Clinical Characteristics of Patients with Spondyloarthritis in Japan in Comparison with Other Regions of the World

A multicentre study of clinical features and HLA typing in Japanese patients with ankylosing spondylitis

OBJECTIVES

Due to the low prevalence of HLA-B27 and ankylosing spondylitis (AS) in Japan, rheumatologists have little experience with AS. We conducted a multicentre study to identify the characteristics and frequency of HLA-B types.

METHODS

We analysed epidemiological and clinical data, blood tests, spine radiographs, and HLA-B types in Japanese AS patients.

RESULTS

We evaluated 111 AS patients, predominantly men (82.9%). The mean age, disease onset, diagnosis, and time from onset to diagnosis were 43.7, 24.2, 36.0, and 11.6 years, respectively. Inflammatory low back pain was found in 96 cases (86.5%); peripheral arthritis in 59 (53.2%), enthesitis in 35 (31.5%), and dactylitis in 6 (5.4%). Extra-articular symptoms included uveitis, psoriasis, and inflammatory bowel disease in 41 (36.9%), 1 (0.9%), and 5 (4.5%) cases, respectively. HLA-B27 was positive in 83 cases (74.8%; odds ratio, 1146.0); and HLA-B48 in 9 (8.1%; odds ratio, 3.0). HLA-B27-positive patients were younger at onset and had a shorter diagnostic delay.

CONCLUSIONS

AS clinical symptoms were almost the same as other countries except for the low coexistence of psoriasis. HLA-B27 positivity in Japanese patients was 78%. HLA-B27-positive patients were younger and diagnosed earlier. In addition to HLA-B27, a relationship with HLA-B48 was suggested.

Clinical Characteristics of Patients With Psoriatic Spondylitis Versus Those With Ankylosing Spondylitis: Features at Baseline Before Biologic Therapy

BACKGROUND

Clinical characteristics and manifestations of psoriatic arthritis (PsA) have been extensively studied in western countries, yet data of Korean patients with PsA are very limited. We aimed to investigate the clinical traits of patients with PsA and dissect the characteristics of those with axial involvement.

METHODS

In this observational study, we analyzed clinical data of 109 patients with PsA who were enrolled in the Korean College of Rheumatology Biologics and Targeted Therapy registry between December 2012 and March 2022 at the time point of initiating or switching to a biologic agent. Data from 2,221 patients with ankylosing spondylitis (AS) registered during the same period were also analyzed. We divided patients with PsA into patients with or without axial involvement and then added AS patients with psoriasis (total three subgroups) for comparative analyses.

RESULTS

Asymmetric oligoarthritis was the most common clinical manifestation in patients with PsA, followed by symmetric polyarthritis and spondylitis. Our analysis indicated that methotrexate and sulfasalazine were the two most prescribed disease-modifying antirheumatic drugs for patients with PsA before starting biologic therapy. The patients with psoriatic spondylitis had more peripheral joint involvement (P = 0.016), less prior uveitis (P < 0.001), and lower human leukocyte antigen B27 (HLA-B27) positivity (P < 0.001) than the AS patients with psoriasis. Furthermore, syndesmophytes and radiographic sacroiliitis were prevalent among patients with PsA and AS patients with psoriasis who had the HLA-B27 gene.

CONCLUSION

Our study shows that the degree of peripheral arthritis is less severe in Korean patients with PsA who require biologics and reestablishes that psoriatic spondylitis is a common and important clinical pattern in Korean patients with PsA.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01965132.

What is peripheral spondyloarthritis? Identifying proportion, phenotype and burden in post hoc analysis of the ASAS-PerSpA study

BACKGROUND

Little is known about the prevalence, phenotype, and burden of peripheral spondyloarthritis (pSpA). The objective of the study is to compare the phenotype and burden of disease of pure pSpA to that of pure psoriatic arthritis (PsA), pure axial SpA (axSpA), and combined forms of SpA.

METHODS

This is a post hoc analysis of 4,185 patients from the cross-sectional ASAS-Peripheral involvement in SpA (PerSpA) study. Patients were approached in 2 ways: the first approach was based on the rheumatologist's diagnosis (diagnostic approach) and the second one was based on the fulfillment of ASAS or CASPAR classification criteria (classification criteria approach). Demographics, disease phenotype, and burden were compared among pure pSpA, PsA, axSpA, and the combined forms.

FINDINGS

The proportion of pSpA was 31.5% of SpA using the classification criteria approach and 10.3% using the diagnostic approach. pSpA was pure (i.e. without axSpA or PsA) in 16.8% of pSpA using the criteria, and in 62.3% using the diagnostic approach. Using classification criteria and diagnostic approach, respectively, pure pSpA patients had a high prevalence of peripheral joint disease (86 and 96%), synovitis (76 and 91%), and enthesitis (57 and 55%), a positive HLA-B27 in 65 and 59%, a high C-Reactive Protein level in 51% and inflammatory back pain in 52 and 42%. However, compared to pure PsA and pure axSpA, they had a significantly higher disease burden, but lower use of biologics using both approaches.

INTERPRETATION

The proportion of pSpA varies when using the classification criteria or the diagnostic approach. pSpA occurred in a pure form less frequently than PsA and axSpA and had intermediate features but a higher disease burden.

FUNDING

The PerSpA main study has been conducted under the umbrella of ASAS thanks to unrestricted grants from PFIZER, LILLY, ABBVIE, NOVARTIS, UCB, JANSSEN, MERCK.

Axial Spondyloarthritis in Japan

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Worldwide Differences in Clinical Phenotype of Axial Spondyloarthritis

PURPOSE OF REVIEW

This review aims to describe the variations in the clinical presentation of axial spondyloarthritis (axSpA) across the globe.

RECENT FINDINGS

We searched the PubMed database and screened more than 1360 articles; 60 of them were selected based on relevance to the topic being discussed and the goals of the review. Most of the clinical manifestations, including IBP, peripheral arthritis, and extra-articular involvement are seen in different regions of the world, but with appreciable clinical heterogeneity, possibly related to a smaller number of patients from some countries, and global variation in the prevalence of HLA-B27. For example, HLA-B27-positive patients have an earlier age of onset, higher prevalence of acute anterior uveitis, and greater familial occurrence. Peripheral arthritis and enthesitis are most commonly seen among axSpA patients from Latin America and Asia, whereas IBD appears to be slightly more common among Middle Eastern and North African patients. The main weakness encountered while reviewing these data is that some studies were small, and others were cross-sectional and retrospective; hence the inferences may have a selection bias. AxSpA is a very heterogenous disease with varied presentation across the globe, in part related to HLA-B27 positivity. It is imperative to further investigate the key regional differences as they impact timely disease recognition and initiation of early treatment. Therefore, there is a need for a large worldwide systematic study to capture the clinical picture of AxSpA in a more uniform manner.

Clinical characteristics of non-radiographic versus radiographic axial spondyloarthritis in Asia and non-radiographic axial spondyloarthritis in other regions: results of the cross-sectional ASAS-COMOSPA study

Objectives

To delineate characteristics of non-radiographic axial spondyloarthritis (nr-axSpA) in Asia versus non-Asian regions, and compare radiographic axSpA (r-axSpA) with nr-axSpA within Asia.

Methods

Data were collected from the Assessment of SpondyloArthritis international Society-COMOrbidities in SPondyloArthritis database. Categorising patients by region, we compared clinical characteristics between nr-axSpA from Asia vs elsewhere (Europe, the Americas and Africa). Within Asians, we additionally compared patient characteristics of those with nr-axSpA versus r-axSpA.

Results

Among 3984 SpA cases, 1094 were from Asian countries. Of 780 axSpA patients in Asia, 112 (14.4%) had nr-axSpA, less than in non-Asian countries (486/1997, 24.3%). Nr-axSpA patients in Asia were predominantly male (75.9% vs 47.1%), younger at onset (22.8 vs 27.8 years) and diagnosis (27.2 vs 34.5 years), and experienced less diagnostic delay (1.9 vs 2.9 years) compared with nr-axSpA in non-Asian countries. Nr-axSpA in Asia exhibited higher human leucocyte antigens-B27 prevalence (90.6% vs 61.9%), fewer peripheral SpA features (53.6% vs 66.3%) and similar extra-articular and comorbid disease rates compared with those with nr-axSpA in non-Asian countries. Disease activity, functional impairment and MRI sacroiliitis were less in nr-axSpA in Asia, with higher rates of non-steroidal anti-inflammatory drug response and less methotrexate and biological disease-modifying antirheumatic drugs use. Within Asia, r-axSpA showed higher disease activity and structural damage compared with nr-axSpA, with no differences in other features.

Conclusion

Among axSpA, lower frequency of nr-axSpA was observed in Asia. Our results offer an opportunity to better understand clinical characteristics and optimise diagnostic strategies, such as ensuring access and availability of MRI resources for accurate diagnosis of nr-axSpA in Asia.

Prevalence and distribution of peripheral musculoskeletal manifestations in spondyloarthritis including psoriatic arthritis: results of the worldwide, cross-sectional ASAS-PerSpA study

OBJECTIVES

To characterise peripheral musculoskeletal involvement in patients with spondyloarthritis (SpA) including psoriatic arthritis (PsA), across the world.

METHODS

Cross-sectional study with 24 participating countries. Patients with a diagnosis of axial SpA (axSpA), peripheral SpA (pSpA) or PsA according to their rheumatologist were included. The investigators were asked which diagnosis out of a list of six (axSpA, PsA, pSpA, inflammatory bowel disease-associated SpA, reactive arthritis or juvenile SpA (Juv-SpA)) fitted the patient best. Peripheral manifestations (ie, peripheral joint disease, enthesitis, dactylitis and root joint disease), their localisation and treatments were evaluated.

RESULTS

A total of 4465 patients were included (61% men, mean age 44.5 years) from four geographic areas: Latin America (n=538), Europe plus North America (n=1677), Asia (n=975) and the Middle East plus North Africa (n=1275). Of those, 78% had ever suffered from at least one peripheral musculoskeletal manifestation; 57% had peripheral joint disease, 44% had enthesitis and 15% had dactylitis. Latin American had far more often peripheral joint disease (80%) than patients from other areas. Patients with PsA had predominantly upper limb and small joint involvement (52%).Hip and shoulder involvement was found in 34% of patients. The prevalence of enthesitis ranged between 41% in patients with axSpA and 65% in patients with Juv-SpA. Dactylitis was most frequent among patients with PsA (37%).

CONCLUSION

These results suggest that all peripheral features can be found in all subtypes of SpA, and that differences are quantitative rather than qualitative. In a high proportion of patients, axial and peripheral manifestations coincided. These findings reconfirm SpA clinical subtypes are descendants of the same underlying disease, called SpA.

Changes in the proportion of clinical clusters contribute to the phenotypic evolution of Behçet's disease in Japan

Background

We hypothesized that Behçet’s disease (BD) consists of several clinical subtypes with different severity, resulting in heterogeneity of the disease. Here, we conducted a study to identify clinical clusters of BD.

Methods

A total of 657 patients registered in the Yokohama City University (YCU) regional BD registry between 1990 and 2018, as well as 6754 patients who were initially registered in the Japanese Ministry of Health, Labour and Welfare (MHLW) database between 2003 and 2014, were investigated. The YCU registry data regarding the clinical manifestations of BD, human leukocyte antigen (HLA) status, treatments, and hospitalizations were analyzed first, followed by similar analyses of the MHLW for validation. A hierarchical cluster analysis was independently performed in both patient groups.

Results

A hierarchical cluster analysis determined five independent clinical clusters in the YCU cohort. Individual counterparts of the YCU clusters were confirmed in the MHLW registry. Recent phenotypical evolutions of BD in Japan, such as increased gastrointestinal (GI) involvement, reduced complete type according to the Japan Criteria, and reduced HLA-B51 positivity were associated with chronologically changing proportions of the clinical clusters.

Conclusions

In this study, we identified independent clinical clusters among BD patients in Japan and found that the proportion of each cluster varied over time. We propose five independent clusters namely “mucocutaneous”, “mucocutaneous with arthritis”, “neuro”, “GI”, and “eye.”

Non-radiographic versus radiographic axSpA: what's in a name?

Axial spondyloarthritis is a heterogeneous inflammatory condition with variable clinical presentations and outcomes. The complexity of its diagnosis and absence of biomarkers hamper the development of diagnostic criteria with the risk of misuse of the available classification criteria in clinical practice and its consequences. Axial spondyloarthritis should be regarded as a continuum in which some patients, but not all, will have a more severe phenotype characterized by progression into new bone formation and joint fusion. Growing understanding of the factors that might drive disease progression and treatment response will allow for better characterization of treatment options and outcome for each affected individual. The aim of this review is to update the current evidence of what is axial spondyloarthritis and to highlight the need to focus on the concept rather than its classification.

Do geography and ethnicity play a role in juvenile Spondyloarthritis? A multi-center binational retrospective study

BACKGROUND

Observations among Israeli pediatric rheumatologists reveal that pediatric Juvenile Spondyloarthritis (JSpA) may present differently compared to patients from the United States (US). This study is aimed to compare the demographic and clinical variables of Israeli and US JSpA patients upon presentation.

METHODS

We performed a retrospective, cross-sectional, multicenter comparison of JSpA patients among 3 large Israeli pediatric rheumatology centers and a large US pediatric rheumatology center. Patients with diagnosis of Juvenile Ankylosing Spondylitis (JAS) and/or Enthesitis-related Arthritis (ERA) were included. The demographic, clinical and radiologic features were compared.

RESULTS

Overall 87 patients were included (39 Israeli, 48 US patients). Upon presentation, inflammatory back pain, sacroiliac joint tenderness and abnormal modified Schober test, were significantly more prevalent among Israeli patients (59% vs. 35.4, 48.7% vs. 16.7, and 41.2% vs. 21.5%, respectively, all p < 0.05), whereas peripheral arthritis and enthesitis were significantly more prevalent among US patients (43.6% vs. 91.7 and 7.7% vs. 39.6% in Israeli patients vs. US patients, p < 0.05). In addition, 96.7% of the Israeli patients versus 29.7% of the US patients demonstrated sacroiliitis on MRI (p < 0.001, N = 67). Less than one-third of the Israeli patients (32%) were HLA-B27 positive vs. 66.7% of US patients (p = 0.007).

CONCLUSION

Israeli children with JSpA presented almost exclusively with axial disease compared to US patients who were more likely to present with peripheral symptoms. HLA B27 prevalence was significantly lower in the Israeli cohort compared to the US cohort. Further studies are needed to unravel the genetic and possibly environmental factors associated with these findings.

Treatment patterns and health care resource utilization among Japanese patients with ankylosing spondylitis: A hospital claims database analysis

OBJECTIVES

To understand the current state of treatment patterns and health care resource utilization among patients in Japan with ankylosing spondylitis (AS) managed in the real-world setting.

METHODS

Patient records from the Medical Data Vision database were analyzed to identify patients with ICD-10 AS from April 2009 through July 2017. Measures evaluated included demographic, clinical, and other characteristics at diagnosis; treatment patterns; health care resource utilization; and costs.

RESULTS

Four hundred and seventeen patients met the study's inclusion criteria. Treatments observed during the first year after the initial AS diagnosis included nonsteroidal anti-inflammatory drugs (79.6%), corticosteroids (39.3%), methotrexate (22.3%), sulfasalazine (16.8%), adalimumab (14.2%), and infliximab (12.2%). At any time during the mean 33 months of study follow-up, biologic disease-modifying antirheumatic drugs (bDMARDs) were initiated by 115 patients. During the study follow-up, patients who initiated bDMARDs had higher median total per-patient annual health care costs ($26,937 vs $15,323), lower median per-patient hospitalization costs ($29,817 vs. $39,509), and fewer median hospital days per admission (7.0 vs. 11.0 days) compared with the overall group of patients diagnosed with AS.

CONCLUSION

This database study provides knowledge of patient characteristics, treatment patterns, HCRU, and costs for patients with AS in Japan. The study outcomes demonstrate a need for increased awareness of proper AS management.

Clinical practice recommendations for the use of imaging in the diagnosis and management of axial spondyloarthritis in Taiwan

OBJECTIVE

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease bearing challenges in early diagnosis. To improve clinical diagnosis and management of axSpA, recommendations were developed with current axSpA classification criteria and recent advances in medical imaging applications.

METHODS

A systematic literature review was conducted by 10 rheumatologists and radiologists in Taiwan to retrieve research evidence on the utilization of imaging modalities, including conventional radiography (CR), magnetic resonance imaging (MRI), computed tomography (CT), ultrasound (US), quantitative sacroiliac scintigraphy (QSS), and dual-energy X-ray absorptiometry (DXA). The panel of experts proposed six key issues on the role of imaging in early diagnosis of axSpA, monitoring of disease activity and structural changes, predicting treatment effects, and assessing complications such as osteoporosis and spinal fracture. The consensus was established on the basis of research evidence, clinical experiences and expert opinions. For each recommendation statement, the level of evidence was evaluated, the strength of recommendation was graded and the final level of agreement was determined through voting.

RESULTS

In total, four overarching principles and 13 recommendations were formulated. These recommendations outlined different imaging approaches in the diagnosis and management of axSpA disease progression. Considering CT is easy to perform when MRI is less available in Taiwan, the expert panel proposed a concise and practical diagnostic scheme to strengthen the valuable role of MRI and CT in the diagnostic evaluation of axSpA without evident radiographic features.

CONCLUSION

These modified recommendations provide guidance for rheumatologists, radiologists and healthcare professionals on timely diagnosis of axSpA and disease management with appropriate imaging modalities.