Interstitial lung disease in systemic sclerosis: challenges in early diagnosis and management

Systemic sclerosis associated interstitial lung disease: a survey of current practices in France

Background

Interstitial lung disease (ILD) is the leading cause of mortality in systemic sclerosis (SSc).

Objective

We performed an overview of the diagnostic approaches, follow-up and treatment strategies used in France for the management of SSc-associated ILD (SSc-ILD).

Design Structured nationwide online surveyMethods

A structured nationwide online survey was submitted to participants via the French Medical Societies for Internal Medicine and Pneumology, and research groups on SSc-ILD from May 2018 to June 2020. The 79 multiple-choice and 9 open-ended questions covered the screening of ILD at baseline, monitoring of patients with established SSc-ILD and its management. Fourteen optional vignettes exploring different clinical phenotypes of SSc-ILD were submitted to evaluate therapeutic decisions.

Results

All of the 93 participants screened SSc patients for ILD at baseline with 83 (89%) participants relying on a systematic chest computed tomography (CT) scan. Pulmonary function tests (PFT) were prescribed by 87 (94%) participants at baseline and during follow-up. Treatment was started based on abnormal PFT (95%), chest CT scan characteristics (89%), worsening dyspnoea (72%) and drop in SpO₂ during 6-min walk tests (66%). First-line therapy was cyclophosphamide (CYC) (89%), mycophenolate mofetil (MMF) (83%) and prednisone (73%). Rituximab as second-line immunosuppressive therapy (41%) was preferred to antifibrotic agents (18%), and a median daily prednisone dose of 10 mg (interquartile range, 10-15) was prescribed by 73% participants. Extensive SSc-ILD with worsening PFT (95%), regardless of diffusing capacity for carbon monoxide values and skin extension, were more likely to be treated, and CYC was favoured over MMF (p < 0.01). Extensive SSc-ILD with disease duration of less than 5 years was also a criterium for treatment initiation.

Conclusion

This overview of practices in diagnosis, follow-up and treatment of SSc-ILD in France describes real-life management of patients. It highlights heterogeneity in this management and gaps in current strategies that should be addressed to improve and harmonize clinical practices in SSc-ILD.

Assessment of disease outcome measures in systemic sclerosis

The assessment of disease activity in systemic sclerosis (SSc) is challenging owing to its heterogeneous manifestations across multiple organ systems, the variable rate of disease progression and regression, and the relative paucity of patients in early-phase therapeutic trials. Despite some recent successes, most clinical trials have failed to show efficacy, underscoring the need for improved outcome measures linked directly to disease pathogenesis, particularly applicable for biomarker studies focused on skin disease. Current outcome measures in SSc-associated interstitial lung disease and SSc skin disease are largely adequate, although advancing imaging technology and the incorporation of skin mRNA biomarkers might provide opportunities for earlier detection of the therapeutic effect. Biomarkers can further inform pathogenesis, enabling early phase trials to act as reverse translational studies through the incorporation of routine high-throughput sequencing.

Systemic Scleroderma-Definition, Clinical Picture and Laboratory Diagnostics

(1) Background: Scleroderma (Sc) is a rare connective tissue disease classified as an autoimmune disorder. The pathogenesis of this disease is not fully understood. (2) Methods: This article reviews the literature on systemic scleroderma (SSc). A review of available scientific articles was conducted using the PubMed database with a time range of January 1985 to December 2021. (3) Results and Conclusions: The article is a review of information on epidemiology, criteria for diagnosis, pathogenesis, a variety of clinical pictures and the possibility of laboratory diagnostic in the diagnosis and monitoring of systemic scleroderma.

Patient preferences for the treatment of systemic sclerosis-associated interstitial lung disease: a discrete choice experiment

Objectives

Treatments for SSc-associated interstitial lung disease (SSc-ILD) differ in attributes, i.e. mode of administration, adverse events (AEs) and efficacy. As physicians and patients may perceive treatments differently, shared decision-making can be essential for optimal treatment provision. We therefore aimed to quantify patient preferences for different treatment attributes.

Methods

Seven SSc-ILD attributes were identified from mixed-methods research and clinician input: mode of administration, shortness of breath, skin tightness, cough, tiredness, risk of gastrointestinal AEs (GI-AEs) and risk of serious and non-serious infections. Patients with SSc-ILD completed an online discrete choice experiment (DCE) in which they were asked to repeatedly choose between two alternatives characterized by varying severity levels of the included attributes. The data were analysed using a multinomial logit model; relative attribute importance and maximum acceptable risk measures were calculated.

Results

Overall, 231 patients with SSc-ILD completed the DCE. Patients preferred twice-daily oral treatments and 6–12 monthly infusions. Patients’ choices were mostly influenced by the risk of GI-AEs or infections. Improvement was more important in respiratory symptoms than in skin tightness. Concerning trade-offs, patients accepted different levels of increase in GI-AE risk: +21% if it reduced the infusions’ frequency; +15% if changing to an oral treatment; up to +37% if it improved breathlessness; and up to +36% if it reduced the risk of infections.

Conclusions

This is the first study to quantitatively elicit patients’ preferences for treatment attributes in SSc-ILD. Patients showed willingness to make trade-offs, providing a firm basis for shared decision-making in clinical practice.

Osteopetrosis in a Patient of Systemic Sclerosis Sine Scleroderma: A Rare Association

Systemic sclerosis is a connective tissue disorder of unknown etiology. Although it is a multisystemic disorder, skin thickening is considered as a hallmark of the disease. It usually involves the lungs, gastrointestinal, and musculoskeletal systems. However, a rare subset of systemic sclerosis, systemic sclerosis sine scleroderma, is characterized by internal organ involvement and positive serologic markers with the total or partial absence of cutaneous manifestations. We present a rare association of osteopetrosis in a case of systemic sclerosis sine scleroderma, in a 22-year-old male patient, who presented with pulmonary symptoms as his chief complaints, unreported so far in literature.

Potential Biomarkers in Systemic Sclerosis: A Literature Review and Update

Systemic sclerosis (SSc) is a chronic autoimmune disease characterized by dysregulation of the immune system, vascular damage, and fibrosis of the skin and internal organs. Patients with SSc show a heterogeneous phenotype and a range of clinical courses. Therefore, biomarkers that are helpful for precise diagnosis, prediction of clinical course, and evaluation of the therapeutic responsiveness of disease are required in clinical practice. SSc-specific autoantibodies are currently used for diagnosis and prediction of clinical features, as other biomarkers have not yet been fully vetted. Krebs von den Lungen-6 (KL-6), surfactant protein-D (SP-D), and CCL18 have been considered as serum biomarkers of SSc-related interstitial lung disease. Moreover, levels of circulating brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) can provide diagnostic information and indicate the severity of pulmonary arterial hypertension. Assessment of several serum/plasma cytokines, chemokines, growth factors, adhesion molecules, and other molecules may also reflect the activity or progression of fibrosis and vascular involvement in affected organs. Recently, microRNAs have also been implicated as possible circulating indicators of SSc. In this review, we focus on several potential SSc biomarkers and discuss their clinical utility.

STRATUS: A Phase II Study of Abituzumab in Patients With Systemic Sclerosis-associated Interstitial Lung Disease

OBJECTIVE

To investigate the effects of abituzumab in systemic sclerosis-associated interstitial lung disease (SSc-ILD).

METHODS

STRATUS was a phase II, double-blind, parallel-group, multicenter trial (ClinicalTrials.gov: NCT02745145). Adults (≤ 75 yrs) with SSc-ILD on stable mycophenolate were randomized (2:2:1) to receive intravenous abituzumab 1500 mg, abituzumab 500 mg, or placebo every 4 weeks for 104 weeks. The primary endpoint was the annual rate of change in absolute forced vital capacity.

RESULTS

STRATUS was terminated prematurely due to slow enrollment (n = 75 screened, n = 24 randomized), precluding robust analysis of efficacy. Abituzumab was well tolerated; no new safety signals were detected.

CONCLUSION

Further investigation of abituzumab for treatment of SSc-ILD is required.

Etiology, Risk Factors, and Biomarkers in Systemic Sclerosis with Interstitial Lung Disease

Systemic sclerosis (SSc) is a complex, multiorgan, autoimmune disease. Lung fibrosis occurs in ∼80% of patients with SSc; 25% to 30% develop progressive interstitial lung disease (ILD). The pathogenesis of fibrosis in SSc-associated ILD (SSc-ILD) involves cellular injury, activation/differentiation of mesenchymal cells, and morphological/biological changes in epithelial/endothelial cells. Risk factors for progressive SSc-ILD include older age, male sex, degree of lung involvement on baseline high-resolution computed tomography imaging, reduced Dl_CO, and reduced FVC. SSc-ILD does not share the genetic risk architecture observed in idiopathic pulmonary fibrosis (IPF), with key risk factors yet to be identified. Presence of anti-Scl-70 antibodies and absence of anti-centromere antibodies indicate increased likelihood of progressive ILD. Elevated levels of serum Krebs von den Lungen-6 and C-reactive protein are both associated with SSc-ILD severity and predict SSc-ILD progression. A promising prognostic indicator is serum chemokine (C-C motif) ligand 18. SSc-ILD shares similarities with IPF, although clear differences exist. Histologically, a nonspecific interstitial pneumonia pattern is commonly observed in SSc-ILD, whereas IPF is defined by usual interstitial pneumonia. The course of SSc-ILD is variable, ranging from minor, stable disease to a progressive course, whereas all patients with IPF experience progression of disease. Although appropriately treated patients with SSc-ILD have better chances of stabilization and survival, a relentlessly progressive course, akin to IPF, is seen in a minority. Better understanding of cellular and molecular pathogenesis, genetic risk, and distinctive features of SSc-ILD and identification of robust prognostic biomarkers are needed for optimal disease management.

Patient and Physician Perspectives on Systemic Sclerosis-Associated Interstitial Lung Disease

Systemic sclerosis-associated interstitial lung disease is challenging to diagnose and treat. Patients and physicians can perceive the disease differently and have different views on its management. Communication issues between them can lead to suboptimal disease management. Despite a clear need for improvement in the speed and accuracy of the diagnostic workup, the heterogeneity of clinical symptoms renders the process long and challenging. When considering treatment options, physicians may be more focused on the evidence supporting a particular treatment or on a patient's pulmonary function test results, as opposed to the realities of the patient's difficulties with symptoms or the psychosocial effects of systemic sclerosis-associated interstitial lung disease. Disease management plans should be determined by the patient's own preferences and goals as well as the objective clinical situation. Health care providers must consider their patients as partners on a journey in which treatment decisions are reached jointly. This review will focus on the perspectives of physicians and patients in relation to the diagnosis and management of systemic sclerosis-associated interstitial lung disease. Similarities and differences in these perspectives will be identified, and strategies for achieving optimal disease management will be proposed.

The identification and management of interstitial lung disease in systemic sclerosis: evidence-based European consensus statements

BACKGROUND

Systemic sclerosis-associated interstitial lung disease (ILD) carries a high mortality risk; expert guidance is required to aid early recognition and treatment. We aimed to develop the first expert consensus and define an algorithm for the identification and management of the condition through application of well established methods.

METHODS

Evidence-based consensus statements for systemic sclerosis-associated ILD management were established for six domains (ie, risk factors, screening, diagnosis and severity assessment, treatment initiation and options, disease progression, and treatment escalation) using a modified Delphi process based on a systematic literature analysis. A panel of 27 Europe-based pulmonologists, rheumatologists, and internists with expertise in systemic sclerosis-associated ILD participated in three rounds of online surveys, a face-to-face discussion, and a WebEx meeting, followed by two supplemental Delphi rounds, to establish consensus and define a management algorithm. Consensus was considered achieved if at least 80% of panellists indicated agreement or disagreement.

FINDINGS

Between July 1, 2018, and Aug 27, 2019, consensus agreement was reached for 52 primary statements and six supplemental statements across six domains of management, and an algorithm was defined for clinical practice use. The agreed statements most important for clinical use included: all patients with systemic sclerosis should be screened for systemic sclerosis-associated ILD using high-resolution CT; high-resolution CT is the primary tool for diagnosing ILD in systemic sclerosis; pulmonary function tests support screening and diagnosis; systemic sclerosis-associated ILD severity should be measured with more than one indicator; it is appropriate to treat all severe cases; no pharmacological treatment is an option for some patients; follow-up assessments enable identification of disease progression; progression pace, alongside disease severity, drives decisions to escalate treatment.

INTERPRETATION

Through a robust modified Delphi process developed by a diverse panel of experts, the first evidence-based consensus statements were established on guidance for the identification and medical management of systemic sclerosis-associated ILD.

FUNDING

An unrestricted grant from Boehringer Ingelheim International.

Lung function is associated with minimal EQ-5D changes over time in patients with systemic sclerosis

In systemic sclerosis (SSc) therapeutic efforts are often directed to prevent progressive respiratory impairment, but it is unclear to what extent changes in pulmonary function tests (PFTs) are associated with health-related quality of life (HRQoL). The aim of our study is to evaluate how modifications in PFTs contribute to longitudinal variations in HRQoL, assessed through the multidimensional questionnaire EQ-5D, in patients with SSc. We included SSc patients with forced vital capacity (FVC%), diffusing capacity of the lungs for carbon monoxide (DLCO%) and EQ-5D assessed in at least two visits. The EQ-5D consists of two parts, a utility score ranging from − 0.59 to 1, and a 0–100 Visual Analogue Scale (VAS). Higher values represent better health. The association between changes in FVC% and DLCO%, and evolution of EQ-5D over time, was investigated using generalized estimating equations. Three hundred seventy-eight patients were included, accounting for a total of 1619 measurements. The models showed that improvement in FVC% is significantly associated with increase in both utility score (β = 0.001; 95% CI 0.000 to 0.002; p = 0.003) and VAS over time (β = 0.188; 95% CI 0.111 to 0.264; p < 0.001). Moreover, improvement in DLCO% is longitudinally associated with increase in utility score (β = 0.001; 95% CI 0.000 to 0.002; p = 0.038), while the results for VAS were non-significant (β = 0.020; 95% CI -0.079 to 0.120; p = 0.690). We show that change in PFTs has a significant, although minor, impact on HRQoL as measured by EQ-5D in SSc.Key Points• In patients with SSc, changes in PFTs have a significant, although minor, impact on HRQoL.• In patients with SSc-ILD, the perception of HRQoL is nearly not influenced by changes in pulmonary function.• The use of generic questionnaires might not be sensitive enough to evaluate the impact on quality of life of therapies targeting specific SSc manifestations.

Interstitial Lung Disease in Systemic Sclerosis: Focus on Early Detection and Intervention

Systemic sclerosis (SSc) is a progressive and often devastating disease characterized by autoimmune dysfunction, vasculopathy, and fibrosis. Interstitial lung disease (ILD) is identified in the majority of patients with SSc and is the leading cause of SSc-related mortality. Although clinical manifestations and ILD severity vary among patients, lung function typically declines to the greatest extent during the first 3-4 years after disease onset. We aim to provide an overview of SSc-associated ILD (SSc-ILD) with a focus on current and emerging tools for early diagnosis of ILD and current and novel treatments under investigation. Early detection of ILD provides the opportunity for early therapeutic intervention, which could improve patient outcomes. Thoracic high-resolution computed tomography is the most effective method of identifying ILD in patients with SSc; it enables detection of mild lung abnormalities and plays an important role in monitoring disease progression. Cyclophosphamide and mycophenolate mofetil are the most commonly prescribed treatments for SSc-ILD. Recently, nintedanib (an antifibrotic) was approved by the Food and Drug Administration for patients with SSc-ILD; it is indicated for slowing the rate of decline in pulmonary function. However, there is a need for additional effective and well-tolerated disease-modifying therapy. Ongoing studies are evaluating other antifibrotics and novel agents. We envision that early detection of lung involvement, combined with the emergence and integration of novel therapies, will lead to improved outcomes in patients with SSc-ILD.

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.

[Treatment of systemic sclerosis-associated interstitial lung disease]

BACKGROUND

Systemic sclerosis (SSc) is a fibrosing autoimmune disease of the connective tissue. In addition to skin fibrosis, pulmonary involvement and interstitial lung disease (ILD) in particular are the most common and severe manifestations of SSc. The disease is associated with a substantial risk of morbidity and mortality, especially in progressive ILD. In the last 5 years new treatment concepts for SSc-ILD have been investigated in numerous clinical studies.

MATERIAL AND METHODS

This review is based on a literature search in PubMed, focusing on the most relevant papers published up to the end of 2018 with the keywords "SSc" and "treatment".

RESULTS

The treatment of SSc-ILD has changed over the last few years due to the results of many clinical studies. The updated guidelines of the European League Against Rheumatism (EULAR) recommend the use of cyclophosphamide or hematopoietic stem cell transplantation. Data for a positive influence on SSc-ILD are also available for mycophenolate, tocilizumab and anabasum. Because of the pathophysiological similarities to idiopathic pulmonary fibrosis, the use of the antifibrotic agents nintedanib and pirfenidone is currently being investigated in randomized, multicenter clinical trials and could be a novel and promising therapeutic strategy.

CONCLUSION

Current drug studies may provide innovative therapeutic perspectives for SSc-ILD and could significantly improve the prognosis of affected patients in the future.

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 &lt;10%, moderate 10–30%, severe &gt;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&lt;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&lt;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&lt;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&lt;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&lt;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.

Detection and classification of systemic sclerosis-related interstitial lung disease: a review

PURPOSE OF REVIEW

Systemic sclerosis (SSc) is a heterogeneous disease with a variable disease course. Interstitial lung disease (ILD) is one of the leading causes of morbidity and mortality in patients with SSc. The present review highlights recent advances in the classification, diagnosis, and early detection of SSc-associated ILD (SSc-ILD).

RECENT FINDINGS

Risk stratification through measurement of disease extent on high-resolution computed tomography (HRCT) of the chest, longitudinal declines in pulmonary function tests (PFTs), and mortality prediction models have formed the basis for classifying clinically significant ILD. HRCT may be preferred over PFTs for screening, as PFTs lack sensitivity and have a high false-negative rate. Novel imaging modalities and biomarkers hold promise as adjunct methods for assessing the presence and severity of SSc-ILD, and predicting risk for progressive disease. Further validation is required prior to their use in clinical settings.

SUMMARY

Classification of SSc-ILD has shifted to a personalized approach that considers an individual patient's probability of progressive disease through identification of risk factors, measurement of disease extent on HRCT, longitudinal declines in PFTs, and mortality prediction models. There remains an unmet need to develop screening guidelines for SSc-ILD.