Determining progression of scleroderma-related interstitial lung disease

Untangling the relationship between smoking and systemic sclerosis: an analysis of the EUSTAR cohort

OBJECTIVES

To untangle the association between smoking and systemic sclerosis (SSc).

METHODS

In the European Scleroderma Trials and Research cohort, the autoantibody status was compared between ever-smokers and never-smokers. Time until disease progression was assessed using Kaplan-Meier curves. Cox models were built to investigate the influence of smoking over 15 years of follow-up. All analyses were performed for the total cohort and stratified for sex and for positivity of anti-centromere (ACA) and anti-topoisomerase antibodies (ATA).

RESULTS

Overall, 12 314 patients were included in the study. Of these, 10 393 were women (84%), 4637 were ACA-positive (38%), 3919 were ATA-positive (32%) and 4271 (35%) were ever-smokers. In men, but not in women, smoking was associated with mortality (HR 1.63, 95% CI 1.23 to 2.16, p=0.001). Ever-smoking women were at higher risk for skin progression (HR 1.10, 95% CI 1.00 to 1.22, p=0.046) and for 'any organ progression' (HR 1.07, 95% CI 1.00 to 1.13, p=0.036). In women, 34% of never-smokers were ATA-positive compared with 21% of ever-smokers (p<0.001). In the group of ever-smokers, higher exposure rates, reflected by the number of pack-years (OR 0.98, 95% CI 0.97 to 0.99, p<0.001) and by smoking duration (OR 0.96, 95% CI 0.95 to 0.97, p<0.001), were associated with lower frequency of ATA. In ACA-positive patients, the risk of mortality (HR 1.29, 95% CI 1.02 to 1.63, p=0.033), cardiac involvement (HR 1.25, 95% CI 1.03 to 1.43, p=0.001), skin progression (HR 1.21, 95% CI 1.03 to 1.42, p=0.018) and 'any organ progression' (HR 1.14, 95% CI 1.05 to 1.24, p=0.002) was increased among smokers. In ATA-positive smoking patients, mortality (HR 1.40, 95% CI 1.10 to 1.78, p=0.006), skin progression (HR 1.19, 95% CI 1.03 to 1.37, p=0.020) digital ulcers (HR 1.17, 95% CI 1.02 to 1.34, p=0.029) and 'any organ progression' (HR 1.11, 95% CI 1.00 to 1.22, p=0.048) occurred more frequently.

CONCLUSIONS

Our stratified analysis demonstrates that smoking is associated with an increased risk for mortality in male SSc patients but not in women. Strikingly, smoking is associated with lower prevalence of ATA positivity, in particular in women. In both ATA-positive and ACA-positive patients, smoking is a risk factor for mortality, skin progression and 'any organ progression'.

Sex influence on outcomes of patients with systemic sclerosis-associated interstitial lung disease: a EUSTAR database analysis

OBJECTIVE

Interstitial lung disease (ILD) is the leading cause of morbidity and mortality in systemic sclerosis (SSc) patients. We aimed to investigate the impact of sex on SSc-ILD.

METHODS

EUSTAR SSc patients with radiologically confirmed ILD and available percentage predicted forced vital capacity (%pFVC) were included. Demographics and disease features were recorded. A change in %pFVC over 12 months (s.d. 6) (cohort 1) was classified into stable (≤4%), mild (5-9%) and large progression (≥10%). In those with 2-year longitudinal %pFVC (cohort 2), the %pFVC change at each 12-month (s.d. 6) interval was calculated. Logistic regression analyses [odds ratio (OR) and 95% CI] and Cox proportional hazards models adjusted for age and %pFVC were applied.

RESULTS

A total of 1136 male and 5253 female SSc-ILD patients were identified. Males were significantly younger, had a shorter disease duration, had a higher prevalence of CRP elevation and frequently had diffuse cutaneous involvement. In cohort 1 (1655 females and 390 males), a higher percentage of males had stable ILD (74.4% vs 69.4%, P = 0.056). In multivariable analysis, disease duration and %pFVC [OR 0.99 (95% CI 0.98, 0.99) and OR 0.97 (95% CI 0.95, 0.99), respectively] in males and age, %pFVC and anti-centromere [OR 1.02 (95% CI 1.00, 1.04), OR 0.97 (95% CI 0.96, 0.98) and OR 0.39 (95% CI 0.245, 0.63), respectively] in females were associated with large progression. The 1-year mortality rate was higher in males (5.1% vs 2.5%, P = 0.013). In cohort 2 (849 females and 209 males), a higher percentage of females showed periods of large progression (11.7% vs 7.7%, P = 0.023), the percentage of patients with none, one or two periods of worsening was not different. The overall death rate was 30.9% for males and 20.4% in females (P < 0.001). In the survival analysis, male sex was a predictor of mortality [OR 1.95 (95% CI 1.66, 2.28)].

CONCLUSIONS

Male SSc-ILD patients have a poorer prognosis and sex-specific predictors exist in SSc-ILD.

Risk Factors for Respiratory Failure in Patients Hospitalized With Systemic Sclerosis: An Analysis of the National Inpatient Sample

Background Systemic sclerosis (SSc) patients are at high risk for respiratory failure due to the progression of their disease. Investigating factors predictive of impending respiratory failure in this patient population can be used to improve hospital outcomes. Here, we investigate risk factors associated with developing respiratory failure in patients hospitalized with a diagnosis of SSc in the United States using a large, multi-year, population-based dataset. Methodology This retrospective study was conducted on SSc hospitalizations from 2016 to 2019 with and without a principal diagnosis of respiratory failure from the United States National Inpatient Sample database. A multivariate logistic regression analysis was performed to calculate adjusted odds ratios (OR_adj) for respiratory failure. Results There were 3,930 SSc hospitalizations with a principal diagnosis of respiratory failure and 94,910 SSc hospitalizations without a diagnosis of respiratory failure. Among SSc hospitalizations, multivariable analysis showed that the following were associated with a principal diagnosis of respiratory failure: Charlson comorbidity index (OR_adj = 1.05), heart failure (OR_adj = 1.81), interstitial lung disease (ILD) (OR_adj = 3.62), pneumonia (OR_adj = 3.40), pulmonary hypertension (OR_adj = 3.59), and smoking (OR_adj = 1.42). Conclusions This analysis represents the largest sample to date in assessing risk factors for respiratory failure among SSc inpatients. Charlson comorbidity index, heart failure, ILD, pulmonary hypertension, smoking, and pneumonia were associated with higher odds of inpatient respiratory failure. Patients with respiratory failure had higher in-hospital mortality compared to those without it. Outpatient optimization and inpatient recognition of these risk factors can lead to improved hospitalization outcomes for SSc patients.

Lung vascular changes as biomarkers of severity in systemic sclerosis-associated interstitial lung disease

OBJECTIVES

It has recently become possible to assess lung vascular and parenchymal changes quantitatively in thoracic CT images using automated software tools. We investigated the vessel parameters of patients with SSc, quantified by CT imaging, and correlated them with interstitial lung disease (ILD) features.

METHODS

SSc patients undergoing standard of care pulmonary function testing and CT evaluation were retrospectively evaluated. CT images were analysed for ILD patterns and total pulmonary vascular volume (PVV) extents with Imbio lung texture analysis. Vascular analysis (volumes, numbers and densities of vessels, separating arteries and veins) was performed with an in-house developed software. A threshold of 5% ILD extent was chosen to define the presence of ILD, and commonly used cut-offs of lung function were adopted.

RESULTS

A total of 79 patients [52 women, 40 ILD, mean age 56.2 (s.d. 14.2) years, total ILD extent 9.5 (10.7)%, PVV/lung volume % 2.8%] were enrolled. Vascular parameters for total and separated PVV significantly correlated with functional parameters and ILD pattern extents. SSc-associated ILD (SSc-ILD) patients presented with an increased number and volume of arterial vessels, in particular those between 2 and 4 mm of diameter, and with a higher density of arteries and veins of <6 mm in diameter. Considering radiological and functional criteria concomitantly, as well as the descriptive trends from the longitudinal evaluations, the normalized PVVs, vessel numbers and densities increased progressively with the increase/worsening of ILD extent and functional impairment.

CONCLUSION

In SSc patients CT vessel parameters increase in parallel with ILD extent and functional impairment, and may represent a biomarker of SSc-ILD severity.

Minimal Clinically Important Differences (MCID) for the Functional Assessment of Chronic Illness Therapy Fatigue Scale in Patients with Systemic Sclerosis

(1) Background: Systemic sclerosis (SSc) is characterized by significant fatigue, causing diminished quality of life (QoL). The aim of this study was to examine fatigue levels and their associations with clinical factors and determine the minimal clinically important difference (MCID) value for the Functional Assessment of Chronic Illness Therapy Fatigue Scale (FACIT-FS). (2) Methods: A total of 160 SSc patients and 62 individuals without SSc were followed-up over a 12-month period by measuring the FACIT-FS and the Visual Analogue Scale and the Short Form 36 Vitality Score analyzing changes in exhaustion. (3) Results: Fatigue was strongly correlated with HRQoL, level of pain, emotional disorders, physical capability and functionality. The MCID values for FACIT-FS were calculated as -3 for deterioration and +4 for improvement after a 12-month follow-up. The predictors of improvement of fatigue from baseline parameters were the significant disease activity, the patients' poorer functionality and the short disease duration. Patients with scleroderma-related interstitial lung disease at baseline had approximately tripled risks for worsening fatigue. The independent influential factors regarding the changing of FACIT-FS were improving or worsening in the same direction in reference to physical condition, gastrointestinal and emotional factors. (4) Conclusions: Fatigue is a multi-dimensional symptom, which is strongly correlated to HRQoL. MCID values of FACIT-FS can be useful tools in monitoring the changes of HRQoL in clinical trials and in daily practice among patients with SSc.

Clinical and radiological features of lung disorders related to connective-tissue diseases: a pictorial essay

Connective tissue diseases (CTDs) include a spectrum of disorders that affect the connective tissue of the human body; they include autoimmune disorders characterized by immune-mediated chronic inflammation and the development of fibrosis. Lung involvement can be misdiagnosed, since pulmonary alterations preceded osteo-articular manifestations only in 20% of cases and they have no clear clinical findings in the early phases. All pulmonary structures may be interested: pulmonary interstitium, airways, pleura and respiratory muscles. Among these autoimmune disorders, rheumatoid arthritis (RA) is characterized by usual interstitial pneumonia (UIP), pulmonary nodules and airway disease with air-trapping, whereas non-specific interstitial pneumonia (NSIP), pulmonary hypertension and esophageal dilatation are frequently revealed in systemic sclerosis (SSc). NSIP and organizing pneumonia (OP) may be found in patients having polymyositis (PM) and dermatomyositis (DM); in some cases, perilobular consolidations and reverse halo-sign areas may be observed. Systemic lupus erythematosus (SLE) is characterized by serositis, acute lupus pneumonitis and alveolar hemorrhage. In the Sjögren syndrome (SS), the most frequent pattern encountered on HRCT images is represented by NSIP; UIP and lymphocytic interstitial pneumonia (LIP) are reported with a lower frequency. Finally, fibrotic NSIP may be the interstitial disease observed in patients having mixed connective tissue diseases (MCTD). This pictorial review therefore aims to provide clinical features and imaging findings associated with autoimmune CTDs, in order to help radiologists, pneumologists and rheumatologists in their diagnoses and management.

Quality of life in SSc-ILD patients: Understanding the impact of the ILD and the needs of the SSc-ILD patients and their need for caregivers in France

Objectives

The objectives of this study were to describe the impact of systemic sclerosis associated interstitial lung disease, on quality of life, to estimate the correlation between quality of life and severity of lung disease and to assess the impact of interstitial lung disease on caregivers.

Methods

Seven investigators included systemic sclerosis associated interstitial lung disease patients from December 2019 to April 2020. Sociodemographics and clinical data were collected. Patients reported outcomes and questionnaires were used with 1 generic patients reported outcome (EQ-5D-5L), 1 specific PRO (Brief Interstitial Lung Disease) and 2 self-reported questionnaires on impact of SSc complications and impact on caregivers. The correlation between forced vital capacity and EQ-5D-5L score was estimated with a multivariate linear regression model adjusted on several covariates.

Results

In all, 89 patients were included. 26.4% were males, mean age was 58.2 ± 14.5 years. Mean EQ-5D-5L score = 0.79 ± 0.22 (median = 0.85). Mean EQ-5D-5L visual analog scale score = 60.8 ± 20.4 (median = 61.5). Mean King's Brief Interstitial Lung Disease score = 58.4 ± 12.7 (median = 58.0). After adjustment on covariates, a significant correlation between forced vital capacity and EQ-5D-5L score was found with an increase of 0.003 of the EQ-5D-5L score for a 1% increase of FVC (p = 0.0096). No significant correlation between forced vital capacity and the EQ-VAS and King's Brief Interstitial Lung Disease score were found. The impact of SSc on other organs was significantly correlated with EQ- 5D-5L score, respectively, for the impact scores on the lung system (p = 0.0003), heart system (p = 0.0182), Raynaud's syndrome (p = 0.0015), digestive system (p = 0.0032), joints/muscles (p = 0.0003), skin (p < 0.0001), kidney (p = 0.0052) and gastro-oesophageal reflux (p = 0.0063). Significant correlations between King's Brief Interstitial Lung Disease score and lung system (p < 0.0001), heart system (p < 0.0001), digital ulcers (p = 0.058), digestive system (p < 0.0001), kidney (p = 0.0004), skin (p = 0.0499) and gastro-oesophageal reflux (p = 0.0033) scores were found 68.5% of patients reported their need for a caregiver to help them in their daily life activities.

Conclusion

Our study highlighted the strong burden of systemic sclerosis associated interstitial lung disease` for patients, especially with an impact on quality of life, on other organs manifestations and need for caregivers in their daily life.

Anti-Ro52/TRIM21 is independently associated with pulmonary arterial hypertension and mortality in a cohort of systemic sclerosis patients

Objective: We undertook a comprehensive cross-sectional analysis of a multicentred Australian cohort of systemic sclerosis (SSc) patients to evaluate the associations of anti-Ro52/TRIM21 with SSc pulmonary involvement.Method: The study included 596 patients from the Australian Scleroderma Cohort Study database whose anti-Ro52/TRIM21 status was known. Anti-Ro52/TRIM21 was measured via line immunoassay. Data on demographic variables, autoantibody profiles, presence of interstitial lung disease (ILD), presence of pulmonary arterial hypertension (PAH), oxygen saturation, Six-Minute Walk Test distance, Borg dyspnoea score, and lung function tests were extracted. SPSS software was used to examine associations using univariate and multivariate analyses.Results: Anti-Ro52/TRIM21 was present in 34.4% of SSc patients. In the cross-sectional analysis, anti-Ro52/TRIM21 was independently associated with PAH [odds ratio 1.75, 95% confidence interval (CI) 1.05-2.90], but not ILD or other surrogate measures of pulmonary involvement such as average patient oxygen saturation. The antibody, however, was also associated with a higher forced vital capacity/diffusing capacity of the lung for carbon monoxide ratio. Prospectively, anti-Ro52/TRIM21 was also associated with an increased risk of death in patients with SSc (hazard ratio 1.62, 95% CI 1.11-2.35), independent of confounding factors. The primary cause of death appeared to be related to PAH and/or ILD, and anti-Ro52/TRIM21 was associated with PAH-related complications.Conclusion: Anti-Ro52/TRIM21 was independently associated with PAH and mortality in SSc patients. Future longitudinal studies are recommended to investigate the timing and pathogenic mechanisms of this autoantibody in PAH.

The Treatment of Lung Involvement in Systemic Sclerosis

Systemic sclerosis (SSc) patients are often affected by interstitial lung disease (ILD) and, although there have been recent treatment advances, it remains the leading cause of death among SSc, with a 10-year mortality up to 40%. African Americans and subjects with diffuse cutaneous SSc or anti-topoisomerase 1 antibodies are most commonly affected. Currently, early ILD diagnosis can be made, and it is pivotal to improve the prognosis. The diagnostic mainstay test for SSc-ILD is high-resolution computed tomography for the morphology and pulmonary function tests for the functional aspects. Treatment planning and intensity are guided by the disease severity and risk of progression. Traditionally, therapy has depended on combinations of immunosuppressants, particularly cyclophosphamide and mycophenolate mofetil, which can be supplemented by targeted biological and antifibrotic therapies. Benefits have been observed in trials on hematopoietic autologous stem cell transplantation for patients with progressive SSc, whilst lung transplantation is reserved for refractory SSc-ILD cases. Herein, recent advances in SSc-ILD treatment will be explored.

Using Transitional Changes on High-Resolution Computed Tomography to Monitor the Impact of Cyclophosphamide or Mycophenolate Mofetil on Systemic Sclerosis-Related Interstitial Lung Disease

OBJECTIVE

To examine changes in the extent of specific patterns of interstitial lung disease (ILD) as they transition from one pattern to another in response to immunosuppressive therapy in systemic sclerosis-related ILD (SSc-ILD).

METHODS

We evaluated changes in the quantitative extent of specific lung patterns of ILD using volumetric high-resolution computed tomography (HRCT) scans obtained at baseline and after 2 years of therapy in patients treated with either cyclophosphamide (CYC) for 1 year or mycophenolate mofetil (MMF) for 2 years in Scleroderma Lung Study II. ILD patterns included lung fibrosis, ground glass, honeycombing, and normal lung. Net change was calculated as the difference in the probability of change from one ILD pattern to another. Wilcoxon's signed rank test was used to compare the changes.

RESULTS

Forty-seven and 50 patients had baseline and follow-up scans in the CYC and MMF groups, respectively. Mean net improvements reflecting favorable changes from one ILD pattern to another in the whole lung in the CYC and MMF groups, respectively, were as follows: from lung fibrosis to a normal lung pattern, 21% and 19%; from a ground-glass pattern to a normal lung pattern, 30% and 28%; and from lung fibrosis to a ground-glass pattern, 5% and 0.5%. The mean overall improvement in transitioning from a ground-glass pattern or lung fibrosis to a normal lung pattern was significant for both treatments (all P < 0.001).

CONCLUSION

Significantly favorable transitions from both ground-glass and lung fibrosis ILD patterns to a normal lung pattern were observed in patients undergoing immunosuppressive treatment for SSc-ILD, suggesting the usefulness of examining these transitions for insights into the underlying pathobiology of treatment response.

Natural History of Systemic Sclerosis-Related Interstitial Lung Disease: How to Identify a Progressive Fibrosing Phenotype

The natural history of interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) is highly variable. Historical observational studies have demonstrated that the greatest decline in lung function in SSc occurs early in the course of the disease; however, not all patients experience a decline in lung function even in the absence of treatment. Furthermore, among patients who do experience a decline in lung function, the rate of decline can be either rapid or slow. The most common clinical phenotypes of SSc-ILD therefore: (i) Rapid Progressors, (ii) Gradual Progressors, (iii) Stabilizers and (iv) Improvers. This review summarizes the features of SSc-ILD patients who are more likely to experience rapid progression of ILD, as well as those who are more likely not to experience ILD progression. Understanding the clinical, biological and radiographic factors that consistently predict ILD-related outcomes in SSc is central to our ability to recognize those patients who are at heightened risk for ILD progression. With new options available for treating patients with SSc-ILD, it is more important than ever to accurately identify patients who may derive the most benefit from aggressive SSc-ILD therapy. Early therapeutic intervention in patients with this progressive fibrosing phenotype may ultimately improve morbidity and mortality outcomes in patients with SSc-ILD.

Progression of Interstitial Lung Disease in Systemic Sclerosis: The Importance of Pneumoproteins Krebs von den Lungen 6 and CCL18

OBJECTIVE

To investigate the relationship between Krebs von den Lungen 6 (KL-6) and CCL18 levels and the severity and progression of systemic sclerosis (SSc)-related interstitial lung disease (ILD).

METHODS

Patients enrolled in the Scleroderma Lung Study II (cyclophosphamide [CYC] versus mycophenolate mofetil [MMF]) were included. Baseline and 12-month plasma samples were analyzed by enzyme-linked immunosorbent assay to assess CCL18 and KL-6 levels. The forced vital capacity (FVC) and the diffusing capacity for carbon monoxide (DLco) were measured every 3 months. Joint models were created to investigate the relationship between baseline CCL18 and KL-6 levels and the course of the FVC and DLco over 1 year according to treatment arm.

RESULTS

Baseline KL-6 and CCL18 levels each correlated with the extent of radiographic fibrosis. Levels of both CCL18 and KL-6 declined significantly at 1 year. In both treatment arms (n = 71 for CYC, n = 62 for MMF), a higher baseline KL-6 level predicted progression of ILD based on the course of FVC (P = 0.024 for CYC; P = 0.005 for MMF) and DLco (P < 0.001 for CYC; P = 0.004 for MMF) over 1 year. A higher baseline CCL18 level predicted progression of ILD based on the course of the FVC (P < 0.001 for CYC; P = 0.007 for MMF) and DLco (P = 0.001 for CYC; P < 0.001 for MMF) over 1 year, as well as mortality (P = 0.0008 for CYC arm only).

CONCLUSION

In a rigorously conducted clinical trial for SSc-related ILD, KL-6 and CCL18 levels correlated with ILD severity and declined with immunosuppression. Patients with higher baseline KL-6 and CCL18 levels were more likely to experience disease progression despite treatment. KL-6 and CCL18 levels could be used to identify patients with a progressive ILD phenotype who may benefit from a more aggressive initial treatment approach.