Advanced genomics and clinical phenotypes in psoriatic arthritis.

Psoriatic Arthritis (PsA) is a complex polygenic inflammatory disease showing a variable musculoskeletal involvement in patients with skin psoriasis. PsA coexist in 25-40 % of patients with the dermatological manifestations, but PsA may also predate the appearance of psoriasis. Nonetheless, the immunopathogenesis of psoriasis and PsA manifest significant similarities, with a major role of the individual susceptibility in both cases. Genome wide association studies (GWAS) identified several genes/loci associated with the risk to develop PsA, both dependent and independent of psoriasis. The major challenge is thus represented by the need to translate the identification of functional polymorphisms and other genetics findings into biological mechanisms along with the identification of novel putative drug targets. A functional genomics approach aims to increase GWAS power and recent evidence supports the use of a multilayer process, including eQTL, methylome, chromatin conformation analysis and genome editing to discover novel genes that can be affected by disease-associated variants, such as PsA. The available data have considered PsA as a unique homogeneous clinical entity while the clinical experience supports a wide variability of skin and joint manifestations coexisting in diverse patients with different mechanisms underlying the musculoskeletal and dermatological domains. A better discrimination of the patient features is encouraged by the limited data on functional genomics. We provide herein a review of the latest findings on PsA functional genomics highlighting the exciting developments in the field and how these might lead to a better understanding of gene regulation underpinning disease mechanisms and ultimately refine clinical phenotyping.

CCR4+ CD8+ T cells clonally expand to differentiated effectors in murine psoriasis and in human psoriatic arthritis.

Psoriasis is a chronic inflammatory skin disease with an autoimmune component and associated with joint inflammation in up to 30% of cases. To investigate autoreactive T cells, we developed an imiquimod-induced psoriasis-like inflammation model in K5-mOVA.tg C57BL/6 mice expressing ovalbumin (OVA) on the keratinocyte membrane, adoptively transferred with OT-I OVA-specific CD8+ T cells. We evaluated the expansion of OT-I CD8+ T cells and their localization in skin, blood, and spleen. scRNA-seq and TCR sequencing data from patients with psoriatic arthritis were also analyzed. In the imiquimod-treated K5-mOVA.tg mouse model, OT-I T cells were markedly expanded in the skin and blood at early time points. OT-I T cells in the skin showed mainly CXCR3+ effector memory phenotype, whereas in peripheral blood there was an expansion of CCR4+ CXCR3+ OT-I cells. At a later time point, expanded OVA-specific T-cell population was found in the spleen. In patients with psoriatic arthritis, scRNA-seq and TCR sequencing data showed clonal expansion of CCR4+ TCM cells in the circulation and further expansion in the synovial fluid. Importantly, there was a clonotype overlap between CCR4+ TCM in the peripheral blood and CD8+ T-cell effectors in the synovial fluid. This mechanism could play a role in the generation and spreading of autoreactive T cells to the synovioentheseal tissues in psoriasis patients at risk of developing psoriatic arthritis.

Immune cell activity during anti-TNF treatment in patients with psoriasis and psoriatic arthritis.

Psoriasis is a chronic, inflammatory skin disease characterized by a dysregulated immune response and systemic inflammation. Up to one-third of patients with psoriasis have psoriatic arthritis (PsA). Targeted treatment with antibodies neutralizing tumor necrosis factor (TNF) can ameliorate both diseases. We here explored the impact of long-term infliximab treatment on the composition and activity status of circulating immune cells involved in chronic skin and joint inflammation. Immune cells were analyzed by multicolor flow cytometry. We measured markers of immune activation in peripheral blood mononuclear cell (PBMC) populations in 24 infliximab-treated patients with psoriasis/psoriatic arthritis compared to 32 healthy controls. We observed a significant decrease in the frequency of both peripheral natural killer (NK) cells and their subset CD56dimCD16+ NK cells in PsA compared to healthy controls and patients with psoriasis. The latter had a strong positive correlation with PASI in these patients, while CD56brightCD16- NK cells were negatively correlated with PASI. In addition, we observed an upregulation of CD69+ intermediate CD14+CD16+ and CD69+ classical CD14+CD16- monocytes in PsA and increased activity of CD38+ intermediate CD14+CD16+ monocytes in patients with psoriasis. Compared to healthy controls, psoriasis patients demonstrated shifts of the three B cell subsets with a decrease in transitional CD27-CD38high B cells. Our exploratory study indicates a preserved pathophysiological process including continuous systemic inflammation despite clinical stability of the patients treated with infliximab.

Specific descriptions of axial involvement are associated with radiographic damage development after 2 years in psoriatic arthritis patients.

OBJECTIVES: Investigating the association between different definitions of axial involvement and syndesmophytes development over 2 years in patients with psoriatic arthritis (PsA). METHODS: Patients from a prospective multicentre cohort (Belgian Epidemiological Psoriatic Arthritis Study) involving 17 Belgian rheumatology practices were recruited between December 2012 and July 2014 and included when fulfilling the Classification Criteria for Psoriatic Arthritis. Axial involvement included six clinical and two radiographic oriented definitions.Two calibrated central readers evaluated radiographic damage by assessing the modified Stoke Ankylosing Spondylitis Spinal Score and modified New York criteria. New syndesmophytes after 2 years were described conditional on axial involvement at baseline. Logistic regression analyses were used to investigate the association between syndesmophyte development and axial involvement. All definitions of axial involvement were evaluated separately. RESULTS: From 150 patients, a 2-year follow-up of spinal radiographs was obtained. There are 11 patients with new syndesmophytes after 2 years. For the clinical definitions of axial involvement 'global assessment', 'detailed assessment', 'back pain (BP)' and 'inflammatory BP (IBP)' the probabilities of developing syndesmophytes ranged between 0.06 and 0.08 and were similar for the presence or absence of the definition. When including elevated C reactive protein (CRP) to the definitions the probability of developing syndesmophytes over 2 years increased two times for CBP and seven times for IBP.With radiographic axial involvement a similar trend was seen; radiographic sacroiliitis as definition showed a probability three times higher. When combined with elevated CRP there would be a 14 times higher chance to develop syndesmophytes in 2 years. The ORs varied from 0.83 to 13.80, though none of them were statistically significant. CONCLUSIONS: The likelihood of syndesmophyte formation in PsA is low. The probability of developing syndesmophytes is much higher when axial involvement is determined radiographically rather than clinically, particularly in the context of high CRP.

Validation and incorporation of digital entheses into a preliminary GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis.

OBJECTIVES: The main objective was to generate a GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis and to test its reliability. To this end, we assessed the validity, feasibility and applicability of ultrasound assessment of finger entheses to incorporate them into the scoring system. METHODS: The study consisted of a stepwise process. First, in cadaveric specimens, we identified enthesis sites of the fingers by ultrasound and gross anatomy, and then verified presence of entheseal tissue in histological samples. We then selected the entheses to be incorporated into a dactylitis scoring system through a Delphi consensus process among international experts. Next, we established and defined the ultrasound components of dactylitis and their scoring systems using Delphi methodology. Finally, we tested the interobserver and intraobserver reliability of the consensus- based scoring systemin patients with psoriatic dactylitis. RESULTS: 32 entheses were identified in cadaveric fingers. The presence of entheseal tissues was confirmed in all cadaveric samples. Of these, following the consensus process, 12 entheses were selected for inclusion in GLOUDAS. Ultrasound components of GLOUDAS agreed on through the Delphi process were synovitis, tenosynovitis, enthesitis, subcutaneous tissue inflammation and periextensor tendon inflammation. The scoring system for each component was also agreed on. Interobserver reliability was fair to good (κ 0.39-0.71) and intraobserver reliability good to excellent (κ 0.80-0.88) for dactylitis components. Interobserver and intraobserver agreement for the total B-mode and Doppler mode scores (sum of the scores of the individual abnormalities) were excellent (interobserver intraclass correlation coefficient (ICC) 0.98 for B-mode and 0.99 for Doppler mode; intraobserver ICC 0.98 for both modes). CONCLUSIONS: We have produced a consensus-driven ultrasound dactylitis scoring system that has shown acceptable interobserver reliability and excellent intraobserver reliability. Through anatomical knowledge, small entheses of the fingers were identified and histologically validated.

Mortality in patients with psoriatic arthritis in Sweden: a nationwide, population-based cohort study.

OBJECTIVES: To compare all-cause mortality and causes of death between patients with psoriatic arthritis (PsA) and the general population in Sweden. METHODS: Adults with at least one main PsA diagnosis (International Classification of Diseases-10: L40.5/M07.0-M07.3) from outpatient rheumatology/internal medicine departments 2001-2017 were identified from the National Patient Register. Each case was matched to five population comparator-subjects on sex/county/age at the case's first arthritis diagnosis. Follow-up ran from 1 January 2007, or from first PsA diagnosis thereafter, until death, emigration or 31 December 2018. Mortality was assessed overall, and stratified by sex and duration since diagnosis (diagnosis before/after 1 January 2007), using matched Cox proportional hazard regression (excluding/including adjustments for comorbidity) or Breslow test, as appropriate. Incidence rate ratios (IRR) of death, overall and stratified by sex/duration since diagnosis/age, as well as causes of death in PsA cases and comparator-subjects were also described. RESULTS: All-cause mortality was elevated in PsA (HR: 1.11 (95% CI: 1.07 to 1.16); IRR: 1.18 (95% CI: 1.13 to 1.22)), mainly driven by increased risks in women (HR: 1.23 (95% CI: 1.16 to 1.30)) and cases with longer time since diagnosis (HR: 1.18 (95% CI: 1.12 to 1.25)). IRR of death were significantly increased for all ages except below 40 years, with the numerically highest point-estimates for ages 40-59 years. When adjusted for comorbidity, however, the elevated mortality risk in PsA disappeared. Causes of death were similar among PsA cases/comparator-subjects, with cardiovascular disease and malignancy as the leading causes. CONCLUSIONS: Mortality risk in PsA in Sweden was about 10% higher than in the general population, driven by excess comorbidity and with increased risks mainly in women and patients with longer disease duration.

Rheuma-VOR study: optimising healthcare of rheumatic diseases by multiprofessional coordinating centres.

OBJECTIVES: Early diagnosis of inflammatory arthritis is critical to prevent joint damage and functional incapacities. However, the discrepancy between recommendations of early diagnosis and reality is remarkable. The Rheuma-VOR study aimed to improve the time to diagnosis of patients with early arthritis by coordinating cooperation between primary care physicians, specialists and patients in Germany. METHODS: This prospective non-randomised multicentre study involved 2340 primary care physicians, 72 rheumatologists, 4 university hospitals and 4 rheumatology centres in 4 German Federal States. The two coprimary endpoints (time to diagnosis and screening performance of primary care physicians) were evaluated for early versus late implementation phase. Additionally, time to diagnosis and secondary endpoints (decrease of disease activity, increase in quality of life and overall well-being, improvement of fatigue, depression, functional ability, and work ability, reduction in drug and medical costs and hospitalisation) were compared with a reference cohort of the German Rheumatism Research Centre (DRFZ) reflecting standard care. RESULTS: A total of 7049 patients were enrolled in the coordination centres and 1537 patients were diagnosed with a rheumatic disease and consented to further participation. A follow-up consultation after 1 year was realised in 592 patients. The time to diagnosis endpoint and the secondary endpoints were met. In addition, the calculation of cost-effectiveness shows that Rheuma-VOR has a dominant cost-benefit ratio compared with standard care. DISCUSSION: Rheuma-VOR has shown an improvement in rheumatological care, patient-reported outcome parameters and cost savings by coordinating the cooperation of primary care physicians, rheumatologists and patients, in a nationwide approach.

EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2023 update.

OBJECTIVE: New modes of action and more data on the efficacy and safety of existing drugs in psoriatic arthritis (PsA) required an update of the EULAR 2019 recommendations for the pharmacological treatment of PsA. METHODS: Following EULAR standardised operating procedures, the process included a systematic literature review and a consensus meeting of 36 international experts in April 2023. Levels of evidence and grades of recommendations were determined. RESULTS: The updated recommendations comprise 7 overarching principles and 11 recommendations, and provide a treatment strategy for pharmacological therapies. Non-steroidal anti-inflammatory drugs should be used in monotherapy only for mild PsA and in the short term; oral glucocorticoids are not recommended. In patients with peripheral arthritis, rapid initiation of conventional synthetic disease-modifying antirheumatic drugs is recommended and methotrexate preferred. If the treatment target is not achieved with this strategy, a biological disease-modifying antirheumatic drug (bDMARD) should be initiated, without preference among modes of action. Relevant skin psoriasis should orient towards bDMARDs targeting interleukin (IL)-23p40, IL-23p19, IL-17A and IL-17A/F inhibitors. In case of predominant axial or entheseal disease, an algorithm is also proposed. Use of Janus kinase inhibitors is proposed primarily after bDMARD failure, taking relevant risk factors into account, or in case bDMARDs are not an appropriate choice. Inflammatory bowel disease and uveitis, if present, should influence drug choices, with monoclonal tumour necrosis factor inhibitors proposed. Drug switches and tapering in sustained remission are also addressed. CONCLUSION: These updated recommendations integrate all currently available drugs in a practical and progressive approach, which will be helpful in the pharmacological management of PsA.

Efficacy and safety of pharmacological treatment of psoriatic arthritis: a systematic literature research informing the 2023 update of the EULAR recommendations for the management of psoriatic arthritis.

OBJECTIVES: To obtain an overview of recent evidence on efficacy and safety of pharmacological treatments in psoriatic arthritis (PsA). METHODS: This systematic literature research (SLR) investigated the efficacy and safety of conventional synthetic (cs), biological (b) and targeted synthetic (ts) disease-modifying antirheumatic drugs (DMARDs) in patients with PsA. A systematic database search using Medline, EMBASE, Cochrane CENTRAL was conducted to identify relevant articles published since the previous update in 2019 until 28 December 2022. Efficacy was assessed in trials while for safety observational data were also considered. Adverse events of special interest were infections (including herpes zoster, influenza and tuberculosis), malignancies, major adverse cardiovascular events, venous thromboembolisms, liver disease, laboratory changes and psychiatric adverse events. No meta-analyses were performed. RESULTS: For efficacy, of 3946 articles screened, 38 articles (30 trials) were analysed. The compounds investigated included csDMARDs (leflunomide, methotrexate), bDMARDs inhibiting IL17 (bimekizumab, brodalumab, ixekizumab, izokibep, secukinumab,), IL-23 (guselkumab, risankizumab, tildrakizumab), IL-12/23 (ustekinumab) as well as TNF (adalimumab, certolizumab-pegol, etanercept, infliximab, golimumab) and Janus Kinase inhibitors (JAKi) (brepocitinib, deucravacitinib, tofacitinib, upadacitinib). The compounds investigated were efficacious in improving signs and symptoms of PsA, improving physical functioning and quality of life. For safety, 2055 abstracts were screened, and 24 articles analysed: 15 observational studies and 9 long-term follow-ups of trials, assessing glucocorticoids, TNFi, IL-17i, JAKi, IL-12/23i and PDE4i (apremilast). Safety indicators were generally coherent with the previous SLR in 2019. CONCLUSION: The results of this SLR informed the task force responsible for the 2023 update of the European Alliance of Associations for Rheumatology recommendations for pharmacological management of PsA.

Janus kinase inhibitors and tumour necrosis factor inhibitors show a favourable safety profile and similar persistence in rheumatoid arthritis, psoriatic arthritis and spondyloarthritis: real-world data from the BIOBADASER registry.

OBJECTIVES: To compare the safety of Janus kinase inhibitors (JAKi) with that of tumour necrosis factor inhibitors (TNFi) and determine drug persistence among patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA). METHODS: We analysed data from patients included in BIOBADASER 3.0 and treated with JAKi or TNFi from 2015 to 2023 and estimated the incidence rate ratio (IRR) of adverse events and persistence. RESULTS: A total of 6826 patients were included. Of these, 52% had RA, 25% psoriatic arthritis and 23% axial SpA. Treatment was with TNFi in 86%. The mean duration of treatment was 2.2±2.0 years with TNFi versus 1.8±1.5 with JAKi. JAKis were prescribed in older patients with longer term disease, greater comorbidity and later treatment lines and more frequently as monotherapy. The IRR of all infections and gastrointestinal events was higher among patients with RA treated with JAKi. Drug persistence at 1, 2 and 3 years was 69%, 55% and 45% for TNFi and 68%, 54% and 45% for JAKi. Multivariate regression models showed a lower probability of discontinuation for JAKi (HR=0.85; 95% CI 0.78-0.92) and concomitant conventional synthetic disease-modifying antirheumatic drugs (HR=0.90; 95% CI 0.84-0.96). The risk of discontinuation increased with glucocorticoids, comorbidities, greater disease activity and later treatment lines. CONCLUSIONS: Infections, herpes zoster and gastrointestinal adverse events in patients with RA tended to be more frequent with JAKi. However, prognosis was poor in patients receiving JAKi. Persistence was similar for TNFi and JAKi, although factors associated with discontinuation differed by diagnostic group.

Power Doppler signal at the enthesis and bone erosions are the most discriminative OMERACT ultrasound lesions for SpA: results from the DEUS (Defining Enthesitis on Ultrasound in Spondyloarthritis) multicentre study.

OBJECTIVES: To assess, in spondyloarthritis (SpA), the discriminative value of the Outcome Measures in Rheumatology (OMERACT) ultrasound lesions of enthesitis and their associations with clinical features in this population. METHODS: In this multicentre study involving 20 rheumatology centres, clinical and ultrasound examinations of the lower limb large entheses were performed in 413 patients with SpA (axial SpA and psoriatic arthritis) and 282 disease controls (osteoarthritis and fibromyalgia). 'Active enthesitis' was defined as (1) power Doppler (PD) at the enthesis grade ≥1 plus entheseal thickening and/or hypoechoic areas, or (2) PD grade >1 (independent of the presence of entheseal thickening and/or hypoechoic areas). RESULTS: In the univariate analysis, all OMERACT lesions except enthesophytes/calcifications showed a significant association with SpA. PD (OR=8.77, 95% CI 4.40 to 19.20, p<0.001) and bone erosions (OR=4.75, 95% CI 2.43 to 10.10, p<0.001) retained this association in the multivariate analysis. Among the lower limb entheses, only the Achilles tendon was significantly associated with SpA (OR=1.93, 95% CI 1.30 to 2.88, p<0.001) in the multivariate analyses. Active enthesitis showed a significant association with SpA (OR=9.20, 95% CI 4.21 to 23.20, p<0.001), and unlike the individual OMERACT ultrasound lesions it was consistently associated with most clinical measures of SpA disease activity and severity in the regression analyses. CONCLUSIONS: This large multicentre study assessed the value of different ultrasound findings of enthesitis in SpA, identifying the most discriminative ultrasound lesions and entheseal sites for SpA. Ultrasound could differentiate between SpA-related enthesitis and other forms of entheseal pathology (ie, mechanical enthesitis), thus improving the assessment of entheseal involvement in SpA.

Male patients with inflammatory joint diseases are less likely than controls to be childless: results from a Norwegian population-based cohort study of 10 865 patients.

OBJECTIVES: To investigate the number of children per man and the proportion of childless men as a proxy of fertility in a national cohort of men with inflammatory joint diseases (IJDs), compared with matched controls from the general population. METHODS: This is a nationwide, population-based retrospective cohort study. Male patients with IJDs (n = 10 865) in the Norwegian Arthritis Registry were individually matched 1:5 on birth year and county of residence with men without IJDs obtained from the National Population Register (n = 54 325). Birth data were obtained from the Medical Birth Registry of Norway. We compared the mean number of children per man and the proportion of childless men and analysed the impact of age and year of diagnosis. RESULTS: The mean number of children per man in the patient group was 1.80 versus 1.69 in the comparison group (p <0.001), and 21% of the patients in the patient group were childless versus 27% in the comparison group (p <0.001). The finding of less childlessness and higher number of children per man remained consistent across age at diagnosis, except for those diagnosed at age 0-19 years. The difference in childlessness was most pronounced for men diagnosed after year 2000, especially when diagnosed at 30-39 years of age (22% vs 32%, p<0.001). CONCLUSION: In this large cohort study we found that patients with IJD have a higher number of children and are less likely to be childless compared with controls. Factors associated with developing or having an IJD might influence fertility and this requires further investigation.

Treatment of early oligoarticular psoriatic arthritis with apremilast: primary outcomes at week 16 from the FOREMOST randomised controlled trial.

OBJECTIVES: Oligoarticular psoriatic arthritis (PsA) is frequent but rarely studied. The objective was to assess the efficacy of apremilast in early oligoarticular PsA. METHODS: FOREMOST (NCT03747939) was a phase 4 multicentre, randomised, double-blind, placebo-controlled trial. Patients had early (symptom duration ≤5 years) oligoarticular PsA (>1 but ≤4 swollen and >1 but ≤4 tender joints; 2-8 total active joints). Patients were randomised 2:1 to apremilast 30 mg two times per day or placebo for 24 weeks, with an early escape at week 16. The primary endpoint was the proportion of patients at week 16 who achieved minimal disease activity (MDA)-Joints (modification of MDA mandating ≤1 swollen joint and ≤1 tender joint) based on sentinel joints (those affected at baseline) with a combination of non-responder imputation and multiple imputations. Exploratory analysis assessed all joints. RESULTS: Of 308 patients randomised (apremilast: n=203; placebo: n=105), mean (SD) PsA duration was 9.9 (10.2) months, mean (SD) age was 50.9 (12.5) years and 39.9% of patients were using a conventional synthetic disease-modifying antirheumatic drug. MDA-Joints (sentinel joints (primary endpoint) and all joints) were achieved by significantly more patients with apremilast (33.9% and 21.3%) vs placebo (16.0% and 7.9%) at week 16 (p=0.0008 and nominal p=0.0028, respectively). Greater improvements in patient-reported outcomes, clinical disease activity and skin involvement were also seen with apremilast versus placebo. CONCLUSIONS: FOREMOST is the first randomised controlled trial designed for early oligoarticular PsA and showed apremilast improves clinical and patient-reported outcomes. This trial may inform the optimal management of PsA in these patients. TRIAL REGISTRATION NUMBER: NCT03747939.

Unmet need in rheumatology: reports from the Advances in Targeted Therapies meeting, 2023.

The Advances in Targeted Therapies meets annually, convening experts in the field of rheumatology to both provide scientific updates and identify existing scientific gaps within the field. To review the major unmet scientific needs in rheumatology. The 23rd annual Advances in Targeted Therapies meeting convened with more than 100 international basic scientists and clinical researchers in rheumatology, immunology, infectious diseases, epidemiology, molecular biology and other specialties relating to all aspects of immune-mediated inflammatory diseases. We held breakout sessions in five rheumatological disease-specific groups including: rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthritis (axSpa), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and vasculitis, and osteoarthritis (OA). In each group, experts were asked to identify and prioritise current unmet needs in clinical and translational research. An overarching theme across all disease states is the continued need for clinical trial design innovation with regard to therapeutics, endpoint and disease endotypes. Within RA, unmet needs comprise molecular classification of disease pathogenesis and activity, pre-/early RA strategies, more refined pain profiling and innovative trials designs to deliver on precision medicine. Continued scientific questions within PsA include evaluating the genetic, immunophenotypic, clinical signatures that predict development of PsA in patients with psoriasis, and the evaluation of combination therapies for difficult-to-treat disease. For axSpA, there continues to be the need to understand the role of interleukin-23 (IL-23) in pathogenesis and the genetic relationship of the IL-23-receptor polymorphism with other related systemic inflammatory diseases (eg, inflammatory bowel disease). A major unmet need in the OA field remains the need to develop the ability to reliably phenotype and stratify patients for inclusion in clinical trials. SLE experts identified a number of unmet needs within clinical trial design including the need for allowing endpoints that reflect pharmacodynamic/functional outcomes (eg, inhibition of type I interferon pathway activation; changes in urine biomarkers). Lastly, within SSc and vasculitis, there is a lack of biomarkers that predict response or disease progression, and that allow patients to be stratified for therapies. There remains a strong need to innovate clinical trial design, to identify systemic and tissue-level biomarkers that predict progression or response to therapy, endotype disease, and to continue developing therapies and therapeutic strategies for those with treatment-refractory disease. This document, based on expert consensus, should provide a roadmap for prioritising scientific endeavour in the field of rheumatology.

Two-sample Mendelian Randomization to evaluate the causal relationship between inflammatory arthritis and female-specific cancers.

BACKGROUND: There is evidence that inflammatory arthritis in the form of ankylosing spondylitis (AS), psoriatic arthritis (PsA), and rheumatoid arthritis are both positively and negatively associated with certain female-specific cancers. However, the study results are very heterogeneous. METHODS: Based on up to 375,814 European women, we performed an iterative two-sample Mendelian randomization to assess causal effects of the occurrence of the inflammatory arthritis on the risk of female-specific cancer in form of breast, endometrial, and ovarian cancer sites as well as their subtypes. Evidence was strengthened by using similar exposures for plausibility or by replication with a subsequent meta-analysis. P-values were Bonferroni adjusted. RESULTS: Genetic liability to AS was associated with ovarian cancer (OR = 1.03; 95% CI: [1.01; 1.04]; [Formula: see text]=0.029) and liability to PsA with breast cancer (OR = 1.02; CI: [1.01; 1.04]; [Formula: see text]=0.002). Subgroup analyses revealed that the high-grade serous ovarian cancer (OR = 1.04; CI: [1.02; 1.06]; [Formula: see text]=0.015) and the ER- breast cancer (OR = 1.04; CI: [1.01; 1.07]; [Formula: see text]=0.118) appeared to drive the observed associations, respectively. No further associations were found between the remaining inflammatory arthritis phenotypes and female-specific cancers. CONCLUSIONS: This study suggests that AS is a risk factor for ovarian cancer, while PsA is linked to an increased breast cancer risk. These results are important for physicians caring women with inflammatory arthritis to advise their patients on cancer screening and preventive measures.

Global and regional epidemiology of psoriatic arthritis in patients with psoriasis: A comprehensive systematic analysis and modelling study.

OBJECTIVES: To provide a comprehensive analysis and modelling of the global epidemiology of psoriatic arthritis (PsA) in patients with psoriasis. METHODS: We reviewed and analysed PsA epidemiology studies over the past 45 years. A Bayesian hierarchical linear mixed model was developed to provide comprehensive age- and sex-specific epidemiologic estimates in different countries and regions. RESULTS: Three hundred and sixty-three studies were systematically reviewed. The incidence of PsA in patients with psoriasis varied from 2.31 per 1000 person-years in the United Kingdom to 74.00 per 1000 person-years in several Western European countries. The global prevalence of PsA in patients with psoriasis is estimated to be 17.58% (3.33%, 43.69%). Regionally, the overall prevalence of PsA in patients with psoriasis varies from 7.62% (4.18%, 12.28%) in Australasia to 26.59% (18.89%, 35.76%) in North America. The Caribbean and Central Latin America also have relatively high prevalence and are estimated at 23.14% (14.06%, 35.17%) and 22.81% (14.36%, 32.25%), respectively. The prevalence of PsA is higher in adults than children (23.93% vs 8.59%) and also slightly higher in females than males (19.14% vs 16.01%). CONCLUSIONS: This study provides valuable insights into the global epidemiology of PsA. It also serves as a useful resource for researchers in areas lacking relevant studies. These findings have important implications for clinicians managing the course of PsA and for health policymakers in resource allocation.

IL-23 induces CLEC5A+ IL-17A+ neutrophils and elicit skin inflammation associated with psoriatic arthritis.

IL-23-activation of IL-17 producing T cells is involved in many rheumatic diseases. Herein, we investigate the role of IL-23 in the activation of myeloid cell subsets that contribute to skin inflammation in mice and man. IL-23 gene transfer in WT, IL-23RGFP reporter mice and subsequent analysis with spectral cytometry show that IL-23 regulates early innate immune events by inducing the expansion of a myeloid MDL1+CD11b+Ly6G+ population that dictates epidermal hyperplasia, acanthosis, and parakeratosis; hallmark pathologic features of psoriasis. Genetic ablation of MDL-1, a major PU.1 transcriptional target during myeloid differentiation exclusively expressed in myeloid cells, completely prevents IL-23-pathology. Moreover, we show that IL-23-induced myeloid subsets are also capable of producing IL-17A and IL-23R+MDL1+ cells are present in the involved skin of psoriasis patients and gene expression correlations between IL-23 and MDL-1 have been validated in multiple patient cohorts. Collectively, our data demonstrate a novel role of IL-23 in MDL-1-myelopoiesis that is responsible for skin inflammation and related pathologies. Our data open a new avenue of investigations regarding the role of IL-23 in the activation of myeloid immunoreceptors and their role in autoimmunity.

Tofacitinib restores psoriatic arthritis fibroblast-like synoviocytes function via autophagy and mitochondrial quality control modulation.

OBJECTIVES: To evaluate the in vitro effect of tofacitinib on autophagy activity of psoriatic arthritis (PsA) fibroblast-like synoviocytes (FLS), and to confirm its activity on inflammatory and invasive properties of FLS and synovial cells, deepening the impact on mitochondrial function. METHODS: FLS, peripheral blood mononuclear cells (PBMCs), and synovial cells from active PsA patients were cultured with tofacitinib 1 µM or vehicle control for 24 h. Autophagy was measured by Western blot and by fluorescence microscopy. Chemokines/cytokines released into culture supernatants were quantified by ELISA, while invasive properties of FLS by migration assays. Specific mitochondrial probes were adopted to measure intracellular reactive oxygen species (ROS), mitochondrial potential, morphology, turnover and mitophagy. Oxygen consumption rate (OCR), reflecting oxidative phosphorylation, was quantified using the Seahorse technology. Differences were determined by adopting the non-parametric Wilcoxon signed rank test. RESULTS: 18 patients with moderately-to-severely active PsA were enrolled. Tofacitinib significantly increased the levels of the autophagy markers LC3-II and ATG7 in PsA FLS compared to vehicle control, suggesting an increase in spontaneous autophagy activity; no effect was highlighted in PBMCs and synovial cells cultures. Tofacitinib reduced migration properties of PsA FLS, and reduced MCP-1 and IL-6 release into FLS and synovial cells cultures supernatants. Furthermore, tofacitinib decreased intracellular ROS production, increased basal OCR, ATP production and maximal respiratory capacity, and enhanced mitophagy and mitochondrial turnover. CONCLUSIONS: The JAK inhibitor tofacitinib reduces the pro-invasive and pro-inflammatory properties of PsA FLS. Autophagy induction and mitochondrial quality control modulation by tofacitinib might contribute to FLS function restoration.

Treatment of psoriasis with different classes of biologics reduces the likelihood of peripheral and axial psoriatic arthritis development.

OBJECTIVE: To assess the potential role of biological treatment for psoriasis (PsO) in reducing the likelihood of psoriatic arthritis (PsA), through a detailed analysis that considered the different historical phases in the PsA management, the different biologics classes, and the different patterns of articular involvement. METHODS: A monocentric cohort of 1023 PsO patients underwent a rheumatologic assessment in which clinical and therapeutic data were recorded. Chi-squared test and multivariate logistic regression analysis (adjusted for the main PsA risk factors) were performed to compare the likelihood of PsA development in different treatment groups. RESULTS: The PsA prevalence in PsO patients treated at least once with biologics was significantly lower than in patients never treated with biologics (8.9% vs 26.1%, p< 0.001). In multivariate analysis, a significantly (p< 0.01) lower likelihood of PsA development in biologic-treated patients was confirmed in the whole cohort (adjOR 0.228), as well as in the subgroups of patients with PsO onset after 2005 (adjOR 0.264) and after 2014 (adjOR 0.179). Separately analysing the different biologics classes, both the TNF (adjOR 0.206), IL-17 (adjOR 0.051) and IL-23 or 12/23 (adjOR 0.167) inhibitors were significantly (p< 0.01) associated with a lower likelihood of PsA development. Finally, patients treated with biologics had a significantly (p< 0.04) lower prevalence of both pure peripheral PsA (adjOR 0.182) and peripheral PsA with axial involvement (adjOR 0.115). CONCLUSIONS: This study provides meaningful and concordant evidence supporting the significant role of different classes of biologics in reducing the likelihood of peripheral and axial PsA development.

Racial and ethnic determinants of psoriatic arthritis phenotypes and disease activity.

OBJECTIVE: Individuals of racially and ethnically diverse backgrounds are underrepresented in psoriatic arthritis (PsA) research/clinical trials, despite evidence that their disease presentation, severity and course may be distinct. Here we aim to describe how race, ethnicity and other socioeconomic factors inform disease characteristics in PsA. METHODS: 817 consecutive patients with PsA from a large, diverse metropolitan area, were enrolled in an observational, longitudinal registry. Demographics, medical history, medication use, and psoriatic disease phenotype and activity were all recorded and analyzed. RESULTS: The population was 77.4% non-Hispanic White, 2.2% Black, 7.1% Asian, and 9.9% identified as other races or multiracial, and 11.8% identified as Hispanic. Hispanic and non-White individuals had higher tender joint counts (p= 0.033) with similar swollen joint counts (p= 0.308) and medication use (p= 0.171). They also had high rates of radiographic axial disease. Hispanic individuals were significantly more likely to have higher tender joint counts (p= 0.029), higher RAPID3 scores (p= 0.004), and moderate-severe psoriasis (p= 0.010) compared with non-Hispanic White individuals. CONCLUSION: In this diverse cohort, 22.6% of patients identified as underrepresented racial and/or ethnic groups, mostly Asian or Hispanic. Despite similar swollen joint counts and medication use, non-white individuals have higher tender joint counts compared with white individuals. Phenotypically, they also were more likely to have radiographic axial involvement. These findings may reflect differences in PsA presentation, experience and outcomes in individuals of various racial and ethnic groups, which need to be taken into consideration in clinical care and research design.