs) generated by MSCs have been proven to reproduce the impact of MSCs on target cells. These EVs are associated with immunological regulation, tissue remodeling, and cellular homeostasis. EVs' biological effects rely on their cargo, with microRNAs (miRNAs) integrated into EVs playing a particularly important role in gene expression regulation. In this article, we will discuss the impact of MSCs and EVs generated by MSCs on target cells and how these may be used as unique treatment strategies for AxSpA.

Cutting Edge: Negative Regulation of Inflammasome Activation by TRAF1 Can Limit Gout

Secretion of IL-1β, a potent cytokine that plays a key role in gout pathogenesis, is regulated by inflammasomes. TRAF1 has been linked to heightened risk to inflammatory arthritis. In this article, we show that TRAF1 negatively regulates inflammasome activation to limit caspase-1 and IL-1β secretion in human and mouse macrophages. TRAF1 reduces linear ubiquitination and subsequent oligomerization of the adapter protein, ASC. i.p. injection of monosodium urate crystals resulted in increased inflammatory cell infiltrates and IL-1β production in Traf1 knockout mice compared with wild type littermates. In a model of monosodium urate crystal-induced gout, Traf1 knockout mice exhibited more swelling in the knee joints, increased infiltration of inflammatory cells, and higher expression of proinflammatory cytokines. In summary, this study identifies TRAF1 as a key regulator of IL-1β production and a potential therapeutic target for inflammasome-driven diseases such as gout.

Platelet-Derived Growth Factor B Is a Key Element in the Pathological Bone Formation of Ankylosing Spondylitis

Enthesophyte formation plays a crucial role in the development of spinal ankylosis in ankylosing spondylitis (AS). We aimed to investigate the role of platelet-derived growth factor B (PDGFB) in enthesophyte formation of AS using in vitro and in vivo models and to determine the association between PDGFB and spinal progression in AS. Serum PDGFB levels were measured in AS patients and healthy controls (HC). Human entheseal tissues attached to facet joints or spinous processes were harvested at the time of surgery and investigated for bone-forming activity. The impact of a pharmacological agonist and antagonist of platelet-derived growth factor B receptor (PDGFRB) were investigated respectively in curdlan-treated SKG mice. PDGFB levels were elevated in AS sera and correlated with radiographic progression of AS in the spine. Mature osteoclasts secreting PDGFB proteins were increased in the AS group compared with HC and were observed in bony ankylosis tissues of AS. Expression of PDGFRB was significantly elevated in the spinous enthesis and facet joints of AS compared with controls. Moreover, recombinant PDGFB treatment accelerated bone mineralization of enthesis cells, which was pronounced in AS, whereas PDGFRB inhibition efficiently reduced the PDGFB-induced bone mineralization. Also, PDGFRB inhibition attenuated the severity of arthritis and enthesophyte formation at the joints of curdlan-treated SKG mice. This study suggests that regulating PDGFB/PDGFRB signaling could be a novel therapeutic strategy to block key pathophysiological processes of AS. © 2022 American Society for Bone and Mineral Research (ASBMR).

Vesicular traffic-mediated cell-to-cell signaling at the immune synapse in Ankylosing Spondylitis

The chronic inflammatory disease ankylosing spondylitis (AS) is marked by back discomfort, spinal ankylosis, and extra-articular symptoms. In AS, inflammation is responsible for both pain and spinal ankylosis. However, the processes that sustain chronic inflammation remain unknown. Despite the years of research conducted to decipher the intricacy of AS, little progress has been made in identifying the signaling events that lead to the development of this disease. T cells, an immune cell type that initiates and regulates the body's response to infection, have been established to substantially impact the development of AS. T lymphocytes are regarded as a crucial part of adaptive immunity for the control of the immune system. A highly coordinated interaction involving antigen-presenting cells (APCs) and T cells that regulate T cell activation constitutes an immunological synapse (IS). This first phase leads to the controlled trafficking of receptors and signaling mediators involved in folding endosomes to the cellular interface, which allows the transfer of information from T cells to APCs through IS formation. Discrimination of self and nonself antigen is somatically learned in adaptive immunity. In an autoimmune condition such as AS, there is a disturbance of self/nonself antigen discrimination; available findings imply that the IS plays a preeminent role in the adaptive immune response. In this paper, we provide insights into the genesis of AS by evaluating recent developments in the function of vesicular trafficking in IS formation and the targeted release of exosomes enriched microRNAs (miRNA) at the synaptic region in T cells.

Can we characterize A-P/IAP behavioural phenotypes in people with chronic pain?

Two behavioural phenotypes in healthy people have been delineated based on their intrinsic attention to pain (IAP) and whether their reaction times (RT) during a cognitively-demanding task are slower (P-type) or faster (A-type) during experimental pain. These behavioural phenotypes were not previously studied in chronic pain populations to avoid using experimental pain in a chronic pain context. Since pain rumination (PR) may serve as a supplement to IAP without needing noxious stimuli, we attempted to delineate A-P/IAP behavioural phenotypes in people with chronic pain and determined if PR can supplement IAP. Behavioural data acquired in 43 healthy controls (HCs) and 43 age-/sex-matched people with chronic pain associated with ankylosing spondylitis (AS) was retrospectively analyzed. A-P behavioural phenotypes were based on RT differences between pain and no-pain trials of a numeric interference task. IAP was quantified based on scores representing reported attention towards or mind-wandering away from experimental pain. PR was quantified using the pain catastrophizing scale, rumination subscale. The variability in RT was higher during no-pain trials in the AS group than HCs but was not significantly different in pain trials. There were no group differences in task RTs in no-pain and pain trials, IAP or PR scores. IAP and PR scores were marginally significantly positively correlated in the AS group. RT differences and variability were not significantly correlated with IAP or PR scores. Thus, we propose that experimental pain in the A-P/IAP protocols can confound testing in chronic pain populations, but that PR could be a supplement to IAP to quantify attention to pain.

Real-World Retention and Clinical Effectiveness of Secukinumab for Psoriatic Arthritis: Results From the Canadian Spondyloarthritis Research Network

OBJECTIVE

Psoriatic arthritis (PsA) is an immune-mediated disease characterized by pain, stiffness, and swelling of peripheral joints, with an estimated prevalence in Canada of 0.45%. Treatment aims to minimize disease activity, reduce progression of damage, and improve quality of life. Secukinumab (SEC) is a biologic disease-modifying antirheumatic drug (bDMARD) that has demonstrated efficacy and safety for PsA in clinical trials; however, there is limited real-world evidence on its use in Canada. The objective of this study was to use the Canadian Spondyloarthritis (CanSpA) Research Network to describe real-world retention and effectiveness of SEC among Canadian patients with PsA.

METHODS

This was an observational cohort study of Canadian patients with PsA, 18 to 65 years of age, who attended a clinic of the CanSpA network and received treatment with SEC. Patients were indexed on the date they first initiated SEC. Retention was assessed at 12 months postindex. Clinical effectiveness was measured as the proportion of patients in remission and change in disease activity from baseline to 12 months using several clinical indices.

RESULTS

In total, 213 patients were included. Overall retention was estimated at 73.6% at 12 months (81.8% for bDMARD- or targeted synthetic DMARD-naïve patients). Out of 110 patients, 17 (15.5%) were in remission based on the Disease Activity Index in Psoriatic Arthritis in 28 joints, and 10 out of 70 patients (14.3%) were in remission based on the Psoriatic Arthritis Disease Activity Score at 12 months. The Psoriasis Area and Severity Index improved by 65.8%; the tender joint count in 68 joints and the swollen joint count in 66 joints improved by 65.5% and 73.7%, respectively.

CONCLUSION

This is the first nationwide study that we know of to describe real-world use of SEC in Canada for PsA, and the results support its effectiveness in a Canadian real-world setting. The CanSpA network represents a unique opportunity to build and improve the real-world evidence base for SpA treatment in Canada.

Work-Related Issues and Physical and Psychological Burden in Canadian Patients With Axial Spondyloarthritis: Results From the International Map of Axial Spondyloarthritis

OBJECTIVE

To identify factors associated with work-related issues in Canadian patients with axial spondyloarthritis.

METHODS

Data from 542 Canadian patients who participated in the International Map of Axial Spondyloarthritis online survey were analyzed. Participants who were employed, unemployed, or on short-term disability were included in this analysis. Regression analysis was used to study the association between work-related issues, disease activity (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]), and psychological distress (12-item General Health Questionnaire [GHQ-12]).

RESULTS

The mean age of surveyed participants was 44.3 (SD 13.9) years, 81% were university educated, and 52.6% employed. A substantial proportion had high disease activity (BASDAI ≥ 4, 72.1%) and psychological distress (GHQ-12 ≥ 3, 53.1%); 81% had work-related issues. This study analyzed responses from a subset of participants who were either employed, unemployed, or on short-term disability (n = 339). Ninety percent of this subset reported at least 1 work-related issue in the year before questionnaire completion, with the most frequent being absenteeism (49.3%) and missing work for healthcare provider visits (42.5%). Factoring in disability benefits eliminated the association between work-related issues and disease activity for all variables except fatigue (r = 0.217; P = 0.03) and discomfort (r = 0.196; P = 0.047). Difficulty fulfilling working hours (β 2.342, 95% CI 1.413-3.272) and effect on professional advancement (β 1.426, 95% CI 0.355-2.497) were associated with psychological distress. In the presence of disability benefits, only the effect on professional advancement remained (β 2.304, 95% CI 0.082-4.527).

CONCLUSION

Work-related issues are associated with worse patient-reported outcomes, both physical and psychological.

A Hidden Markov Model reveals magnetoencephalography spectral frequency-specific abnormalities of brain state power and phase-coupling in neuropathic pain

Neuronal populations in the brain are engaged in a temporally coordinated manner at rest. Here we show that spontaneous transitions between large-scale resting-state networks are altered in chronic neuropathic pain. We applied an approach based on the Hidden Markov Model to magnetoencephalography data to describe how the brain moves from one activity state to another. This identified 12 fast transient (~80 ms) brain states including the sensorimotor, ascending nociceptive pathway, salience, visual, and default mode networks. Compared to healthy controls, we found that people with neuropathic pain exhibited abnormal alpha power in the right ascending nociceptive pathway state, but higher power and coherence in the sensorimotor network state in the beta band, and shorter time intervals between visits of the sensorimotor network, indicating more active time in this state. Conversely, the neuropathic pain group showed lower coherence and spent less time in the frontal attentional state. Therefore, this study reveals a temporal imbalance and dysregulation of spectral frequency-specific brain microstates in patients with neuropathic pain. These findings can potentially impact the development of a mechanism-based therapeutic approach by identifying brain targets to stimulate using neuromodulation to modify abnormal activity and to restore effective neuronal synchrony between brain states.

Isolated axial disease in psoriatic arthritis and ankylosing spondylitis with psoriasis

OBJECTIVES

To compare isolated axial psoriatic arthritis (PsA), axial PsA with peripheral involvement and isolated axial ankylosing spondylitis (AS) with psoriasis. To evaluate predictors for developing peripheral disease from isolated axial PsA over time.

METHODS

Two PsA and AS cohorts identified patients with PsA with axial disease and isolated axial patients with AS with psoriasis. Logistic regression compared isolated axial PsA to axial PsA with peripheral involvement and isolated axial AS with psoriasis. Cox proportional hazards model evaluated predictors for developing peripheral disease from isolated axial PsA.

RESULTS

Of 1576 patients with PsA, 2.03% had isolated axial disease and 29.38% had axial and peripheral disease. human leucocyte antigen HLA-B*27 positivity (OR 25.00, 95% CI 3.03 to 206.11) and lower Health Assessment Questionnaire scores (OR 0.004, 95% CI 0.00 to 0.28) were associated with isolated axial disease. HLA-B*27 also predicted peripheral disease development over time (HR 7.54, 95% CI 1.79 to 31.77). Of 1688 patients with AS, 4.86% had isolated axial disease with psoriasis. Isolated axial patients with PsA were older at diagnosis (OR 1.06, 95% CI 1.01 to 1.13), more likely to have nail lesions (OR 12.37, 95% CI 2.22 to 69.07) and less likely to have inflammatory back pain (OR 0.12, 95% CI 0.02 to 0.61) compared with patients with isolated axial AS with psoriasis.

CONCLUSIONS

Isolated axial PsA and AS with psoriasis are uncommon. HLA-B*27 positivity is associated with isolated axial PsA and may identify those who develop peripheral disease over time. Isolated axial PsA is associated with better functional status. Isolated axial PsA appears clinically distinct from isolated axial AS with psoriasis.

Efficacy and safety of upadacitinib for active ankylosing spondylitis refractory to biological therapy: a double-blind, randomised, placebo-controlled phase 3 trial

Objectives

To evaluate the efficacy and safety of upadacitinib, a Janus kinase inhibitor, in patients with active ankylosing spondylitis (AS) with an inadequate response (IR) to biological disease-modifying antirheumatic drugs (bDMARDs).

Methods

Adults with active AS who met modified New York criteria and had an IR to one or two bDMARDs (tumour necrosis factor or interleukin-17 inhibitors) were randomised 1:1 to oral upadacitinib 15 mg once daily or placebo. The primary endpoint was Assessment of SpondyloArthritis international Society 40 (ASAS40) response at week 14. Sequentially tested secondary endpoints included Ankylosing Spondylitis Disease Activity score, Spondyloarthritis Research Consortium of Canada MRI spine inflammation score, total back pain, nocturnal back pain, Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Metrology Index and Maastricht Ankylosing Spondylitis Enthesitis Score. Results are reported from the 14-week double-blind treatment period.

Results

A total of 420 patients with active AS were randomised (upadacitinib 15 mg, n=211; placebo, n=209). Significantly more patients achieved the primary endpoint of ASAS40 at week 14 with upadacitinib vs placebo (45% vs 18%; p<0.0001). Statistically significant improvements were observed with upadacitinib vs placebo for all multiplicity-controlled secondary endpoints (p<0.0001). Adverse events were reported for 41% of upadacitinib-treated and 37% of placebo-treated patients through week 14. No events of malignancy, major adverse cardiovascular events, venous thromboembolism or deaths were reported with upadacitinib.

Conclusion

Upadacitinib 15 mg was significantly more effective than placebo over 14 weeks of treatment in bDMARD-IR patients with active AS. No new safety risks were identified with upadacitinib.

Trial registration number

NCT04169373.

Accelerated waning of immunity to SARS-CoV-2 mRNA vaccines in patients with immune-mediated inflammatory diseases

BACKGROUNDLimited information is available on the impact of immunosuppressants on COVID-19 vaccination in patients with immune-mediated inflammatory diseases (IMID).METHODSThis observational cohort study examined the immunogenicity of SARS-CoV-2 mRNA vaccines in adult patients with inflammatory bowel disease, rheumatoid arthritis, ankylosing spondylitis, or psoriatic disease, with or without maintenance immunosuppressive therapies. Ab and T cell responses to SARS-CoV-2, including neutralization against SARS-CoV-2 variants, were determined before and after 1 and 2 vaccine doses.RESULTSWe prospectively followed 150 subjects, 26 healthy controls, 9 patients with IMID on no treatment, 44 on anti-TNF, 16 on anti-TNF with methotrexate/azathioprine (MTX/AZA), 10 on anti-IL-23, 28 on anti-IL-12/23, 9 on anti-IL-17, and 8 on MTX/AZA. Ab and T cell responses to SARS-CoV-2 were detected in all participants, increasing from dose 1 to dose 2 and declining 3 months later, with greater attrition in patients with IMID compared with healthy controls. Ab levels and neutralization efficacy against variants of concern were substantially lower in anti-TNF-treated patients than in healthy controls and were undetectable against Omicron by 3 months after dose 2.CONCLUSIONSOur findings support the need for a third dose of the mRNA vaccine and for continued monitoring of immunity in these patient groups.FUNDINGFunded by a donation from Juan and Stefania Speck and by Canadian Institutes of Health (CIHR)/COVID-Immunity Task Force (CITF) grants VR-1 172711 and VS1-175545 (to THW and ACG), CIHR FDN-143250 (to THW), GA2-177716 (to VC, ACG, and THW), and GA1-177703 (to ACG) and the CIHR rapid response network to SARS-CoV-2 variants, CoVaRR-Net (to ACG).

Motivators, Barriers, and Opportunity for E-Health to Encourage Physical Activity in Axial Spondyloarthritis: A Qualitative Descriptive Study

OBJECTIVE

Physical activity is fundamental in the management of axial spondyloarthritis (SpA); however, evidence suggests that patients with axial SpA are not adhering to physical activity recommendations. E-health technology (e.g., telephone reminders and mobile text messaging) can increase participation in physical activity. The aims of this study were as follows: 1) to understand perspectives of the importance of physical activity in the management of axial SpA; 2) to describe factors associated with physical activity adherence; and 3) to explore the role of e-health technology to facilitate physical activity in patients with axial SpA.

METHODS

Semistructured interviews were conducted with axial SpA patients attending an urban academic rheumatology clinic. Interviews were audio recorded and transcribed verbatim. Data were analyzed using thematic principles. Systematic labeling of the data set was completed using an inductive approach until saturation of emergent themes.

RESULTS

Twelve patient interviews were completed. Most respondents were male (83.3%) with a mean ± SD age of 45.5 ± 12.5 years and a mean ± SD disease duration of 21.5 ± 14.9 years. Participants defined physical as any activity involving physical exertion. The role of physical activity in axial SpA management was well recognized and included symptom relief, pharmacologic synergy, and impact on general health. Motivators included a growth mindset, social support networks, and facility access. Barriers included fear of disease progression, life demands, and environmental restrictions. Feedback, electronic reminders, and virtual support networks were key components of e-health technology to facilitate engagement in physical activity.

CONCLUSION

The results of this study provide a foundation to guide development of patient-centered e-health technology interventions to increase physical activity uptake in patients with axial SpA.

Characteristics of Patients With Axial Spondyloarthritis by Geographic Regions: PROOF Multicountry Observational Study Baseline Results

Objectives

To compare demographic and clinical characteristics of patients with axial SpA (axSpA) across geographic regions.

Methods

Patients With Axial Spondyloarthritis: Multicountry Registry of Clinical Characteristics (PROOF) is an observational study that enrolled recently diagnosed (≤1 year) axSpA patients fulfilling the Assessment of SpondyloArthritis international Society classification criteria from rheumatology clinical practices in 29 countries across six geographic regions. Demographics and disease-related parameters were collected. Here we present baseline data for patients who were classified as radiographic axSpA (r-axSpA) or non-radiographic axSpA (nr-axSpA) confirmed by central reading.

Results

Of the 2170 patients enrolled, 1553 were classified based on central evaluation of sacroiliac radiographs [r-axSpA: 1023 (66%); nr-axSpA: 530 (34%)]. Patients with nr-axSpA had a significantly higher occurrence of enthesitis (40% vs 33%), psoriasis (10% vs 5%) and IBD (4% vs 2%) vs r-axSpA patients. Significant differences in axSpA characteristics were observed between geographic regions. The highest occurrence of peripheral arthritis (60%), enthesitis (52%) and dactylitis (12%) was in Latin America, and the lowest was in Canada (9%, 9% and 2%, respectively). The occurrence of uveitis and psoriasis was highest in Canada (18% and 14%, respectively) and lowest in China (6% and <1%, respectively). IBD was highest in Arabia (21%), and no cases were observed in China. In multivariable analysis adjusted for factors potentially affecting peripheral and extramusculoskeletal manifestations, geographic regions still exhibited significant differences in frequencies of uveitis (P < 0.01), psoriasis (P < 0.0001) and peripheral arthritis (P < 0.0001).

Conclusion

The multinational PROOF study of axSpA patients showed significant regional differences in peripheral and extramusculoskeletal manifestations of SpA, which could be considered in management guidelines and clinical trials.

Macrophage migration inhibitory factor drives pathology in a mouse model of spondyloarthritis and is associated with human disease

[Figure: see text].

Bridging the Gap between Symptom Onset and Diagnosis in Axial Spondyloarthritis

OBJECTIVE

To evaluate a stratified screening process for early identification of axial spondyloarthritis (axSpA) considering: 1) wait times from primary care to rheumatology screen; 2) incremental precision and accuracy from primary care to rheumatology screen; and 3) diagnostic delay.

METHODS

Adults with low back pain (LBP) attending primary care LBP clinics prospectively underwent a primary standardized clinical screen. Patients with LBP >3 months and onset age <50 years were referred for a comprehensive secondary screen by a physiotherapist with advanced rheumatology training. At secondary screening, patients with inflammatory features were deemed to have a low, medium, or high risk of axSpA vs. no risk. Precision and accuracy of this screening strata were measured against a rheumatologist with axSpA expertise.

RESULTS

In all, 405 patients underwent primary and secondary screening. Mean age was 36.9 years (±9.9); 55% were female. HLA-B27 was present in 14.4%. Median wait time from primary to secondary screen was 15 days. AxSpA risk assignment by rheumatologist was: 64.9% (none or low risk axSpA) and 35.1% (medium or high risk axSpA). The best combination of sensitivity (68%), specificity (90%), positive (80%) and negative (84%) predictive values was evident with the secondary screen. 15.6% of patients received a final diagnosis of axSpA. Median LBP duration from onset to diagnosis was: 2 years (non-radiographic axSpA) and 7 years (ankylosing spondylitis).

CONCLUSION

A stratified interprofessional screening process can facilitate rapid diagnosis of persistent LBP, with high precision and accuracy, in patients with axSpA.

From Science to Success? Targeting Tyrosine Kinase 2 in Spondyloarthritis and Related Chronic Inflammatory Diseases

Spondyloarthritis (SpA) is a family of inflammatory arthritic diseases, which includes the prototypes of psoriatic arthritis and ankylosing spondylitis. SpA is commonly associated with systemic inflammatory diseases, such as psoriasis and inflammatory bowel disease. Immunological studies, murine models and the genetics of SpA all indicate a pathogenic role for the IL-23/IL-17 axis. Therapeutics targeting the IL-23/IL-17 pathway are successful at providing symptomatic relief, but may not provide complete protection against progression of arthritis. Thus there is still tremendous interest in the discovery of novel therapeutic targets for SpA. Tyrosine kinase 2 (TYK2) is a member of the Janus kinases, which mediate intracellular signaling of cytokines via signal transducer and activator of transcription (STAT) activation. TYK2 plays a crucial role in mediating IL-23 receptor signaling and STAT3 activation. A plethora of natural mutations in and around TYK2 have provided a wealth of data to associate this kinase with autoimmune/autoinflammatory diseases in humans. Induced and natural mutations in murine Tyk2 largely support human data; however, key inter-species differences exist, which means extrapolation of data from murine models to humans needs to be done with caution. Despite these reservations, novel selective TYK2 inhibitors are now proving successful in advanced clinical trials of inflammatory diseases. In this review, we will discuss TYK2 from basic biology to therapeutic targeting, with an emphasis on studies in SpA. Seminal studies uncovering the basic science of TYK2 have provided sound foundations for targeting it in SpA and related inflammatory diseases. TYK2 inhibitors may well be the next blockbuster therapeutic for SpA.

Serial Lipocalin 2 and Oncostatin M levels reflect inflammation status and treatment response in axial spondyloarthritis

Background

Informative serum biomarkers for monitoring inflammatory activity and treatment responses in axial spondyloarthritis (axSpA) are lacking. We assessed whether Lipocalin 2 (LCN2) and Oncostatin M (OSM), both having roles in inflammation and bone remodeling, may accurately reflect chronic joint inflammation and treatment response in axSpA. Previous reports in animal models showed involvement of LCN2 and OSM in joint/gut inflammation. We asked whether they also play a role in human axSpA.

Methods

We analyzed a longitudinal observational axSpA cohort (286 patients) with yearly clinical assessments and concurrent measurements of serum LCN2 and OSM (1204 serum samples) for a mean of 4 years. Biomarker levels were correlated with MRI scoring and treatment response.

Results

Persistent and transient elevation of LCN2 and OSM were observed in axSpA patients. Persistent elevation of LCN2 or OSM, but not CRP, correlated with sacroiliac joint (SIJ) MRI SPARCC scores (Pearson’s correlation p = 0.0005 and 0.005 for LCN2 and OSM respectively), suggesting that LCN2/OSM outperforms CRP as reflective of SIJ inflammation. We observed both concordant and discordant patterns of LCN2 and OSM in relationship to back pain, the cardinal clinical symptom in axSpA. Twenty-six percent (73/286) of the patients remained both clinically and serologically active (CASA). Sixty percent (173/286) of the patients became clinically quiescent, with back pain resolved, but 53% (92/173) of them were serologically active (CQSA), indicating that pain control may not indicate control of joint inflammation, as reflected by positive MRI imaging of SIJ. With respect to treatment responses, transient elevation of LCN2 or OSM over time was predictive of better response to all treatments.

Conclusion

In axSpA, persistent LCN2 and/or OSM elevation reflects chronic SIJ inflammation and suboptimal treatment response. In our cohort, half of the currently deemed clinically quiescent patients with back pain resolved continued to demonstrate chronic joint inflammation. LCN2 and OSM profiling outperforms CRP as a predictive measure and provides an objective assessment of chronic local inflammation in axSpA patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02521-y.

Axial Spondyloarthritis: Current Advances, Future Challenges

Axial spondyloarthritis (axSpA) is a chronic inflammatory joint disease with a predilection for the spine. It affects young adults and has the potential to have a major impact on quality of life, not only because of the chronic pain and fatigue, but also because of the potential for marked disability related to spinal ankylosis. Early detection of axSpA remains a major challenge, for which there is a heightened sense of urgency since it has been shown that earlier intervention with biologics can alter the progression of radiographic change in the spine. Advances in the genetics of axSpA have highlighted a number of candidate genes conferring susceptibility to the disease, but there is evidence of environmental factors playing a role as well. Recently studies in both clinical and experimental axSpA have implicated alterations in the gut microbiome as playing a key role, and the immunology of the gut-joint axis is becoming better understood. The unmet needs which are shaping the research agenda include improvement in early case identification, sensitive and specific biomarkers which could accurately reflect disease activity and severity, improved understanding of the common pathways of inflammation in the skin, eye and gut in axSpA, and novel therapeutic targets which could have curative potential.

Axial Disease in Psoriatic arthritis: The presence and progression of unilateral grade 2 sacroiliitis in a psoriatic arthritis cohort

BACKGROUND/PURPOSE

A universally accepted definition of axial psoriatic arthritis (axPsA) is lacking. We aimed to 1) assess the presence of axial involvement as defined by "at least unilateral grade 2 sacroiliitis (Uni2SI)" and 2) assess the radiographic progression of Uni2SI and identify risk factors for progression.

METHODS

PsA patients participating in a prospective observational cohort were classified according to their highest sacroiliitis grade. The baseline features of patients with Uni2SI were compared to patients meeting the radiographic criteria of the modified New York Ankylosing Spondylitis (mNY AS) criteria. Risk factors were examined for progression from Uni2SI in a sub-group of patients with >1 follow-up radiographs. Logistic regression and a survival analysis were carried out and identified risk factors associated with radiographic mNY AS compared to Uni2SI.

RESULTS

Axial disease defined as ≥Uni2SI was detected in 612/1354 patients (45%). mNY AS sacroiliitis was observed in 477 patients (35%). Radiographic progression of Uni2SI was assessed in 154 patients, 80 (52%) progressed to mNY AS criteria within 5.5 years. At baseline, progressors were diagnosed at a younger age (35.6 vs. 38.9, p = 0.05), had less degenerative disc disease (OR = 0.47, p = 0.02), worse peripheral radiographic damage (OR=1.02, p = 0.03) and worse psoriasis (OR = 1.09, p = 0.01) compared to non-progressors. Patients with an elevated erythrocyte sedimentation rate were more likely to progress (HR = 1.83, p = 0.02), while patients with longer disease duration were less likely to progress (HR = 0.95, p = 0.02).

CONCLUSION

The radiographic mNY AS criteria appear to be suitable for defining axial PsA according to radiographs. MRI definitions are needed as well for the most appropriate definition of axial PsA.

Pain in Axial Spondyloarthritis: Insights from Immunology and Brain Imaging

Inflammatory back pain is characteristic of spondyloarthritis (SpA); however, this pain may not respond to treatment with NSAIDs or biologics. Pain is multifactorial and a combination of mechanical and inflammatory factors. A growing body of literature examines the impact of emotions on pain in SpA; many patients with this condition suffer from depression and fibromyalgia. Advanced imaging techniques can investigate the interplay of various brain networks in pain perception. Animal models have helped understand the interplay between the immune and nervous systems in pain generation and have highlighted differences in pain perception between the sexes.

The gut-joint axis in spondyloarthritis: immunological, microbial, and clinical insights

The strong genetic and clinical overlaps between spondyloarthritis (SpA) and inflammatory bowel disease (IBD) have placed much needed focus on the gut-joint axis of inflammation in SpA, leading to three key hypotheses that attempt to unravel this complex relationship. The arthritogenic peptide hypothesis and the aberrant cellular trafficking hypothesis have been put forth to rationalize the manner by which the innate and adaptive immune systems cooperate and converge during SpA pathogenesis. The bacterial dysbiosis hypothesis discusses how changes in the microbiome lead to architectural and immunological consequences in SpA. These theories are not mutually exclusive, but can provide an explanation as to why subclinical gut inflammation may sometimes precede joint inflammation in SpA patients, thereby implying a causal relationship. Such investigations will be important in informing therapeutic decisions which may be common to both SpA and IBD. However, these hypotheses can also offer insights for a coincident inflammatory relationship between the gut and the joint, particularly when assessing the immunological players involved. Insights from understanding how these systems might affect the gut and joint differently will be equally imperative to address where the therapeutic differences lie between the two diseases. Collectively, this knowledge has practical implications in predicting the likelihood of IBD development in SpA or presence of coincident SpA-IBD, uncovering novel therapeutic targets, and redesigning currently approved treatments. It is evident that a multidisciplinary approach between the rheumatology and gastroenterology fields cannot be ignored, when it comes to the care of SpA patients at risk of IBD or vice versa.

Recent advances on the role of cytotoxic T lymphocytes in the pathogenesis of spondyloarthritis

Spondyloarthritis (SpA) is a chronic inflammatory disorder with complex etiology and pathogenesis. Its pathogenesis likely involves a combination of different factors. These factors include host genetics, environmental triggers, and immune and microbiota dysregulation. One of the strongest genetic associations with SpA is HLA-B27, implicating the involvement of cytotoxic T lymphocytes (CTLs) in SpA pathogenesis. Despite this discovery dating back decades ago, the CTL compartment that underlies SpA inflammation has yet to be fully defined until recently. Indeed, recent published studies support a significant role that CTLs play in contributing to chronic joint inflammation, which is a hallmark of SpA pathology. In this review chapter, we discuss emerging evidence that supports a newfound role of CTLs in SpA pathogenesis. This emerging evidence includes enrichment of CTL-related genes from genome-wide association studies, overrepresentation of pathogenic synovial CTL phenotype, clonal expansion, and immune dysregulation of CTLs. The discoveries of this mounting evidence suggest that CTL homeostasis is altered, and a disrupted adaptive immunity underlies the chronic inflammatory features seen in SpA pathology.

HLA, Immune Response, and Susceptibility to COVID-19

The severe acute respiratory syndrome caused by Coronavirus 2 (SARS-CoV-2) that appeared in December 2019 has precipitated the global pandemic Coronavirus Disease 2019 (COVID-19). However, in many parts of Africa fewer than expected cases of COVID-19, with lower rates of mortality, have been reported. Individual human leukocyte antigen (HLA) alleles can affect both the susceptibility and the severity of viral infections. In the case of COVID-19 such an analysis may contribute to identifying individuals at higher risk of the disease and the epidemiological level to understanding the differences between countries in the epidemic patterns. It is also recognized that first antigen exposure influences the consequence of subsequent exposure. We thus propose a theory incorporating HLA antigens, the "original antigenic sin (OAS)" effect, and presentation of viral peptides which could explain with differential susceptibility or resistance to SARS-CoV-2 infections.

Factors Predictive of Radiographic Progression in Ankylosing Spondylitis

OBJECTIVE

Using a longitudinal observational cohort of ankylosing spondylitis (AS) patients, we sought to identify progression rates and factors predictive of spinal progression. As a secondary aim, we analyzed the effect of tumor necrosis factor inhibitor (TNFi) treatment on radiographic progression.

METHODS

AS patients who had baseline and follow-up cervical and lumbar radiographs were included in the study. Radiographic damage was assessed by the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). A change of 2 mSASSS units in 2 years was defined as progression. The characteristics of the study group such as demographic, clinical, laboratory, and treatment history were collected.

RESULTS

There were 350 patients in the study. The mean ± SD mSASSS increased from 9.3 ± 15.8 units at baseline to 17.7 ± 21.7 units by the sixth year. Mean ± SD changes in mSASSS between the years 0 to 2, 2 to 4, and 4 to 6 were 1.23 ± 2.68, 1.47 ± 2.86, and 1.52 ± 3.7 units, respectively. Overall, 24.3% of the group progressed over 2 years. Male sex (hazard ratio [HR] 2.46 [95% confidence interval (95% CI) 1.05, 5.76]), the presence of baseline damage (HR 7.98 [95% CI 3.98, 16]), increased inflammatory markers (log C-reactive protein level HR 1.35 [95% CI 1.07, 1.70]), and TNFi use (HR 0.82 [95% CI 0.70, 0.96]) were predictive of radiographic progression. There was a 20% reduction in the rate of progression with TNFi.

CONCLUSION

Male sex, the presence of baseline damage, active disease state, and higher inflammatory markers confer a high risk for disease progression. Treatment with TNFi showed a disease-modifying effect by slowing the rate of radiographic progression.

TYK2 inhibition reduces type 3 immunity and modifies disease progression in murine spondyloarthritis

Spondyloarthritis (SpA) represents a family of inflammatory diseases of the spine and peripheral joints. Ankylosing spondylitis (AS) is the prototypic form of SpA in which progressive disease can lead to fusion of the spine. Therapeutically, knowledge of type 3 immunity has translated into the development of IL-23– and IL-17A–blocking antibodies for the treatment of SpA. Despite being able to provide symptomatic control, the current biologics do not prevent the fusion of joints in AS patients. Thus, there is an unmet need for disease-modifying drugs. Genetic studies have linked the Janus kinase TYK2 to AS. TYK2 is a mediator of type 3 immunity through intracellular signaling of IL-23. Here, we describe and characterize a potentially novel small-molecule inhibitor of TYK2 that blocked IL-23 signaling in vitro and inhibited disease progression in animal models of SpA. The effect of the inhibitor appears to be TYK2 specific, using TYK2-inactive mice, which further revealed a duality in the induction of IL-17A and IL-22 by IL-23. Specifically, IL-22 production was TYK2/JAK2/STAT3 dependent, while IL-17A was mostly JAK2 dependent. Finally, we examined the effects of AS-associated TYK2 SNPs on TYK2 expression and function and correlated them with AS disease progression. This work provides evidence that TYK2 inhibitors have great potential as an orally delivered therapeutic for SpA.

Is axial psoriatic arthritis distinct from ankylosing spondylitis with and without concomitant psoriasis?

OBJECTIVE

The aim of this study was to compare patients with ankylosing spondylitis with psoriasis (ASP) and without psoriasis (AS), to axial PsA (axPsA) patients.

METHODS

Two adult cohorts were recruited from the AS clinic: ASP and AS. These two cohorts were compared with two adult cohorts recruited from the PsA clinic: axPsA (radiographic sacroiliitis: ⩾bilateral grade 2 or unilateral grade 3 or 4); and Peripheral PsA. All patients were followed prospectively according to the same protocol. The demographic, clinical and radiographic variables were compared. Adjusted means were used to account for varying intervals between visits. A logistic regression was performed and adjusted for follow-up duration.

RESULTS

There were 477 axPsA patients, 826 peripheral PsA, 675 AS and 91 ASP patients included. AS patients were younger (P < 0.001), more male and HLA-B*27 positive (76%, 72% vs 64%, P ⩽ 0.001, 82%, 75%, vs 19%, P = 0.001). They had more back pain at presentation (90%, 92% vs 19%, P = 0.001), worse axial disease activity scores (bath ankylosing spondylitis disease activity index: 4.1, 3.9 vs 3.5 P = 0.017), worse back metrology (bath ankylosing spondylitis metrology index: 2.9, 2.2 vs 1.8, P < 0.001), worse physician global assessments (2.4, 2.2 vs 2.1, P < 0.001), were treated more with biologics (29%, 21% vs 7%, P = 0.001) and had a higher grade of sacroiliitis (90%, 84% vs 51%, P < 0.001). Similar differences were detected in the comparison of ASP to axPsA and in a regression model.

CONCLUSION

AS patients, with or without psoriasis, seem to be different demographically, genetically, clinically and radiographically from axPsA patients. axPsA seems to be a distinct entity.

Quantifying development to inform management of Mojave and Sonoran desert tortoise habitat in the American southwest

Two tortoise species native to the American southwest have experienced significant habitat loss from development and are vulnerable to ongoing threats associated with continued development. Mojave desert tortoises Gopherus agassizii are listed as threatened under the US Endangered Species Act, and Sonoran desert tortoises G. morafkai are protected in Arizona (USA) and Mexico. Substantial habitat for both species occurs on multiple-use public lands, where development associated with traditional and renewable energy production, recreation, and other activities is likely to continue. Our goal was to quantify development to inform and evaluate actions implemented to protect and manage desert tortoise habitat. We quantified a landscape-level index of development across the Mojave and Sonoran desert tortoise ranges using models of potential habitat for each species (152485 total observations). We used 13 years of Mojave desert tortoise monitoring data (4732 observations) to inform the levels and spatial scales at which tortoises may be affected by development. Most (66-70%) desert tortoise habitat has some development within 1 km. Development levels on desert tortoise habitat are lower inside versus outside areas protected by actions at national, state, and local levels, suggesting that protection efforts may be having the desired effects and providing a needed baseline for future effectiveness evaluations. Of the relatively undeveloped desert tortoise habitat, 43% (74030 km2) occurs outside of existing protections. These lands are managed by multiple federal, state, and local entities and private landowners, and may provide opportunities for future land acquisition or protection, including as mitigation for energy development on public lands.

Lipocalin 2 links inflammation and ankylosis in the clinical overlap of inflammatory bowel disease (IBD) and ankylosing spondylitis (AS)

Background

Little is known about the mechanisms underlying the clinical overlap between gut inflammation and joint ankylosis, as exemplified by the concurrence of inflammatory bowel diseases (IBD) and ankylosing spondylitis (AS). As dysbiosis may serve as a common contributor, the anti-microbial pleiotropic factor lipocalin 2 could be a potential mediator due to its roles in inflammation and bone homeostasis.

Methods

Baseline colonic pathology was conducted in the ank/ank mouse model. Serum lipocalin 2 was analyzed by ELISA, in ank/ank mutants versus C3FeB6-A/A^w-jwt/wt, in patients with concurrent AS-IBD, AS alone, IBD alone, or mechanical back pain, and in healthy controls. In the ank/ank mouse model, the expression of nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) was examined by real-time PCR. Intraperitoneal injection was done with the PPARγ agonist rosiglitazone or antagonist bisphenol A diglycidyl ether for four consecutive days. Serum levels of lipocalin 2 were examined on the sixth day.

Results

This study showed that the ank/ank mice with fully fused spines had concurrent colonic inflammation. By first using the ank/ank mouse model with progressive ankylosis and subclinical colonic inflammation, confirmed in patients with concurrent AS and IBD, elevated circulating lipocalin 2 levels were associated with the coexisting ankylosis and gut inflammation. The intracellular pathway of lipocalin 2 was further investigated with the ank/ank mouse model involving PPARγ. Colonic expression of PPARγ was negatively associated with the degree of gut inflammation. The PPARγ agonist rosiglitazone treatment significantly upregulated the serum levels of lipocalin 2, suggesting a potential regulatory role of PPARγ in the aberrant expression of lipocalin 2.

Conclusions

In summary, lipocalin 2 modulated by PPARγ could be a potential pathway involved in concurrent inflammation and ankylosis in AS and IBD.

Tumor Necrosis Factor Inhibitor Dose Reduction for Axial Spondyloarthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

The present study was undertaken to investigate the effectiveness and safety of dose reduction of tumor necrosis factor inhibitor (TNFi) therapy in the treatment of axial spondyloarthritis (SpA) compared to usual care.

METHODS

We searched the Cochrane Central Register of Controlled Trials, Embase, Medline, and trial registries. We screened, extracted data, and assessed risk of bias in duplicate. Data were pooled using random-effects models; subgroup analyses were performed for type of TNFi, prior TNFi exposure, and follow-up duration. Outcomes of interest were Assessment of SpondyloArthritis international Society (ASAS) response and remission criteria, disease activity, relapse, and safety.

RESULTS

We included 6 randomized trials with 747 participants (442 with ankylosing spondylitis and 305 with nonradiographic axial SpA). Compared to the standard dose, there were fewer events with the reduced dose for the ASAS criteria for 40% improvement (risk ratio [RR] 0.62 [95% confidence interval (95% CI) 0.49, 0.78]) and for ASAS partial remission (RR 0.17 [95% CI 0.06, 0.46]). There was a mean increase in the Bath Ankylosing Spondylitis Disease Activity Index score (mean difference [MD] 0.35 [95% CI 0.10, 0.60]) and no difference in C-reactive protein levels (MD 0.16 [95% CI -0.76, 1.07]) with the reduced dose. There were more disease flares/relapses (RR 1.73 [95% CI 1.32, 2.27]) with the reduced dose. There were no differences in infection rates (incidence rate ratio [IRR] 0.98 [95% CI 0.76, 1.25]) or injection/infusion reactions (IRR 0.71 [95% CI 0.42, 1.19]).

CONCLUSION

Patients with axial SpA may experience little to no clinical benefit from reduction of TNFi therapy. Maintaining the standard dose probably improves the sustained effect on disease activity and helps to prevent disease flare.

Altered Cytotoxicity Profile of CD8+ T Cells in Ankylosing Spondylitis

OBJECTIVE

Ankylosing spondylitis (AS) is an inflammatory arthritis in which men have a higher risk of developing progressive axial disease than women. Transcriptomic studies have shown reduced expression of cytotoxic cell genes in the blood of AS patients. HLA-B27 contributes the greatest risk for AS, suggesting a role for CD8+ T cells. This study was undertaken to profile AS patient cytotoxic cells with the hypothesis that an alteration in CD8+ T cells might explain the aberrant cytotoxic profile observed in patients.

METHODS

Whole blood was examined for GZM and PRF1 gene expression by quantitative polymerase chain reaction. Serum and synovial fluid (SF) were examined for granzyme and perforin 1 expression by bead array, and blood and SF mononuclear cells were examined for granzyme and perforin 1 expression by fluorescence-activated cell sorting (FACS).

RESULTS

GZM and PRF1 gene expression were both reduced in AS patients compared to healthy controls, especially in men. Perforin 1, but not granzyme, protein levels were reduced in AS patient serum. Granzymes were elevated in AS SF, but not in rheumatoid arthritis or osteoarthritis SF. FACS revealed a reduction in granzyme-positive and perforin 1-positive lymphocytes, but not an intrinsic defect in CD8+ T cell granzyme or perforin 1 production. CD8+ T cell frequency was reduced in the blood and increased in the SF of AS patients.

CONCLUSION

Our findings indicate that AS patients have an altered cytotoxic T cell profile. These data suggest that CD8+ T cells with a cytotoxic phenotype are recruited to the joints, where they exhibit an activated phenotype. Thus, a central role for CD8+ T cells in AS may have been overlooked and deserves further study.

Integrin and transcriptomic profiles identify a distinctive synovial CD8+ T cell subpopulation in spondyloarthritis

Objectives

Current evidence suggests that immune events in the gut may impact joint inflammation in ankylosing spondylitis (AS) but the expression of gut-related trafficking molecules in the inflammed joint is poorly characterised. We aimed to (1) assess differential expression patterns of trafficking molecules between patients and controls, (2) generate joint-specific cellular signatures and (3) obtain transcriptomic profiles of noteworthy cell subpopulations.

Methods

Male subjects under 40 years of age fulfilling the mNY criteria were recruited. The following cells were surface stained using a 36-marker mass cytometry antibody panel: (1) peripheral blood mononuclear cells from AS patients, and healthy controls; (2) synovial fluid mononuclear cells from AS and rheumatoid arthritis (RA) patients. Additionally, RNA-seq was performed on CD8+ T cell subpopulations from the synovial fluid (SF).

Results

Mature CD8+ T cells were enriched in AS SF, with a distinct pattern of integrin expression (β7, CD103, CD29 and CD49a). RNA-seq analysis of SF-derived CD103+CD49a+CD8+ T cells revealed elevated TNFAIP3, GZMB, PRF1 and IL-10.

Conclusions

We have identified a novel integrin-expressing mature CD8+ T cell population (CD49a+CD103+β7+CD29+) that appears to be more prevalent in AS SF than RA SF. These cells seem to possess dual cytotoxic and regulatory profiles which may play a role in AS pathogenesis.

The Prevalence and Clinical Associations of Subclinical Sacroiliitis in Inflammatory Bowel Disease

BACKGROUND

Sacroiliitis, an inflammatory arthropathy associated with ankylosing spondylitis (AS), is found in patients with inflammatory bowel disease (IBD) but may go undiagnosed. The aims of this study were to assess prevalence of sacroiliitis in IBD and to determine association between clinical characteristics of IBD and sacroiliitis.

METHODS

Inflammatory bowel disease patients undergoing abdomino-pelvic computed tomography (CT) for any indication (2006-2015) were identified. Using standardized CT scoring, sacroiliitis was confirmed. Two blinded readers used a standardised model where presence of ankylosis or erosion score >3 indicated sacroiliitis. Inflammatory bowel disease scoring was blinded to the presence of sacroiliitis. Demographics, IBD characteristics, clinical activity (Harvey Bradshaw Index >4, Mayo >2, as denoted by attending physician), endoscopic activity (Simple Endoscopic Score for Crohn's Disease >4/Mayo subscore >1), and arthritis/extraintestinal manifestations (EIMS) were recorded. Comparisons were made between those with/without sacroiliitis.

RESULTS

Three hundred sixteen patients were included (50% male; 74% Crohn's disease [CD]). Computed tomography scoring identified 49 (16%) with sacroiliitis. Radiologists had reported sacroiliitis in 33% of these. Five patients had been to a spondylitis clinic. Thirty-three of 49 had abdominal x-rays; 64% of these fulfilled the imaging component of Modified New York criteria for AS. More than 5 sacroiliac erosions were associated with radiologist-reported sacroiliitis (P < 0.0001). There was no difference in prevalence between CD and ulcerative colitis. Sacroiliitis was associated with male sex (63.3% vs 47.9%; odds ratio [OR], 1.8; P = 0.04), known arthritis (41% vs 12%; OR, 4.7; P < 0.0001), pain as an IBD symptom (77.7% vs 56.9%; P = 0.03), and CD inflammatory phenotype (P = 0.01). Endoscopic activity, location, and extent were not associated.

CONCLUSIONS

Sacroiliitis is underdiagnosed in IBD and is associated with male sex, arthritis, and inflammatory CD. Data support targeted screening in at-risk patients.

Advancing Early Identification of Axial Spondyloarthritis: An Interobserver Comparison of Extended Role Practitioners and Rheumatologists

OBJECTIVE

To compare clinical impression and confidence of extended role practitioners (ERP) with those of rheumatologists experienced in axial spondyloarthritis (axSpA) according to (1) evaluation of patients with chronic back pain assessed for axSpA; and (2) magnetic resonance imaging (MRI) recommendation for further investigation of these patients.

METHODS

Patients with ≥ 3 months of back pain and age of onset < 45 years were referred for axSpA evaluation. An ERP assessed consecutive patients and recorded standardized clinical information in written form. Three rheumatologists subsequently evaluated each patient based on the recorded information. Patients were classified as having axSpA or mechanical back pain based on clinical and investigative findings. Level of confidence was noted for classification and MRI indication. Agreement between assessors was evaluated using percentage agreement and κ coefficient.

RESULTS

Fifty-seven patients were assessed. Interobserver agreement of clinical impression for all raters was moderate (κ = 0.52). Agreement of clinical impression between ERP and rheumatologists ranged between 71.2% (κ = 0.41) and 79.7% (κ = 0.57). Agreement of clinical impression among rheumatologists ranged from 74.1% (κ = 0.49) to 79.7% (κ = 0.58). All rater agreement for MRI indication was fair (κ = 0.37). ERP agreement with rheumatologist for MRI recommendation ranged from 64.2% (κ = 0.32) to 75% (κ = 0.48). Agreement for MRI indication among rheumatologists ranged from 62.9% (κ = 0.27) to 74% (κ = 0.47). Confidence in clinical impression was similar among all practitioners.

CONCLUSION

ERP with specialty training in inflammatory arthritis demonstrate clinical impressions comparable with those of rheumatologists in the assessment of axSpA. Incorporation of such roles into existing models of care may assist in early detection of axSpA.

Efficacy and safety of continuing versus withdrawing adalimumab therapy in maintaining remission in patients with non-radiographic axial spondyloarthritis (ABILITY-3): a multicentre, randomised, double-blind study

BACKGROUND

Success of treatment withdrawal in patients with non-radiographic axial spondyloarthritis who are in remission remains unknown. The ABILITY-3 study explored the ability to withdraw adalimumab treatment in patients with non-radiographic axial spondyloarthritis who achieved sustained clinical remission after open-label treatment with adalimumab.

METHODS

ABILITY-3 was a multicentre, two-period study done in 107 sites in 20 countries. We enrolled adult patients (≥18 years) diagnosed with non-radiographic axial spondyloarthritis, fulfilling Assessment of SpondyloArthritis international Society classification criteria but not the modified New York radiologic criterion, who had objective evidence of active inflammation, active disease, and inadequate response to at least two non-steroidal anti-inflammatory drugs. Patients who achieved Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease (<1·3) with open-label adalimumab (40 mg subcutaneously every other week for 28 weeks) at weeks 16, 20, 24, and 28 were randomly assigned (1:1) using an interactive voice or web response system to 40-week, double-blind treatment with adalimumab (continuation) or placebo (withdrawal). The primary efficacy endpoint was the proportion of patients who did not experience a flare (defined as ASDAS ≥2·1 at two consecutive visits) during the double-blind period. Patients who flared were rescued with open-label adalimumab. This study is registered with ClinicalTrials.gov, number NCT01808118.

FINDINGS

Between June 27, 2013, and October 22, 2015, 673 patients were enrolled to the study. The trial completed on April 14, 2017. Of 673 enrolled patients, 305 (45%) achieved sustained remission and were randomly assigned to double-blind treatment (152 patients to adalimumab and 153 to placebo). A greater proportion of patients continuing adalimumab than those receiving placebo did not experience a flare (107 [70%] of 152 patients vs 72 [47%] of 153 patients; p<0·0001) up to and including week 68. Among 673 patients receiving adalimumab at any time, 516 (77%) patients reported an adverse event and 28 (4%) experienced a serious adverse event. The most common adverse events in both the adalimumab and placebo groups were nasopharyngitis (25 [16%] vs 20 [13%]), upper respiratory tract infection (20 [13%] vs 12 [8%]), and worsening of axial spondyloarthritis (ten [7%] vs 21 [14%]).

INTERPRETATION

In patients with active non-radiographic axial spondyloarthritis who achieved sustained remission with adalimumab, continued therapy was associated with significantly fewer patients flaring than was treatment withdrawal.

FUNDING

AbbVie.

Measurement properties of the ASAS Health Index: results of a global study in patients with axial and peripheral spondyloarthritis

OBJECTIVES

To evaluate construct validity, interpretability, reliability and responsiveness as well as determination of cut-off points for good and poor health within the original English version and the 18 translations of the disease-specific Assessment of Spondyloarthritis international Society Health Index (ASAS HI) in 23 countries worldwide in patients with spondyloarthritis (SpA).

METHODS

A representative sample of patients with SpA fulfilling the ASAS classification criteria for axial (axSpA) or peripheral SpA was used. The construct validity of the ASAS HI was tested using Spearman correlation with several standard health outcomes for axSpA. Test-retest reliability was assessed by intraclass correlation coefficients (ICCs) in patients with stable disease (interval 4-7 days). In patients who required an escalation of therapy because of high disease activity, responsiveness was tested after 2-24weeks using standardised response mean (SRM).

RESULTS

Among the 1548 patients, 64.9% were men, with a mean (SD) age 42.0 (13.4) years. Construct validity ranged from low (age: 0.10) to high (Bath AnkylosingSpondylitisFunctioning Index: 0.71). Internal consistency was high (Cronbach's α of 0.93). The reliability among 578 patients was good (ICC=0.87 (95% CI 0.84 to 0.89)). Responsiveness among 246 patients was moderate-large (SRM=-0.44 for non-steroidal anti-inflammatory drugs, -0.69 for conventional synthetic disease-modifying antirheumatic drug and -0.85 for tumour necrosis factor inhibitor). The smallest detectable change was 3.0. Values ≤5.0 have balanced specificity to distinguish good health as opposed to moderate health, and values ≥12.0 are specific to represent poor health as opposed to moderate health.

CONCLUSIONS

The ASAS HI proved to be valid, reliable and responsive. It can be used to evaluate the impact of SpA and its treatment on functioning and health. Furthermore, comparison of disease impact between populations is possible.