Prevalence and current therapies of psoriatic arthritis in Japan: A survey by the Japanese Society of Psoriasis Research in 2016

A cross-sectional questionnaire survey involving physicians for the clarification of the diagnosis and current status of therapeutic intervention of psoriatic arthritis in Japan

Patients with psoriatic arthritis (PsA) often experience comorbid, irreversible joint destruction, therefore early diagnosis and treatment of PsA are important. The diagnosis requires a comprehensive assessment, which includes an interview, a physical examination, a visual examination of the skin and nails, a blood test, and an imaging test. To clarify how patients with PsA are actually diagnosed and how physicians collaborate among clinical departments, we conducted a web-based questionnaire survey of 500 physicians (dermatologists, rheumatologists, and orthopedists) frequently involved in PsA treatment in Japan. The survey showed that those patients are rarely confirmed to have axial arthritis, peripheral arthritis, enthesitis, or dactylitis by general dermatology practitioners (GP dermatologists). Overall, <60% of patients suspected of having PsA underwent PsA examination by GP dermatologists more than once every 6 months; this percentage is lower than that of patients who underwent PsA examination by rheumatologists and orthopedists. The Psoriatic Arthritis Screening and Evaluation (PASE) questionnaire is the most commonly used for PsA screening. However, users of PASE were only 11.0%, 25.3%, 14.8%, and 24.1% of GP dermatologists, attending dermatologists in hospitals (HP dermatologists), rheumatologists, and orthopedists, respectively. While >80% of HP dermatologists, rheumatologists, and orthopedists used imaging tests (ultrasound, X-ray, and magnetic resonance imaging) for PsA screening, only 40% of GP dermatologists performed imaging tests. Regarding the demands on the healthcare environment of PsA treatment, early diagnosis and treatment for PsA are crucial in every clinical department. The present study showed that GP dermatologists rarely perform imaging tests or confirm a PsA diagnosis, thus patients may miss out on appropriate treatment through collaboration among clinical departments and step-up therapy. Because patients with PsA present diverse comorbid clinical symptoms, early diagnosis, including routine imaging tests, and appropriate treatment in collaboration with other experts are necessary.

Prevalence of psoriatic arthritis in Chinese population with psoriasis: A multicenter study conducted by experienced rheumatologists

BACKGROUND

Reports on the prevalence of psoriatic arthritis (PsA) among Chinese patients with psoriasis are very limited. This study, conducted by rheumatologists, estimated the prevalence of PsA in a large number of Chinese patients with psoriasis.

METHODS

Consecutive patients with a confirmed diagnosis of psoriasis attending nine dermatology clinics in five hospitals were recruited. All psoriasis patients were asked to complete a questionnaire comprising 16 questions to identify possible cases of PsA. All patients with one or more positive answers to the questionnaire were evaluated by two experienced rheumatologists.

RESULTS

A total of 2434 psoriasis patients, including 1561 males and 873 females, were enrolled. Both the questionnaire and rheumatologists' examinations were completed in the dermatology clinics. The results identified 252 patients with PsA, comprising 168 males and 84 females. The overall prevalence of PsA among psoriasis patients was 10.4% (95% confidence interval [95% CI], 9.1%-11.7%). By sex, the prevalence was 10.8% (95% CI, 9.2%-12.5%) for males and 9.6% (95% CI, 7.7%-11.9%) for females and there was no significant sex difference in the prevalence of PsA (P = 0.38). Of the 252 PsA patients, 125 (49.6%, 95% CI, 41.3%-59.1%) were newly diagnosed by rheumatologists. Consequently, the prevalence of undiagnosed PsA among psoriasis patients was 5.2% (95% CI, 4.4%-6.2%).

CONCLUSION

The prevalence of PsA in the Chinese population with psoriasis is about 10.4%, which is almost double that of previous reports in the Chinese population, but lower than that in Caucasians.

Epidemiological survey of patients with psoriatic arthritis in the Japanese Society for Psoriasis Research from 2017 to 2020

The Japanese Society for Psoriasis Research (JSPR) conducted annual epidemiological surveys of patients with psoriatic arthritis (PsA). This study aimed to analyze a recent epidemiological survey of enrolled PsA patients in the JSPR from 2017 to 2020. A total of 1641 patients (1032 men [62.9%] and 609 women [37.1%]) were enrolled from 131 medical institutions. The mean ± standard deviation age of the patients was 51.4 ± 13.6 years and those at the onset of skin lesions and joint symptoms were 39.2 ± 15.8 and 47.9 ± 14.0 years, respectively. According to the Moll and Wright criteria, distal, oligoarticular, polyarticular, arthritis mutilans, and axial or spondyloarthritis types were 27.2%, 29.9%, 18.6%, 0.4%, and 6.6%, respectively. Approximately 56.3% of the patients had past history and comorbidities, such as hypertension (35.9%), dyslipidemia (20.7%), diabetes mellitus (19.2%), hyperuricemia (13.5%), cardiovascular disease (4.1%), and cerebrovascular disease (3.9%). Regarding systemic therapy, 55.9% and 45.5% of the patients were treated with oral medications and biologics, respectively. The most common oral medication was methotrexate (39.1%), followed by apremilast (27.4%). Non-steroidal anti-inflammatory drugs were also used in many patients (40.3%). Among the biologics, the most common was adalimumab (30.1%), followed by secukinumab (20.9%) and ixekizumab (17.0%). This survey shows the recent perspective of PsA in the Japanese society, which will lead to a better understanding of this disease, including patient characteristics, comorbidities, and treatment trends.

Early psoriatic arthritis in Japan: Post-hoc analyses from a survey by the Japanese Society of Psoriasis Research

To determine the characteristics of the early phase of psoriatic arthritis (PsA), we conducted a subanalysis of a retrospective survey of Japanese patients. In this study, we enrolled patients with early onset within either 2 years or 1 year from onset among the 1282 patients with PsA that had previously been reported. Among the total reported PsA patients, 304 (23.7%) were diagnosed with less than 2 years of onset of joint manifestation. The male : female ratio was 1.9:1, mean age at onset of cutaneous psoriasis 40.2 years, and that of joint manifestation 50.3 years. Age of less than 20 years at cutaneous psoriasis onset was observed in 22 cases, while that at joint manifestation was observed in two cases. Plaque-type psoriasis accounted for 90.1%, followed by psoriasis erythroderma (3.9%), pustular psoriasis (3.9%), and nail psoriasis (1.3%). Polyarthritis was the most common joint manifestation (32.9%), followed by distal interphalangeal (DIP) type (29.6%), oligoarthritis type (27.3%), and ankylosing spondylitis type (4.9%). Enthesitis was observed in 27.3% and dactylitis in 61.8%. Biologics were used in 168 cases (55.3%). By contrast, 199 patients (15.5%) were diagnosed within 1 year of onset of joint manifestation, among whom polyarthritis was the most common (30.7%). Biologics were used in 50.8%. In conclusion, the present study showed that the frequency of early PsA within 2 years of onset accounted for 23.7%, and those within 1 year of onset was 15.5% among the Japanese patients with PsA. Polyarthritis was the most common in early PsA patients.

LOOP, a cross-sectional, observational study investigating the clinical specialty setting as a determinant of disease management in psoriatic arthritis: Subgroup analysis results from Japan

Background

Psoriatic arthritis (PsA) is a progressive erosive joint disorder that causes functional impairment; therefore, early diagnosis and management are essential. This study evaluated the association between clinical specialty and the time to management in patients with PsA in Japan.

Methods

This was a subgroup analysis of a cross-sectional, multicenter, observational study that was conducted in 17 countries outside the United States, including 17 sites at 8 institutions in Japan, from June 2016 to October 2017. Data from consecutive patients (age ≥18 years) with a suspected or established diagnosis of PsA on a routine visit to a participating rheumatology/orthopedic or dermatology clinic in Japan were analyzed. The primary endpoints were time from onset of inflammatory musculoskeletal symptoms to PsA diagnosis, PsA diagnosis to first conventional synthetic disease-modifying antirheumatic drug (csDMARD), PsA diagnosis to first biologic DMARD (bDMARD), and first csDMARD to first bDMARD.

Results

Of 109 patients with a confirmed diagnosis of PsA, 39.4% (n = 43) and 60.6% (n = 66) were recruited by rheumatologists/orthopedists and dermatologists, respectively. Most patients were prescribed tumor necrosis factor inhibitors (58.7%) or methotrexate (56.0%). The mean duration from symptom onset to PsA diagnosis was significantly longer (p = 0.044) for patients treated by rheumatologists/orthopedists (70.6 months) than those treated by dermatologists (30.1 months). In the rheumatology/orthopedic and dermatology settings, the mean time from PsA diagnosis to first csDMARD administration was −0.9 and −2.9 months, and from PsA diagnosis to first bDMARD 21.4 and 14.9 months, respectively. The mean duration from administration of first csDMARD to first bDMARD was comparable in the rheumatology/orthopedic (31.8 months) and dermatology (31.5 months) settings.

Conclusions

Treatment approach was slightly different between rheumatology/orthopedic and dermatology setting in clinical practice in Japan, suggesting that an integrated dermo-rheumatologic approach can optimize the management of patients with PsA.

Psoriatic arthritis with skin lesions localized to the scalp: A case report

A 66-year-old man with a 2-year history of suspected scalp eczema with excessive dandruff developed painful swollen joints in the extremities. Four months after developing polyarthritis and polydactylitis, eczema gradually spread to the face. He was referred to our hospital for intractable scalp and facial eczema and polyarthritis. Based on the appearance of the head and facial skin lesions, psoriasis was suspected. Treatment with apremilast (a phosphodiesterase-4-inhibitor) was initiated, which swiftly alleviated the skin lesions. The joint deformities persisted, but the pain in the joints disappeared. This case implies that psoriatic arthritis should be suspected even if psoriatic skin lesions are localized to the scalp.

Safety and effectiveness of secukinumab in psoriasis vulgaris and psoriatic arthritis: Real-world evidence in Japan

Secukinumab, a fully human monoclonal antibody that selectively neutralizes interleukin‐17A, has been available for the treatment of moderate to severe psoriasis and psoriatic arthritis since February 2015 in Japan. Because there was a time gap after the previous approval of biologics for psoriatic disease indication, it was suggested that patients to be treated with secukinumab at its launch might have refractory disease symptoms. In order to assess the safety and effectiveness of secukinumab in those patients, a 52‐week, open‐label, multicenter, observational cohort study was conducted. In total, 306 and 250 patients were included in the safety and effectiveness analysis sets, respectively. Over half of patients had previously received biologics (56.9%). Adverse events, serious adverse events and adverse reactions were reported in 41.2%, 7.2% and 24.2% of patients, respectively. The most commonly reported adverse reactions were oral candidiasis (2.9%), consistent with those reported in clinical studies. In addition, none of the patient characteristics assessed for the effect on safety of secukinumab increased the occurrence of adverse reactions. Psoriasis Area and Severity Index score (mean ± standard deviation) improved from baseline (14.7 ± 12.3) to week 12 (1.78 ± 3.3), which was maintained up to week 24 (1.59 ± 3.0). The proportion of patients with a Dermatology Life Quality Index score of 0/1 improved from baseline (2.2%) to week 12 (64.7%) and sustained up to week 24 (71.4%). In addition to the skin symptoms, improvement was observed in all psoriatic arthritis disease‐related assessments. The current study reaffirmed the safety and effectiveness of secukinumab with broader patients than those in the clinical studies.

The contribution of IL-17 to the development of autoimmunity in psoriasis

Psoriasis is an (auto)immune-mediated disease that manifests as widespread desquamative erythema. The TNF-α/IL-23/IL-17A axis is crucial to its pathogenesis, which is demonstrated by its excellent therapeutic response to biologics that target this axis. There is a strong association between HLA-C*0602 and psoriasis, and researchers have identified autoantigens that are restricted to this major histocompatibility class I molecule. These auto-Ags include LL-37, A disintegrin and metalloprotease domain containing thrombospondin type 1 motif-like 5 (ADAMTSL5), and keratin 17. IL-17A-producing T cells have been identified in T cell populations that are reactive to these auto-Ags. In addition, lipid Ags have surfaced as candidate auto-Ags that activate IL-17A-producing T cells in a CD1a-restricted manner. In this article, we review the candidate auto-Ags that may contribute to the activation of the IL-17A-deviated immune response in psoriasis.

Real-World Postmarketing Study of the Impact of Adalimumab Treatment on Work Productivity and Activity Impairment in Patients with Psoriatic Arthritis

Introduction

This study investigated the effectiveness of adalimumab treatment in improving Work Productivity and Activity Impairment (WPAI) in patients with psoriatic arthritis (PsA) in real-world settings in Japan.

Methods

This 24-week, single-arm, postmarketing surveillance study (2014–2017), conducted at 75 centers in Japan, enrolled adalimumab-naïve patients (paid workers, including part-time) meeting ClASsification criteria for Psoriatic ARthritis (CASPAR). The primary endpoint was improvement in overall work impairment (OWI) scores from baseline to week 24. Secondary endpoints included changes in WPAI-PsA (OWI, absenteeism, presenteeism, and activity impairment), Psoriasis Area and Severity Index (PASI), psoriatic arthritis screening and evaluation (PASE) scores, Disease Activity Scores in 28 joints using C-reactive protein (DAS28[CRP]), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores, Health Assessment Questionnaire-Disability Index (HAQ-DI) scores, and PASI75/90 and American College of Rheumatology (ACR) 20/50/70 rates.

Results

In the effectiveness population (n = 106; 72.6% men; mean ± standard deviation [SD] age, 49.3 ± 10.7 years), OWI scores significantly improved (mean ± SD change, − 25.2 ± 35.3; p < 0.0001) from baseline to week 24. Other WPAI domain scores also improved significantly. Changes in OWI were significantly correlated (p < 0.0001) with PASE (r = 0.6284), DAS28(CRP) (r = 0.6059), BASDAI (r = 0.7281), and HAQ-DI (r = 0.6161) scores and were significantly influenced by previous nonsteroidal anti-inflammatory drug use (p = 0.0142), and baseline PASE (p = 0.0098), DAS28(CRP) (p = 0.0026), HAQ-DI (p = 0.0004), and BASDAI (p < 0.0001) scores. At the last evaluation, rate (95% confidence interval) of PASI 75 and 90 (n = 100) was 58.0% (47.7–67.8) and 39.0% (29.4–49.3), respectively, and that of ACR 20, 50, and 70 (n = 58) was 86.2% (74.6–93.9), 70.7% (57.3–81.9), and 53.4% (39.9–66.7), respectively. No new safety signals were observed in the safety population (n = 148).

Conclusion

Adalimumab treatment improved WPAI in patients with PsA. Improvements in OWI and joint symptoms were significantly associated.

Trial Registration Number

ClinicalTrials.gov identifier: NCT02414633.

Funding

AbbVie GK and Eisai Co., Ltd.

Electronic supplementary material

The online version of this article (10.1007/s12325-018-0866-y) contains supplementary material, which is available to authorized users.

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

Objective.

To delineate clinical characteristics of patients with spondyloarthritis (SpA) in Japan in comparison to other areas of the world.

Methods.

Using the ASAS-COMOSPA (Assessment of Spondyloarthritis international Society–COMOrbidities in SPondyloArthritis) data, an international cross-sectional observational study of patients with SpA, we analyzed information on demographics, disease characteristics, comorbidities, and risk factors. Patients were classified by region: Japan, other Asian countries (China, Singapore, South Korea, Taiwan), and non-Asian countries (Europe, the Americas, Africa). Patient characteristics, including diagnosis and treatment, were compared.

Results.

Among 3984 patients included in the study, 161 were from centers in Japan, 933 from other Asian countries, and 2890 from other regions. Of patients with SpA in Japan, 42 (26.1%) had peripheral SpA, substantially more than in other countries. This trend was explained by the predominance of psoriatic arthritis (PsA) among Japanese patients with SpA. In contrast to the relatively low number in Japan, 54% of patients from other Asian countries had pure axial SpA (axSpA) without peripheral features. HLA-B27 testing, considered an integral part of the classification of axSpA, was performed in only 63.6% of Japanese patients with axSpA. More than half of Japanese patients with axSpA were classified using imaging criteria.

Conclusion.

In our study, there was a more substantial number of peripheral SpA cases observed in Japan compared to other parts of Asia and other regions of the world. Aside from ethnic differences, increasing recognition of PsA in Japan, as well as a potential underdiagnosis of axSpA due to the insufficient use of HLA-B27 testing, may partly explain regional discrepancies.

Psoriasis and the TNF/IL23/IL17 axis

The excellent response of psoriasis to anti-TNF-α(TNF)/IL23/IL17A biologics implies a crucial role for the TNF/IL23/IL17 axis in developing psoriasis. In addition to the TNF/IL23/IL17 axis provided by immune cells, current evidence points to an important contribution of TNF, IL23 and IL17C produced from non-hematopoietic keratinocytes. Therefore, crosstalk between immune cells and keratinocytes forms a multilayered feed-forward loop to accelerate the TNF/IL23/IL17A axis. Many biologics have already been licensed or are under clinical trials. Given that the IL-17 signature is more upregulated in the skin than in synovium in psoriatic arthritis, anti-IL-23/IL-17 agents seem to be superior to anti-TNF-α remedies in the treatment of skin lesions. In this review, we summarize recent topics in psoriasis and the TNF/IL23/IL17 axis.

Cross-sectional multicenter observational study of psoriatic arthritis in Japanese patients: Relationship between skin and joint symptoms and results of treatment with tumor necrosis factor-α inhibitors

Psoriatic arthritis (PsA) is an inflammatory arthritis with as yet unclear pathophysiology. This retrospective, multicenter, cross-sectional study was conducted in 19 facilities in western Japan and aimed to identify patients' characteristics and factors that affect the results of treatment with biologic agents. Of 2116 patients with psoriasis, 285 (13.5%) had PsA. Skin manifestations preceded joint manifestations in 69.8%, the onset was simultaneous in 17.2%, whereas PsA preceded skin manifestations in 2.5%. Peripheral arthritis was most common, occurring in 73.7%, compared with axial disease in 21.8%, enthesitis in 23.5% and dactylitis in 35.4%. Patients with severe skin manifestations were significantly younger at onset (P = 0.02) and more frequently had axial disease (P < 0.01). Biologic agents were used in 206 patients (72.3%), anti-tumor necrosis factor (TNF)-α antibodies being prescribed first to 157 of them. Anti-TNF-α antibodies were continued by 105 participants and discontinued by 47, the remaining five patients being lost to follow up. Patients who discontinued anti-TNF-α antibodies were significantly older than those who continued (55 vs 51 years, P = 0.04) and significantly older at onset of joint manifestations (50 vs 44 years, P = 0.01). Multivariate analysis revealed that patients over 50 years significantly more frequently terminated anti-TNF-α antibodies (P < 0.01). In conclusion, patients with PsA and severe skin manifestations have earlier onset and axial disease, which seriously impacts on quality of life. Anti-TNF-α antibodies were generally effective enough to continue but less so in patients aged over 50 years. Further detailed research is needed.

Differential efficacy of biologic treatments targeting the TNF-α/IL-23/IL-17 axis in psoriasis and psoriatic arthritis

Psoriasis and psoriatic arthritis cause significant physical and psychological burdens for afflicted individuals. An accelerated TNF-α/IL-23/IL-17 axis is their major pathomechanism; therefore, anti-TNF-α/IL-23/IL-17 biologics are very effective for the treatment of skin and joint lesions in psoriasis and psoriatic arthritis. Given that the IL-17 signature is more upregulated in the skin than in synovium in psoriatic arthritis, anti-IL-23/IL-17 agents seem to be superior to anti-TNF-α remedies in the treatment of skin lesions. In this review, we focus on the differential efficacy of anti-TNF-α/IL-23/IL-17 biologics in psoriasis and psoriatic arthritis.

Autoimmunity and autoimmune co-morbidities in psoriasis

Psoriasis is characterized by widespread scaly erythematous plaques that cause significant physical and psychological burdens for the affected individuals. Accelerated inflammation driven by the tumour necrosis factor-α/interleukin-23/interleukin-17 axis is now known to be the major mechanism in the development of psoriasis. In addition, psoriasis has an autoimmune nature that manifests as autoreactive T cells and is co-morbid with other autoimmune diseases, such as autoimmune bullous diseases, vitiligo, alopecia and thyroiditis. In this article, we review the recent topics on autoimmunity and autoimmune co-morbidities in psoriasis.