Axial spondyloarthritis

Relationship between faecal calprotectin and inflammation in peripheral joints and entheses in axial spondyloarthritis

Objectives: To compare faecal calprotectin levels according to the type of manifestation and to investigate factors associated with increases in faecal calprotectin in patients with axial spondyloarthritis (axSpA). Method: The study enrolled 190 patients fulfilling the imaging arm of the Assessment of SpondyloArthritis international Society axSpA criteria. Faecal calprotectin levels were measured in an enzyme-linked immunosorbent assay. Systemic inflammatory markers and the Ankylosing Spondylitis Disease Activity Score (ASDAS) were also assessed. Peripheral joint involvement was assessed using the 44-joint examination and Spondyloarthritis Research Consortium of Canada Enthesitis Index. Results: Of 190 patients, 34 (18%) had increased faecal calprotectin levels. These patients were more likely to have ongoing peripheral arthritis and enthesitis (p = 0.016 and 0.001, respectively). A history of psoriasis and uveitis, or current uveitis symptoms, had no bearing on faecal calprotectin levels. Faecal calprotectin levels increased along with ASDAS-C-reactive protein (CRP), and correlated with ASDAS-erythrocyte sedimentation rate (ESR) (r = 0.240, p = 0.001), ASDAS-CRP (r = 0.162, p = 0.025), ESR (r = 0.228, p = 0.002), and CRP levels (0.258, p < 0.001). Tender joint and swollen joint counts also correlated with faecal calprotectin levels (r = 0.252 and 0.205, p < 0.001 and p = 0.005, respectively). Faecal calprotectin levels were higher in patients with current peripheral symptoms (p = 0.003). Peripheral symptoms were independently associated with increased faecal calprotectin levels (odds ratio = 4.083; 95% confidence interval 1.580-10.556). Conclusions: Faecal calprotectin levels in axSpA patients were associated with disease activity. Subclinical gut inflammation (assessed by measuring faecal calprotectin) in axSpA is more closely related to peripheral joint inflammation than to axial joint inflammation.

Copy number variation of IL17RA gene and its association with the ankylosing spondylitis risk in Iranian patients: a case-control study

Background

Ankylosing spondylitis (AS) is considered as a subtype of spondyloarthritis (SpA) that mainly leads to fatigue, stiffness, spinal ankylosis, and impaired physical functions with reduced quality of life. Interleukin (IL)-17A provokes additional inflammatory mediators and recruits immune cells to the inflamed site. IL17 expression increased in various inflammatory disorders including psoriasis, rheumatoid arthritis, multiple sclerosis, crohn’s disease, and ankylosing spondylitis. The current study aimed to evaluate the association of IL17RA copy number changes with the susceptibility to AS and their correlation to IL17RA expression in Iranian population.

Methods

IL17RA copy number genotyping assessments were carried out in 455 AS patients and 450 healthy controls, using custom TaqMan CNV assays. TaqMan primers and probe were located in Chr.22:17109553 based on pre-designed IL17RA Copy Number Assay ID, Hs02339506_cn. mRNA expression of IL17RA was also measured by SYBR Green real-time polymerase chain reaction (PCR).

Results

A IL17RA copy number loss (< 2) was associated with AS compared to 2 copies as reference (OR:2.18, 95% CI: (1.38–3.44), P-value < 0.001) and increased the risk of AS. IL17RA mRNA expression showed a significant increase in peripheral blood mononuclear cells (PBMCs) of all AS individuals than controls. The mRNA expression level of 2 copies was significantly higher in AS patients.

Conclusions

Our findings revealed that a low copy number of IL17RA might confer a susceptibility risk to AS. However, it is probably not directly involved in the regulation of IL17RA mRNA expression. Epigenetic mechanisms like DNA methylation, post-transcriptional, and -translational modifications that regulate the expression of the genes may contribute in upregulation of IL17RA mRNA expression in the loss of gene copy number condition.

Gender difference in ASAS HI among patients with ankylosing spondylitis

Objective

To assess the associations of the Assessment of Spondyloarthritis International Society Health Index (ASAS HI) with gender and other factors in patients with ankylosing spondylitis (AS).

Methods

From November 2017 to October 2018, we measured the Ankylosing Spondylitis Disease Activity Score (ASDAS), the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) and the ASAS HI score for AS patients at the Taichung Veterans General Hospital. After adjusting for disease activity (ASDAS-erythrocyte sedimentation rate [ESR], ASDAS- C-reactive protein [CRP], BASDAI+ESR or BASDAI+CRP), mSASSS and other potential confounders including medications, comorbidities, and laboratory data, any associations between gender and the sum score of ASDAS HI were assessed using multiple linear regression analysis, as well as any associations between gender and an ASAS HI score >5 using multivariable logistic regression analysis.

Results

A total of 307 AS patients (62 [20.2%] females, mean age 46.4 years [S.D. 13.3], mean symptom duration 20.6 years [S.D. 12.1]) were included. Multiple linear regression analysis showed that the male gender was significantly associated with a lower ASAS HI (B = -1. 91, 95% confidence interval [CI], −2.82–−1.00, p <0.001). Multivariable logistic regression analysis revealed that males also had a lower risk of achieving scores of ASAS HI > 5 than females (odds ratio = 0.15, 95% CI, 0.07–0.36, p <0.001). Disease activity measures, including ASDAS-ESR, ASDAS-CRP and BASDAI, had positive correlations with ASAS HI.

Conclusion

This single-center, cross-sectional study revealed that a higher ASAS HI score was significantly associated with female gender and higher disease activity measures.

A study of MRI-based radiomics biomarkers for sacroiliitis and spondyloarthritis

PURPOSE

To evaluate the performance of texture-based biomarkers by radiomic analysis using magnetic resonance imaging (MRI) of patients with sacroiliitis secondary to spondyloarthritis (SpA).

RELEVANCE

The determination of sacroiliac joints inflammatory activity supports the drug management in these diseases.

METHODS

Sacroiliac joints (SIJ) MRI examinations of 47 patients were evaluated. Thirty-seven patients had SpA diagnoses (27 axial SpA and ten peripheral SpA) which was established previously after clinical and laboratory follow-up. To perform the analysis, the SIJ MRI was first segmented and warped. Second, radiomics biomarkers were extracted from the warped MRI images for associative analysis with sacroiliitis and the SpA subtypes. Finally, statistical and machine learning methods were applied to assess the associations of the radiomics texture-based biomarkers with clinical outcomes.

RESULTS

All diagnostic performances obtained with individual or combined biomarkers reached areas under the receiver operating characteristic curves ≥ 0.80 regarding SpA related sacroiliitis and and SpA subtypes classification. Radiomics texture-based analysis showed significant differences between the positive and negative SpA groups and differentiated the axial and peripheral subtypes (P < 0.001). In addition, the radiomics analysis was also able to correctly identify the disease even in the absence of active inflammation.

CONCLUSION

We concluded that the application of the radiomic approach constitutes a potential noninvasive tool to aid the diagnosis of sacroiliitis and for SpA subclassifications based on MRI of sacroiliac joints.

Adequately dosed aerobic physical activity in people with axial spondyloarthritis: associations with physical therapy

INTRODUCTION

This study aimed to compare the engagement in moderate- and vigorous-intensity PA in axSpA patients with and without current physical therapy (PT).

METHODS

In this cross-sectional study, a survey, including current PT treatment (yes/no) and PA, using the 'Short QUestionnaire to ASsess Health-enhancing PA' (SQUASH), was sent to 458 axSpA patients from three Dutch hospitals. From the SQUASH, the proportions meeting aerobic PA recommendations (≥ 150 min/week moderate-, ≥ 75 min/week vigorous-intensity PA or equivalent combination; yes/no) were calculated. To investigate the association between PT treatment and meeting the PA recommendations, odds ratios (OR) with 95% confidence intervals (95% CI) were estimated using logistic regression models, adjusting for sex, age, health status and hospital.

RESULTS

The questionnaire was completed by 200 patients, of whom 68%, 50% and 82% met the moderate-, vigorous- or combined-intensity PA recommendations, respectively. Ninety-nine patients (50%) had PT treatment, and those patients were more likely to meet the moderate- (OR 2.09 [95% CI 1.09-3.99]) or combined-intensity (OR 3.35 [95% CI 1.38-8.13]) PA recommendations, but not the vigorous-intensity PA recommendation (OR 1.53 [95% CI 0.80-2.93]). Aerobic exercise was executed in 19% of individual PT programs.

CONCLUSION

AxSpA patients with PT were more likely to meet the moderate- and combined-intensity PA recommendations, whereas there was no difference in meeting the vigorous-intensity PA recommendation. Irrespective of having PT treatment, recommendations for vigorous-intensity PA are met by only half of the patients. Implementation should thus focus on aerobic PA in patients without PT and on vigorous-intensity PA in PT programs.

A novel privacy-preserving federated genome-wide association study framework and its application in identifying potential risk variants in ankylosing spondylitis

Genome-wide association studies (GWAS) have been widely used for identifying potential risk variants in various diseases. A statistically meaningful GWAS typically requires a large sample size to detect disease-associated single nucleotide polymorphisms (SNPs). However, a single institution usually only possesses a limited number of samples. Therefore, cross-institutional partnerships are required to increase sample size and statistical power. However, cross-institutional partnerships offer significant challenges, a major one being data privacy. For example, the privacy awareness of people, the impact of data privacy leakages and the privacy-related risks are becoming increasingly important, while there is no de-identification standard available to safeguard genomic data sharing. In this paper, we introduce a novel privacy-preserving federated GWAS framework (iPRIVATES). Equipped with privacy-preserving federated analysis, iPRIVATES enables multiple institutions to jointly perform GWAS analysis without leaking patient-level genotyping data. Only aggregated local statistics are exchanged within the study network. In addition, we evaluate the performance of iPRIVATES through both simulated data and a real-world application for identifying potential risk variants in ankylosing spondylitis (AS). The experimental results showed that the strongest signal of AS-associated SNPs reside mostly around the human leukocyte antigen (HLA) regions. The proposed iPRIVATES framework achieved equivalent results as traditional centralized implementation, demonstrating its great potential in driving collaborative genomic research for different diseases while preserving data privacy.

Elevated tenascin-C serum levels in patients with axial spondyloarthritis

This study aimed to examine serum tenascin C (TNC) in different subsets of axial spondyloarthritis (axSpA) patients. Sixty-one patients fulfilling the Assessment of SpondyloArthritis international Society classification criteria for axSpA and 20 healthy subjects (HS) were included in study. Based on imaging, patients were classified as non-radiographic (n=16) and radiographic (n=45) axSpA. TNC serum levels were determined by ELISA. Disease-related factors including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and C-reactive protein (CRP) levels were determined. TNC levels were elevated in axSpA patients [535.3 (457.7–677.2) ng/ml] compared to HS [432.1 (329.1–565.9) ng/ml, p=0.007]. Dividing axSpA into radiographic and non-radiographic subsets, the difference in TNC was observed between the radiographic subset and HS [535.3 (434.5–677.2) vs. 432.1 (329.1–565.9) ng/ml, p=0.022]. TNC levels did not correlate with disease activity measures (serum CRP or BASDAI). Nevertheless, the weak correlation of TNC levels with different disease stages (r=0.25, p=0.025) was found, with the highest levels in patients with syndesmophytes. TNC levels are elevated across various subsets of axSpA, and although not related to systemic disease activity, TNC levels might reflect chronic structural spinal changes in axSpA patients. However, its specific role in bone metabolism should be elucidated in further studies.

An update on serum biomarkers to assess axial spondyloarthritis and to guide treatment decision

Axial spondyloarthritis (axSpA) is a group of debilitating, chronic, rheumatic conditions characterized by inflammation and new bone formation, mainly involving the spine and the sacroiliac joints. The lack of biomarkers in axSpA is well known. Despite significant treatment advances in recent years thanks to the introduction of drugs with a new mode of action, such as new biologic and targeted synthetic disease-modifying antirheumatic drugs, no relevant improvement in the identification of disease biomarkers has been achieved. Common parameters, such as erythrocyte sedimentation rate and C-reactive protein, which are routinely used to measure systemic inflammation, are the sole markers available to date and are not adequate to assess disease activity in all patients. The aim of this study is to review the most promising serum biomarkers that may help treatment decision in axSpA via a proper assessment of disease activity and identification of negative prognostic factors.

Risk of Malignancy in Spondyloarthritis: A Systematic Review

Systematic inflammatory diseases, including rheumatoid arthritis (RA), are associated with an increased risk of malignancies. However, the pathogenesis of spondyloarthritis (SpA), which includes both ankylosing spondylitis and psoriatic arthritis, is different from RA, and the risk of malignancy and sites involved may also be different. It is important to better understand associations of SpA with site-specific cancers to facilitate appropriate cancer screening. The goal of this review was to examine the association of SpA with malignancy and the potential impact of therapy for SpA on development of malignancy.

Prevalence of ankylosing spondylitis in a Chinese population: a systematic review and meta-analysis

Ankylosing spondylitis (AS) is a common inflammatory rheumatic disease that affects the axial skeleton. In this study, we systematically reviewed Chinese AS epidemiological studies from the past 15 years to elucidate its prevalence and provide scientific data for China's health care system. AS epidemiological research in China was summarized by conducting a literature review. A review and statistical analysis of the literature on the epidemiology of AS in mainland China published from May 2005 to May 2019 were performed via a meta-analysis. We calculated the prevalence of AS and analysed differences by sex, region, and population source using STATA12.0 software. Eleven papers including 122,558 subjects from mainland China were included. Over the past 15 years, the total prevalence of AS in mainland China was 0.29% (95% CI 0.22-0.35%), ranging from 0.42% (95% CI 0.31-0.52%) in males to 0.15% (95% CI 0.13-0.18%) in females; the difference in the prevalence of AS by sex was statistically significant (P < 0.001). The prevalence of AS in both southern and northern China was 0.31% (95% CI 0.21-0.42% and 0.21-0.40%, respectively), with no significant difference noted (P = 0.816 > 0.005). The prevalence of AS in Chinese military populations was 0.27% (95% CI 0.09-0.45%), and in community populations, it was 0.29% (95% CI 0.23-0.35%). There was no statistically significant difference in the prevalence of AS by sampling resource (P = 0.115 > 0.005). The prevalence of AS in China was 0.29% and continues to increase. Sex differences in its prevalence were identified; the prevalence rate was 2.8 times higher in males than in females. Epidemiologists in China should formulate precise scientific investigations to provide additional authoritative epidemiological data for the prevention and treatment of AS.

Mud-bath treatment of seronegative spondyloarthritis: experience at the Euganean Thermal Area

Mud-bath therapy (MBT) has been used as a treatment for rheumatic diseases and musculoskeletal complaints in the Euganean Thermal Area (near Padova, Italy) since ancient time. There is no consensus about the use of MBT in patients with inflammatory rheumatic diseases, although experimental studies have suggested a beneficial effect of MBT on chronic articular inflammation. To evaluate the effects of MBT in patients affected by seronegative spondyloarthritis, very common chronic inflammatory rheumatic diseases, randomized controlled trials (RCT) performed in the Euganean Thermal Area have been reviewed. A significant improvement of spondylitis parameters was observed in enteropathic spondylitis, without bowel symptom exacerbation. A long-term amelioration of clinical evaluation indices was found in ankylosing spondylitis. A significant improvement of cutaneous lesions, arthritis activity, and patient's functional ability was observed in psoriatic arthritis. MBT was usually well tolerated and adverse side effects were rarely reported. The review of the RCT suggests that MBT may exert additional beneficial effects in patients with seronegative spondyloarthritis treated with pharmacological therapy.

Comparison of the Efficacy and Safety of Adalimumab (Humira) and the Adalimumab Biosimilar Candidate (HS016) in Chinese Patients with Active Ankylosing Spondylitis: A Multicenter, Randomized, Double-Blind, Parallel, Phase III Clinical Trial

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of the biosimilar candidate of adalimumab (HS016) compared with adalimumab (Humira) for the treatment of active ankylosing spondylitis.

METHODS

A multicenter, randomized, double-blind, parallel, positive control, phase III clinical trial was conducted at 28 locations in China. Patients with active ankylosing spondylitis were randomized in a 2:1 ratio to subcutaneously receive 40 mg of either HS016 or adalimumab every other week for 24 weeks. The primary endpoint was to achieve at least a 20% improvement (ASAS20) in patients at 24 weeks according to the Assessment of Spondyloarthritis International Society criteria. The secondary endpoint included other efficacy assessment parameters, health evaluations, safety, pharmacokinetic, and immunogenicity parameters.

RESULTS

Following the random assignment of 648 patients into HS016 (n = 416) and adalimumab (n = 232) groups, no significant difference was found in the ASAS20 response rates at 24 weeks between the HS016 (364/416, 87.5%) and adalimumab (209/232, 90.1%) treatments and the difference between the response rates (- 2.59%; 90% confidence interval [CI] - 6.77 to 1.60) was within the predefined equivalence margin (± 15%). There were also no significant differences when the secondary endpoints were compared (all p > 0.05). Similarly, the rates of treatment-emergent adverse events (TEAEs) were not significantly different between the two groups, with most TEAEs being mild to moderate. Only nine severe cases were found, including seven within the HS016 group, three (0.7%) of which were tuberculosis cases. Plasma concentrations of HS016 and adalimumab from weeks 12 to 14 were similar during the steady-state period and steady-state maximal concentration (Cmax,ss) was equivalent for HS016 (7356.6 ng/mL) and adalimumab (7600.3 ng/mL). The accumulated proportion of patients with positive human anti-human antibodies (HAHAs) at week 24 was 326/412 (79.1%) in the HS016 group and 183/229 (79.9%) in the adalimumab group (p > 0.05), while the accumulated proportion of patients with positive neutralizing antibody (NAb) tests were 72/412 (17.5%) in the HS016 group and 43/229 (18.8%) in the adalimumab group (p > 0.05).

CONCLUSION

HS016 resembled adalimumab in efficacy and safety over the 24-week treatment period.

TRIAL REGISTRATION NUMBER

ChiCTR1900022520.

Early recognition of patients with axial spondyloarthritis—evaluation of referral strategies in primary care

Objective

Chronic inflammatory back pain (IBP) is frequently reported in axial SpA (axSpA) but also in the general population. We evaluated a recently proposed two-step referral system for early recognition of axSpA in primary care and compare it with other combinations of symptoms and SpA-related items.

Methods

Consecutive chronic back pain patients ≤45 years of age answered a questionnaire and were seen by a primary care physician who decided whether HLA-B27 needed to be determined. They were then referred to a rheumatologist who made the diagnosis. Generally sticking to the two-step system with HLA-B27 as an additional option, combinations with a sensitivity ≥90% and a likelihood ratio &gt;4 were compared.

Results

A total of 326 patients were included, 46 of whom were diagnosed with axSpA (14.1%). The sensitivity of the strategy was 87%, the specificity was 56.8% and the positive and negative predictive values were 24.8% and 96.4%, respectively. A ‘good response to NSAIDs’, ‘morning stiffness &gt;30 min’ and ‘elevated C-reactive protein’ performed best, with a sensitivity of 91%, specificity of 67%, positive predictive value of 31% and negative predictive value of 98%. On that basis, only three patients had to be seen by a rheumatologist to diagnose one.

Conclusion

The earlier proposed referral system worked well but was outperformed by other combinations with high sensitivity and better specificity, which deserve to be prospectively studied.

Understanding differences between men and women with axial spondyloarthritis

Axial spondyloarthritis (axSpA) is a chronic inflammatory immune-mediated disease resulting in inflammatory low back pain and other inflammatory manifestations in peripheral joints and entheses. AxSpA encompasses both ankylosing spondylitis (AS), in which patients present with definitive sacroiliitis visible on radiographic imaging, as well as nonradiographic axSpA (nr-axSpA), in which such changes may not be discernable. Emerging evidence suggests that women and men experience axSpA differently. Although the prevalence of AS is approximately 2- to 3- fold higher in men than in women, nr-axSpA occurs with roughly equal frequency in women and men. The goal of this review is to increase awareness of sex differences in axSpA by exploring the distinct manifestations of disease and disease characteristics in women, the overall clinical burden, recommendations for diagnosis, and potential treatment options. We summarize and contextualize the results of recent studies that illuminate sex differences in nr-axSpA and AS, including differences in disease manifestation and progression. It is important that sex differences in axSpA are understood and considered when diagnosing and treating the spectrum of axSpA, including AS and nr-axSpA.

Spine and Sacroiliac Joints Lesions on Magnetic Resonance Imaging in Early Axial-Spondyloarthritis During 24-Months Follow-Up (Italian Arm of SPACE Study)

Objectives: Our study aimed to identify: (1) the prevalence of spine and pelvis magnetic resonance imaging (MRI-spine and MRI-SIJ) inflammatory and structural lesions in patients (pts) with a diagnosis of axial spondyloarthritis (axSpA); (2) the predictive factors for a severe disease pattern with a higher probability of radiographic progression. Materials and Methods: Seventy-five pts with low back pain (LBP) (≥3 months, ≤2 years, onset ≤45 years) underwent physical examination, questionnaires, laboratory tests, X-rays, MRI-spine, and MRI-SIJ at baseline (T0) and during a 24-months follow-up. Two expert rheumatologists made axSpA diagnosis and classification (according ASAS criteria). MRI-spine, MRI-SIJ and X-rays were scored independently by 2 readers following the SPARCC, mSASSS, and mNY-criteria. According to ASAS criteria, 21 pts fulfilled imaging arm only and 29 clinical arm with/without imaging arm; 25 pts did not fulfill ASAS criteria. Results: At T0 the mean ± SD LBP onset was 28.51 ± 8.05 years, 45.3% pts were male, 38.7% were HLA-B27+; 56% showed bone marrow oedema (BMO) at MRI-spine and 64% at MRI-SIJ. Signs of enthesitis were found in 58% pts in the thoracic spine. Eighteen (24%) pts presented BMO at MRI-spine with a negative MRI-SIJ. The prevalence of BMO lesions and the SPARCC SIJ and spine score decreased during the follow-up in the 2 cohorts meeting ASAS criteria. An early onset of LBP, a lower use of NSAIDs, a BASDAI>4 were identified as predictors of spine structural damage; the high SPARCC SIJ score appeared to be a predictor of SIJ structural damage. A higher mSASSS was predicted by a lower age of onset of LBP. Predictor of higher SPARCC spine was a higher NSAIDs and of higher SPARCC SIJ score the HLA-B27 positivity with increased inflammatory biomarkers. Conclusions: At T0 a significant prevalence of BMO lesions was observed both in SIJ and spine, with predominant involvement of thoracic district. Since positive MRI-spine images were observed in the absence of sacroiliitis, these findings seem to be relevant in the axSpA diagnosis. Early age of disease onset, long duration of LBP, increased inflammatory biomarkers, higher use of NSAIDs, male gender, HLA-B27 positivity, SPARCC SIJ score>2 appeared predictors of radiological damage and activity.

Does Belonging to a Patient Association Is of Help for Patients with Axial Spondyloarthritis? Results from the Atlas Survey

PURPOSE OF REVIEW

International guidelines for axial spondyloarthritis (axSpA) suggest that patients benefit from becoming members of patient associations. However, the scientific evidence for this is limited and unconvincing. The objective of this study was to evaluate the differences in sociodemographic characteristics, lifestyle habits, and patient-reported outcomes (PROs) between axSpA patients belonging to patient associations versus those who do not.

RECENT FINDINGS

Out of 680 patients, 301 (44.3%) were members of a patient association. A significant proportion of association members were found to engage in physical activities considered appropriate to their condition (48.2% vs. 39.8%, p = 0.03), and smoked significantly less compared with their non-association counterparts (22.7% vs. 33.6%, p = 0.02). In addition, despite having longer disease duration, and receiving similar treatments, members of associations reported significantly lower disease activity (BASDAI 5.1 vs. 5.8; p < 0.001), less functional limitations (Functional Limitation Index 26.4 vs. 28.6; p < 0.05), and a lower risk of psychological distress (GHQ-12 4.9 vs. 6.5; p < 0.001). The results of this study suggest there are beneficial effects of belonging to a patient association for managing axSpA, since those member patients experience better lifestyle habits and PROs than those who do not so participate. Rheumatologists should encourage patients to enroll in patient associations for a holistic approach to managing their condition.

Efficacy and Safety of Sinomenine Preparation for Ankylosing Spondylitis: A Systematic Review and Meta-Analysis of Clinical Randomized Controlled Trials

OBJECTIVES

To systematically evaluate the efficacy and safety of sinomenine preparation (SP) for treating ankylosing spondylitis (AS).

METHODS

Clinical randomized controlled trials (RCTs) of SP for treating AS were systematically identified in six electronic databases including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP), and Wanfang Databases from the inception up to 31 October 2019. Cochrane's risk of bias tool was used to assess the methodological quality and Review Manager 5.3 software was used to analyze data.

RESULTS

A total of 12 RCTs involving 835 patients were finally included. According to interventions, RCTs were divided into two types. The intervention in 10 RCTs was SP combined with conventional pharmacotherapy (CPT) versus CPT and that in 2 RCTs was SP alone versus CPT. The results of the meta-analysis showed that, compared with CPT alone, SP combined with oral CPT has better improvement in BASDAI (WMD = -1.84, 95% CI [-3.31, -0.37], P=0.01), morning stiffness time (WMD = -13.46, 95% CI [-16.12, -10.79], P < 0.00001), the Schober test (WMD = 1.26, 95% CI [0.72, 1.80], P < 0.00001), the occipital wall test (WMD = -0.55, 95% CI [-0.96, -0.14], P=0.009), the finger-to-ground distance (WMD = -3.28, 95% CI [-5.64, -0.93], P=0.006), 15 m walking time (WMD = -8.81, 95% CI [-13.42, -4.20], P=0.0002), the C-reactive protein (CRP) (WMD = -1.84, 95% CI [-3.24, -0.45], P=0.01), and the total effective rate (RR = 1.10, 95% CI [1.01, 1.20], P=0.03). Besides, it also showed that oral SP alone may be more effective in improving morning stiffness time (WMD = -31.89, 95% CI [-34.91, -28.87], P < 0.00001) compared with CPT alone. However, this study cannot provide evidence that loading the injectable SP based on CPT can significantly increase the efficacy due to the insufficient number of studies included. In terms of adverse events, there was no statistically significant difference between the experimental group and the control group.

CONCLUSIONS

This study shows that oral SP may be effective and safe in the treatment of AS. Due to the low methodological quality of the included RCTs and the limitations of the meta-analysis, it is still necessary to carry out more multicenter, large-sample, and high-quality RCTs to further verify the conclusions. The review protocol was registered on PROSPERO (CRD42018099170), and the review was constructed following the PRISMA guidelines (Annex 1).

Efficacy and safety of IL-17 inhibitors for the treatment of ankylosing spondylitis: a systematic review and meta-analysis

Objectives

To systematically assess the efficacy and safety of IL-17 inhibitors in patients with active ankylosing spondylitis.

Methods

A systematic review of the literature was performed for randomized controlled trials (RCTs) concerning IL-17 inhibitors in patients with ankylosing spondylitis. Meta-analyses were used to determine the efficacy and safety of the IL-17 inhibitors in the treatment of these patients. The primary endpoint was predefined as the proportion of patients with at least 20% improvement in the Assessment of Spondyloarthritis International Society (ASAS20) response criteria at week 16, and the secondary endpoint was defined as ASAS40 at week 16.

Results

Six phase III randomized, double-blind, placebo-controlled trials including 1733 patients (1153 patients received IL-17 inhibitors, including secukinumab or ixekizumab, whereas 580 patients received a placebo as comparators) were included. At week 16, the IL-17 inhibitor regimen produced a significant increase in the ASAS20 response rate (RR = 1.63, 95% CI 1.45 to 1.84, p = 0.00) and the secondary endpoint ASAS40 response rate (RR = 2.12, 95% CI 1.75 to 2.56, p = 0.00) versus those for the placebo. With respect to the safety profile, more treatment-emergent adverse events (RR = 1.11, 95% CI 1.01 to 1.22, p = 0.03) and non-severe infections (RR = 1.82, 95% CI 1.40 to 2.37, p < 0.001) were described after treatment with IL-17 inhibitors than after treatment with placebo, while no increased risk of other adverse events was indicated after IL-17 inhibitor therapy, including death, discontinuation due to adverse events, or serious adverse events.

Conclusions

IL-17 inhibitors produced favorable response rates but an increased risk of non-severe infections in the treatment of active ankylosing spondylitis.

Maintenance of clinical remission in early axial spondyloarthritis following certolizumab pegol dose reduction

Background

The best strategy for maintaining clinical remission in patients with axial spondyloarthritis (axSpA) has not been defined. C-OPTIMISE compared dose continuation, reduction and withdrawal of the tumour necrosis factor inhibitor certolizumab pegol (CZP) following achievement of sustained remission in patients with early axSpA.

Methods

C-OPTIMISE was a two-part, multicentre phase 3b study in adults with early active axSpA (radiographic or non-radiographic). During the 48-week open-label induction period, patients received CZP 200 mg every 2 weeks (Q2W). At Week 48, patients in sustained remission (Ankylosing Spondylitis Disease Activity Score (ASDAS) <1.3 at Weeks 32/36 and 48) were randomised to double-blind CZP 200 mg Q2W (full maintenance dose), CZP 200 mg every 4 weeks (Q4W; reduced maintenance dose) or placebo (withdrawal) for a further 48 weeks. The primary endpoint was remaining flare-free (flare: ASDAS ≥2.1 at two consecutive visits or ASDAS >3.5 at any time point) during the double-blind period.

Results

At Week 48, 43.9% (323/736) patients achieved sustained remission, of whom 313 were randomised to CZP full maintenance dose, CZP reduced maintenance dose or placebo. During Weeks 48 to 96, 83.7% (87/104), 79.0% (83/105) and 20.2% (21/104) of patients receiving the full maintenance dose, reduced maintenance dose or placebo, respectively, were flare-free (p<0.001 vs placebo in both CZP groups). Responses in radiographic and non-radiographic axSpA patients were comparable.

Conclusions

Patients with early axSpA who achieve sustained remission at 48 weeks can reduce their CZP maintenance dose; however, treatment should not be completely discontinued due to the high risk of flare following CZP withdrawal.

Trial registration number

NCT02505542, ClinicalTrials.gov.

High-Intensity Exercise Improves Fatigue, Sleep, and Mood in Patients With Axial Spondyloarthritis: Secondary Analysis of a Randomized Controlled Trial

OBJECTIVE

Although exercise is recommended in the treatment of axial spondyloarthritis (axSpa), the focus has been on flexibility, and the effect of high-intensity exercises is unknown. The purpose of this study was to investigate the effect of high-intensity exercises on fatigue, sleep, and mood in patients with axSpA.

METHODS

In this secondary analysis of a randomized controlled trial, participants were recruited from outpatient clinics at 4 hospitals in Scandinavia. A total of 100 patients with axSpA were randomized to either an exercise group (n = 50) or a control group (n = 50). High-intensity exercise was provided 3 times per week for 3 months and supervised by a physical therapist. The controls received no intervention. Measurements were self-reported at baseline, 3 months, and 12 months: fatigue, using the Fatigue Severity Scale (range = 0-7, 7 = worst, ≥5 = severe); vitality, using the RAND 36-item short-form health survey (SF-36, range = 0-100, 100 = best); sleep, using the Pittsburgh Sleep Quality Index (range = 0-21, 21 = worst, >5 = poor quality); mood, using the General Health Questionnaire 12 (range = 0-36, 36 = worst); and general health, using the EUROQoL (range = 0-100, 100 = best).

RESULTS

A total of 38 participants (76%) in the exercise group followed ≥80% of the exercise protocol. At 3 months, there was a significant beneficial effect on fatigue (mean group differences = -0.4, 95% CI = -0.7 to -0.1), vitality (5.0, 95% CI = 1.1 to 10.5), mood (-2, 95% CI = -3.7 to -0.04), and general health (9.0, 95% CI = 3.3 to 14.7) but no effect on sleep (-1.1, 95% CI = -2.1 to 0.2). Compared with the control group, the exercise group had a reduced rate of severe fatigue and poor sleep. No differences were seen between the groups at 12 months.

CONCLUSIONS

A 3-month exercise program had a beneficial effect on fatigue, sleep, mood, and general health in patients with axSpA at the end of the intervention; however, no long-term effects were seen.

IMPACT

High-intensity cardiorespiratory and strength exercises should be considered as important in exercise programs for patients with axSpA.

Mimics of axial spondyloarthritis

PURPOSE OF REVIEW

Axial spondyloarthritis (AxSpA) is a distinct clinical entity with characteristic clinical and radiographic features; however, a multitude of other metabolic, infectious and inflammatory disorders mimic it both clinically and radiographically.

RECENT FINDINGS

We present in this review article recent updates about the various disease entities and conditions that may mimic AxSpA and how to differentiate among them. The sensitivity and specificity of MRI in diagnosing AxSpA has limitations and needs to be interpreted in the context of the clinical picture. Interestingly, some recent studies have highlighted that a relatively high prevalence of bone marrow edema on pelvic MRIs in healthy volunteers which could even be categorized as having a 'positive MRI' as defined by Assessment of Spondyloarthritis International Society. Another study revealed that a substantial proportion of patients with suspected sacroiliitis were more commonly diagnosed with diseases other than inflammatory sacroiliitis. On the basis of these reports, it is prudent to request MRIs in the appropriate clinical context and interpreted with caution taking into considerations the wide differential diagnosis of such MRI changes.

SUMMARY

Highlighting the clinical pearls that differentiate disorders suspected of having sacroiliitis will lead to earlier and correct diagnosis and management; however, one must always take into considerations the radiographic and MRI findings in addition to the clinical presentations in order to make the appropriate diagnosis.

Efficacy of needle-knife combined with etanercept treatment regarding disease activity and hip joint function in ankylosing spondylitis patients with hip joint involvement: A randomized controlled study

This study aimed to assess the efficacy of needle-knife (NK) combined with etanercept (NKCE) in attenuating pain, inflammation, disease activity, and improving hip joint function in ankylosing spondylitis (AS) patients with hip joint involvement.Totally, 90 patients with active AS involving unilateral hip joint were enrolled and randomly assigned in 1:1:1 ratio to receive NKCE, NK or conventional drugs (control). The ESR, CRP, hip joint pain Visual Analogue Scale (VAS) score, bath ankylosing spondylitis disease activity index (BASDAI), bath ankylosing spondylitis functional index (BASFI), modified Harris hip score (mHHS), and range of motion (ROM) of affected hip joint were assessed at baseline (W0), after 1-week treatment (W1) and after 24-week treatment (W24).ESR and CRP were decreased in NKCE group compared with NK and control groups, while was not attenuated in NK group compared with control group. Regrading pain and disease activity, NKCE group presented a reduction in hip pain VAS score and BASDAI compared with NK and control groups, and NK group showed a decrease in hip pain VAS score and BASDAI compared with control group. Besides, BASFI was lowered in NKCE and NK groups compared with control group, but similar between NKCE and NK groups. mHHS and hip ROM were raised in NKCE and NK groups compared with control group, but similar between NKCE and NK groups.NKCE decreases hip pain, inflammation, disease activity and improves hip joint function in AS patients with hip joint involvement.

Retinal and choroidal vascular structures are affected in axial spondyloarthritis: an optical coherence tomography study

PURPOSE

The aim of this study is to evaluate the retinal and choroidal structures in r- and nr-axSpA patients using spectral domain optical coherence tomography (SD-OCT) and to compare changes with healthy controls.

METHODS

In this cross-sectional study, 70 axSpA patients (50 radiographic- and 20 nr-axSpA) and 50 healthy control subjects were included. Choroidal thickness (ChT), macular thickness, retinal nerve fiber layer (RNFL), and the ganglion cell complex (GCC) were measured by SD-OCT. For ChT values, seven lines at nasal and temporal were drawn at 500-μm intervals, centering the subfoveal sclerochoroidal junction. Analysis of the data was performed with the SPSS program. Mann-Whitney U test was performed for comparison of non-normally distributed continuous data; Student's t test was used for normal distributed data.

RESULTS

No significant difference was observed between 70 (66% male; mean age 39.7 ± 10.4 years) axSpA patients (50 radiographic and 20 nr-axSpA) and 50 (mean age 41.2 ± 6.2 years) healthy control subjects (p 0.417). R-axSpA and nr-axSpA groups and control group were similar in terms of spherical equivalent, intraocular pressure, axial length, and body mass index (p 0.574, p 0.874, p 0.918, p 0.344, respectively). While mean macular and GCC thicknesses were significantly lower in the patient group than in the healthy group, there was no significant difference between the two groups in terms of RNFL thickness.

CONCLUSION

The present study showed that there was no significant relationship between markers and scores indicating disease activity and ChT, MT, RNFL, and GCC thicknesses. However, an increase in choroidal thickness and involvement of the retinal layers has also been demonstrated in patients with spondyloarthritis. In addition, the relationship between disease activity and retinal layer involvement is remarkable in the r-axSpA group.

Responsiveness and Interpretability of 2 Measures of Physical Function in Patients With Spondyloarthritis

BACKGROUND

Maintenance or improvement of physical function is an important treatment target in the management of patients with axial spondyloarthritis (axSpA); measurement tools that can detect changes in physical function are therefore important.

OBJECTIVES

The objective of this study was to compare responsiveness and interpretability of the patient-reported Bath Ankylosing Spondylitis Functional Index (BASFI) and the Ankylosing Spondylitis Performed-Based Improvement (ASPI) in measuring change in physical function after exercise in patients with axSpA.

DESIGN

This was a sub-study of 58 patients nested within a randomized controlled trial comparing the effect of 12 weeks of exercise with usual care.

METHODS

Responsiveness and interpretability were assessed according to the Consensus-based Standards for the selection of health status Measurement Instrument. Responsiveness was assessed by testing 8 predefined hypotheses for ASPI and BASFI. Interpretability was assessed by: (1) using patients' reported change as an anchor ("a little better" = minimal important change) and (2) by categorizing patients with a 20% improvement as responders.

RESULTS

For ASPI and BASFI, 5 of 8 (63%) versus 2 of 8 (25%) of the predefined hypotheses for responsiveness were confirmed. The minimal important change values for improvement in physical function were 3.7 seconds in ASPI and 0.8 points (on a scale from 0 to 10) for BASFI. In the intervention group, 21 of 30 (70%) and 13 of 30 (43%) of the patients were categorized as responders measured with ASPI and BASFI, respectively. There was a tendency towards a floor effect in BASFI, as 8 of 58 (14%) patients scored the lowest value at baseline.

LIMITATIONS

This study was limited by its moderate sample size.

CONCLUSIONS

Our findings suggest that ASPI is preferable over BASFI when evaluating physical function after exercise interventions in patients with axSpA.

Therapeutic Potential of Ixekizumab in the Treatment of Ankylosing Spondylitis: A Review on the Emerging Clinical Data

Over the last 20 years, the greatly improved knowledges of underlying pathogenic mechanisms of AS, including the role of tumor necrosis factor (TNF), the interleukin 23/Th17 axis, and interleukin-17 (Il-17), constituted the rationale to develop biologics selectively inhibiting these pathways. For more than 10 years, anti-TNF biologics were successfully employed to treat AS, with marked improvement of signs and symptoms in around 60% of the patients. Recent knowledge of the pathophysiology of spondyloarthritis has highlighted the emerging role of the IL-17/IL-23 axis. New therapies with selective biological drugs have emerged in the treatment of this pathology. In this review, we evaluated the effects of ixekizumab, a new anti–IL-17A, that was licensed both by EMA and FDA in August 2019 for the treatment of ankylosing spondylitis. The review highlights the efficacy and safety data of the 3 randomized controlled trials (COAST V-COAST W-COAST X) and those of the extension to 52 weeks of COAST V and COAST W.

Histographic analysis of oedema and fat in inflamed bone marrow based on quantitative MRI

Objective

To demonstrate proof-of-concept for a quantitative MRI method using histographic analysis to assess bone marrow oedema and fat metaplasia in the sacroiliac joints.

Materials and methods

Fifty-three adolescents aged 12–23 with known or suspected sacroiliitis were prospectively recruited and underwent quantitative MRI (qMRI) scans, consisting of chemical shift-encoded (at 3 T) and diffusion-weighted imaging (at 1.5 T), plus conventional MRI (at 1.5 T) and clinical assessment. qMRI scans produced proton-density fat fraction (PDFF) and apparent diffusion coefficient (ADC) maps of the sacroiliac joints (SIJs), which were analysed using an in-house software tool enabling partially automated ROI definition and histographic analysis. Logistic regression and receiver operating characteristic (ROC) analyses assessed the predictive performance of ADC- and PDFF-based parameters in identifying active inflammation (oedema) and structural damage (fat metaplasia).

Results

ADC-based parameters were associated with increased odds of oedema (all p < 0.05); ROC-AUC was higher for histographic parameters representing the upper end of the ADC distribution than for simple averages. Similarly, PDFF-based parameters were associated with increased odds of fat metaplasia (all p < 0.05); ROC area-under-the-curve was higher for histographic parameters representing the upper end of the PDFF distribution than for simple averages. Both ADC- and PDFF-based histographic parameters demonstrated excellent inter- and intra-observer agreement (ICC > 0.9).

Conclusions

ADC-based parameters can differentiate patients with bone marrow oedema from those without, whilst PDFF-based parameters can differentiate patients with fat metaplasia from those without. Histographic analysis might improve performance compared with simple averages such as the mean and median and offers excellent agreement within and between observers.

Key Points

• Quantitative MRI with histographic analysis can identify bone marrow oedema (an active inflammatory lesion) and fat metaplasia (a ‘chronic’ inflammatory lesion) in patients with spondyloarthritis.

• The use of histographic analysis might improve the performance of quantitative MRI for detecting bone marrow oedema and fat metaplasia compared with simple averages such as the mean and median.

• Bone marrow oedema and fat metaplasia are known to be of diagnostic and prognostic significance, and the proposed method could support clinical decisions around biologic (and other) therapies in spondyloarthritis.

Electronic supplementary material

The online version of this article (10.1007/s00330-020-06785-x) contains supplementary material, which is available to authorized users.

Performance of magnetic resonance imaging in the diagnosis of axial spondyloarthritis: a systematic literature review

OBJECTIVES

To summarize the evidence on the performance of MRI for the diagnosis of axial SpA.

METHODS

This was a systematic literature review of all studies from January 2013 to March 2017 including adult patients with clinically suspected axial SpA undergoing MRI. Studies from a previously published systematic literature review up to January 2013 were also included.

RESULTS

Thirty-one studies were included. Six studies demonstrated good sensitivity and specificity for SI joint (SIJ) bone marrow oedema (BMO). Specificity was increased by the presence of other structural lesions alongside BMO, particularly erosions or fat infiltration. Four studies addressed the utility of SIJ fat infiltration, finding good sensitivity but poor specificity. SIJ erosions showed good specificity in five studies. Studies addressing high T1 signal in the SIJ, fluid signal in the SIJ, ankylosis, sclerosis, capsulitis, backfill and vacuum phenomenon reported limited diagnostic value. In the spine, four studies reported moderate sensitivity and specificity for corner inflammatory lesions, and four reported poor sensitivity and specificity for spinal fat infiltration. Five studies evaluated the added value of spinal MRI over SIJ MRI alone, with variable results depending on the cohort. Six studies addressed the effect of acquisition parameters on diagnostic accuracy: fat-saturated T2-weighted imaging and short tau inversion recovery (STIR) imaging showed comparable utility in identifying BMO. Three studies showed that gadolinium was of minimal added value in the detection of BMO.

CONCLUSIONS

These results confirmed the diagnostic utility of MRI in axial SpA. Performance varied according to the characteristics of the cohort and the number and combination of MRI lesions considered.

Comparison of comorbidities and treatment between ankylosing spondylitis and non-radiographic axial spondyloarthritis in the United States

OBJECTIVES

This study aimed to compare comorbidities and biologic DMARD (bDMARD) use between AS and non-radiographic axial SpA (nr-axSpA) patients, using a large cohort of patients from routine clinical practice in the United States.

METHODS

We performed a cross-sectional study using electronic medical records from two academic hospitals in the United States. Data were extracted using automated searches (⩾3 ICD codes combined with text searches) and supplemented with manual chart review. Patients were categorized into AS or nr-axSpA according to classification criteria. Disease features, comorbidities (from a list of 39 chronic conditions) and history of bDMARD prescription were compared using descriptive statistics.

RESULTS

Among 965 patients identified, 775 (80%) were classified as having axSpA. The cohort was predominantly male (74%) with a mean age of 52.5 years (s.d. 16.8). AS patients were significantly older (54 vs 46 years), more frequently male (77% vs 64%) and had higher serum inflammatory markers than those with nr-axSpA (median CRP 3.4 vs 2.2 mg/dl). Half of all patients had at least one comorbidity. The mean number of comorbidities was 1.5 (s.d. 2.2) and similar between AS and nr-axSpA groups. A history of bDMARD-use was seen in 55% of patients with no difference between groups. The most commonly prescribed bDMARDs were adalimumab (31%) and etanercept (29%). Ever-prescriptions of individual bDMARDs were similar between AS and nr-axSpA.

CONCLUSION

Despite age differences, nr-axSpA patients had similar comorbidity burdens as those with AS. Both groups received comparable bDMARD treatment in this United States clinic-based cohort.

Indirect comparison of NSAIDs for ankylosing spondylitis: Network meta-analysis of randomized, double-blinded, controlled trials

Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by lower back pain, enthesitis and asymmetrical peripheral arthritis. Non-steroidal anti-inflammatory drugs (NSAIDs) are recommended as a first-line drug treatment for AS. The aim of the present study was to evaluate the efficacy and safety of NSAIDs in patients with active AS. A total of 9 randomized controlled trials focusing on 6 NSAIDs, including etoricoxib, celecoxib, meloxicam, diclofenac, naproxen and beta-D-mannuronic acid (M2000), were analyzed in the present study. The efficacy endpoints included total pain score, patients' global assessment of disease activity (PGA), Bath Ankylosing Spondylitis Functional Index (BASFI) and the rate of achieving an Assessment in Ankylosing Spondylitis 20% response (ASAS20). The safety endpoints included total adverse events (AEs), gastrointestinal (GI) AEs, withdrawals due to AEs and serious AEs. NSAIDs were compared with the placebo and among themselves using Bayesian network meta-analysis, calculating mean differences (MDs) for continuous data and odds ratios for dichotomous data. The analysis revealed that all NSAIDs were significantly more effective in reducing pain severity than placebo (MDs between -17.49 and -25.99). Similarly, significant improvements in PGA, BASFI and ASAS20 were determined in patients receiving NSAIDs. Furthermore, etoricoxib was ranked as the most efficacious treatment for patients with AS. With regard to safety, there were no significant differences between NSAIDs and placebo in terms of total AEs, withdrawals due to AEs or serious AEs. Furthermore, no significant differences in AEs were identified between M2000 and the placebo. However, patients treated with diclofenac and naproxen had a higher risk of GI events than those taking placebo. In conclusion, the NSAIDs were all highly effective and well-tolerated in the treatment of AS. However, clinicians should take GI toxicity into account when prescribing NSAIDs.

HLA-B27 Negativity Is Associated With Renal Function Decline in Patients With Ankylosing Spondylitis and Secondary IgA Nephropathy

This study aimed to determine the impact of HLA-B27 on clinical phenotype and renal function during follow-up periods in patients with ankylosing spondylitis (AS) and secondary IgA nephropathy (IgAN). This single-center retrospective study included 71 AS patients with secondary IgAN. Renal function decline was defined as a mean eGFR decline of more than 5 mL/min/1.73 m² per year or progression into the dialysis stage. The association between HLA-B27 status and renal function decline was evaluated by univariable and multivariable Cox regression analyses. The results showed that seven (9.85%) of the 71 included patients were HLA-B27-negative. The median follow-up period was 4.0 years. HLA-B27-negative patients showed higher levels of uric acid (UA) than those who were HLA-B27-positive. Pathologically, a higher percentage of globally sclerotic glomeruli was observed in HLA-B27-negative patients. Survival analysis indicated that HLA-B27 negativity was associated with a significantly higher probability of renal function decline than HLA-B27 positivity. This significant association was also found in subgroup analyses of patients with either substantial proteinuria (more than 1.0 g per day) or interstitial fibrosis and tubular atrophy. Multivariable analysis showed that HLA-27 negativity was independently associated with renal function decline (HR 6.58; 95% CI 1.65 to 26.21; p = 0.008). In conclusion, HLA-B27 negativity is associated not only with a higher level of UA and a higher percentage of globally sclerotic glomeruli in AS patients with secondary IgAN but with renal function decline during follow-up periods.

Dual neutralisation of interleukin-17A and interleukin-17F with bimekizumab in patients with active ankylosing spondylitis: results from a 48-week phase IIb, randomised, double-blind, placebo-controlled, dose-ranging study

OBJECTIVES

Bimekizumab selectively neutralises both interleukin (IL)-17A and IL-17F. We report efficacy and safety in a phase IIb dose-ranging study in patients with active ankylosing spondylitis (AS).

METHODS

Adults with AS (fulfilling modified New York criteria) were randomised 1:1:1:1:1 to bimekizumab 16 mg, 64 mg, 160 mg, 320 mg or placebo every 4 weeks for 12 weeks (double-blind period). At week 12, patients receiving bimekizumab 16 mg, 64 mg or placebo were re-randomised 1:1 to bimekizumab 160 mg or 320 mg every 4 weeks to week 48; other patients continued on their initial dose (dose-blind period). The primary end point was Assessment of SpondyloArthritis international Society (ASAS) 40 response at week 12 (non-responder imputation (NRI) for missing data).

RESULTS

303 patients were randomised: bimekizumab 16 mg (n=61), 64 mg (n=61), 160 mg (n=60), 320 mg (n=61) or placebo (n=60). At week 12, significantly more bimekizumab-treated patients achieved ASAS40 vs placebo (NRI: 29.5%-46.7% vs 13.3%; p<0.05 all comparisons; OR vs placebo 2.6-5.5 (95% CI 1.0 to 12.9)). A significant dose-response was observed (p<0.001). The primary end point was supported by all secondary efficacy outcomes. At week 48, 58.6% and 62.3% of patients receiving bimekizumab 160 and 320 mg throughout the study achieved ASAS40, respectively (NRI); similar ASAS40 response rates were observed in re-randomised patients. During the double-blind period, treatment-emergent adverse events occurred in 26/60 (43.3%) patients receiving placebo and 92/243 (37.9%) receiving bimekizumab.

CONCLUSIONS

Bimekizumab provided rapid and sustained improvements in key outcome measures in patients with active AS, with no unexpected safety findings versus previous studies.

TRIAL REGISTRATION NUMBER

NCT02963506.

Comparative persistence of anti-tumor necrosis factor therapy in ankylosing spondylitis patients: a multicenter international study

Objective: To evaluate persistence on conventional DMARDs (cDMARDs) and anti-TNF therapies, and to identify potential determinants of discontinuation among individuals with ankylosing spondylitis (AS) living in Brazil and Quebec, Canada.Methods: We conducted a cohort study of AS patients using health administrative data (2010-2015). One-year and 2-year persistence rates were assessed. Cox regression was used to identify potential determinants of therapy discontinuation.Results: One-year persistence was less likely in Brazil for both anti-TNF and cDMARDs (Brazil: 62.1 and 30.7%, Quebec: 66.9 and 67.0%). The 2-year persistence rates were lower for both anti-TNF and cDMARD, but remained higher in Quebec (Brazil: 47.9 and 18.1%, Quebec: 51.5 and 53.5%). In multivariate Cox regression analysis, age, sex and comorbidities were associated with persistence in both countries. In Quebec, persistence did not differ between rural and urban regions or with socioeconomic status. While in Brazil, patients in regions with higher Human Development Index and those in cities with lower Gini index were less likely to discontinue therapy.Conclusions: Canadian AS patients were more likely to persist on therapy compared to Brazilian patients, although rates were lower at 2 years in both countries. Socioeconomic disparity in persistence was found in Brazil, but not in Quebec.

How Do Patients With Axial Spondyloarthritis Experience High-Intensity Exercise?

Objective

In a few studies, high‐intensity exercise has displayed beneficial effects on cardiovascular health among patients with rheumatic diseases, yet the high‐intensity exercise mode is still not fully accepted among health care professionals. The aim of this study was to investigate experiences of high‐intensity exercise among patients with axial spondyloarthritis.

Methods

Fourteen respondents who had participated in a high‐intensity exercise program for 12 weeks were included in this qualitative study with individual semistructured, in‐depth interviews. The respondents’ median age was 53, ranging from 23 to 63 years old, and both men and women of different ethnicities were represented. Interviews were analyzed by qualitative content analysis, including both manifest content and interpretations of underlying latent meaning.

Results

The analysis resulted in five categories describing the respondents’ experiences with high‐intensity exercise: 1) high‐intensity exercise as a challenge for both body and mind, 2) increased faith in one's own body, 3) changed attitude toward exercise, 4) taking charge of one's own health by challenging the disease, and 5) exercise in a social context.

Conclusion

Supervised high‐intensity interval exercise was perceived as challenging for both body and mind but was also described as a positive experience, with rapid bodily effects that strengthened respondents’ faith in their own bodies. The new experience seemed to have changed the respondents’ attitude and motivation for exercise and made them start taking charge of their health by challenging the disease. Exercise in a social context, under professional leadership, enhanced exercise self‐efficacy and helped the respondents to adhere to the exercise program.

MicroRNAs in ankylosing spondylitis: Function, potential and challenges

Epigenetic mechanisms such as DNA methylation, histone modifications and non-coding RNA, are considered the essential connection between a disorder's onset and the environment, on a permissive genetic background. Among autoimmune and inflammatory-mediated disorders, Ankylosing Spondylitis (AS), a chronic arthritis of the spine, is a very good example for the weight of epigenetics' contribution. MicroRNAs (miRNAs) are single-stranded nucleotides which regulate gene expression and are involved in pathological and physiological processes. In this manuscript we provide a clarification on the role of microRNAs in AS, with a focus on the mechanisms of pathogenesis. In specific, we have examined the contribution of miRNAs in the processes of inflammation, new bone formation and T-cell function, and the pathways (i.e. Wnt, BMP, TGFβ signalling etc.) they regulate. The utility of miRNAs in better understanding AS pathogenesis is undisputed and their utility as therapeutic opportunity is strongly increasing.

Added value of biomarkers compared with clinical parameters for the prediction of radiographic spinal progression in axial spondyloarthritis

OBJECTIVES

The objective of this study was to examine whether adding biomarkers to routine clinical parameters improves prediction of radiographic spinal progression in axial spondyloarthritis.

METHODS

One hundred and seventeen patients with ankylosing spondylitis who completed the Effects of NSAIDs on RAdiographic Damage in Ankylosing Spondylitis (ENRADAS) trial were included. Radiographic spinal progression was defined as worsening of the modified Stoke Ankylosing Spondylitis Spine Score by ⩾2 points after 2 years. A clinical prediction model was constructed out of baseline syndesmophytes, elevated CRP, cigarette smoking and male sex. The following serum biomarkers were measured at baseline by ELISA: MMP3, VEGF, calprotectin, leptin, high molecular weight adiponectin, osteoprotegerin, sclerostin, N-terminal telopeptide, procollagen type II N-terminal propeptide and serum amyloid A.

RESULTS

Repeated cross-validation analyses revealed one biomarker combination with potential added predictive value in addition to the clinical model: leptin + high molecular weight adiponectin + VEGF. This biomarker combination showed an area under the curve (AUC)Biomarkers = 0.731 (95% CI: 0.614, 0.848), which was numerically superior to the clinical model [AUCClinical = 0.665 (95% CI: 0.553, 0.776)]. A combination of clinical parameters + biomarkers showed an improved predictive value compared with the clinical model reflected by AUCClinical+Biomarkers = 0.768 (95% CI: 0.666, 0.871), though not statistically significant (P = 0.051). However, by considering the part of the receiver operating characteristic curve with a specificity ⩾75% resulting in partial AUC (pAUC), the improvement becomes significant (pAUCClinical+Biomarkers = 0.119; pAUCClinical = 0.053; P = 0.01).

CONCLUSION

Biomarkers show potential to improve the prediction of radiographic spinal progression in axial spondyloarthritis when used in addition to the clinical parameters, though the added value seems to be rather small.

Is a positive family history of spondyloarthritis relevant for diagnosing axial spondyloarthritis once HLA-B27 status is known?

Objectives

A positive family history (PFH) of spondyloarthritis, in particular a PFH of AS or acute anterior uveitis, is associated with HLA-B27 carriership in chronic back pain patients. As it is unknown, the study aimed to investigate if a PFH contributes to diagnosing axial spondyloarthritis (axSpA) once HLA-B27 status is known.

Methods

In axSpA-suspected patients from the Assessment of SpondyloArthritis international Society (ASAS), DEvenir des Spondyloarthropathies Indifférenciéés Récentes (DESIR) and SPondyloArthritis Caught Early (SPACE) cohorts, logistic regression analyses were performed with HLA-B27 status and PFH according to the ASAS definition (ASAS-PFH) as determinants and clinical axSpA diagnosis as outcome at baseline. Analyses were repeated with a PFH of AS or acute anterior uveitis.

Results

In total, 1818 patients suspected of axSpA were analysed (ASAS n = 594, DESIR n = 647, and SPACE n = 577). In patients from the ASAS, DESIR and SPACE cohorts, respectively 23%, 39% and 38% had an ASAS-PFH, 52%, 58% and 43% were HLA-B27 positive, and 62%, 47% and 54% were diagnosed with axSpA. HLA-B27 was independently associated with an axSpA diagnosis in each cohort but an ASAS-PFH was not [ASAS cohort: HLA-B27 odds ratio (OR): 6.9 (95% CI: 4.7, 10.2), ASAS-PFH OR: 0.9 (95% CI: 0.6, 1.4); DESIR: HLA-B27 OR: 2.1 (95% CI: 1.5, 2.9), ASAS-PFH OR: 1.0 (95% CI 0.7, 1.3); SPACE: HLA-B27 OR: 10.4 (95% CI: 6.9, 15.7), ASAS-PFH OR: 1.0 (95% CI: 0.7, 1.5)]. Similar negative results were found for PFH of AS and acute anterior uveitis.

Conclusion

In three independent cohorts with different ethnical backgrounds, ASAS, DESIR and SPACE, a PFH was not associated independently of HLA-B27 with a diagnosis of axSpA. This indicates that in the vast majority of patients presenting with back pain, a PFH does not contribute to the likelihood of an axSpA diagnosis if HLA-B27 status is known.

Enthesitis-related Arthritis: Prevalence and Complications of Associated Uveitis in Children and Adolescents From a Population-based Nationwide Study in Germany

Objective.

Enthesitis-related arthritis (ERA) represents a subgroup of juvenile idiopathic arthritis (JIA) that is regularly accompanied by anterior uveitis. This study describes the prevalence and characteristics of ERA-related uveitis.

Methods.

Cross-sectional data from the National Pediatric Rheumatological Database (NPRD) were used to characterize ERA-related uveitis (ERA-U). In addition to sociodemographic variables, we documented the occurrence of uveitis and course of disease, including symptoms, visual acuity, and complications, as well as JIA characteristics such as disease activity (Juvenile Arthritis Disease Activity Score 10), functional ability (Childhood Health Assessment Questionnaire score), laboratory variables, and treatment.

Results.

In the years from 2002 to 2014, there were 3778 (15.2%) of a total of 24,841 JIA patients recorded in the NPRD who had ERA, and 280 (7.4%) of them had developed uveitis. Detailed ophthalmological documentation by a uveitis add-on module was available for 22.9% of these patients. Uveitis onset was acutely symptomatic in 63% of patients. Patients with uveitis were more frequently male, HLA-B27–positive, younger at ERA onset, and they had higher erythrocyte sedimentation rate values at first uveitis documentation than those without uveitis. Uveitis was diagnosed at a mean age of 11.5 (± 3.9) years (50% within 2 years after ERA onset). Systemic treatment with corticosteroids and synthetic and biologic disease-modifying antirheumatic drugs was associated with a (not significantly) lower risk of developing uveitis.

Conclusion.

The course of disease in ERA-U patients is frequently similar to HLA-B27–associated uveitis in adults; however, a subgroup of patients presents with asymptomatic uveitis.

Test-retest repeatability of the apparent diffusion coefficient in sacroiliac joint MRI in patients with axial spondyloarthritis and healthy individuals

Background

The apparent diffusion coefficient (ADC) may be used as a biomarker to diagnose axial spondyloarthritis (axSpA) and monitor therapeutic response.

Purpose

To measure the repeatability of the ADC in healthy individuals and in patients with axSpA with and without active sacroiliitis in a test–retest set-up, and to correlate ADC to conventional magnetic resonance imaging (MRI) bone marrow edema (BME) scores and clinical findings.

Material and Methods

A total of 25 patients with axSpA and 24 sex- and age-matched healthy individuals were prospectively examined with MRI twice within 10 days. Short tau inversion recovery (STIR), T1-weighted and diffusion-weighted imaging sequences were performed. Mono-exponential ADC maps were based on four b-values: 0; 50; 500; and 800. Inter-study repeatability and intra-reader reproducibility were investigated in subgroups, as were associations with conventional MRI and clinical findings.

Results

The inter-study repeatability for the median ADC was moderate for all individuals (intraclass correlation coefficient [ICC] 0.66); it was good in patients with axSpA (ICC 0.79) and poor in healthy individuals (ICC 0.27). Significant differences in ADC were found between women and men (P = 0.03), and between patients with versus without BME on STIR (P = 0.01). ADC was associated with an MRI BME score and with age in women.

Conclusion

ADC seems to be a repeatable parameter in patients with axSpA but not in healthy individuals. ADC is correlated with MRI sacroiliac joint BME score and with age in women.

The Interrelations between Biological and Targeted Synthetic Agents Used in Inflammatory Joint Diseases, and Obesity or Body Composition

Obesity is a comorbidity that plays a role in the development and severity of inflammatory joint diseases, including rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis. The relationships between obesity and adipose tissue and the treatments given for inflammatory joint diseases are bidirectional. In fact, biological agents (bDMARDs) and targeted synthetic agents (tsDMARDs) may influence body weight and body composition of treated patients, while obesity in turn may influence clinical response to these agents. Obesity is a prevalent comorbidity mainly affecting patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) with specific phenotypes. Tumour necrosis factor alpha (TNFα) inhibitors have been associated with changes in body composition by improving lean mass, but also by significantly increasing fat mass, which localized toward the abdominal/visceral region. The IL-6 inhibitor tocilizumab is associated with an increase in lean mass without change in fat mass. The clinical response to TNFα inhibitors is attenuated by obesity, an effect that is less pronounced with IL-6 inhibitors and the B-cell depletion agent rituximab. Conversely, body weight has no influence on the response to the costimulation inhibitor abatacept. These effects may be of help to the physician in personalized medicine, and may guide the therapeutic choice in obese/overweight patients.

Juvenile idiopathic arthritis and the gut microbiome: Where are we now?

In recent decades, because of advances in technology there has been an explosion of knowledge on how microbiome affects human health. In most chronic immune-inflammatory diseases, alterations in gut microbiome has been shown. The successful use of faecal microbial transplants for the treatment of clostridium difficile associated diarrhoea has also paved the way for novel therapies. Gut microbiome is affected by early life events like the mode of delivery, breast feeding, the use of antibiotics, etc. and that may have an indirect effect on the developing immune system as well as on the predisposition to juvenile idiopathic arthritis (JIA). Multiple studies have found altered gut microbiome in JIA though no single organism or microbial community has been found to be associated with JIA. In JIA, attempts to modify gut microbiome by using probiotics, exclusive enteral nutrition and other modalities have had variable success. The current review discusses the current data available on gut microbiome in different categories of JIA and how this knowledge can translate into new therapies.

Circulating Retinol-Binding Protein 4 as a Possible Biomarker of Treatment Response for Ankylosing Spondylitis: An Array-Based Comparative Study

Objective

To explore proteins associated with ankylosing spondylitis (AS) and to investigate potential proteins that may predict treatment response of adalimumab (ADA) in AS patients.

Methods

In the discovery cohort, 39 AS patients and 20 healthy controls (HCs) were included, and 16 AS patients received ADA treatment for 24 weeks after included. In the validation cohort, 43 AS patients and 39 HCs were enrolled, and all 43 patients received ADA treatment after enrollment. Blood samples and clinical information were collected from two cohorts at baseline from all participants and week 24 from patients received ADA treatment. A human antibody array containing 1,000 proteins was used in the discovery phase, and Elisa kits were used for protein validation.

Results

Compared with HCs, we identified 53 differentially expressed proteins (DEPs) in AS patients. Bioinformatics analysis revealed they were mostly enriched in coagulation function-related pathways, acute response signaling, and LXR/RXR activation. Bone metabolism pathways were also associated. Comparison between samples of pre- and post-ADA treatment revealed 42 DEPs. They were mostly associated with bone metabolism and inflammation response pathways. Significant enrichment was also found in LXR/RXR activation but not the coagulation function-related pathways. Upstream regulator analysis suggested that most regulators also significantly functioned under usage of ADA. Precisely, seven proteins were abnormally expressed in AS and restored after ADA treatment. Retinol-binding protein 4 (RBP4), one of the seven proteins, was validated that its baseline levels were inversely correlated with improvements in Ankylosing Spondylitis Disease Activity Score-C-reactive protein (ASDAS-CRP). Likewise, percentage changes in RBP4 levels were inversely correlated with changes in ASDAS-CRP score.

Conclusion

A dysregulated serum protein profile existed in AS. ADA exerted a considerable but not entire alteration toward the dysregulation. RBP4 could be a biomarker for predicting and monitoring ADA treatment response.

Antinuclear Antibodies and Lupus-like Manifestations in Rheumatoid Arthritis and Ankylosing Spondylitis Patients at 4 Months' Follow-up After Treatment with Infliximab and Etanercept

Background:

Up to 44% of patients treated with infliximab and 7% of patients treated with etanercept reported to have anti-drug antibodies within the first 6 months of treatment. Recently, anti-TNF-α therapies have been reported to be employed in the induction of the druginduced lupus erythematous.

Objective:

The aim of the present study was to investigate the relationship between anti-TNFα antibodies and various manifestations of lupus erythematous.

Methods:

We enrolled a total of 56 cases divided into 28 known cases of rheumatoid arthritis and 28 cases of ankylosing spondylitis patients and 56 controls. The case group was divided into 4 groups according to the underlying disease (RA or AS) and treatment regimen (infliximab or etanercept). ANA and anti-dsDNA levels and lupus criteria were assessed at the beginning of the study and 4 months after the initiation of anti-TNFα.

Results:

36% and 21% of RA patients treated with infliximab, were ANA and anti-dsDNA positive after 4 months (P=0.003, P=0.025). 28% and 7% of RA patients treated with etanercept, were ANA and anti-dsDNA positive after 4 months (P=0.009, P=0.15). 21% and 7% of AS patients treated with infliximab, were ANA and anti-dsDNA positive, respectively (P=0.025, P=0.15). 14% and 7% of AS patients treated with etanercept, were ANA and anti-dsDNA positive, respectively (P=0.63, P=0.15). Three patients who were positive for auto-antibodies developed three criteria for SLE.

Conclusions:

Infliximab potentially may increase both ANA and anti-dsDNA levels in rheumatoid arthritis, but only ANA in ankylosing spondylitis patients. In general, clinicians should consider different clinical symptoms of ATIL, which may be present as a lupus-like syndrome similar to idiopathic SLE or classical DIL.

The IgG galactosylation ratio is higher in spondyloarthritis patients and associated with the MRI score

OBJECTIVES

MRI is an important tool for evaluating inflammation levels and assessing treatment response in patients with ankylosing spondylitis (AS). However, it is expensive and requires experienced physicians. The goal of this study was to identify a biomarker correlated with the MRI score.

METHODS

A total of 558 spondyloarthritis (SpA) patients including 527 AS patients, 10 psoriasis (PsA) patients, and 21 non-radiographic SpA (nr-SpA) patients and 725 controls were enrolled for the studies. Plasma IgG galactosylation (IgG-Gal) level was measured by mass spectrometry. Clinical indexes such as Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and C-reactive protein (CRP) were measured in all AS patients. MRIs and X-rays were obtained from 65 AS patients who were followed up for 6 months.

RESULTS

The IgG-Gal ratio was twice as high in the AS patients compared with the controls. It correlated with inflammation indices which is evaluated by MRI according to SPARCC. (Pearson coefficient/p value was 0.6/7E10-6). In addition, AS patients with a higher IgG-Gal ratio at baseline tended to show greater improvement in inflammation scores by MRI both in 3-month follow-up and 6-month follow-up.

CONCLUSION

The IgG-Gal ratio was significantly increased in AS patients. In clinical care, it may be used as a potential biomarker for diagnosis in the future. Key Points • IgG galactosylation level was abnormal in SpA patients. • IgG galactosylation level was associated with MRI indices.

The roles of ERAP1 and ERAP2 in autoimmunity and cancer immunity: New insights and perspective

Autoimmunity and cancer affect millions worldwide and both, in principal, result from dysregulated immune responses. There are many well-known molecules involved in immunological process playing as a double-edged sword, by which associating autoimmune diseases and cancer. In this regard, Endoplasmic reticulum aminopeptidases (ERAP) 1, which belongs to the M1 family of aminopeptidases, plays a central role as a "molecular ruler", proteolyzing of N-terminal of the antigenic peptides before their loading onto HLA-I molecules for antigen presentation in the Endoplasmic Reticulum (ER). Several genome-wide association studies (GWAS) highlighted the significance of ERAP1 and ERAP2 in autoimmune diseases, including Ankylosing spondylitis, Psoriasis, Bechet's disease, and Birdshot chorioretinopathy, as well as in cancers. The expression of ERAP1/2 is mostly altered in different cancers compared to normal cells, but how this affects anti-cancer immune responses and cancer growth has been little explored. Recent studies on the immunological outcomes and the catalytic functions of ERAP1 and ERAP2 have provided a better understanding of their potential pathogenetic role in autoimmunity and cancer. In this review, we summarize the role of ERAP1 and ERAP2 in the autoimmune diseases and cancer immunity based on the recent advances in GWAS studies.

[Cost of illness in axial spondylarthritis for patients with and without tumor necrosis factor inhibitor treatment: results of a routine data analysis]

BACKGROUND

Tumour necrosis factor-alpha inhibitors (TNFi) are an effective but expensive treatment option in axial spondylarthritis (axSpA) patients who fail to achieve disease control under conventional treatment.

OBJECTIVE

The aim of this study was to assess the cost of illness in axSpA patients treated with and without TNFi.

METHODS

Using German health insurance data, patients with axSpA who newly received TNFi between 2011 and 2015 were identified and matched by age and sex to a reference group of patients with axSpA without TNFi treatment. Costs for services performed in an outpatient setting, inpatient care, pharmacotherapy and for productivity loss due to absence from paid work were analyzed over a 2-year period. In patients treated with TNFi , the 2‑year period included 1 year before and 1 year after the initiation of TNFi.

RESULTS

Data from 1455 axSpA patients who received TNFi treatment were included in the analyses. Costs for services performed in an outpatient setting, inpatient care, pharmacotherapy (excluding TNFi) as well as productivity loss significantly decreased after initiation of TNFi. Mean total costs increased from € 6075 in the year prior to TNFi initiation to € 27,871 in the year after TNFi initiation. Excluding costs for TNFi, total costs decreased by 22% to € 4761. Mean total costs among the reference group of 1455 age and sex-matched axSpA patients who did not receive TNFi remained stable over 2 years: € 3939 in the first year vs. € 3832 in the second year.

CONCLUSION

Initiation of TNFi treatment led to a sharp increase in the total costs of axSpA patients. Part of this increase was offset by a decrease of costs for services performed in an outpatient setting, inpatient care, pharmacotherapy (excluding TNFi) as well as productivity loss. In patients who did not receive TNFi, the costs remained stable over 2 years.

Clinical, Economic, and Humanistic Burden Associated With Delayed Diagnosis of Axial Spondyloarthritis: A Systematic Review

INTRODUCTION

Few studies have evaluated the impact of delayed diagnosis of axial spondyloarthritis (axSpA) on the overall burden of disease. The objective of this review was to evaluate the available literature on the clinical, economic, and humanistic burden of delayed diagnosis in patients with axSpA.

METHODS

This systematic literature review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched the MEDLINE and Embase databases for English-language publications of original research articles (up to July 12, 2018) and conference abstracts (January 1, 2014, to July 12, 2018) reporting studies of adult patients with delayed diagnosis of axSpA associated with clinical, economic, or humanistic burden. Retrieved publications were screened for eligibility by two independent reviewers; discrepancies were resolved by a third independent reviewer. Data were extracted by one reviewer and validated by a second independent reviewer.

RESULTS

A total of 1391 publications were retrieved, of which 21 met the inclusion criteria and were included in the analysis. Of these, 15 reported data on clinical burden, nine on economic burden, and six on humanistic burden, with eight studies reporting a combination of clinical, economic, and/or humanistic burden. Patients with a delayed diagnosis of axSpA generally had higher disease activity, worse physical function, and more structural damage than those who received an earlier diagnosis. Patients with a delayed diagnosis also had a greater likelihood of work disability and higher direct and indirect healthcare costs than those who received an earlier diagnosis. Delayed diagnosis was associated with a greater likelihood for depression, negative psychological impacts, and worse quality of life.

CONCLUSIONS

Delayed axSpA diagnosis was associated with more functional impairment, higher healthcare costs, and worse quality of life, highlighting the importance of early recognition of axSpA to reduce extensive burden on patients and society. Plain language summary available for this article.

Tendon and ligament mechanical loading in the pathogenesis of inflammatory arthritis

Mechanical loading is an important factor in musculoskeletal health and disease. Tendons and ligaments require physiological levels of mechanical loading to develop and maintain their tissue architecture, a process that is achieved at the cellular level through mechanotransduction-mediated fine tuning of the extracellular matrix by tendon and ligament stromal cells. Pathological levels of force represent a biological (mechanical) stress that elicits an immune system-mediated tissue repair pathway in tendons and ligaments. The biomechanics and mechanobiology of tendons and ligaments form the basis for understanding how such tissues sense and respond to mechanical force, and the anatomical extent of several mechanical stress-related disorders in tendons and ligaments overlaps with that of chronic inflammatory arthritis in joints. The role of mechanical stress in 'overuse' injuries, such as tendinopathy, has long been known, but mechanical stress is now also emerging as a possible trigger for some forms of chronic inflammatory arthritis, including spondyloarthritis and rheumatoid arthritis. Thus, seemingly diverse diseases of the musculoskeletal system might have similar mechanisms of immunopathogenesis owing to conserved responses to mechanical stress.