IDH-mutant myeloid neoplasms are associated with seronegative rheumatoid arthritis and innate immune activation.

ABSTRACT: High prevalence of IDH mutations in seronegative rheumatoid arthritis (RA) with myeloid neoplasm, elevated 2-hydroxyglutarate, dysregulated innate immunity, and proinflammatory microenvironment suggests causative association between IDH mutations and seronegative RA. Our findings merit investigation of IDH inhibitors as therapeutics for seronegative IDH-mutated RA.

Multiple serum biomarkers associate with mortality and interstitial lung disease progression in systemic sclerosis.

OBJECTIVES: To investigate the prognostic utility of 28 serum biomarkers in systemic sclerosis (SSc), SSc-associated interstitial lung disease (SSc-ILD) and clinically relevant disease subgroups. METHODS: Participants with sera, high-resolution computed tomography, and lung function within 12 months of baseline were identified from the Australian Scleroderma Cohort Study. Baseline was the time of serum collection. 27 of the prespecified 28 serum biomarkers were analysed and biomarker associations with mortality and ILD progression were investigated in univariable and multivariable analyses, including within disease subgroups and combined with established risk factors for poorer prognosis in SSc. RESULTS: 407 participants were identified, 252 (61.9%) with SSc-ILD. The median follow up after biomarker measurement was 6.31 (3.11-9.22) years. 16 biomarkers were associated with increased mortality. High levels of VCAM-1 were most strongly associated with mortality (HR 3.55; 95%CI 2.37-5.33; p< 0.001). Five additional biomarkers had a HR > 2: SP-D (2.28, 1.57-3.31; p< 0.001), E-selectin (2.19; 1.53-3.14; p< 0.001), IL-6 (2.15 1.50-3.09; p< 0.001), MMP3 (1.42-2.95; p< 0.001) and ET-1 (2.03, 1.40-2.92; p< 0.001). 11 biomarkers were independently associated with mortality following adjustment for sex, age and baseline forced vital capacity (FVC%predicted). Three biomarkers were associated with ILD progression at one year follow up: CXCL4 (OR 2.67, 1.46-4.88; p= 0.001), MMP-1 (2.56, 1.43-4.59; p= 0.002) and ET-1 (2.18, 1.24-3.83; p= 0.007). CONCLUSION: Multiple biomarkers, especially VCAM-1, E-Selectin, SP-D and CXCL4, provide prognostic utility beyond that of established risk factors for patients with SSc.

Predictors and prognosis of pulmonary hypertension complicating interstitial lung disease in systemic sclerosis.

OBJECTIVE: To identify those with concurrent pulmonary hypertension (PH) and interstitial lung disease (ILD) in systemic sclerosis (SSc) and determine their disease severity, therapeutic approach, and survival. METHODS: Consecutive SSc patients enrolled in the Australian Scleroderma Cohort Study (ASCS) who were diagnosed on right heart catherisation with pulmonary hypertension were included. Logistic regression was used to determine the associations of ILD with PH hemodynamic parameters and therapeutic approach. Kaplan-Meier survival curves were used to estimate survival. RESULTS: Of 1,883 SSc patients, 164 (8.7%) developed incident PH over a median follow up of 4.3 (1.7-7.9) years. Of these, 43.9% had concurrent ILD at PH diagnosis (PH-ILD) and 56.1% had Group 1 PAH. Extensive ILD was present at PH diagnosis in 40.3%. Despite these distinct PH cohorts, a similar frequency of each PH cohort was treated with vasodilatory therapy at PH diagnosis, regardless of the presence or severity of ILD. The majority (87.5%) of those with extensive ILD and PH received upfront vasodilatory therapy at PH diagnosis with no difference in its tolerability or therapy cessation compared with Group 1 PAH. Although vasodilator therapy was not associated with a survival advantage in those with extensive ILD, its use was associated with an improvement in symptoms, physical function, and quality of life (QoL). CONCLUSION: Despite vasodilator therapy, survival in SSc-PH is poor, with the presence of concurrent ILD associated with worse survival. Although vasodilator therapy commenced at PH diagnosis does not portray an improved survival in PH with extensive ILD, it appears well tolerated and may improve symptoms, physical function, and QoL.

Frequency and implications of malnutrition in systemic sclerosis.

OBJECTIVES: To quantify the frequency and impact of malnutrition in systemic sclerosis (SSc), as diagnosed by the Global Leadership Initiative on Malnutrition (GLIM) criteria, based on weight loss, body mass index (BMI) and muscle atrophy. METHODS: Australian Scleroderma Cohort Study participants meeting ACR/EULAR criteria for SSc with ≥1 concurrent weight and height measurement were included. Chi-squared tests, two-sample t-tests or Wilcoxon rank-sum tests were used for between-group comparison as appropriate. Multivariable logistic regression models were used to establish the determinants of malnutrition diagnosis. Kaplan-Meier and Cox proportional hazard models were used for survival analyses, based on malnutrition diagnosis, and individual GLIM criteria (% weight loss, BMI thresholds and presence of muscle atrophy). RESULTS: In this study of 1903 participants, 43% were diagnosed with malnutrition according to GLIM criteria, of whom 33% had severe malnutrition. Participants diagnosed with malnutrition were older, and more likely to have dcSSc, higher SSc severity scores and RNA polymerase-3 positivity. Gastrointestinal (GI) involvement, multimorbidity, cardiopulmonary disease, raised inflammatory markers, hypoalbuminaemia and anaemia were more common in malnourished participants (p< 0.01). Multimorbidity (OR1.6, 95%CI1.2-2.0, p< 0.01), pulmonary arterial hypertension (OR2.1, 95%CI1.4-2.0, p< 0.01) and upper GI symptoms (OR1.6, 95%CI1.3-2.0, p< 0.01) were all associated with malnutrition.Health-related quality-of-life (HRQoL) and physical function were poorer in malnourished participants. Survival was worse in those with malnutrition after adjusting for age, sex and dcSSc (HR 1.4, 95%CI1.1-1.7, p< 0.01). CONCLUSIONS: Malnutrition is common in SSc and confers poorer survival, HRQoL and physical function.

Pharmacokinetic-pharmacodynamic modelling and simulation of methotrexate dosing in patients with rheumatoid arthritis.

AIMS: To develop a non-linear mixed-effects population pharmacokinetic and pharmacodynamic (PK-PD) model describing the change in the concentration of methotrexate polyglutamates in erythrocytes (ery-MTX-PGn with "n" number of glutamate, representing PK component) and how this relates to modified 28-joint Disease Activity Score incorporating erythrocyte sedimentation rate (DAS-28-3) for rheumatoid arthritis (RA), representing PD component. METHODS: An existing PK model was fitted to data from a study consisting of 117 RA patients. The estimation of population PK-PD parameters was performed using stochastic approximation expectation maximisation algorithm in Monolix 2021R2. The model was used to perform Monte Carlo simulations of a loading dose regimen (50mg subcutaneous methotrexate as loading doses, then 20mg weekly oral methotrexate) compared to a standard dosing regimen (10mg weekly oral methotrexate for 2 weeks, then 20mg weekly oral methotrexate). RESULTS: Every 40 nmol/L increase in ery-MTX-PG3-5 total concentration correlated with 1-unit reduction in DAS-28-3. Significant covariate effects on the therapeutic response of methotrexate included the use of prednisolone in the first 4 weeks (positive use correlated with 25% reduction in DAS-28-3 when other variables were constant) and patient age (every 10-year increase in age correlated with 3.4% increase in DAS-28-3 when other variables were constant). 4 methotrexate loading doses led to a higher percentage of patients achieving a good/moderate response compared to the standard regimen (Week 4: 87.6% vs. 39.8%; Week 10: 64.7% vs. 57.0%). CONCLUSIONS: A loading dose regimen was more likely to achieve higher ery-MTX-PG concentration and better therapeutic response after 4 weeks of methotrexate treatment.

Investigating the trajectory of functional disability in systemic sclerosis: group-based trajectory modelling of the Health Assessment Questionnaire-Disability Index.

OBJECTIVES: To identify the trajectories and clinical associations of functional disability in systemic sclerosis (SSc). METHODS: Australian Scleroderma Cohort Study (ASCS) participants meeting ACR/EULAR criteria for SSc recruited within 5 years of disease onset, with ≥2 Health Assessment Questionnaire-Disability Index (HAQ-DI) scores were included. Group based trajectory modelling (GBTM) was used to identify the number and shape of HAQ-DI trajectories. Between group comparisons were made using the chi-squared test, two-sample t-test or Wilcoxon rank-sum test as appropriate. Multiple logistic regression was used to identify features associated with trajectory group membership. Survival analyses were performed using Kaplan Meier and Cox proportional hazard modelling. RESULTS: We identified two HAQ-DI trajectory groups within 426 ASCS participants with incident SSc: low-stable disability (n=221, 52%), and high-increasing disability (n=205, 48%). Participants with high-increasing disability were older at disease onset, more likely to have diffuse SSc (dcSSc), cardiopulmonary disease, multimorbidity, digital ulcers, and gastrointestinal involvement (all p≤0.01), as was use of immunosuppression (p<0.01). Multimorbidity was associated with high-increasing trajectory group membership (OR3.1, 95%CI1.1-8.8, p=0.04); independently, multiple SSc features were also strongly associated including dcSSc (OR2.3, 95%CI1.3-4.2, p<0.01), proximal weakness (OR7.3, 95%CI2.0-27.1, p<0.01) and joint contractures (OR2.7, 95%CI1.3-5.3, p<0.01). High-increasing physical disability was associated with an almost two-fold increased risk of mortality (HR1.9, 95%CI1.0-3.8, p=0.05), and higher symptom burden. CONCLUSIONS: Two trajectories of functional disability in SSc were identified. Those with high-increasing functional disability had a distinct clinical phenotype and worse survival compared to those with low-stable functional disability. These data highlight the pervasive nature of physical disability in SSc, and its prognostic importance.

The burden and determinants of fatigue in incident and prevalent systemic sclerosis.

OBJECTIVES: To investigate the burden and clinical associations of fatigue in systemic sclerosis (SSc) as measured by FACIT-Fatigue scores. METHODS: Australian Scleroderma Cohort Study participants with ≥1 FACIT-Fatigue score were included. Participants were divided into those with incident SSc (≤5 years SSc duration at recruitment and FACIT-Fatigue score recorded within 5 years of disease onset) or prevalent SSc (first FACIT-Fatigue score recorded >5 years after SSc onset). Generalised estimating equations were used to model change in FACIT-Fatigue scores over time, expressed as an increasing (improving) or decreasing (worsening) score. RESULTS: Of 859 participants, 215 had incident SSc and 644 prevalent SSc. First-recorded FACIT-Fatigue scores were similar in those with incident (37 units, IQR 25-45.5) and prevalent SSc (36 units, IQR 23-44; p=0.17), as were lowest-ever recorded FACIT-Fatigue scores (incident 23 units; prevalent 22 units, p=0.75). In incident SSc, higher skin scores (regression coefficient (RC) -1.5 units, 95%CI -2.3 to -0.8), PAH (RC -8.2, 95%CI -16.5 to 0.1) and reduced left ventricular function (RC -10.6, 95%CI -18.3 to -2.8) were associated with more severe fatigue. In prevalent SSc, higher skin scores (RC -0.6, 95%CI -1.3 to 0), gastrointestinal symptoms (RC -6.6, 95%CI -9.0 to -4.2), hypoalbuminaemia (RC -2.8, 95%CI -5.0 to -0.7), BMI<18.5kg/m2 (RC -6.3, 95%CI -10.3 to -2.2), raised CRP (RC -3.1, 95%CI -4.7 to -1.5), and anaemia (RC -1.7, 95%CI -3.5 to 0.1) were associated with more severe fatigue. CONCLUSIONS: The burden of fatigue is substantial in both incident and prevalent SSc. Cardiopulmonary and gastrointestinal involvement are associated with worse fatigue.

Tocilizumab use in giant cell arteritis: comparing Pharmaceutical Benefits Scheme eligible and ineligible cases in South Australia.

Tocilizumab (TCZ) is increasingly used as a steroid-sparing agent in giant cell arteritis (GCA), but there are strict Pharmaceutical Benefits Scheme (PBS) restrictions for its use in Australia. Patients who do not meet the PBS criteria can obtain TCZ through public hospital individual patient use (IPU) schemes which may not be universally accessible. We compared patients receiving IPU-approved TCZ with patients receiving PBS-subsidised TCZ and found IPU approvals were granted mainly for visual loss, a serious complication of GCA, in patients who otherwise failed to meet PBS criteria. Further studies demonstrating that TCZ is comparatively more effective than prednisolone monotherapy, as well as cost-effective, are needed to substantiate the rationale for expanding PBS approval criteria.

Predictive accuracy of the ASIG algorithm in a prospective systemic sclerosis cohort undergoing annual screening for pulmonary arterial hypertension.

The Australian Scleroderma Interest Group (ASIG) algorithm for screening pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) requires only respiratory function tests and serum N-terminal pro-brain natriuretic peptide as first-tier tests, and is recommended in international guidelines. In this communication, we present the findings of the application of the ASIG screening algorithm to a Singaporean cohort undergoing prospective annual screening for PAH, which shows a high negative predictive value. The ASIG algorithm may offer an alternative to more complex and costly SSc-PAH screening algorithms.

Female reproductive status and exogenous sex hormone use in rheumatoid arthritis patients treated with tocilizumab and csDMARDs.

OBJECTIVES: Sex is well known to influence risk, severity and treatment outcomes of RA, although the underlying causes are uncertain. The aim of this research was to examine whether factors influencing female sex hormones (reproductive status and exogenous sex hormone use) are associated with the efficacy of DMARDs. METHODS: Individual participant data were pooled from five phase 3 clinical trials where RA patients were treated with tocilizumab and/or conventional synthetic DMARDs. The primary outcome was the time to first remission according to the Simplified Disease Activity Index. The relationship between menopausal status or use of exogenous sex hormones and the time of first remission was assessed via Cox proportional analysis. Analysed data included sex, baseline menopausal status (premenopausal, perimenopausal, early postmenopausal and postmenopausal), participant age, body mass index, race, number of previous DMARDs and baseline disease activity. RESULTS: Analysis included 4474 female patients, of whom 2817 (62.9%) were postmenopausal, 202 (4.5%) were early postmenopausal, 1021 (22.8%) were premenopausal and 414 (9.2%) were perimenopausal. Of these, 221 (7.8%), 13 (6.4%), 255 (25%) and 47 (11.4%), respectively, were taking exogenous sex hormones. In the pooled analysis, perimenopausal status was associated with reduced remission compared with premenopausal status [adjusted HR 0.78 (95% CI 0.61, 0.99)]. Sex hormone use was associated with significantly higher remission [adjusted HR 1.20 (95% CI 1.01, 1.43)]. CONCLUSION: Perimenopausal women were less likely to achieve remission compared with premenopausal RA patients. The use of exogenous sex hormones appeared to be associated with more frequent remission in female RA patients, particularly those who were perimenopausal and early postmenopausal, although further research is required to confirm and identify the drivers for this observation and how it interacts with menopausal status.

Mortality estimates and excess mortality in rheumatoid arthritis.

OBJECTIVES: To determine long-term (20 year) survival in RA patients enrolled in the Australian Rheumatology Association Database (ARAD). METHODS: ARAD patients with RA and data linkage consent who were diagnosed from 1995 onwards were included. Death data were obtained through linkage to the Australian National Death Index. Results were compared with age-, gender- and calendar year-matched Australian population mortality rates. Analysis included both the standardized mortality ratio (SMR) and relative survival models. Restricted mean survival time (RMST) at 20 years was calculated as a measure of life lost. Cause-specific SMRs (CS-SMRs) were estimated for International Classification of Diseases, Tenth Revision cause of death classifications. RESULTS: A total of 1895 RA patients were included; 74% were female, baseline median age 50 years (interquartile range 41-58), with 204 deaths. There was no increase in mortality over the first 10 years of follow up, but at 20 years the SMR was 1.49 (95% CI 1.30, 1.71) and the relative survival was 94% (95% CI 91, 97). The difference between observed (18.41 years) and expected (18.68 years) RMST was 4 months. Respiratory conditions were an important underlying cause of death in RA, primarily attributable to pneumonia [CS-SMR 5.2 (95% CI 2.3, 10.3)] and interstitial lung disease [CS-SMR 7.6 (95% CI 3.0, 14.7)], however, coronary heart disease [CS-SMR 0.82 (95% CI 0.42, 1.4)] and neoplasms [CS-SMR 1.2 (95% CI 0.89, 1.5)] were not. CONCLUSION: Mortality risk in this RA cohort accrues over time and is moderately increased at 20 years of follow-up. Respiratory diseases may have supplanted cardiovascular diseases as a major contributor to this mortality gap.

Progressive pulmonary fibrosis and its impact on survival in systemic sclerosis related interstitial lung disease.

OBJECTIVE: To describe the frequency of progressive pulmonary fibrosis (PPF) in an incident cohort of systemic sclerosis (SSc) related interstitial lung disease (ILD) and its impact on survival. METHODS: Incident ILD was defined as the new development of characteristic fibrotic changes on chest HRCT scan. PPF was defined as per the 2022 American Thoracic Society. Determinants of PPF were identified using generalised estimating equations. Impact on survival was analysed using accelerated failure time regression modelling. RESULTS: Of our incident SSc-ILD cases, 38.8% (n = 180) experienced PPF within a 12-month period after ILD diagnosis. Determinants of PPF included older age (OR 1.02, 95%CI 1.00-1.03, p= 0.011), dcSSc (OR 1.54, 95% CI 1.06-2.25, p= 0.024) and SSc specific antibodies (anticentomere antibody OR 0.51, 95%CI 0.29-0.91, p= 0.021 and anti-Scl-70 antibody OR 1.46, 95%CI 1.01-2.09, p= 0.043). Raised CRP was numerically associated with PPF but did not reach statistical significance (OR 1.29, 95%CI 0.99-1.68, p= 0.064) nor did GORD or dysphagia (OR 1.18, 95%CI 0.57-2.42, p= 0.658 and OR 1.17, 95%CI 0.57-2.40, p= 0.664 respectively). The presence of PPF significantly impacted survival in SSc-ILD (hazard ratio 2.66, 95%CI 1.59-4.41, p< 0.001). CONCLUSIONS: PPF occurred in a third of our incident SSc-ILD cohort; however, its occurrence was significantly associated with mortality indicating an at-risk group who may be suitable for earlier introduction of immunosuppressive and/or antifibrotic therapy.

Prediction of damage trajectories in systemic sclerosis using group-based trajectory modelling.

OBJECTIVES: Damage accrual in SSc can be tracked using the Scleroderma Clinical Trials Consortium Damage Index (DI). Our goal was to develop a prediction model for damage accrual in SSc patients with early disease. METHODS: Using patients with <2 years disease duration from Canada and Australia as a derivation cohort, and from the Netherlands as a validation cohort, we used group-based trajectory modelling (GBTM) to determine 'good' and 'bad' latent damage trajectories. We developed a prediction model from this analysis and applied it to patients from derivation and validation cohorts. We plotted the actual DI trajectories of the patients predicted to be in 'good' or 'bad' groups. RESULTS: We found that the actual trajectories of damage accumulation for lcSSc and dcSSc were very different, so we studied each subset separately. GBTM found two distinct trajectories in lcSSc and three in dcSSc. We collapsed the two worse trajectories in the dcSSc into one group and developed a prediction model for inclusion in either 'good' or 'bad' trajectories. The performance of models using only baseline DI and sex was excellent with ROC AUC of 0.9313 for lcSSc and 0.9027 for dcSSc. Using this model, we determined whether patients would fall into 'good' or 'bad' trajectory groups and then plotted their actual trajectories which showed clear differences between the predicted 'good' and 'bad' cases in both derivation and validation cohorts. CONCLUSIONS: A simple model using only cutaneous subset, baseline DI and sex can predict damage accumulation in early SSc.

The emerging association between bronchiectasis and systemic sclerosis: assessing prevalence and potential causality.

BACKGROUND: Bronchiectasis has been observed in association with systemic sclerosis (SSc). Theorised aetiology includes aspiration related to oesophageal dysmotility, immunosuppressant medication use and the direct effect of collagen deposition on airway calibre. AIMS: To detail bronchiectasis prevalence in an SSc population who have had a high-resolution computed tomography (HRCT) of the thorax. We assessed whether oesophageal dysmotility, demographic variables, SSc duration or subclass were associated with bronchiectasis. METHODS: Participants in the Australian Scleroderma Cohort Study (ASCS) with a HRCT were included. The ASCS provided demographic and clinical data. HRCT studies were reviewed for bronchiectasis, oesophageal dilatation and interstitial lung disease (ILD). Traction bronchiectasis associated with ILD was recorded as a separate entity to bronchiectasis. Oesophageal dysmotility was defined by symptoms and/or oesophageal dilatation. RESULTS: Of the 256 participants, 16.4% (n = 42) had bronchiectasis. Logistic regression analysis revealed no significant association between bronchiectasis and oesophageal dysmotility (observed in 95.7%), any demographic variable, SSc duration or subclass. A negative association between bronchiectasis and ILD was observed (P = 0.009; odds ratio 0.322; 95% confidence intervals 0.137-0.756). CONCLUSION: Those with SSc appear to have an increased risk for bronchiectasis. Since bronchiectasis was not more frequent in participants with a longer duration of SSc, we hypothesise that its development is not related to immunosuppression alone. Oesophageal dysmotility was almost universal in our population such that its effect on bronchiectasis development could not be concluded. A negative association between bronchiectasis and ILD reflects that bronchiectasis occurring alongside ILD was recorded as a separate entity.

Autoantibodies against four-and-a-half-LIM domain 1 (FHL1) in inflammatory myopathies: results from an Australian single-centre cohort.

OBJECTIVES: To determine the prevalence and associations of autoantibodies targeting a muscle-specific autoantigen, four-and-a-half-LIM-domain 1 (FHL1), in South Australian patients with histologically-confirmed idiopathic inflammatory myopathies (IIM) and in patients with SSc. MATERIAL AND METHODS: Sera from patients with IIM (n = 267) from the South Australian Myositis Database (SAMD), SSc (n = 174) from the Australian Scleroderma Cohort Study (ASCS) and healthy controls (HC, n = 100) were analysed for anti-FHL1 autoantibodies by Enzyme-Linked ImmunoSorbent Assay (ELISA). RESULTS: Autoantibodies to FHL1 were more frequent in patients with IIM (37/267, 13.8%) compared with SSc (12/174, 7%) (P < 0.02) and HC (2/100, 2%) (P < 0.001). The most common IIM subtypes among FHL1+ IIM patients were (32%) and IBM (2/37, 32%). No statistically significant differences in muscular or extra-muscular manifestations of IIM were found when comparing patients who were anti-FHL1+ with their anti-FHL1- counterparts. In 29/37 (78%) anti-FHL1+ patients, no myositis-specific autoantibodies (MSA) were present. In FHL1+ muscle biopsies, there was less frequent infiltration by CD45+ cells (P = 0.04). There was a trend for HLA alleles DRB1*07 and DRB1*15 to be more frequent in anti-FHL1+ compared with anti-FHL1- patients (9/25 vs 19/113, P = 0.09 and 8/25 vs 15/114, P = 0.09, respectively). CONCLUSIONS: We report a substantial prevalence (13.8%) of anti-FHL1 autoantibodies in a large cohort of patients with histologically confirmed IIM; 75% of these cases did not have a detectable myositis-specific autoantibody. Anti-FHL1 autoantibodies were also detected in a subgroup of patients with SSc (7%), indicating that anti-FHL1 autoantibodies may not be myositis-specific. The trend towards an HLA-DR association might indicate a specific immune response to the FHL1 protein.

Quantitation of methotrexate polyglutamates in human whole blood, erythrocytes and leukocytes collected via venepuncture and volumetric absorptive micro-sampling: a green LC-MS/MS-based method.

Low-dose methotrexate (MTX) plays a key role in treatment of rheumatoid arthritis. However, not all patients respond satisfactorily, and no therapeutic drug monitoring has been implemented in clinical practice, despite the fact that MTX therapy has now been available for decades. Analysis of individual intracellular MTX metabolites among rheumatoid arthritis (RA) patients is hampered by the low intracellular concentrations of MTX-PGs which require a highly sensitive method to quantify. Here, we present a rapid and highly sensitive LC (HILIC) MS/MS method with LLOQ 0.1 nM, 0.8 nmol/L for each metabolite of MTX-PG1-5 and MTX-PG6-7 respectively. Over a linear range of 0.1-100 nM, 0.8-100 nmol/L for each metabolite of MTX-PG1-5 and MTX-PG6-7, respectively, the inter- and intra- accuracy and precision were within 15% of the nominal value for all MTX metabolites. The presented assay was used to assess and compare MTX metabolite concentrations extracted from four different matrices: red blood cells, plasma, peripheral blood mononuclear cells, and whole blood that have been collected either using traditional venepuncture or volumetric absorptive micro-sampling (VAMS) sampling techniques. The presented method not only improves analyte coverage and sensitivity as compared to other published methods; it also improves the greenness.

Comprehensive analysis of the major histocompatibility complex in systemic sclerosis identifies differential HLA associations by clinical and serological subtypes.

OBJECTIVE: The greatest genetic effect reported for systemic sclerosis (SSc) lies in the major histocompatibility complex (MHC) locus. Leveraging the largest SSc genome-wide association study, we aimed to fine-map this region to identify novel human leucocyte antigen (HLA) genetic variants associated with SSc susceptibility and its main clinical and serological subtypes. METHODS: 9095 patients with SSc and 17 584 controls genome-wide genotyped were used to impute and test single-nucleotide polymorphisms (SNPs) across the MHC, classical HLA alleles and their composite amino acid residues. Additionally, patients were stratified according to their clinical and serological status, namely, limited cutaneous systemic sclerosis (lcSSc), diffuse cutaneous systemic sclerosis (dcSSc), anticentromere (ACA), antitopoisomerase (ATA) and anti-RNApolIII autoantibodies (ARA). RESULTS: Sequential conditional analyses showed nine SNPs, nine classical alleles and seven amino acids that modelled the observed associations with SSc. This confirmed previously reported associations with HLA-DRB1*11:04 and HLA-DPB1*13:01, and revealed a novel association of HLA-B*08:01. Stratified analyses showed specific associations of HLA-DQA1*02:01 with lcSSc, and an exclusive association of HLA-DQA1*05:01 with dcSSc. Similarly, private associations were detected in HLA-DRB1*08:01 and confirmed the previously reported association of HLA-DRB1*07:01 with ACA-positive patients, as opposed to the HLA-DPA1*02:01 and HLA-DQB1*03:01 alleles associated with ATA presentation. CONCLUSIONS: This study confirms the contribution of HLA class II and reveals a novel association of HLA class I with SSc, suggesting novel pathways of disease pathogenesis. Furthermore, we describe specific HLA associations with SSc clinical and serological subtypes that could serve as biomarkers of disease severity and progression.

Right ventricular myocardial deoxygenation in patients with pulmonary artery hypertension.

BACKGROUND: In pulmonary arterial hypertension (PAH), progressive right ventricular (RV) dysfunction is believed to be largely secondary to RV ischaemia. A recent pilot study has demonstrated the feasibility of Oxygen-sensitive (OS) cardiovascular magnetic resonance (CMR) to detect in-vivo RV myocardial oxygenation. The aims of the present study therefore, were to assess the prevalence of RV myocardial ischaemia and relationship with RV myocardial interstitial changes in PAH patients with non-obstructive coronaries, and corelate with functional and haemodynamic parameters. METHODS: We prospectively recruited 42 patients with right heart catheter (RHC) proven PAH and 11 healthy age matched controls. The CMR examination involved standard functional imaging, OS-CMR imaging and native T1 mapping. An ΔOS-CMR signal intensity (SI) index (stress/rest signal intensity) was acquired at RV anterior, RV free-wall and RV inferior segments. T1 maps were acquired using Shortened Modified Look-Locker Inversion recovery (ShMOLLI) at the inferior RV segment. RESULTS: The inferior RV ΔOS-CMR SI index was significantly lower in PAH patients compared with healthy controls (9.5 (- 7.4-42.8) vs 12.5 (9-24.6)%, p = 0.02). The inferior RV ΔOS-CMR SI had a significant correlation to RV inferior wall thickness (r = - 0.7, p < 0.001) and RHC mean pulmonary artery pressure (mPAP) (r = - 0.4, p = 0.02). Compared to healthy controls, patients with PAH had higher native T1 in the inferior RV wall: 1303 (1107-1612) vs 1232 (1159-1288)ms, p = 0.049. In addition, there was a significant difference in the inferior RV T1 values between the idiopathic PAH and systemic sclerosis associated PAH patients: 1242 (1107-1612) vs 1386 (1219-1552)ms, p = 0.007. CONCLUSION: Blunted OS-CMR SI suggests the presence of in-vivo microvascular RV dysfunction in PAH patients. The native T1 in the inferior RV segments is significantly increased in the PAH patients, particularly among the systemic sclerosis associated PAH group.

Immunosuppression does not prevent severe gastrointestinal tract involvement in systemic sclerosis.

OBJECTIVES: We aimed to test the hypothesis that exposure to immunosuppression in early systemic sclerosis (SSc) could modify the risk of developing new onset severe gastrointestinal (GIT) involvement. METHODS: A total of 762 subjects with <3 years of disease duration and without severe GIT disease at baseline study visit were identified from combined longitudinal cohort data from the Canadian Scleroderma Research Group (CSRG) and Australian Scleroderma Interest Group (ASIG). The primary exposure was ever use of methotrexate, cyclophosphamide, mycophenolate mofetil and/or azathioprine during the study period. Severe GIT disease was defined as: 1-malabsorption, 2-hyperalimentation, 3-pseudo-obstruction, and/or 4-≥10% weight loss in association with the use of antibiotics for bacterial overgrowth or oesophageal stricture. The change in the hazard of severe GIT disease due to exposure was estimated using a marginal structural Cox proportional hazards model fit by inverse probability of treatment weights (IPTW) to address potential confounding. RESULTS: Study subjects were 81.5% female, had a mean age of 53.7±13.0 years and mean disease duration at baseline of 1.4±0.8 years. During a mean follow-up of 4.0±2.6 years, severe GIT involvement developed in 11.6% of the 319 subjects exposed to immunosuppression and in 6.8% of the 443 unexposed subjects. In an IPTW-adjusted analysis, exposure to immunosuppression was not associated with severe GIT disease (weighted hazard ratio 0.91, 95% confidence interval 0.52-1.58). CONCLUSIONS: In this large inception SSc cohort, the risk of severe GIT involvement was not modified by exposure to immunosuppression.

Patient satisfaction and acceptability with telehealth at specialist medical outpatient clinics during the COVID-19 pandemic in Australia.

BACKGROUND: Outpatient clinics were shifted rapidly to telehealth in Australia during the Coronavirus disease 19 (COVID-19) pandemic, drastically altering patient care and experience. AIMS: To investigate patient satisfaction and acceptability of telehealth consultations during the COVID-19 pandemic. METHODS: Prospective observation study conducted in two hospital rheumatology outpatient departments (OPD) undertaking telehealth consultations during COVID-19. A modified version of a validated telehealth evaluation survey was posted to all patients attending the telehealth OPD rheumatology clinics, including balanced 5-point Likert scales and free-text responses. Cluster analysis was applied to the Likert-scale questions, alongside thematic analysis of free-text responses. RESULTS: There were 128 respondents (29% response rate), of which 69.5% were women and the majority (87.5%) was aged 50 years or older. All telehealth consultations were conducted by telephone. Nearly one-fifth of patients indicated consistent dissatisfaction with telehealth across the range of questions. These patients were older, reported lower educational qualifications and lower health literacy scores and lacked access to the Internet. While many patients found this mode of consultation to be convenient, patients expressed concerns regarding absence of physical examination. A recurrent theme was a desire for a mixed-model clinic in the future, with flexibility of having both telehealth and face-to-face consultations. CONCLUSIONS: This study offers unique insights into patients' experiences with telehealth, which until the current global pandemic, has been an uncommon mode of consultation delivery in urban areas. This study suggests when defining the place of telehealth in future healthcare delivery, patient perspective and careful patient selection will be key. Disease progression, language and cognitive ability, health literacy, technology access and patient and clinician preference are important considerations when deciding how effectively to embed and integrate telehealth into consultations.