Prognostic and functional importance of both overt and subclinical left ventricular systolic dysfunction in systemic sclerosis.

OBJECTIVES: To quantify the frequency and clinical implications of systemic sclerosis (SSc)-associated left ventricular function (LV) impairment. METHODS: Australian Scleroderma Cohort Study participants meeting ACR/EULAR criteria for SSc with ≥1 echocardiographic LVEF measurement were included. Overt LV dysfunction was indicated by reduced LV ejection fraction (LVEF) and subclinical LV dysfunction was measured using impaired LV global longitudinal strain (LV-GLS>-16 %). Those with secondary causes of LV dysfunction (myocardial ischaemia, valvulopathy and pulmonary arterial hypertension) were excluded. Chi-squared tests, two-sample t-tests or Wilcoxon rank-sum tests were used for between-group comparison as appropriate. Generalised estimating equations(GEE) were used to model longitudinal data. Kaplan-Meier and Cox proportional hazard models were used for survival analyses. RESULTS: Of 1141 participants with no co-morbid cardiac disease, 2.4 % ever recorded a LVEF<50 %, while only 0.6 % ever recorded a LVEF≤40 %. LV-GLS data were available for 90 % of participants at one centre (n = 218). Impaired LV-GLS was detected in 21 % despite LVEF≥50 %. Those with a LVEF<50 % were more frequently male (p = 0.01) with dcSSc (p < 0.01), higher inflammatory markers (p < 0.02) and skeletal muscle disease (p < 0.05). In multivariable analyses, recording a LVEF<50 % was associated with increased mortality (HR2.3, 95 %CI1.0-4.8, p = 0.04). Impaired LV-GLS was also associated with poorer survival in univariable analyses (HR3.4, 95 %CI1.0-11.8, p = 0.05). Those with a LVEF<50 % more frequently recorded WHO Class III/IV dyspnoea (OR3.5, 95 %CI1.6-7.7, p < 0.01), with shorter six-minute walk distance (p = 0.01), higher Health Assessment Questionnaire-Disability Index scores (p < 0.01) and lower Short Form-36 Physical Component Summary scores (p = 0.02). Increased dyspnoea (WHO Class III/IV dyspnoea; OR3.6, 95 %CI1.4-9.2, p < 0.01) was also seen in those with impaired LV-GLS. CONCLUSIONS: Both overt and subclinical SSc-associated LV dysfunction are associated with worse survival and impaired physical function. The frequency of abnormal LV-GLS in those with consistently normal LVEF suggests an under-appreciated burden of subtle LV systolic dysfunction in SSc that has a significant impact on patient symptomatology.

Outcomes of Patients With Diffuse Systemic Sclerosis Eligible for Autologous Stem Cell Transplantation Treated With Conventional Therapy.

OBJECTIVE: The study objective was to determine the event-free survival (EFS) of Australian patients with diffuse cutaneous systemic sclerosis (dcSSc) who met eligibility criteria for autologous stem cell transplant (ASCT) in previously published randomized controlled trials but were not treated with ASCT. METHODS: Patients who met inclusion criteria for the Autologous Stem Cell Transplantation International Scleroderma (ASTIS) and Scleroderma: Cyclophosphamide Or Transplantation (SCOT) trials were identified from the multicenter Australian Scleroderma Cohort Study (ASCS). EFS (survival without cardiac, renal, or pulmonary failure or death) at 4 years was assessed. ASCS patients who had already undergone transplantation were excluded from analysis. RESULTS: Of the 492 patients with dcSSc in the ASCS, 56 met ASTIS inclusion criteria for ASCT (56 of 492 [11.4%]) and 30 met SCOT inclusion criteria (30 of 492 [6.1%]). An additional 11 patients met ASTIS or SCOT inclusion criteria, but they were excluded due to severe organ manifestations. EFS at 4 years in ASCS patients meeting ASTIS inclusion criteria was 83.3% and in ASCS patients meeting SCOT inclusion criteria was 81.2%. EFS at 4 years in ASCS patients who met ASTIS and SCOT inclusion but also exclusion criteria was 46.7% and 45.7%, respectively. CONCLUSION: ASCS patients meeting ASTIS and/or SCOT inclusion criteria who were not treated with ASCT have similar EFS at 4 years as patients receiving ASCT and better EFS than those receiving cyclophosphamide in the ASTIS and SCOT trials. This may reflect confounders unable to be controlled for, including survivor bias, but may also reflect improved standard of care for dcSSc over time.

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.

Evaluation of the European Society of Cardiology Risk Assessment Score in Incident Systemic Sclerosis-Associated Pulmonary Arterial Hypertension.

OBJECTIVE: Patients with pulmonary arterial hypertension (PAH) may be stratified as low, intermediate, or high risk of 1-year mortality. In 2022, the European Society of Cardiology (ESC) updated and simplified its risk stratification tool, based on three variables: World Health Organization functional class, serum N-terminal pro-brain type natriuretic peptide and six-minute walk distance, applied at follow-up visits, intended to guide therapy over time. METHODS: We applied the 2022 ESC risk assessment tool at baseline and follow-up (within 2 years) to a multinational incident cohort of systemic sclerosis-associated PAH (SSc-PAH). Kaplan-Meier curves, Cox hazards regression, and accelerated failure time models were used to evaluate survival by risk score. RESULTS: At baseline (n = 260), the majority of SSc-PAH (72.2%) were graded as intermediate risk of death according to the 2022 tool. At follow-up, according to 2022 tool, half (55.5%) of the cohort were classified as low or intermediate-low risk. The 2022 risk model at follow-up was able to differentiate survival between risk strata. All three individual parameters (World Health Organization functional class, N-terminal pro-brain type natriuretic peptide, six-minute walk distance) were significantly associated with mortality at baseline and/or follow-up. CONCLUSION: The 2022 ESC risk assessment strategy applied at baseline and follow-up predicts survival in SSc-PAH. Treatment decisions for SSc-PAH should include risk assessments, aiming to achieve low-risk status according to the 2022 ESC guidelines.

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.

Quantifying the need for specialist palliative care management in systemic sclerosis.

OBJECTIVE: The importance of early integration of palliative care in the management of complex multi-system diseases has been recognised. In this study, we aimed to quantify the need for specialist palliative care in systemic sclerosis (SSc). METHODS: Using data from 875 patients enrolled in the Australian Scleroderma Cohort Study, we defined need for palliative care as a high symptom burden at ≥2 consecutive study visits, ≥50% of overall study visits or at the study visit immediately prior to death. Symptoms of interest included breathlessness, fatigue, pain, depression, anxiety, constipation, and diarrhoea. Logistic regression analyses evaluated the association between individual symptoms and SSc manifestations. Linear regression analysis evaluated the relationship between palliative care needs and quality of life (QoL) and function. RESULTS: Almost three-quarters (72.69%) of patients met the threshold for specialist palliative care needs. Severe fatigue (54.17%) was most common, followed by breathlessness (23.66%) and severe constipation (21.14%). Concurrent severe symptoms were frequently observed. Severe breathlessness (coef -7.95, p<0.01) and pain (coef -7.70, p<0.01) were associated with the largest reductions in physical QoL. Severe mood symptoms were associated with the greatest reduction in mental QoL (coef -12.91, p<0.01). Severe pain (coef 0.56, p<0.01), breathlessness (coef 0.49, p<0.01) and mood symptoms (coef 0.40, p<0.01) had a significant impact on function. CONCLUSION: SSc is frequently associated with multiple severe symptoms that may be amenable to palliative care intervention. Given the strong association between symptom burden and impaired QoL targeted, effective symptom management in parallel with standard-of-care treatments may improve overall patient outcomes.

Proximal weakness and creatine kinase elevation in systemic sclerosis: Clinical correlates, prognosis and functional implications.

OBJECTIVES: To determine the frequency, clinical correlates and implications of clinical evidence of muscle disease in systemic sclerosis (SSc). METHODS: Australian Scleroderma Cohort Study participants with ≥1 creatine kinase (CK) and proximal power assessment were subdivided according to presence of proximal weakness (PW: proximal muscle power<5/5) and CK elevation(≥140IU/L). Participants were assigned to one of four groups: concurrent PW&CK elevation, PW alone, CK elevation alone or neither. Between-group comparisons were made with chi-squared, ANOVA or Kruskal-Wallis tests. Survival analysis was performed using time-varying-covariate Cox regression modelling. Longitudinal data were modelled using multinomial logistic and linear regression. RESULTS: Of 1786 participants, 4 % had concurrent PW&CK elevation, 15 % PW alone, 24 % CK elevation and 57 % neither. Participants with PW&CK elevation displayed a severe, inflammatory SSc phenotype, with more frequent dcSSc(p < 0.01), tendon friction rubs(p < 0.01), synovitis(p < 0.01) and digital ulceration(p = 0.03). Multimorbidity(p < 0.01) and cardiopulmonary disease, including ischaemic heart disease(p < 0.01) and pulmonary arterial hypertension(p < 0.01), were most common in those with PW, with and without CK elevation. Men with anti-Scl70 positivity most frequently had CK elevation alone, without other significant clinical differences. Multivariable modelling demonstrated 3.6-fold increased mortality in those with PW&CK elevation (95 %CI 1.9-6.6, p < 0.01) and 2.1-fold increased mortality in PW alone (95 %CI 1.4-3.0, p < 0.01) compared to those without PW or CK elevation. CK elevation alone conferred better survival (HR 0.7, 95 %CI 0.4-1.1, p = 0.09) compared to those with no PW or CK elevation. PW regardless of CK elevation was associated with impaired physical function, with reduced six-minute-walk-distance (p < 0.01), higher HAQ-DI scores (p < 0.01) and increased patient-reported dyspnoea (p = 0.04). CONCLUSION: Clinical features of myopathy are highly prevalent in SSc, affecting almost half of our study cohort. Detection of PW and elevated CK alone, even without imaging or histopathological identification of SSc-myopathy, identified important clinical associations and are associated with poorer function and overall prognosis.

Inflammatory Arthritis in Systemic Sclerosis: Its Epidemiology, Associations, and Morbidity.

OBJECTIVE: To describe the epidemiology, associations, and impact of inflammatory arthritis (IA) in systemic sclerosis (SSc). METHODS: Patients with SSc prospectively enrolled in the Australian Scleroderma Cohort Study were included. IA was defined clinically as the presence of synovitis on examination. Logistic regression was used to determine the associations of IA with SSc manifestations and serological parameters. Patient-reported outcome measures were used to capture physical function and health-related quality of life (HRQoL). RESULTS: IA was a common SSc manifestation affecting one-third (33.3%) of patients over a median follow-up of 4.3 (1.7-8.4) years. Associations of IA included diffuse SSc (odds ratio [OR] 1.33, 95% confidence interval [95% CI] 1.01-1.74, P = 0.042), concurrent musculoskeletal manifestations (joint contractures and tendon friction rubs, OR 1.70, 95% CI 1.34-2.15, P < 0.001); myositis (OR 2.11, 95% CI 1.39-3.20, P < 0.001), and sicca symptoms (OR 1.57, 95% CI 1.14-2.16, P = 0.006), whereas IA was negatively associated with pulmonary arterial hypertension (OR 0.52, 95% CI 0.35-0.78, P = 0.002). Neither the presence of rheumatoid factor nor U1 small nuclear RNP were associated with IA (OR 1.13, 95% CI 0.88-1.44, P = 0.331, OR 1.46, 95% CI 0.89-2.39, P = 0.129 respectively). Positive anticyclic citrullinated protein antibodies, although at low frequency, were more common in those with IA compared with those without IA (7.5% vs 1.5%, P < 0.001). IA was associated with significantly lower HRQoL score (P < 0.001) and more physical disability than in those without IA (P < 0.001). CONCLUSION: IA is a common disease manifestation that is more frquently seen in diffuse disease. IA is associated with poor HRQoL and physical disability. Further research is needed into the effective management of IA in SSc.

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.

Impact of the COVID-19 Pandemic on Health Care Access and Diagnosis of Pulmonary Arterial Hypertension Among Patients With Systemic Sclerosis.

OBJECTIVE: Regular clinical assessment for complications of systemic sclerosis (SSc) such as pulmonary arterial hypertension (PAH) is essential for early institution of therapy and improved outcomes. The objective of this study was to determine the impact of COVID-19 pandemic-related restrictions on health care access of patients with SSc, including screening for PAH. METHODS: South Australian and Victorian patients enrolled in the Australian Scleroderma Cohort Study were surveyed about their perceptions of the impact of the pandemic on mental well-being, access to medications, investigations, and management of SSc. Frequency of annual rheumatology assessments, pulmonary function tests (PFT), and transthoracic echocardiography (TTE) to screen for PAH were compared with rates from before the pandemic. RESULTS: A total of 312 of 810 patients with SSc responded (38.5% response); 273 were female (87.5%), the median age was 64.7 years, 77.2% had limited disease, the median illness duration was 15.6 years, 15.7% were immunosuppressed, 32.1% had interstitial lung disease, and 6.4% had PAH. A total of 65.7% of consultations were by telehealth, of which 81.2% were by telephone. Compared with respondents in South Australia (n = 109), Victorian respondents (n = 203) experiencing prolonged lockdown, reported reduced access to their rheumatologist (49.3% vs 27.9%; P = 0.004), greater use of consultation by video (17.3% vs 2.1%; P = 0.008), greater health care disruption (49.0% vs 23.2%; P < 0.001), and worse mental health (P = 0.002). Respondents reported reduced access to PFT and TTE (31.7% and 22.5%, respectively). Annual visits, PFT, TTE, and new diagnoses of PAH were reduced in 2020 to 2022 compared with 2011 to 2019. CONCLUSION: The COVID-19 pandemic-related disruption to health care for patients with SSc was associated with worse mental health and reduced screening and diagnosis of PAH, which may impact long-term outcomes.

The effect of calcium channel blockers on digital ulcers in systemic sclerosis: data from a prospective cohort study.

Digital ulcers (DU) are a common, severe vascular manifestation of systemic sclerosis (SSc) with few effective treatment options. Using data from the Australian Scleroderma Cohort Study (ASCS), we sought to evaluate the effect of calcium channel blockers (CCB) on the treatment and prevention of DU.Using data from 1953 participants, with a median of 4.34 years of follow-up, we used generalised estimating equations to evaluate the clinical characteristics associated with CCB use and ascertain the risk factors for the presence of DU at subsequent study visits. A time-dependent Cox-proportional hazard model was applied to evaluate the risk of future occurrence of DU with CCB use.Sixty-six percent of participants received CCB and patients with a history of DU were more likely to be prescribed a CCB (76.76% vs 53.70%, p < 0.01). CCB use was more frequent in patients with severe complications of DU including chronic DU (OR 1.47, p = 0.02), need for hospitalisation for iloprost (OR 1.30, p = 0.01) or antibiotics (OR 1.36, p = 0.04) and digital amputation (OR 1.48, p < 0.01). Use of CCB was more likely in patients who experienced DU at subsequent study visits (OR 1.32, p < 0.01) and was not associated with a decreased risk of the development of a first DU (HR 0.94, p = 0.65).CCB are frequently used in the management of SSc in the ASCS and their use is associated with severe peripheral vascular manifestations of SSc. However, our results suggest that CCB may not be effective in the healing or prevention of DU.

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.

Clinical characteristics and survival of pulmonary arterial hypertension with or without interstitial lung disease in systemic sclerosis.

OBJECTIVES: To describe the clinical phenotype and prognosis of people in the Australian Scleroderma (SSc) Cohort Study with pulmonary arterial hypertension (PAH) with or without interstitial lung disease (ILD). METHODS: Participants meeting ACR/EULAR criteria for SSc were divided into four mutually exclusive groups: those meeting criteria for PAH (PAH-only), ILD (ILD-only), concurrent PAH and ILD (PAH-ILD) or neither PAH nor ILD (SSc-only). Logistic or linear regression analyses were used for associations between clinical features, health-related quality of life (HRQoL) and physical function. Survival analysis was performed using Kaplan-Meier estimates and Cox-regression modelling. RESULTS: Of 1561 participants, 7% fulfilled criteria for PAH-only, 24% ILD-only, 7% PAH-ILD and 62% SSc-only. People with PAH-ILD were more frequently male, with diffuse skin involvement, higher inflammatory markers, older age of SSc onset and higher frequency of extensive ILD than the cohort overall (p < 0.001). People of Asian race more frequently developed PAH-ILD (p < 0.001). People with PAH-ILD or PAH-only had worse WHO functional class and 6-min-walk-distance than ILD-only (p < 0.001). HRQoL scores were worst in those with PAH-ILD (p < 0.001). Survival was reduced in the PAH-only and PAH-ILD groups (p < 0.01). Multivariable hazard modelling demonstrated the worst prognosis in extensive ILD and PAH (HR = 5.65 95% CI 3.50-9.12 p < 0.01), followed by PAH-only (HR = 4.21 95% CI 2.89-6.13 p < 0.01) and PAH with limited ILD (HR = 2.46 95% CI 1.52-3.99 p < 0.01). CONCLUSIONS: The prevalence of concurrent PAH-ILD in the ASCS is 7%, with poorer survival in those patients with PAH-ILD compared to ILD or SSc alone. The presence of PAH confers a poorer overall prognosis than even extensive ILD; however, further data are required to better understand the clinical outcomes of this high-risk patient group.

A Composite Serum Biomarker Index for the Diagnosis of Systemic Sclerosis-Associated Interstitial Lung Disease: A Multicenter, Observational Cohort Study.

OBJECTIVE: In patients with systemic sclerosis (SSc), we investigated composite serum biomarker panels for the diagnosis and risk stratification of SSc-associated interstitial lung disease (SSc-ILD). METHODS: We analyzed 28 biomarkers in 640 participants: 259 patients with SSc-ILD and 179 SSc patients without ILD (Australian Scleroderma Cohort Study), 172 patients with idiopathic pulmonary fibrosis (IPF-controls) (Australian IPF Registry), and 30 healthy controls. A composite index was developed from biomarkers associated with ILD in multivariable analysis derived at empirical thresholds. We evaluated the performance of the index to identify ILD, and specifically SSc-ILD, and its association with lung function, disease extent on radiography, and patient health-related quality of life in derivation and validation cohorts. Biomarkers to distinguish SSc-ILD from IPF-controls were identified. RESULTS: A composite biomarker index, comprising surfactant protein D (SP-D), Ca15-3, and intercellular adhesion molecule 1 (ICAM-1), was strongly associated with SSc-ILD diagnosis, independent of age, sex, smoking history, and lung function (for biomarker index score 3, pooled adjusted odds ratio was 12.72 (95% confidence interval 4.59-35.21) (P < 0.001). The composite index strengthened the performance of individual biomarkers for SSc-ILD identification. In SSc patients, a higher index was associated with worse baseline disease severity (for biomarker index score 3 relative to biomarker index score 0, the adjusted absolute change in forced vital capacity percent predicted was -17.84% and the diffusing capacity for carbon monoxide percent predicted was -20.16%; both P < 0.001). CONCLUSION: A composite serum biomarker index, comprising SP-D, Ca15-3, and ICAM-1, may improve the identification and risk stratification of ILD in SSc patients at baseline.

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.

Damage Trajectories in Systemic Sclerosis Using Group-Based Trajectory Modeling.

OBJECTIVE: Systemic sclerosis (SSc) is an autoimmune disease characterized by progressive organ damage, which can be measured using the Scleroderma Clinical Trials Consortium Damage Index (SCTC-DI). We aimed to identify whether distinct trajectories of damage accrual exist and to determine which variables are associated with different trajectory groups. METHODS: Incident cases of SSc (<2 years) were identified in the Australian Scleroderma Interest Group and Canadian Scleroderma Research Group prospective registries. Group-based trajectory modeling was used to identify SCTC-DI trajectories over the cohort's first 5 annual visits. Baseline variables associated with trajectory membership in a univariate analysis were examined in multivariable models. RESULTS: A total of 410 patients were included. Three trajectory groups were identified: low (54.6%), medium (36.2%), and high (10.3%) damage. Patients with faster damage accrual had higher baseline SCTC-DI scores. Older age (odds ratio [OR] 1.57 [95% confidence interval (95% CI) 1.18-2.10]), male sex (OR 2.55 [95% CI 1.10-5.88]), diffuse disease (OR 6.7 [95% CI 2.57-17.48]), tendon friction rubs (OR 5.4 [95% CI 1.86-15.66]), and elevated C-reactive protein level (OR 1.98 [95% CI 1.49-2.63]) increased the odds of being in the high-damage group versus the reference (low damage), whereas White ethnicity (OR 0.31 [95% CI 0.12-0.75]) and anticentromere antibodies (OR 0.24 [95% CI 0.07-0.77]) decreased the odds. CONCLUSION: We identified 3 trajectories of damage accrual in a combined incident SSc cohort. Several characteristics increased the odds of belonging to worse trajectories. These findings may be helpful in recognizing patients in whom early aggressive treatment is necessary.

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.