Rituximab treatment for systemic sclerosis-associated interstitial lung disease: a case series of 13 patients.

BACKGROUND: Systemic sclerosis (SSc) associated interstitial lung disease (ILD) is a common complication of SSc, with a high mortality, despite current available treatments. Rituximab has shown some promising, although varied, results for the treatment of SSc-ILD. AIMS: To determine whether rituximab stabilised or improved pulmonary function at 12 months, in patients with SSc-ILD. METHODS: A retrospective analysis of patients with SSc-ILD who progressed despite conventional therapy and received rituximab between 2008 and 2019 was performed at two tertiary centres. Baseline percentage forced vital capacity (FVC) and percentage diffusing capacity of carbon monoxide (DLCO) were compared with 1-year post the first dose of rituximab. Mean and median change in FVC (%) and DLCO (%) were calculated. For those with available data, the FVC (%) and DLCO (%) 2 years and 1 year prior to rituximab were compared with the change 12-months post-rituximab. RESULTS: Thirteen patients were included in the analysis. All patients demonstrated stability in their pulmonary function testing at 1-year post-rituximab. The mean FVC (%) was 57.18 (±16.93 standard deviation (SD)) prior to rituximab and 59.75 (±18.83 SD) 12-month post-rituximab, demonstrating an increase of 2.57 (±4.70 SD; P-value 0.07). The mean DLCO (%) increased from 37.10 (±18.41 SD) prior to rituximab to 38.03 (±19.83) post-rituximab. The mean change in DLCO (%) was 0.93 (±5.05 SD; P-value 0.53). In the 2 years preceding rituximab, the mean FVC (%) and DLCO (%) declined by 9.25 and 9.66 respectively. CONCLUSION: This case series suggests that rituximab might stabilise pulmonary function tests, and delay deterioration in patients with progressive SSc-ILD. These findings add to the growing body of evidence suggesting a role for rituximab in the treatment of SSc-ILD.

Contribution of HLA and KIR Alleles to Systemic Sclerosis Susceptibility and Immunological and Clinical Disease Subtypes.

Systemic sclerosis (SSc) is an autoinflammatory, fibrotic condition of unknown aetiology. The presence of detectable autoantibodies against diverse nuclear antigens, as well as strong HLA associations with disease, suggest autoimmune involvement, however the links between endogenous and exogenous risk factors and SSc pathology remain undetermined. We have conducted a genetic analysis of HLA inheritance in two independent and meta-analysed cohorts of 1,465 SSc cases and 13,273 controls, including stratified association analyses in clinical and autoantibody positive subgroups of disease. Additionally, we have used patient genotypes to impute gene dosages across the KIR locus, encoding paired activating and inhibitory lymphocyte receptors for Class I HLA ligands, to conduct the largest analysis of KIR-HLA epistatic interactions in SSc to date. We confirm previous Class II HLA associations with SSc risk and report a new Class I association with haplotype HLA-B*44:03-HLA-C*16:01 at genome-wide significance (GWS). We further report statistically significant HLA associations with clinical and serological subtypes of disease through direct case-case comparison, and report a new association of HLA-DRB1*15:01, previously shown to bind topoisomerase-1 derived peptides, with anti-topoisomerase (ATA) positive disease. Finally, we identify genetic epistasis between KIRs and HLA class I ligands, suggesting genetic modulation of lymphocyte activation may further contribute to an individual's underlying disease risk. Taken together, these findings support future functional investigation into endogenous immunological and environmental stimuli for disrupted immune tolerance in SSc.

Gastric antral vascular ectasia in systemic sclerosis: a study of its epidemiology, disease characteristics and impact on survival.

BACKGROUND: To describe the epidemiology, determinants and survival impact of gastric antral vascular ectasia (GAVE) in systemic sclerosis (SSc). METHODS: Consecutive SSc patients prospectively enrolled in the Australian Scleroderma Cohort Study (ASCS) were included. Univariable and multivariable logistic regression were used to determine the associations of GAVE with clinical manifestations and serological parameters. Kaplan-Meier (K-M) survival curves were used to estimate survival. RESULTS: The prevalence of GAVE in this SSc cohort of 2039 SSc patients was 10.6% (n = 216) over a median follow-up period of 4.3(1.7-8.4) years. SSc patients with a history of GAVE compared with those without a history of GAVE were older at SSc onset [49.5 (40.0-58.2) vs 46.7 (36.0-56.7) years, p = 0.05]; more likely to have diffuse disease subtype (dcSSc) (35.3% vs 24.1%, p < 0.001); be negative for Scl-70, U1RNP and Scl/PM antibody (4.0% vs 16.1%, p < 0.001, 3.5% vs 7.4%, p = 0.041, 0.0% vs 2.0%, p = 0.042; and respectively) and positive for RNAP III antibody (24.9% vs 8.3%, p < 0.001). Those with GAVE had a worse HRQoL (p = 0.002). Independent determinants of GAVE included the presence of RNAP III antibody (OR 3.46, p < 0.001), absence of Scl-70 antibody (OR 0.23, p = 0.001), presence of GIT dysmotility (OR 1.64, p = 0.004), and digital ulcers; pits; or digital amputation (OR 1.59, p = 0.014). CONCLUSIONS: GAVE is an underestimated and underappreciated SSc manifestation of SSc, which occurs with a relatively high frequency. Identifying an at-risk GAVE phenotype, as presented herein, is of practical importance as screening may prove advantageous given GAVE can be easily diagnosed and treated.

47XXY and 47XXX in Scleroderma and Myositis.

OBJECTIVE: We undertook this study to examine the X chromosome complement in participants with systemic sclerosis (SSc) as well as idiopathic inflammatory myopathies. METHODS: The participants met classification criteria for the diseases. All participants underwent single-nucleotide polymorphism typing. We examined X and Y single-nucleotide polymorphism heterogeneity to determine the number of X chromosomes. For statistical comparisons, we used χ2 analyses with calculation of 95% confidence intervals. RESULTS: Three of seventy men with SSc had 47,XXY (P = 0.0001 compared with control men). Among the 435 women with SSc, none had 47,XXX. Among 709 men with polymyositis or dermatomyositis (PM/DM), seven had 47,XXY (P = 0.0016), whereas among the 1783 women with PM/DM, two had 47,XXX. Of 147 men with inclusion body myositis (IBM), six had 47,XXY, and 1 of the 114 women with IBM had 47,XXX. For each of these myositis disease groups, the excess 47,XXY and/or 47,XXX was significantly higher compared with in controls as well as the known birth rate of Klinefelter syndrome or 47,XXX. CONCLUSION: Klinefelter syndrome (47,XXY) is associated with SSc and idiopathic inflammatory myopathies, similar to other autoimmune diseases with type 1 interferon pathogenesis, namely, systemic lupus erythematosus and Sjögren syndrome.

Long-term Clinical Outcomes in Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis Syndrome.

OBJECTIVE: To assess the outcome of empirical therapeutic interventions for synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. METHODS: The clinical features and treatment outcomes of a cohort of 21 patients diagnosed with SAPHO in Western Australia were reviewed retrospectively. RESULTS: All 21 patients met published diagnostic criteria; 20 (95%) were Caucasian, and the median age was 47 years. The median follow-up was 6 years (range, 2 to 32 years). Three patients (14%) received no treatment; 18 (86%) required conventional synthetic disease-modifying antirheumatic drug (DMARDs). Thirteen (62%) had an initial good response to methotrexate; 8 relapsed and progressed to biologic DMARDs (bDMARDs) during a period of 14 years. Of the 13 recipients on a tumor necrosis factor inhibitor, 11 (85%) continued treatment for a median of 4 years (range, 1 to 14 years), whereas none of 3 recipients of interleukin 17/23 continued treatment (median, 4 months). Higher Physician Global Assessment scores (better outcomes) were observed in bDMARD recipients (mean, 7.06±2.24 [SD]) compared with non-bDMARD recipients (mean, 5.63±2.50; P=.1672) after a median of 3 years of therapy. CONCLUSION: This study describes the broad range of clinical manifestations in SAPHO, variable courses over time, and inconsistent outcomes with diverse empirical therapies. Moderately good long-term treatment outcomes were observed in most recipients of tumor necrosis factor inhibitor. Poorer outcomes were observed with bisphosphonates and interleukin 17/23 axis inhibitors; however, low numbers preclude robust comparison. Suboptimal treatment may be associated with poorer clinical outcomes and greater skeletal damage. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry: ACTRN12619000445178.

Clinical Features of Systemic Sclerosis-Mixed Connective Tissue Disease and Systemic Sclerosis Overlap Syndromes.

OBJECTIVE: To describe the clinical characteristics and outcomes of systemic sclerosis-mixed connective tissue disease (SSc-MCTD) and SSc overlap syndrome. METHODS: We included patients from the Australian Scleroderma Cohort Study who met American College of Rheumatology/European Alliance of Associations for Rheumatology criteria for SSc. Three mutually exclusive groups were created: SSc-MCTD, SSc overlap, and SSc only. Univariate comparison of clinical features was performed by analysis of variance or chi-square test. Survival analysis was performed using Kaplan-Meier (KM) curves and Cox proportional hazards regression models. RESULTS: Of 1,728 patients, 97 (5.6%) had SSc-MCTD, and 126 (7.3%) had SSc overlap. Those with MCTD-SSc were more commonly Asian (18.3% versus 10.1% in SSc overlap, and 3.6% in SSc only; P < 0.0001) and younger at disease onset (38.4 years versus 46.5 or 46.8 years, P < 0.0001). Those with SSc-MCTD or SSc overlap were more likely to have limited cutaneous SSc. All 3 groups had similar frequency of interstitial lung disease (ILD), although pulmonary arterial hypertension (PAH) was less common in SSc overlap. Synovitis and myositis were more common in SSc overlap and SSc-MCTD than in SSc only. KM curves showed better survival in SSc-MCTD than SSc overlap or SSc only (P = 0.011), but this was not significant after adjustment for sex and age at disease onset. SSc-specific antibodies were survival prognostic markers, with antinuclear antibody centromere or anti-RNP conferring better survival than anti-Scl-70 or anti-RNA polymerase III (P = 0.005). Patients with SSc-MCTD and SSc overlap had lower mortality following diagnosis of ILD and PAH than patients with SSc only. CONCLUSION: This study provides insights into the clinical characteristics of patients with SSc-MCTD, SSc overlap, and SSc only and shows that anti-RNP antibodies are associated with better survival than anti-Scl-70 and anti-RNA polymerase III antibodies.

Occupational silica exposure in an Australian systemic sclerosis cohort.

OBJECTIVE: To determine the frequency of self-reported occupational exposure to silica in SSc patients enrolled in the Australian Scleroderma Cohort Study, and to compare the disease characteristics of the silica-exposed patients with those of the non-exposed patients. METHOD: Data collected over a 12-year period from 1670 SSc patients were analysed. We compared the demographic and clinical characteristics of those who reported occupational silica exposure with those who did not. A subgroup analysis of male patients was performed, as well as a multivariable analysis of correlates of silica exposure. RESULTS: Overall, 126 (7.5%) of the cohort reported occupational silica exposure. These individuals were more likely to be male (73 of 231, i.e. 31.6% males exposed) and to have worked in mining and construction industries. Those who reported silica exposure were younger at the onset of SSc skin involvement [odds ratio (OR) 0.9, P = 0.02], of male gender (OR 14.9, P < 0.001), have joint contractures (OR 1.8, P = 0.05) and have higher physical disability as defined by scleroderma HAQ (OR 1.4, P = 0.01). CONCLUSION: The highest percentage of silica exposure was found in males. These patients were more likely to have the presence of certain clinical manifestations and Scl-70 antibody, which is known to confer a poor prognosis. These findings support the association between occupational silica exposure and the subsequent development of SSc. Further investigation is required to describe the range of clinical manifestations and disease course, including prognosis and treatment response, in those diagnosed with occupationally induced SSc compared with idiopathic SSc.

Performance of the 2017 EUSTAR activity index in an scleroderma cohort.

Assessment of disease activity in systemic sclerosis (SSc) is limited by the absence of a fully validated, multisystem measure of disease activity. The European Scleroderma Trials and Research Group (EUSTAR) SSc activity index (EScSG-AI) was recently revised, and a validation study within the EUSTAR cohort was performed. In this study, we evaluated the performance of the revised EScSG-AI in an external Australian cohort. The association between the EScSG-AI and the physician global assessment of disease activity (PhGA), both collected prospectively at each annual visit over up to 12 years follow-up, was evaluated using Pearson's correlation coefficient and Cohen's kappa coefficient. Generalized linear modelling and time-dependent Cox regression analysis were performed to determine the association of disease activity measured by the EScSG-AI and the summed Medsger Severity Scale (MSS) and death, respectively. There was a moderate correlation between EScSG-AI and PhGA scores (r 0.42, p < 0.001) and moderate association between rising EScSG-AI and summed MSS (r 0.60, p < 0.001). High disease activity, measured by the EScSG-AI at any time during follow-up, was associated with a hazard ratio of 2.07 (95% CI 1.51-2.79) for mortality. The EScSG-AI has a moderate correlation with physician-assessed SSc disease activity. This suggests that the criterion and construct validity of the EScSG-AI are yet to be demonstrated in an external cohort of SSc patients. Key Points •There remains no gold standard measure of SSc disease activity. •The revised 2017 EUSTAR SSc disease activity index shows moderate correlation with physician-rated global disease activity. •Significant work remains to develop a validated multisystem measure of disease activity in SSc.

Incidence, Risk Factors, and Outcomes of Cancer in Systemic Sclerosis.

OBJECTIVE: To quantify the burden of cancer in systemic sclerosis (SSc). METHODS: Standardized incidence ratios (SIRs) and standardized mortality ratios relative to the general Australian population were derived. Cox proportional hazards regression was used to estimate survival in patients with SSc with cancer compared to patients without. Determinants of cancer were identified using logistic regression. Health care cost was quantified through cross-jurisdictional data linkage. RESULTS: This SSc cohort of 1,727 had a cancer incidence of 1.3% per year and a prevalence of 14.2%, with a SIR of 2.15 (95% confidence interval [95% CI] 1.84-2.49). The most common cancers were breast, melanoma, hematologic, and lung. Anti-RNA polymerase III (RNAP) antibody was associated with an increased risk of cancer (odds ratio [OR] 2.9, P = 0.044), diagnosed within 5 years of SSc disease onset. Calcium channel blockers were associated with a higher risk of overall cancer (OR 1.47, P = 0.016), breast cancer (OR 1.61, P = 0.051), and melanoma (OR 2.01, P = 0.042). Interstitial lung disease (ILD) was associated with lung cancer (OR 2.83, P = 0.031). Incident SSc cancer patients had >2-fold increased mortality compared to patients with SSc without cancer (hazard ratio 2.85 [95% CI 1.51-5.37], P = 0.001). Patients with SSc and cancer utilized more health care than those without cancer, with an excess annual health care cost of $1,496 Australian (P < 0.001). CONCLUSION: SSc carries an increased risk of developing cancer, particularly lung cancer associated with ILD, and breast cancer and melanoma occurring close to SSc disease onset in association with RNAP antibodies. Compared to those patients without cancer, patients with SSc and cancer had higher mortality and an increased health care cost, with an annual excess per patient cost of $1,496 Australian (P < 0.001).

Can Patient-Reported Symptoms Be Used to Measure Disease Activity in Systemic Sclerosis?

OBJECTIVE: To evaluate the association between patient-reported symptoms and changes in disease activity over time in systemic sclerosis (SSc). METHODS: Using data from 1,636 patients enrolled in the Australian Scleroderma Cohort Study, we used generalized estimating equations to determine the relationship between patient-reported worsening of Raynaud's phenomenon (RP), skin involvement, and breathlessness in the month preceding each study visit and features of disease activity in the corresponding organ systems. The associations between the following parameters were analyzed: patient-reported worsening RP and the presence of new-onset digital pitting and digital ulcers; patient-reported worsening skin involvement and increasing modified Rodnan skin thickness score (MRSS); new areas of skin involvement and new-onset joint contractures; patient-reported worsening breathlessness and deteriorating respiratory functions test (RFT) results, indicated by a 10% decrease in forced vital capacity (FVC) and a 15% decrease in diffusing capacity for carbon monoxide (DLco), new-onset interstitial lung disease (ILD), and new-onset pulmonary arterial hypertension (PAH). RESULTS: We found a significant association between patient-reported worsening RP and the presence of digital ulcers (odds ratio [OR] 1.53 [95% confidence interval (95% CI) 0.60-0.93]), patient-reported worsening skin involvement and increasing MRSS (OR 2.10 [95% CI 1.54-2.86]), and worsening patient breathlessness and deteriorating RFTs (FVC OR 2.12 [95% CI 1.70-2.65]; DLco OR 1.97 [95% CI 1.34-2.02]), new-onset ILD (OR 1.91 [95% CI 1.40-2.61]), and new-onset PAH (OR 5.08 [95% CI 3.59-7.19]). CONCLUSION: These results demonstrate that patient-reported symptoms are associated with clinically meaningful changes in disease activity in patients with SSc. This suggests that when objective measures of change in disease status are unavailable, patient-reported symptoms could be used to indicate a change in SSc disease activity.

The clinical and economic burden of systemic sclerosis related interstitial lung disease.

OBJECTIVE: To quantify the burden of interstitial lung disease (ILD) in SSc. METHODS: Clinical data for SSc patients enrolled in the Australian Scleroderma Cohort Study were linked with healthcare databases for the period 2008-2015. ILD was defined by characteristic fibrotic changes on high-resolution CT (HRCT) lung, while severity was defined by the extent lung involvement on HRCT (mild <10%, moderate 10-30%, severe >30%). Determinants of healthcare cost were estimated using logistic regression. RESULTS: SSc-ILD patients utilized more healthcare resources, including hospitalization, emergency department presentation and ambulatory care services, than those without ILD with a total cost per patient of AUD$48 368 (26 230-93 615) vs AUD$33 657 (15 144-66 905), P<0.001) between 2008-2015. Healthcare utilization was associated with an annual median (25th-75th) excess cost per SSc-ILD patient compared with those without ILD of AUD$1192 (807-1212), P<0.001. Increasing ILD severity was associated with significantly more healthcare utilization and costs with an annual excess cost per patient with severe ILD compared with mild ILD of AUD$2321 (645-1846), P<0.001. ILD severity and the presence of coexistent PAH were the main determinants of overall healthcare cost above median for this SSc-ILD cohort (OR 5.1, P<0.001, and OR 2.6, P=0.01, respectively). Furthermore, SSc-ILD patients reported worse physical HRQoL compared with those without ILD [34.3 (10.5) vs 39.1 (10.8), P<0.001], with a progressive decline with increasing ILD severity (P=0.002). CONCLUSION: SSc-ILD places a large burden on the healthcare system and the patient through poor HRQoL in addition to incremental healthcare resource utilization and associated direct cost.

Digital ulcers in systemic sclerosis: their epidemiology, clinical characteristics, and associated clinical and economic burden.

BACKGROUND: To determine the frequency and clinical characteristics of systemic sclerosis-related digital ulcers, and associated direct health care costs, quality of life, and survival. METHODS: Digital ulcers (DUs) were defined as an area with a visually discernible depth and a loss of continuity of epithelial coverage. DU severity was calculated based on the physician reported highest number of new DUs at clinical review (mild = 1-5 DUs, moderate 6-10 DUs, severe > 10 DUs). Healthcare use was captured through data linkage, wherein SSc clinical data captured prospectively in a dedicated clinical database were linked with health services databases to capture hospital admissions, emergency department (ED) presentations and ambulatory care (MBS) utilization and cost for the period 2008-2015. Healthcare cost determinants were estimated using logistic regression. RESULTS: Among 1085 SSc patients, 48.6% experienced a DU over a mean follow-up of 5.2 ± 2.5 years. Those who developed DUs were more likely to have diffuse disease subtype (34.9% vs 18.2%, p < 0.001), anti-Scl-70 antibody (18.9% vs 9.3%, p < 0.001), and a younger age at SSc onset (43.6 ± 13.9 vs 48.8 ± 14.0 years, p < 0.001) in addition to reduced health-related quality of life (HRQoL) measured by the SF-36 but without a significant impact on survival. SSc patients with a history of a DU utilized significantly more healthcare resources per annum than those without a DU, including hospitalizations, ED presentation, and ambulatory care services. Total healthcare services, excluding medications, were associated with an annual excess cost per DU patient of AUD$12,474 (8574-25,677), p < 0.001, driven by hospital admission and ED presentation costs. CONCLUSION: DUs place a large burden on the patient and healthcare system through reduced HRQoL and increased healthcare resource utilization and associated cost.

The economic burden of systemic sclerosis related pulmonary arterial hypertension in Australia.

BACKGROUND: To quantify the financial cost of pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc). METHODS: Healthcare use was captured through data linkage, wherein clinical data for SSc patients enrolled in the Australian Scleroderma Cohort Study were linked with hospital, emergency department (ED) and ambulatory care databases (MBS) for the period 2008-2015. PAH was diagnosed on right heart catheter according to international criteria. Determinants of healthcare cost were estimated using logistic regression. RESULTS: Total median (25th-75th) healthcare cost per patient (including hospital, ED and MBS cost but excluding medication cost) for our cohort during 2008-2015 was AUD$37,685 (18,144-78,811) with an annual per patient healthcare cost of AUD$7506 (5273-10,654). Total healthcare cost was higher for SSc-PAH patients compared with those without PAH with a total cost per patient of AUD$70,034 (37,222-110,814) vs AUD$34,325 (16,093 - 69,957), p < 0.001 respectively with an annual excess healthcare cost per PAH patient of AUD$2463 (1973-1885), p < 0.001. The cost of SSc-PAH occurs early post PAH diagnosis with 89.4% utilizing a healthcare service within the first 12 months post PAH diagnosis with an associated cost per patient of AUD$4125 (0-15,666). PAH severity was the main significant determinant of increased healthcare cost (OR 2.5, p = 0.03) in our PAH cohort. CONCLUSIONS: Despite SSc-PAH being a low prevalence disease, it is associated with significant healthcare resource utilization and associated economic burden, predominantly driven by the severity of PAH.

IFNL3 genotype is associated with pulmonary fibrosis in patients with systemic sclerosis.

Fibrosis across different organs and tissues is likely to share common pathophysiological mechanisms and pathways. Recently, a polymorphism (rs12979860) near the interferon lambda gene (IFNL3) was shown to be associated with fibrosis in liver across multiple disease etiologies. We determined whether this variant is a risk factor for pulmonary fibrosis (PF) and worsening cutaneous fibrosis in systemic sclerosis (SSc). Caucasian patients with SSc (n = 733) were genotyped to test for association with the presence of PF and worsening of skin fibrosis. Serum IFN-λ3 levels from 200 SSc cases were evaluated. An association of the IFNL3 polymorphism with PF was demonstrated (OR: 1.66 (95% CI: 1.142-2.416, p = 0.008). The IFNL3 variant was not a risk factor for worsening of skin fibrosis. Functionally, IFN-λ3 serum levels were higher among subjects with PF compared to those unaffected (P < 0.0001). In conclusion, IFNL3 serum levels and the genetic variant known to be associated with liver fibrosis are similarly linked to PF, but not to worsening of skin fibrosis in SSc. These data highlight both common fibrosis pathways operating between organs, as well as differential effects within the same disease.

Significance of anti-neutrophil cytoplasmic antibodies in systemic sclerosis.

BACKGROUND: Up to 12% of patients with systemic sclerosis (SSc) have anti-neutrophil cytoplasmic antibodies (ANCA). However, the majority of these patients do not manifest ANCA-associated vasculitis (AAV) and the significance of ANCA in these patients is unclear. The aim of this study is to determine the prevalence of ANCA in a well-characterised SSc cohort and to examine the association between ANCA and SSc clinical characteristics, other autoantibodies, treatments and mortality. METHODS: Clinical data were obtained from 5 centres in the Australian Scleroderma Cohort Study (ASCS). ANCA positive was defined as the presence of any one or combination of cytoplasmic ANCA (c-ANCA), perinuclear ANCA (p-ANCA), atypical ANCA, anti-myeloperoxidase (anti-MPO) or anti-proteinase-3 (anti-PR3). Associations of demographic and clinical features with ANCA were investigated by logistic or linear regression. Survival analysis was performed using Kaplan-Meyer curves and Cox regression models. RESULTS: Of 1303 patients, 116 (8.9%) were ANCA positive. Anti-PR3 was more common than anti-MPO (13.8% and 11.2% of ANCA-positive patients, respectively). Only 3 ANCA-positive patients had AAV. Anti-Scl-70 was more common in ANCA positive vs ANCA negative (25% vs 12.8%, p < 0.001), anti-MPO positive vs anti-MPO negative (38.5% vs 13.6%, p = 0.006) and anti-PR3 positive vs anti-PR3 negative patients (44.4% vs 13.4%, p < 0.001). A higher prevalence of interstitial lung disease (ILD) was found in the ANCA positive (44.8% vs 21.8%, p < 0.001) and the anti-PR3 positive groups (50.0% vs 23.4%, p = 0.009). In multivariable analysis, ANCA-positive status remained associated with ILD after adjusting for anti-Scl-70 antibodies. Pulmonary embolism (PE) was more common in ANCA-positive patients (8.6% vs 3.0%, p = 0.002) and anti-PR3-positive patients (16.7% vs 3.3%, p = 0.022). ANCA-positive status remained associated with PE in a multivariable analysis adjusting for anti-phospholipid antibodies. Kaplan-Meier analysis revealed increased mortality in ANCA-positive patients (p = 0.006). In Cox regression analysis, ANCA was associated with increased mortality, after adjusting for age and sex. CONCLUSIONS: ANCA is associated with increased prevalence of ILD and PE in SSc. ANCA should be tested in SSc, as it identifies individuals with worse prognosis who require close monitoring for adverse outcomes.

The role of inflammatory markers in assessment of disease activity in systemic sclerosis.

OBJECTIVES: The role of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in the assessment of disease activity in systemic sclerosis (SSc) remains controversial. We sought to evaluate the relationship between clinical features of SSc and raised inflammatory markers and to determine if changes in ESR and CRP reflect changes in other disease features over time. METHODS: One thousand, five hundred and forty-five patients enrolled in the Australian Scleroderma Cohort Study were observed over a mean 3.52±2.91 years and assessed at 6,119 study visits. Generalised estimating equations were used to determine the relationship between ESR≥20mm/hr and CRP≥5mg/L and features of disease. The associations between change in inflammatory markers and change in skin scores and respiratory function tests were analysed. RESULTS: Overall, there was a significant association between raised ESR and forced vital capacity (FVC)<80% predicted, diffusing capacity of the lung (DLCO)<80% predicted, pulmonary arterial hypertension (PAH), body mass index (BMI), proximal muscle strength, anaemia, and hypocomplementaemia (p<0.05). Raised CRP was significantly associated with modified Rodnan Skin Score>20, FVC<80%, DLCO<80%, PAH, digital ulcers, BMI, synovitis, tendon friction rub, anaemia, and hypocomplementaemia (p<0.05). A significant deterioration in respiratory function tests (RFTs) was associated with a 2-fold increase in both ESR and CRP (p<0.05). CONCLUSIONS: Raised inflammatory markers are associated with pulmonary, cutaneous and musculoskeletal manifestations of SSc. Rising inflammatory markers are correlated with declining respiratory function tests. This suggests inflammatory markers have a role in the assessment of SSc disease activity.

Increased serum levels of adhesion molecules ICAM-1 and VCAM-1 in systemic sclerosis are not specific for pulmonary manifestations.

Studies suggest elevated serum intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels may be markers of pulmonary arterial hypertension in systemic sclerosis (SSc-PAH). We sought to evaluate whether ICAM-1 and VCAM-1 levels are useful screening biomarkers for incident SSc-PAH. In this cross-sectional study, four groups were selected from the Australian Scleroderma Cohort Study: group 1 (n = 15) had definite PAH; group 2 (n = 19) had interstitial lung disease (ILD); group 3 (n = 30) were SSc-controls; and group 4 (n = 34) were healthy controls. Serum ICAM-1 and VCAM-1 levels were measured using the Millipore Milliplex MAP Human 2-Plex Panel. There were no differences in ICAM-1 levels in the PAH versus ILD group (263.0 ± 85.4 vs 380.4 ± 168.3 ng/mL, p = 0.136), SSc-controls (263.0 ± 85.4 vs 253.1 ± 98.0 ng/mL, p = 1.00), or healthy controls (263.0 ± 85.4 vs 201.8 ± 57.2 ng/mL, p = 0.093). Similarly, there were no differences in VCAM-1 level in PAH versus ILD groups (1476.2 ± 434.9 vs 1424.8 ± 527.6 ng/mL, p = 1.00) and SSc-controls (1476.2 ± 434.9 vs 1409.5 ± 341.1 ng/mL, p = 1.00). SSc subjects had significantly higher levels of ICAM-1 (297.4 ± 134.0 vs 201.8 ± 57.2 ng/mL, p < 0.0001) and VCAM-1 compared to healthy controls (1432.7 ± 427.4 vs 1125.6 ± 273.4 ng/mL, p < 0.0001). Neither ICAM-1 nor VCAM-1 is a specific screening biomarker of SSc-PAH. Instead, increased levels of these adhesion molecules in SSc, irrespective of pulmonary complications, suggest that they may play a role in SSc pathogenesis.

Patterns and predictors of skin score change in early diffuse systemic sclerosis from the European Scleroderma Observational Study.

OBJECTIVES: Our aim was to use the opportunity provided by the European Scleroderma Observational Study to (1) identify and describe those patients with early diffuse cutaneous systemic sclerosis (dcSSc) with progressive skin thickness, and (2) derive prediction models for progression over 12 months, to inform future randomised controlled trials (RCTs). METHODS: The modified Rodnan skin score (mRSS) was recorded every 3 months in 326 patients. 'Progressors' were defined as those experiencing a 5-unit and 25% increase in mRSS score over 12 months (±3 months). Logistic models were fitted to predict progression and, using receiver operating characteristic (ROC) curves, were compared on the basis of the area under curve (AUC), accuracy and positive predictive value (PPV). RESULTS: 66 patients (22.5%) progressed, 227 (77.5%) did not (33 could not have their status assessed due to insufficient data). Progressors had shorter disease duration (median 8.1 vs 12.6 months, P=0.001) and lower mRSS (median 19 vs 21 units, P=0.030) than non-progressors. Skin score was highest, and peaked earliest, in the anti-RNA polymerase III (Pol3+) subgroup (n=50). A first predictive model (including mRSS, duration of skin thickening and their interaction) had an accuracy of 60.9%, AUC of 0.666 and PPV of 33.8%. By adding a variable for Pol3 positivity, the model reached an accuracy of 71%, AUC of 0.711 and PPV of 41%. CONCLUSIONS: Two prediction models for progressive skin thickening were derived, for use both in clinical practice and for cohort enrichment in RCTs. These models will inform recruitment into the many clinical trials of dcSSc projected for the coming years. TRIAL REGISTRATION NUMBER: NCT02339441.

Work productivity in systemic sclerosis, its economic burden and association with health-related quality of life.

Objective: To evaluate work productivity and its economic burden in SSc patients. Methods: Consecutive SSc patients enrolled in the Australian Scleroderma Cohort Study were mailed questionnaires assessing employment (Workers' Productivity and Activity Impairment Questionnaire and a custom-made questionnaire) and health-related quality of life (HRQoL) (36-item Short Form Health Survey and Patient-Reported Outcomes Measurement Information System 29). Linear regression methods were used to determine factors associated with work productivity. Results: Among 476 patients submitting responses, 55.2% <65 years of age were employed. Unemployed patients were older at the time of survey completion (57.1 vs 53.7 years; P < 0.001) and had longer disease duration from first SSc clinical manifestation (16.2 vs 14.9 years; P = 0.01) than employed patients. The mean age at unemployment onset was 13.2 years below the average Australian retirement age. Of those working in the week prior to completing the survey, 16.0% reported missing work (absenteeism) due to their SSc, accounting for 32.9% of their working week. Reduced productivity while at work (presenteeism) accounted for 22% of their working week. Annual costs per patient as a consequence of unemployment and reduced productivity equated to a total of AUD$67 595.40. Factors independently associated with reduced work productivity were presence of synovitis and sicca symptoms, while tertiary education protected against work impairment. Patients with low HRQoL scores also had low work productivity. Conclusion: SSc is associated with considerable unemployment and reduced productivity, which in turn is associated with a substantial economic burden and poor HRQoL. Raising awareness and identifying modifiable factors are possible ways of reducing this burden.