Identification of connective tissue disease autoantibodies and a novel autoantibody anti-annexin A11 in patients with "idiopathic" interstitial lung disease.

BACKGROUND: Autoantibodies are a hallmark feature of Connective Tissue Diseases (CTD). Their presence in patients with idiopathic interstitial lung disease (ILD) may suggest covert CTD. We aimed to determine the prevalence of CTD autoantibodies in patients diagnosed with idiopathic ILD. METHODS: 499 patient sera were analysed: 251 idiopathic pulmonary fibrosis (IPF), 206 idiopathic non-specific interstitial pneumonia (iNSIP) and 42 cryptogenic organising pneumonia (COP). Autoantibody status was determined by immunoprecipitation. RESULTS: 2.4% of IPF sera had a CTD-autoantibody compared to 10.2% of iNSIP and 7.3% of COP. 45% of autoantibodies were anti-synthetases. A novel autoantibody targeting an unknown 56 kDa protein was found in seven IPF patients (2.8%) and two NSIP (1%) patients. This was characterised as anti-annexin A11. CONCLUSION: Specific guidance on autoantibody testing and interpretation in patients with ILD could improve diagnostic accuracy. Further work is required to determine the clinical significance of anti-annexin A11.

Systemic sclerosis and cancer in the UK: An epidemiological analysis using the Clinical Practice Research Datalink.

BACKGROUND: Cancer can cause mortality in systemic sclerosis (SSc). We investigated the association between cancer and SSc using the Clinical Practice Research Datalink (CPRD). METHODS: A validated case-ascertainment strategy identified SSc patients in the CPRD. A cohort study design examined cancer occurrence following SSc, with SSc patients matched to six non-SSc comparators by age, sex and GP-practice. Prevalent and incident cases of SSc were analysed separately. Descriptive statistics and Cox analyses determined hazard ratios for cancer occurrence. A case-control study (matched 1:6) examined cancer occurrence prior to SSc. RESULTS: From 10.1 million individuals in CPRD, 1,588 of cases of SSc were identified. Two hundred and six cancers followed SSc diagnosis (116 in prevalent and 90 in incident cohort). Commonest cancers were mucocutaneous (4.5%), lung (2.1%) and breast (1.9%). The proportion of SSc patients developing cancer was significantly higher than non-SSc in both incident (11.2% vs 9.7%, p= 0.02) and prevalent cohorts (14.8% vs 12.1%, p= 0.03); particularly for lung cancer (2.6% vs 0.9% in prevalent cohort, p< 0.001). Overall incidence of cancer in the SSc groups was 17.6/1000 person years, compared with 13.9/1000 person years in non-SSc group. The adjusted hazard ratios for cancer was 1.41 (95% CI 1.14-1.75) and 1.32 (95% CI 1.04-1.67) for prevalent and incident SSc respectively. No increased risk of cancer prior to SSc diagnosis was identified in case-control study. CONCLUSION: We have identified an increased risk of cancer diagnosis following, but not before, SSc diagnosis. Our findings could support screening recommendations for cancer in SSc.

Effectiveness of sequential lines of biologic and targeted small-molecule drugs in psoriatic arthritis: a systematic review.

OBJECTIVE: To assess current evidence for effectiveness of sequential lines of biologic and targeted small-molecule disease-modifying anti-rheumatic drugs (b/tsDMARDs) when used beyond first-line for psoriatic arthritis (PsA). METHODS: A systematic search of the literature (Medline, Embase, bibliographic searches) was undertaken (October and December 2022) to find studies meeting the criteria of assessing effectiveness of b/tsDMARDs beyond first-line in adults with PsA (PROSPERO CRD42022365298). Risk of bias assessment was undertaken (ROBINS-I/Cochrane RoB2). RESULTS: Of 2666 abstracts identified and following a full text review of 177 psoriatic disease studies, 12 manuscripts and two abstracts were eligible. Of the 12 manuscripts, 11 were observational and one was a sub-analysis of a RCT (n = 16 081: average age 49.5 years, female 53.3%). Two abstracts (n = 7186) were included. All studies comparing first- and second-line (three studies) found a reduced response in second-line. On average, DAPSA remission (most reported outcome, eight studies) was achieved in 26%, 19% and 10% first-, second- and third-line TNFi, and 22%, 13% and 11% first-, second- and third-line other bDMARDs, respectively. Responses varied to third-line bDMARDs; four studies found comparable second- and third-line responses, five studies found diminishing responses in sequential lines. CONCLUSION: Predominantly observational studies, inherently at high risk of bias, indicate bDMARDs can be effective to third-line in PsA, but that response is reduced after first line. There is very limited data for more advanced lines of b/tsDMARD. Prospective studies are required to better understand clinical response to advanced lines of treatment in PsA.

The comparative performance of three screening questionnaires for psoriatic arthritis in a primary care surveillance study.

OBJECTIVES: The objective of this study was to compare the performance of three PsA screening questionnaires in a primary care psoriasis surveillance study. METHODS: Participants with psoriasis, and not known to have PsA, were identified from general practice databases and invited to attend a secondary care centre for a clinical assessment. The three patient-completed screening questionnaires (PEST, CONTEST and CONTESTjt) were administered, along with other patient-reported measures, and a clinical examination of skin and joints was performed. Participants who demonstrated signs of inflammatory arthritis suggestive of PsA were referred, via their GP, for a further assessment in a secondary care rheumatology clinic. RESULTS: A total of 791 participants attended the screening visit, and 165 participants were judged to have signs and symptoms of inflammatory arthritis, of which 150 were referred for assessment. Of these, 126 were seen and 48 were diagnosed with PsA. The results for each questionnaire were as follows: PEST: sensitivity 0.625 (95% CI 0.482, 0.749), specificity 0.757 (0.724, 0.787); CONTEST: sensitivity 0.604 (0.461, 0.731), specificity 0.768 (0.736, 0.798); and CONTESTjt: sensitivity 0.542 (0.401, 0.676), specificity 0.834 (0.805, 0.859). CONTESTjt demonstrated marginally superior specificity to PEST, though the area under the ROC curve was similar for all three instruments. CONCLUSION: Minimal differences between the three screening questionnaires were found in this study, and no preferred questionnaire is indicated by these results. The choice of which instrument to choose will depend on other factors, such as simplicity and low patient burden.

Enhanced surveillance for the detection of psoriatic arthritis in a UK primary care psoriasis population: results from the TUDOR trial.

BACKGROUND: Our objective was to determine whether early detection of undiagnosed psoriatic arthritis (PsA) in a primary care psoriasis population improves outcome in physical function at 24 months post-registration. METHODS: A multicentre, prospective, parallel group cluster randomised controlled trial in patients with psoriasis was conducted. Participants with suspected inflammatory arthritis on screening were referred for an assessment of PsA (enhanced surveillance (ES) arm: at baseline, 12 and 24 months; standard care (SC) arm: at 24 months). The primary outcome measure was the Health Assessment Questionnaire Disability Index (HAQ-DI) at 24 months post registration in participants diagnosed with PsA. RESULTS: A total of 2225 participants across 135 GP practices registered: 1123 allocated to ES and 1102 to SC. The primary analysis population consisted of 87 participants with a positive diagnosis of PsA: 64 in ES, 23 in SC. The adjusted odds ratio (OR) for achieving a HAQ-DI score of 0 at 24 months post registration in ES compared with SC was 0.64 (95% CI (0.17, 2.38)), and the adjusted OR of achieving a higher (non-zero) HAQ-DI score at 24 months post registration in ES relative to SC arm was 1.12 (95% CI: 0.67, 1.86), indicating no evidence of a difference between the two treatment groups (p= 0.66). CONCLUSION: The trial was underpowered for demonstrating the prespecified treatment effect; in patients with psoriasis there was no evidence that early diagnosis of PsA by ES in primary care changes physical function at 24 months compared with SC. CLINICAL TRIAL REGISTRATION: The TUDOR trial is registered as ISRCTN38877516.

Assessing the sensitivity and specificity of myositis-specific and associated autoantibodies: a sub-study from the MyoCite cohort.

OBJECTIVES: Myositis-specific and associated autoantibodies are important biomarkers in routine clinical use. We assessed local testing performance for myositis autoantibodies by comparing line immunoassay (LIA) to protein radio-immunoprecipitation and identifying clinical characteristics associated with each myositis autoantibody in the MyoCite cohort. METHODS: Serum samples from patients within the MyoCite cohort, a well-characterized retro-prospective dataset of adult and juvenile idiopathic inflammatory myopathy (IIM) patients in Lucknow, India (2017-2020), underwent LIA at Sanjay Gandhi Postgraduate Institute of Medical Science (SGPGIMS), Lucknow. Immunoprecipitation of 147 IIM patients' serum samples (125 adult-onset, 22 juvenile-onset) was conducted at the University of Bath, with researchers blind to LIA results. LIA performance was assessed against immunoprecipitation as the reference standard, measuring sensitivity, specificity and inter-rater agreement. Univariate and multivariate logistic regression determined clinical associations for specific myositis-specific autoantibodies. RESULTS: Immunoprecipitation identified myositis autoantibodies in 56.5% (n = 83) of patient samples, with anti-Jo1 (n = 16; 10.9%) as the most common, followed by anti-MDA5 (n = 14, 9.5%). While LIA showed good agreement for anti-Jo1, anti-PL7 and anti-PL12 (Cohen's κ 0.79, 0.83 and 1, respectively), poor agreement was observed in other subgroups, notably anti-TIF1γ (Cohen's κ 0.21). Strongly positive samples, especially in myositis-specific autoantibodies, correlated more with immunoprecipitation results. Overall, 59 (40.1%) samples exhibited non-congruence on LIA and immunoprecipitation, and κ values for LIAs for anti-TIF1γ, anti-Ku, anti-PmScl, anti-Mi2 and anti-SAE ranged between 0.21 and 0.60. CONCLUSION: While LIA reliably detected anti-Jo1, anti-PL7, anti-PL12, anti-MDA5 and anti-NXP-2, it also displayed false positives and negatives. Its effectiveness in detecting other autoantibodies, such as anti-TIF1γ, was poor.

Incidence of Psoriatic Arthritis in a Primary Care Psoriasis Population in the United Kingdom.

OBJECTIVE: To determine the annual incidence of psoriatic arthritis (PsA) in a United Kingdom primary care population with preexisting psoriasis (PsO) followed prospectively over 2 years after excluding baseline prevalence of existing disease. METHODS: Total Burden of Psoriasis (TUDOR; ISRCTN registry: ISRCTN38877516) was a multicenter, prospective, 2-arm parallel-group cluster randomized controlled trial of the early identification of PsA by annual rheumatological assessment (termed "Enhanced Surveillance") vs standard care in people with PsO identified in primary care. Incidence of PsA is reported at 12 months and 24 months using patients from the Enhanced Surveillance arm, which allows for the exclusion of patients with prevalent PsA at baseline. RESULTS: Fourteen of 511 participants attending a 12-month screen developed PsA over that interval, giving an incidence of 2.74/100 patient-years (PYs; 95% CI 1.32-4.16). Another 7/444 participants attending the 24-month visit developed PsA, giving an incidence of 1.58/100 PYs (95% CI 0.42-2.74). The combined incidence over 2 years was 2.20/100 PYs (95% CI 1.27-3.13). CONCLUSION: The estimated annual incidence of PsA over a 2-year period was 2.20/100 PYs, which is in keeping with studies including clinical assessment rather than relying on health records alone. Extended follow-up of the TUDOR cohort with accrual of larger numbers of incident cases will allow risk factors for PsA to be explored in more depth.

An update on myositis autoantibodies and insights into pathogenesis.

Myositis-specific autoantibodies (MSAs) are hallmarks of idiopathic inflammatory myopathies (IIMs) and have become increasing valuable in disease diagnosis, phenotyping, and classification. In addition to their clinical utility, emerging data, including findings from several animal studies, suggest that MSAs and autoreactive T cells substantially contribute to the etiopathogenesis of IIMs. This review aims to provide an updated perspective on myositis autoantibodies by focusing on relevant clinical and translational studies.

Agreement between local and central anti-synthetase antibodies detection: results from the Classification Criteria of Anti-Synthetase Syndrome project biobank.

OBJECTIVES: The CLASS (Classification Criteria of Anti-Synthetase Syndrome) project is a large international multicentre study that aims to create the first data-driven anti-synthetase syndrome (ASSD) classification criteria. Identifying anti-aminoacyl tRNA synthetase antibodies (anti-ARS) is crucial for diagnosis, and several commercial immunoassays are now available for this purpose. However, using these assays risks yielding false-positive or false-negative results, potentially leading to misdiagnosis. The established reference standard for detecting anti-ARS is immunoprecipitation (IP), typically employed in research rather than routine autoantibody testing. We gathered samples from participating centers and results from local anti-ARS testing. As an "ad-interim" study within the CLASS project, we aimed to assess how local immunoassays perform in real-world settings compared to our central definition of anti-ARS positivity. METHODS: We collected 787 serum samples from participating centres for the CLASS project and their local anti-ARS test results. These samples underwent initial central testing using RNA-IP. Following this, the specificity of ARS was reconfirmed centrally through ELISA, line-blot assay (LIA), and, in cases of conflicting results, protein-IP. The sensitivity, specificity, positive likelihood ratio and positive and negative predictive values were evaluated. We also calculated the inter-rater agreement between central and local results using a weighted κ co-efficient. RESULTS: Our analysis demonstrates that local, real-world detection of anti-Jo1 is reliable with high sensitivity and specificity with a very good level of agreement with our central definition of anti-Jo1 antibody positivity. However, the agreement between local immunoassay and central determination of anti-non-Jo1 antibodies varied, especially among results obtained using local LIA, ELISA and "other" methods. CONCLUSIONS: Our study evaluates the performance of real-world identification of anti-synthetase antibodies in a large cohort of multi-national patients with ASSD and controls. Our analysis reinforces the reliability of real-world anti-Jo1 detection methods. In contrast, challenges persist for anti-non-Jo1 identification, particularly anti-PL7 and rarer antibodies such as anti-OJ/KS. Clinicians should exercise caution when interpreting anti-synthetase antibodies, especially when commercial immunoassays test positive for non-anti-Jo1 antibodies.

From polarity to plurality: Perceptions of COVID-19 and policy measures in England and Scotland.

AIM: The aim of this study was to uncover perspectives on the COVID-19 pandemic and the responses implemented by the UK and Scottish Governments to help control the spread of infection. Such understanding could help to inform future responses to pandemics at individual, community and national levels. METHOD: Q methodology was used to elicit perspectives from people in England and Scotland with different experiences of the pandemic including public health officials, key workers, those on furlough, those who were unvaccinated or vaccinated to different levels, those who were 'shielding' because they were at higher risk and people with different scientific expertise. Participants rank-ordered phrases about different aspects of COVID-19 according to their viewpoint. Factor analysis was then conducted in conjunction with interview material from the same respondents. RESULTS: A four-factor solution was statistically supported and was interpretable alongside the qualitative accounts of participants loading on these factors. These four perspectives are titled Dangerous and Unaccountable Leadership, Fear and Anger at Policy and Public responses, Governing Through a Crisis and Injustices Exposed. CONCLUSION: The four perspectives demonstrate plurality and nuance in views on COVID-19 and the associated policies and restrictions, going beyond a binary narrative that has been apparent in popular and social media. The four perspectives include some areas of common ground, as well as disagreement. We argue that understanding the detail of different perspectives might be used to build cohesion around policy initiatives in future. PATIENT OR PUBLIC CONTRIBUTION: The development of the statement set, which is rank-ordered by participants in a Q study, and factor interpretations were informed by views of the general public. The statement set was initially developed using existing publicly available material based on members of the general public experiencing the pandemic first hand. It was then piloted with members of the public experiencing different challenges as a result of COVID-19 and the subsequent lockdown and updated based on feedback. Finally, interpretations of the identified factors were presented publicly and edited according to their feedback.

Outcomes of children born to mothers with systemic lupus erythematosus exposed to hydroxychloroquine or azathioprine.

OBJECTIVES: HCQ and AZA are used to control disease activity and reduce risk of flare during pregnancy in patients with SLE. The aim of this study was to determine the outcomes of children born to mothers with SLE exposed to HCQ or AZA during pregnancy and breast-feeding. METHODS: Women attending UK specialist lupus clinics with children ≤17 years old, born after SLE diagnosis, were recruited to this retrospective study. Data were collected using questionnaires and from clinical record review. Factors associated with the outcomes of low birth weight and childhood infection were determined using multivariable mixed-effects logistic regression models. RESULTS: We analysed 284 live births of 199 mothers from 10 UK centres. The first pregnancies of 73.9% of mothers (147/199) were captured in the study; (60.4%) (150/248) and 31.1% (87/280) children were exposed to HCQ and AZA, respectively. There were no significant differences in the frequency of congenital malformations or intrauterine growth restriction between children exposed or not to HCQ or AZA. AZA use was increased in women with a history of hypertension or renal disease. Although AZA was associated with low birth weight in univariate models, there was no significant association in multivariable models. In adjusted models, exposure to AZA was associated with increased reports of childhood infection requiring hospital management [odds ratio 2.283 (1.003, 5.198), P = 0.049]. CONCLUSIONS: There were no significant negative outcomes in children exposed to HCQ in pregnancy. AZA use was associated with increased reporting of childhood infection, which warrants further study.

The BILAG-2004 index is associated with development of new damage in SLE.

OBJECTIVE: To determine whether BILAG-2004 index is associated with the development of damage in a cohort of SLE patients. Mortality and development of damage were examined. METHODS: This was a multicentre longitudinal study. Patients were recruited within 12 months of achieving fourth ACR classification criterion for SLE. Data were collected on disease activity, damage, SLE-specific drug exposure, cardiovascular risk factors, antiphospholipid syndrome status and death at every visit. This study ran from 1 January 2005 to 31 December 2017. Descriptive statistics were used to analyse mortality and development of new damage. Poisson regression was used to examine potential explanatory variables for development of new damage. RESULTS: A total of 273 SLE patients were recruited with total follow-up of 1767 patient-years (median 73.4 months). There were 6348 assessments with disease activity scores available for analysis. During follow-up, 13 deaths and 114 new damage items (in 83 patients) occurred. The incidence rate for development of damage was higher in the first 3 years before stabilizing at a lower rate. Overall rate for damage accrual was 61.1 per 1000 person-years (95% CI: 50.6, 73.8). Analysis showed that active disease scores according to BILAG-2004 index (systems scores of A or B, counts of systems with A and BILAG-2004 numerical score) were associated with development of new damage. Low disease activity (LDA) states [BILAG-2004 LDA and BILAG Systems Tally (BST) persistent LDA] were inversely associated with development of damage. CONCLUSIONS: BILAG-2004 index is associated with new damage. BILAG-2004 LDA and BST persistent LDA can be considered as treatment targets.

Comparison of clinical features between patients with anti-synthetase syndrome and dermatomyositis: Results from the MYONET registry.

OBJECTIVES: To compare clinical characteristics, including the frequency of cutaneous, extramuscular manifestations, and malignancy, between adults with anti-synthetase syndrome (ASyS) and dermatomyositis (DM). METHODS: Using data regarding adults from the MYONET registry, a cohort of DM patients with anti-Mi2/-TIF1É£/-NXP2/-SAE/-MDA5 autoantibodies, and a cohort of ASyS patients with anti-tRNA synthetase autoantibodies (anti-Jo1/-PL7/-PL12/-OJ/-EJ/-Zo/-KS) were identified. Patients with DM sine dermatitis or with discordant dual autoantibody specificities were excluded. Sub-cohorts of patients with ASyS with or without skin involvement were defined based on presence of DM-type rashes (heliotrope rash, Gottron's papules/sign, violaceous rash, shawl sign, V sign, erythroderma, and/or periorbital rash). RESULTS: In total 1,054 patients were included (DM, n = 405; ASyS, n = 649). In ASyS cohort, 31% (n = 203) had DM-type skin involvement (ASyS-DMskin). A higher frequency of extramuscular manifestations, including Mechanic's hands, Raynaud's phenomenon, arthritis, interstitial lung disease, and cardiac involvement differentiated ASyS-DMskin from DM (all p< 0.001), whereas higher frequency of any of four DM-type rashes: heliotrope rash (n = 248, 61% vs n = 90, 44%), violaceous rash (n = 166, 41% vs n = 57, 9%), V sign (n = 124, 31% vs n = 28, 4%), and shawl sign (n = 133, 33% vs n = 18, 3%) differentiated DM from ASyS-DMskin (all p< 0.005). Cancer-associated myositis (CAM) was more frequent in DM (n = 67, 17%) compared with ASyS (n = 21, 3%) and ASyS-DMskin (n = 7, 3%) cohorts (both p< 0.001). CONCLUSION: DM-type rashes are frequent in patients with ASyS; however, distinct clinical manifestations differentiate these patients from classical DM. Skin involvement in ASyS does not necessitate increased malignancy surveillance. These findings will inform future ASyS classification criteria and patient management.

Proteomic analysis identifies subgroups of patients with active systemic lupus erythematosus.

OBJECTIVE: Systemic lupus erythematosus (SLE) is a clinically and biologically heterogenous autoimmune disease. We aimed to investigate the plasma proteome of patients with active SLE to identify novel subgroups, or endotypes, of patients. METHOD: Plasma was collected from patients with active SLE who were enrolled in the British Isles Lupus Assessment Group Biologics Registry (BILAG-BR). The plasma proteome was analysed using a data-independent acquisition method, Sequential Window Acquisition of All theoretical mass spectra mass spectrometry (SWATH-MS). Unsupervised, data-driven clustering algorithms were used to delineate groups of patients with a shared proteomic profile. RESULTS: In 223 patients, six clusters were identified based on quantification of 581 proteins. Between the clusters, there were significant differences in age (p = 0.012) and ethnicity (p = 0.003). There was increased musculoskeletal disease activity in cluster 1 (C1), 19/27 (70.4%) (p = 0.002) and renal activity in cluster 6 (C6) 15/24 (62.5%) (p = 0.051). Anti-SSa/Ro was the only autoantibody that significantly differed between clusters (p = 0.017). C1 was associated with p21-activated kinases (PAK) and Phospholipase C (PLC) signalling. Within C1 there were two sub-clusters (C1A and C1B) defined by 49 proteins related to cytoskeletal protein binding. C2 and C6 demonstrated opposite Rho family GTPase and Rho GDI signalling. Three proteins (MZB1, SND1 and AGL) identified in C6 increased the classification of active renal disease although this did not reach statistical significance (p = 0.0617). CONCLUSIONS: Unsupervised proteomic analysis identifies clusters of patients with active SLE, that are associated with clinical and serological features, which may facilitate biomarker discovery. The observed proteomic heterogeneity further supports the need for a personalised approach to treatment in SLE.

Policy actors' perceptions of public participation to tackle health inequalities in Scotland: a paradox?

BACKGROUND: Health inequalities are persistent and widening with transformative policy change needed. Radically shifting policy to tackle upstream causes of inequalities is likely to require public participation to provide a mandate, evidence and to address questions of co-design, implementation and acceptability. The aim of this paper is to explore perceptions among policy actors on why and how the public should be involved in policymaking for health inequalities. METHODS: In 2019-2020, we conducted exploratory, in-depth, semi-structured interviews with 21 Scottish policy actors from a range of public sector bodies and agencies and third sector organisations that work in, or across, health and non-health sectors. Data were analysed thematically and used to examine implications for the development of participatory policymaking. RESULTS: Policy actors viewed public participation in policymaking as intrinsically valuable for democratic reasons, but the main, and more challenging, concern was with how it could affect positive policy change. Participation was seen as instrumental in two overlapping ways: as evidence to improve policies to tackle health inequalities and to achieve public acceptance for implementing more transformative policies. However, our analysis suggests a paradox: whilst policy actors place importance on the instrumental value of public participation, they simultaneously believe the public hold views about health inequalities that would prevent transformative change. Finally, despite broad agreement on the need to improve public participation in policy development, policy actors were uncertain about how to make the necessary changes due to conceptual, methodological and practical challenges. CONCLUSIONS: Policy actors believe in the importance of public participation in policy to address health inequalities for intrinsic and instrumental reasons. Yet, there is an evident tension between seeing public participation as a route to upstream policies and a belief that public views might be misinformed, individualistic, short-term or self-interested and doubts about how to make public participation meaningful. We lack good insight into what the public think about policy solutions to health inequalities. We propose that research needs to shift from describing the problem to focusing more on potential solutions and outline a potential way forward to undertake effective public participation to tackle health inequalities.

Using Bayesian networks to identify musculoskeletal symptoms influencing the risk of developing psoriatic arthritis in people with psoriasis.

OBJECTIVES: The aim of this study was to explore the use of Bayesian networks (BNs) to understand the relationships between musculoskeletal symptoms and the development of PsA in people with psoriasis. METHODS: Incident cases of psoriasis were identified for 1998 to 2015 from the UK Clinical Research Practice Datalink. Musculoskeletal symptoms (identified by Medcodes) were concatenated into primary groups, each made up of several subgroups. Baseline demographics for gender, age, BMI, psoriasis severity, alcohol use and smoking status were also extracted. Several BN structures were composed using a combination of expert knowledge and data-oriented modelling based on: (i) primary musculoskeletal symptom groups; (ii) musculoskeletal symptom subgroups and (iii) demographic variables. Predictive ability of the networks using the area under the receiver operating characteristic curve was calculated. RESULTS: Over one million musculoskeletal symptoms were extracted for the 90 189 incident cases of psoriasis identified, of which 1409 developed PsA. The BN analysis yielded direct relationships between gender, BMI, arthralgia, finger pain, fatigue, hand pain, hip pain, knee pain, swelling, back pain, myalgia and PsA. The best BN, achieved by using the more site-specific musculoskeletal symptom subgroups, was 76% accurate in predicting the development of PsA in a test set and had an area under the receiver operating characteristic curve of 0.73 (95% CI: 0.70, 0.75). CONCLUSION: The presented BN model may be a useful method to identify clusters of symptoms that predict the development of PsA with reasonable accuracy. Using a BN approach, we have shown that there are several symptoms which are predecessors of PsA, including fatigue, specific types of pain and swelling.

Defining anti-synthetase syndrome: a systematic literature review.

OBJECTIVES: Anti-synthetase syndrome (ASSD) is a heterogeneous autoimmune disease characterised by multi-system involvement with a wide variety of manifestations. Validated classification criteria are necessary to improve recognition and prevent misclassification, especially given the lack of reliable and standardised autoantibody testing. We systematically reviewed the literature to analyse proposed ASSD criteria, characteristics, and diagnostic performance. METHODS: We searched PubMed and Embase databases (01/01/1984 to 06/11/2018) and the ACR and EULAR meeting abstracts (2017-2018). Sensitivities, specificities, positive, negative likelihood ratios and risk of bias were calculated for ASSD criteria and key variables reported in the literature. We performed meta-analysis when appropriate. RESULTS: We retrieved 4,358 studies. We found 85 proposed ASSD criteria from a total of 82 studies. All but one study included anti-synthetase autoantibody (ARS) positivity in the ASSD criteria. Most studies required only one ASSD feature plus anti-ARS to define ASSD (n=64, 78%), whereas 16 studies required more than one ASSD variable plus anti-ARS. The only criteria not including anti-ARS positivity required 5 ASSD clinical features. We found limited data and wide variability in the diagnostic performance of each variable and definition proposed in the literature. Given these limitations we only meta-analysed the performance of individual muscle biopsy and clinical variables in diagnosing ASSD, which performed poorly. CONCLUSIONS: The current ASSD criteria include a variety of serological, clinical, and histological features with wide variability amongst proposed definitions and the performance of these definitions has not been tested. This systematic literature review suggests the need for additional data and consensus-driven classification criteria for ASSD.

Eliciting public values on health inequalities: missing evidence for policy windows?

Background: There is a widening health divide in the UK despite health inequalities being a long-standing subject of policy and research. New types of evidence are needed. Key points for discussion: Knowledge of public values for non-health policies and their associated (non-)health outcomes is currently missing from decision-making processes. Eliciting public values using stated preference techniques can provide insights on what the general public would be willing to give-up for different distributions of (non-)health outcomes and the policies that can achieve them. To understand the role this evidence could have in decision-making processes, Kingdon's multiple streams analysis (MSA) is used as a policy lens to explore how evidence of public values could affect policy processes for ways to tackle health inequalities. Conclusions and implications: This paper outlines how evidence of public values could be elicited through the use of stated preference techniques and suggests this could facilitate the creation of policy windows for tackling health inequalities. Additionally, Kingdon's MSA helps make explicit six cross-cutting issues when generating this new form of evidence. This suggests the need to explore reasons for public values and how decision-makers would use such evidence. With an awareness of these issues, evidence on public values has the potential to support upstream policies to tackle health inequalities.

Polymyositis: is there anything left? A retrospective diagnostic review from a tertiary myositis centre.

OBJECTIVE: The current classification criteria for idiopathic inflammatory myopathy (IIM) retain PM as a major disease subgroup. However, evolution in the understanding of IIM has suggested that many of these patients could be better described as having an alternative diagnosis. In the present study, we apply the latest understanding of IIM subtyping to retrospectively review PM diagnoses in a large cohort of IIM patients. METHODS: Within a previously reported cohort of 255 patients from a UK tertiary myositis clinic, 37 patients classified as PM according to both the EULAR/ACR IIM criteria and expert opinion were identified. Clinical data and complementary tests were reviewed, and consensus decisions regarding final classification were reached in each case. RESULTS: Nine (9/37, 24.3%) patients remained classified as PM, 3.5% (9/255) of the original cohort; these PM patients were seronegative for myositis antibodies, responsive to immunosuppression, and in 4/7 (57.1%) patients where muscle biopsy was performed had HLA-1 upregulation and endomysial inflammatory infiltrates. Immune-mediated necrotizing myopathy (5/37, 13.5%) and connective tissue disease overlap myositis (7/37, 19%) were the main alternative diagnoses. The remaining patients were diagnosed as: unspecified myopathy (6/37, 16%), dermatomyositis (2/37, 5%), cancer-associated myopathy (3/37, 8.1%), and non-inflammatory myopathy (1/37, 3%, myofibrillar myopathy). Four patients (4/37, 10%) had insufficient data available to confidently reclassify. CONCLUSION: Our study confirms that PM can now be considered a rare IIM subgroup. A thorough examination, complete myositis autoantibody panel, and careful interpretation of the biopsy results is recommended to confirm the correct IIM sub-type.

Epidemiology of systemic sclerosis in the UK: an analysis of the Clinical Practice Research Datalink.

OBJECTIVES: We developed and tested a robust case ascertainment strategy within the Clinical Practice Research Datalink (CPRD), with the aim of assessing the incidence, prevalence, mortality and delay in diagnosis of SSc in the UK. METHODS: A two-stage case ascertainment strategy was devised and tested to establish a valid cohort of SSc cases within the CPRD. Incidence, prevalence and mortality statistics were analysed, alongside evaluation of the relationship between primary care codes for RP and SSc to examine diagnostic delay. RESULTS: SSc Read codes were identified in 3123 patients (from a study cohort of >10.1 million individuals). Of these, 1757 cases of SSc were identified using our case ascertainment approach. The overall incidence rate of SSc over the period between 1999 and 2017 was 10.7/million/year (95% CI: 9.9-11.4), being higher in females [17.69/million/year (95% CI: 16.32-19.07)] than in males [3.59/million/year (95% CI: 2.97-4.21)]. The overall prevalence of SSc in adults was 235.5/million (95% CI: 207.2-245.7). The mean rate of mortality was 32/1000 person-years, with an overall standardized mortality ratio of 3.51 (95% CI: 3.19-3.84). Of those with an initial code of RP prior to a Read code of SSc, 191/854 (22.4%) had a lag period of >10 years. CONCLUSION: We have developed and tested a robust case ascertainment strategy to examine the incidence, prevalence, mortality and diagnostic delay of SSc using primary care records of over 10 million UK residents. A significant lag between coding of RP and SSc in many patients suggests diagnostic delay in SSc remains an important unmet need.