Management of Systemic Sclerosis-Related Skin Disease: A Review of Existing and Experimental Therapeutic Approaches

The validity and reliability of the Swedish version of the Satisfaction with appearance scale for individuals with systemic sclerosis

Background

Systemic sclerosis (SSc) can lead to visible changes in appearance which could generate concerns among patients. Thus, valid questionnaires that capture these concerns are valuable to identify and communicate appearance concerns.

Objective

To determine aspects of the validity and reliability of the Swedish version of the Satisfaction with Appearance scale for individuals with SSc (SWAP-Swe in SSc).

Methods

Content validity was assessed by interviews. In a cross-sectional design, construct validity was evaluated by comparing the self-reported questionnaire SWAP-Swe in SSc to the Scleroderma Health Assessment Questionnaire (SSc HAQ), Patient Health Questionnaire-8 (PHQ-8), RAND-36, modified Rodnan skin score (mRSS), disease duration and age using Spearman's rank correlations (r_s ). Internal consistency was evaluated by Cronbach's alpha coefficient and corrected item-to-total correlations. Test-retest reliability was investigated using the intraclass correlation coefficient (ICC).

Results

Eleven patients and 10 health professionals participated in the assessment of content validity. For the other aspects of validity and reliability 134 patients (median age 62 years, women 81%, limited cutaneous SSc 75%) participated. Overall, the content validity was satisfactory. The SWAP-Swe in SSc correlated with SSc HAQ (HAQ-DI r_s  = 0.50, visual analogue scales r_s  = 0.24-0.41), PHQ-8 (r_s  = 0.46), RAND-36 (r_s  = -0.21 to -0.47), mRSS (r_s  = 0.28), disease duration (r_s  = -0.01) and age (r_s  = -0.15). The Cronbach's alpha coefficient was 0.92, corrected item-to-total correlations ⩾ 0.45 and the ICC 0.82.

Conclusion

The SWAP-Swe in SSc showed satisfactory content validity, sufficient and good internal consistency and sufficient test-retest reliability. It was more strongly associated with self-reported questionnaires than with physician-assessed skin involvement and age, indicating that appearance concerns in SSc seem to be multidimensional as earlier reported. Our study contributes with a thorough investigation of validity and reliability including aspects that have not been investigated before. However, evaluation of more validity aspects of the SWAP-Swe in SSc is suggested.

Epidemiology and Treatment of Systemic Sclerosis in Korea

Systemic sclerosis (SSc), a rare, chronic progressive systemic autoimmune disease of unknown etiology, is characterized by autoimmunity, tissue fibrosis, and obliterative vasculopathy. SSc can affect all major organs including the skin, blood vessels, lung, heart, kidneys, and gastrointestinal tract. Our understanding of its pathogenesis has increased over the past few decades, leading to improved diagnosis and treatment. However, the mortality rate of SSc remains considerable, mainly due to cardiopulmonary causes. A growing body of evidence suggests that geographical, regional, and ethnic differences could affect the epidemiology, clinical characteristics and prognosis of SSc. Although Korean data of this issue are lacking, a considerable amount of research has been published by many Korean researchers. To establish treatment strategies for Korean patients, extensive Korean research data are needed. This review summarizes the prevalence, incidence, mortality, and clinical and laboratory manifestations of Korean patients with SSc and discusses the current trends in evidence-based treatment and recommendations.

Predicting the Progression of Very Early Systemic Sclerosis: Current Insights

Systemic sclerosis (SSc) is a complex autoimmune connective tissue disease with distinct pathological hallmarks (ie, inflammation, vasculopathy, fibrosis) that may predominate at different stages in the disease course with varying severity. Initial efforts to classify patients with SSc identified a subset of patients with very early SSc. These patients possessed signs of SSc (eg, Raynaud phenomenon, SSc specific autoantibodies and/or nailfold capillary abnormalities) without fulfilling complete SSc classification criteria. Recognizing the inherent value in early diagnosis and intervention in SSc, researchers have endeavored to identify risk factors for progression from very early SSc to definite SSc. The present review summarizes the clinical phenotype of patients with very early and early SSc. Through a scoping review of recent literature, this review also describes risk factors for progression to definite SSc with a focus on the specific clinical features that arise early in the SSc disease course (eg, diffuse cutaneous sclerosis, interstitial lung disease, esophageal dysfunction, renal crisis, cardiac involvement). In addition to clinical risk factors, this review provides evidence for how biological data (ie, serological, genomic, proteomic profiles, skin bioengineering methods) can be integrated into risk assessment models in the future. Furthering our understanding of biological features of very early SSc will undoubtedly provide novel insights into SSc pathogenesis and may illuminate new therapeutic targets to prevent progression of SSc.

An update on the pharmacotherapeutic options and treatment strategies for systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is a multi-dimensional connective tissue disease of unknown etiology. Given the immense clinical complexity of SSc, the treatment of this condition is not standardized and considerable heterogeneity exists in SSc management approaches. The purpose of this article is to highlight novel therapeutic strategies and new medications under development for the treatment of systemic sclerosis (SSc).

AREAS COVERED

Herein, the authors focus primarily on recently completed clinical trials and phase 3 and 4 clinical trials of therapeutic agents that show promise in SSc. This review is organized by the clinical complications that occur in SSc, for which novel treatment strategies are under study.

EXPERT OPINION

Combining therapies to address the individual manifestations of SSc is a cornerstone to the comprehensive management of this condition. Therapeutic strategies must take into account the organs involved, the level of disease activity in each area, and the disease stage. Controlling the complex biological network, progressive vasculopathy and fibrosis, as well as manifestations of end-organ dysfunction are all critical considerations when determining the best treatment approach for SSc.

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.

Biologics in Microangiopathic Wounds

In the last decades the possibility to diagnose a skin ulcer has greatly improved. We learnt that a consistent percentage of nonhealing ulcers may be caused by a microangiopathic disorder that has not been properly investigated and cured. Pathogenetically, we can distinguish 2 main groups: (1) ulcers due to inflammatory microangiopathy, mainly including cutaneous small and medium vessel vasculitis, pyoderma gangrenosum, and connective tissue diseases, and (2) ulcers due to occlusive microangiopathy. The group of microangiopathic occlusive ulcers is more heterogeneous and includes different disorders ranging from livedo vasculopathy to calciphylaxis, hydroxyurea-induced ulcers, antiphospholipid antibodies ulcers, and various other types. These conditions can induce thromboses or anatomo-functional occlusion of cutaneous microvessels. Despite different physiopathologic mechanisms, the ulcer resulting from a primitive microangiopathy may receive basic treatments that are in the complex similar to other pathogenetically different wounds, including MOIST-based local therapy and elastic compression when it is not contraindicated. Persistent inflammatory processes are increasingly demonstrated as responsible for the chronicity of many skin ulcers. New data concerning the biological phases of wound healing and the molecules that play crucial roles in this process suggested the use of new specific therapies. Some of them such as growth factors and platelet-rich plasma are prevalently used as topical biologic agents with variable benefits. In recent years, a new class of systemic anti-inflammatory molecules, better known as biologic drugs, have been introduced in the cure of chronic inflammatory diseases that can induce microangiopathic injuries and ulcerative complication. They enlarged the therapeutic options in case of nonresponder microangiopathic ulcers and could represent a future model of “pathogenetically based” therapy of skin ulcers.

Assessment of skin involvement in systemic sclerosis

Skin involvement in SSc is an important marker of disease activity, severity and prognosis, making the assessment of skin a key issue in SSc clinical research. We reviewed the published data assessing skin involvement in clinical trials and summarized the major conclusions important in SSc clinical research. A systematic literature review identified randomized controlled trials using skin outcomes in SSc. Analysis examined the validity of the different skin measures based on literature findings. Twenty-two randomized controlled trials were found. The average study duration was 10.2 (s.d. 4.5) months, mean (s.d.) sample size 32.4 (32.6) and 26.7 (27.8) in intervention and control arms, respectively. The 17-site modified Rodnan skin score is a fully validated primary outcome measure in diffuse cutaneous SSc. Skin histology seems to be an appropriate method for evaluation of skin thickness. These findings have important implications for clinical trial design targeting skin involvement in SSc.

Use of intravenous epoprostenol as a treatment for the digital vasculopathy associated with the scleroderma spectrum of diseases

Introduction

Intravenous prostanoid therapy is recommended for severe systemic sclerosis-related digital vasculopathy. The evidence supporting this recommendation is limited. The aim of this study was to evaluate the safety and efficacy of treating scleroderma spectrum digital vasculopathy with intravenous epoprostenol.

Methods

Patients with a diagnosis of systemic sclerosis who had received intravenous epoprostenol for scleroderma spectrum digital vasculopathy between 1st October 2003 and 1st September 2015 at Boston University Medical Center were identified using ICD-9 code search, and their charts were reviewed in this retrospective case series.

Results

Of 47 encounters for intravenous epoprostenol infusion for scleroderma spectrum digital vasculopathy, 29 had documentation of improvement as indicated by any of the following: pain relief, increased perfusion of digits as assessed by warmth or color, reduced digital ulcer number or size. In 16 encounters, there was no documentation on whether the indicative condition had improved. No deterioration of the indicative condition was documented in any encounters. Intravenous epoprostenol infusion was well tolerated with few significant adverse effects.

Conclusions

Intravenous epoprostenol infusion in the treatment of scleroderma spectrum digital vasculopathy is safe. The condition improved with intravenous epoprostenol infusion, although there were study design constraints. We describe our protocol for administering intravenous epoprostenol infusion for scleroderma spectrum digital vasculopathy to improve consistency of patient care.

Scleroderma-related interstitial lung disease

Scleroderma-related interstitial lung disease (SSc-ILD) is a pulmonary fibrosing disorder characterized by systemic inflammation and progressive scarring of the lungs that leads to respiratory failure. Although certain immunosuppressive therapies may slow disease progression, current treatment strategies are not curative; consequently, SSc-ILD continues to be a major cause of morbidity and mortality. We present four cases of SSc-ILD that emphasize the importance of early screening and detection, close follow-up, and aggressive management. We also highlight the need for well-conducted clinical trials designed to identify new and effective treatments.

Development and validation of a patient-reported outcome instrument for skin involvement in patients with systemic sclerosis

OBJECTIVES

We developed a patient-reported outcome (PRO) instrument to assess the skin-related quality of life in patients with systemic sclerosis (SSc).

METHODS

Participants with SSc provided input on skin-related health effects through focus groups. We developed items for scleroderma skin PRO (SSPRO) to encompass these effects. Further consideration from cognitive interviews and an expert panel led to reduction and modification of items. A 22-item SSPRO was field tested. Psychometric analysis included test-retest reliability, internal consistency and exploratory factor analysis (EFA). Construct validity was assessed through correlation with other participant and physician-assessed measures.

RESULTS

140 participants completed the SSPRO: mean age was 53.4 years, median disease duration was 5 years, 82.1% were female and 32.9% had diffuse cutaneous SSc. EFA supported four factors in SSPRO corresponding to hypothesised constructs: physical effects, physical limitations, emotional effects and social effects. Removal of 4/22 items resulted in acceptable goodness-of-fit statistics. Test-retest reliability (intraclass correlation coefficient=0.61-0.83) was moderate to high and internal consistency (Cronbach's α=0.89-0.96) was high. SSPRO correlated strongly with other participant-reported measures (r=0.59-0.88) suggesting construct validity, and less well with physician-assessed measures (r=0.31-0.40). SSPRO scores were significantly different for each level of participant-reported skin severity, and for limited versus diffuse cutaneous SSc.

CONCLUSIONS

SSPRO has been developed with extensive patient input and demonstrates evidence for reliability and validity. It is complementary to existing measures of SSc skin involvement with emphasis on the patient's experience. Further research is needed to assess its sensitivity to change.

Stretching Reduces Skin Thickness and Improves Subcutaneous Tissue Mobility in a Murine Model of Systemic Sclerosis

Objective

Although physical therapy can help preserve mobility in patients with systemic sclerosis (SSc), stretching has not been used systematically as a treatment to prevent or reverse the disease process. We previously showed in rodent models that stretching promotes the resolution of connective tissue inflammation and reduces new collagen formation after injury. Here, we tested the hypothesis that stretching would impact scleroderma development using a mouse sclerodermatous graft-versus-host disease (sclGvHD) model.

Methods

The model consists in the adoptive transfer (allogeneic) of splenocytes from B10.D2 mice (graft) into Rag2^−/− BALB/c hosts (sclGvHD), resulting in skin inflammation followed by fibrosis over 4 weeks. SclGvHD mice and controls were randomized to stretching in vivo for 10 min daily versus no stretching.

Results

Weekly ultrasound measurements of skin thickness and subcutaneous tissue mobility in the back (relative tissue displacement during passive trunk motion) successfully captured the different phases of the sclGvHD model. Stretching reduced skin thickness and increased subcutaneous tissue mobility compared to no stretching at week 3. Stretching also reduced the expression of CCL2 and ADAM8 in the skin at week 4, which are two genes known to be upregulated in both murine sclGvHD and the inflammatory subset of human SSc. However, there was no evidence that stretching attenuated inflammation at week 2.

Conclusion

Daily stretching for 10 min can improve skin thickness and mobility in the absence of any other treatment in the sclGvHD murine model. These pre-clinical results suggest that a systematic investigation of stretching as a therapeutic modality is warranted in patients with SSc.

Integrated, multicohort analysis of systemic sclerosis identifies robust transcriptional signature of disease severity

Systemic sclerosis (SSc) is a rare autoimmune disease with the highest case-fatality rate of all connective tissue diseases. Current efforts to determine patient response to a given treatment using the modified Rodnan skin score (mRSS) are complicated by interclinician variability, confounding, and the time required between sequential mRSS measurements to observe meaningful change. There is an unmet critical need for an objective metric of SSc disease severity. Here, we performed an integrated, multicohort analysis of SSc transcriptome data across 7 datasets from 6 centers composed of 515 samples. Using 158 skin samples from SSc patients and healthy controls recruited at 2 centers as a discovery cohort, we identified a 415-gene expression signature specific for SSc, and validated its ability to distinguish SSc patients from healthy controls in an additional 357 skin samples from 5 independent cohorts. Next, we defined the SSc skin severity score (4S). In every SSc cohort of skin biopsy samples analyzed in our study, 4S correlated significantly with mRSS, allowing objective quantification of SSc disease severity. Using transcriptome data from the largest longitudinal trial of SSc patients to date, we showed that 4S allowed us to objectively monitor individual SSc patients over time, as (a) the change in 4S of a patient is significantly correlated with change in the mRSS, and (b) the change in 4S at 12 months of treatment could predict the change in mRSS at 24 months. Our results suggest that 4S could be used to distinguish treatment responders from nonresponders prior to mRSS change. Our results demonstrate the potential clinical utility of a novel robust molecular signature and a computational approach to SSc disease severity quantification.

Emerging drugs and therapeutics for systemic sclerosis

INTRODUCTION

Treatment of systemic sclerosis (SSc) is challenging despite advances in medical therapeutics for other rheumatologic diseases. Significant disease modifying therapy is lacking for most patients with SSc, due to the heterogeneous multisystem nature of SSc and its complex pathophysiology. The emergence of organ based management strategies has provided guidance in patient care as well as research and drug development. Areas covered: Design and development of new compounds focused on the underlying fibrotic disease processes have been sparse. Therefore, organ based strategies with targeted approaches have been directed towards the most devastating and life threatening features of systemic sclerosis. These include pulmonary arterial hypertension, interstitial lung disease, peripheral vasculopathy and skin thickening. In this context, new treatment regimens using older drugs as well as discovery of novel compounds based on recent insights of the disease pathophysiology are discussed. Expert opinion: Systemic sclerosis is a heterogeneous rare disease that carries a high burden of morbidity and mortality. Organ based management strategies have improved the natural history of systemic sclerosis using targeted interventions or strategies, particularly vascular features. However, more research is required to better understand disease mechanisms, including an ultimate unifying pathway that explains the multisystem nature of systemic sclerosis.

Treatment of Rapidly Progressive Systemic Sclerosis: Current and Futures Perspectives

INTRODUCTION

Systemic Sclerosis (SSc) is a systemic autoimmune disease characterized by severe and often progressive cutaneous, pulmonary, cardiac and gastrointestinal tract fibrosis, cellular and humoral immunologic alterations, and pronounced fibroproliferative vasculopathy. There is no effective SSc disease modifying therapy. Patients with rapidly progressive SSc have poor prognosis with frequent disability and very high mortality.

AREAS COVERED

This paper reviews currently available therapeutic approaches for rapidly progressive SSc and discuss novel drugs under study for SSc disease modification.

EXPERT OPINION

The extent, severity, and rate of progression of SSc skin and internal organ involvement determines the optimal therapeutic interventions for SSc. Cyclophosphamide for progressive SSc-associated interstitial lung disease and mycophenolate for rapidly progressive cutaneous involvement have shown effectiveness. Methotrexate has been used for less severe skin progression and for patients unable to tolerate mycophenolate. Rituximab was shown to induce improvement in SSc-cutaneous and lung involvement. Autologous bone marrow transplantation is reserved for selected cases in whom poor survival risk outweighs the high mortality rate of the procedure. Novel agents capable of modulating fibrotic and inflammatory pathways involved in SSc pathogenesis, including tocilizumab, pirfenidone, tyrosine kinase inhibitors, lipid lysophosphatidic acid 1, and NOX4 inhibitors are currently under development for the treatment of rapidly progressive SSc.