Is there today a place for corticosteroids in the treatment of scleroderma?

Clinical characteristics of systemic sclerosis patients with occupational silicosis

To explore the clinical characteristics of systemic sclerosis complicated with silicosis. The systemic sclerosis patients treated in the Guangxi Workers' Hospital and the People's Hospital of Guangxi Zhuang Autonomous Region from January 2000 to December 2020 were divided into the systemic sclerosis with silicosis group and the systemic sclerosis without silicosis group. Survival analysis was performed using Kaplan-Meier estimates the Cox proportional hazards model. A propensity score matching was applied in order to avoid the selection bias.Over the past 20 years, 72 systemic sclerosis patients with silicosis and 238 systemic sclerosis patients without silicosis were treated in the two hospitals. The systemic sclerosis patients with silicosis group had more males (P < 0.000),lower mean age at onset of SSc (P < 0.000), more frequent occurrence of weight loss (P = 0.028), smoking (P < 0.000), tuberculosis (P < 0.000), cardiac involvement (P < 0.000), ILD (P = 0.017), pulmonary hypertension (P = 0.024), elevated BNP (P < 0.000). With regards to the multivariate Cox regression analysis, silicosis was related with a higher overall mortality before (HR = 3.666, 95% CI = 1.440-11.234, p = 0.025) and after the propensity score matching analysis (HR = 2.817, 95% CI = 1.196-10.764, p = 0.014). Independent risk factors for overall mortality were Gangrene (HR = 3.003, 95% CI = 1.343-9.431), Cardiac involved (HR = 5.370, 95% CI = 1.910-15.472), Scl-70 (HR = 3.569, 95% CI = 1.333-10.869), Elevated BNP (HR = 2.135, 95% CI = 1.293-9.564).Concomitant silicosis worsens systemic sclerosis patients' prognoses. Gangrene, Scl-70, elevated BNP and cardiac involvement are independent risk factors for overall mortality. Key Points •Concomitant silicosis worsens SSc patients' prognoses. •For individuals with occupational exposure, close observation of the symptoms of SSc, early diagnosis, and interruption of exposure may improve the prognosis. •Gangrene, Scl-70, elevated BNP and cardiac involvement are independent risk factors for overall mortality.

A Phase II randomized controlled trial of oral prednisolone in early diffuse cutaneous systemic sclerosis (PRedSS)

OBJECTIVES

Although the painful and disabling features of early diffuse cutaneous SSc (dcSSc) have an inflammatory basis and could respond to corticosteroids, corticosteroids are a risk factor for scleroderma renal crisis. Whether or not they should be prescribed is therefore highly contentious. Our aim was to examine safety and efficacy of moderate-dose prednisolone in early dcSSc.

METHODS

PRedSS set out as a Phase II, multicentre, double-blind randomized controlled trial, converted to open-label during the Covid-19 pandemic. Patients were randomized to receive either prednisolone (∼0.3 mg/kg) or matching placebo (or no treatment during open-label) for 6 months. Co-primary endpoints were the HAQ Disability Index (HAQ-DI) and modified Rodnan skin score (mRSS) at 3 months. Over 20 secondary endpoints included patient reported outcome measures reflecting pain, itch, fatigue, anxiety and depression, and helplessness. Target recruitment was 72 patients.

RESULTS

Thirty-five patients were randomized (17 prednisolone, 18 placebo/control). The adjusted mean difference between treatment groups at 3 months in HAQ-DI score was -0.10 (97.5% CI: -0.29, 0.10), P = 0.254, and in mRSS -3.90 (97.5% CI: -8.83, 1.03), P = 0.070, both favouring prednisolone but not significantly. Patients in the prednisolone group experienced significantly less pain (P = 0.027), anxiety (P = 0.018) and helplessness (P = 0.040) than control patients at 3 months. There were no renal crises, but sample size was small.

CONCLUSION

PRedSS was terminated early primarily due to the Covid-19 pandemic, and so was underpowered. Therefore, interpretation must be cautious and results considered inconclusive, indicating the need for a further randomized trial.

TRIAL REGISTRATION

ClinicalTrials.gov, https://clinicaltrials.gov, NCT03708718.

Symptomatic fractures in systemic sclerosis: A case-control study

This case-control study analyzed risk factors for symptomatic fractures in a group of 52 patients with systemic sclerosis compared with a group of 104 patients without fractures, matched for sex and age, who were attended at a single systemic sclerosis outpatient clinic from 2010 to 2020. Fractures affected predominantly vertebral (65.4%), rib (13.5%), and hip (7.7%) joints, while the mean age of fracture was 55.3 ± 9.5 years. Age at disease onset, age at diagnosis, disease duration, age at menarche, and age at menopause were similar in both groups, and 58.9% of the patients were menopausal at the time of the fracture. The presence of fractures had a significant association with densitometric osteoporosis (p < 0.001), lower weight (p = 0.032), and bone mineral index (p = 0.044), anti-RNA polymerase III (p = 0.040), use of corticosteroids (p = 0.019), and bisphosphonates (p < 0.001), as well as with densitometric T-scores of lumbar spine (p < 0.001), femoral neck (p = 0.025), and total hip (p = 0.013). Multivariate analysis showed that the variables significantly associated with fractures were high doses of corticosteroids (odds ratio = 4.10; 95% confidence interval = 1.290-13.090; p = 0.017), bisphosphonates (odds ratio = 3.91; 95% confidence interval = 1.699-8.984; p = 0.001), negative anti-Scl70 (OR = 0.34; 95% confidence interval = 0.124-0.943; p = 0.038), and lumbar T-score (odds ratio = 0.39; 95% confidence interval = 0.034-0.460; p = 0.010). In conclusion, symptomatic fractures were associated predominantly with lower bone mineral density of lumbar spine and use of high doses of corticosteroids and bisphosphonates in this cohort.

Autoimmunity in 2019

Based on the PubMed data, we have been performing a yearly evaluation of the publications related to autoimmune diseases and immunology to ascertain the relative weight of the former in the scientific literature. It is particularly intriguing to observe that despite the numerous new avenues of immune-related mechanisms, such as cancer immunotherapy, the proportion of immunology manuscripts related to autoimmunity continues to increase and has been approaching 20% in 2019. As in the previous 13 years, we performed an arbitrary selection of the peer-reviewed articles published by the major dedicated Journals and discussed the common themes which continue to outnumber peculiarites in autoimmune diseases. The investigated areas included systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), psoriatic arthritis (PsA), autoantibodies (autoAbs), and common therapeutic avenues and novel pathogenic mechanisms for autoimmune conditions. Some examples include new pathogenetic evidence which is well represented by IL21 or P2X7 receptor (P2X7R) in SLE or the application of single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq), and flow cytometry for the analysis of different cellular populations in RA. Cumulatively and of interest to the clinicians, a large number of findings continue to underline the importance of a strict relationship between basic and clinical science to define new pathogenetic and therapeutic developments. The therapeutic pipeline in autoimmunity continues to grow and maintain a constant flow of new molecules, as well illustrated in RA and PsA, and this is most certainly derived from the new basic evidence and the high-throughput tools applied to autoimmune diseases.

Effect of short-interval rituximab and high-dose corticosteroids on kidney function in systemic sclerosis: Long-term experience of a single centre

INTRODUCTION

Scleroderma renal crisis (SRC) is a rare but one of the most recognised complications of systemic sclerosis (SSc). Corticosteroid (CS) use has been considered as a major risk factor for SRC. Several studies reported the efficacy of rituximab (RTX) with an acceptable safety profile in SSc. However, data on the long-term effect of high-dose CS concomitant to RTX on kidney function are lacking.

METHODS

We retrospectively analysed SSc patients (n = 35) treated with a lower dosage and short-interval RTX and concomitant high-dose CS at the Department of Internal Medicine at the Medical University of Graz between 2010 and 2019. The kidney function was assessed using the estimated glomerular filtration rate (eGFR) at every RTX admission. The annual decline of kidney function was evaluated by linear mixed model analysis.

RESULTS

At the RTX initiation, one patient had a decreased kidney function indicated by eGFR < 60 mL/min/1.73 m² (median: 96 mL/min/1.73 m² ; interquartile range (IQR): 43-136). Patients received RTX and complementary high-dose CS for a median follow-up time of 3.4 years (range 0.6-9.5). A linear mixed model analysis with the patient as random effect and time from first RTX as fixed effect estimated an annual decline of 1.98 mL/min/1.73 m² of the eGFR (95% confidence interval: [-2.24, -1.72]; P <.001). During the follow-up period, no patient experienced SRC or a significant drop in kidney function.

CONCLUSIONS

A regular, high-dose CS given contemporary to RTX seems to be a safe option for kidney function in patients with SSc. Our findings provide additional knowledge in risk evaluation and planning of individualised therapies or designing clinical studies using RTX.

Histopathological features of systemic sclerosis-associated myopathy: A scoping review

BACKGROUND

Scleromyositis (SM) is an emerging subset of myositis associated with features of systemic sclerosis (SSc) but it is currently not recognized as a distinct histopathological subset by the European NeuroMuscular Center (ENMC). Our aim was to review studies reporting muscle biopsies from SSc patients with myositis and to identify unique histopathological features of SM.

METHODS

A scoping review was conducted and included all studies reporting histopathological findings in SSc patients with myositis searching the following databases: PubMed, MEDLINE, EMBASE, CINAHL and EBM-Reviews. Clinical, serological, and histopathological data were extracted using a standardized protocol.

RESULTS

Out of 371 citations, 77 studies that included 559 muscle biopsies were extracted. Fifty-seven percent (n = 227/400) had inflammatory infiltrates, predominantly T cells, which were endomysial (49%), perimysial (42%) and perivascular (41%). Few studies (18%, n = 8/44) evaluated the presence of B-cells. Myofiber atrophy was present in 48% (n = 104/218) of biopsies, and was predominantly perifascicular in 19% (n = 6/31), with necrosis reported in 56% (n = 162/290) of cases. Sarcolemmal MHC-I upregulation was found in 72% (n = 64/89) of biopsies. Non-specified C5b-9 deposition was described in 39% of muscle biopsies (n = 28/72). Neurogenic features were present in 23% (n = 44/191); endomysial fibrosis was reported in 35% (n = 120/340); and rimmed vacuoles were observed in 32% (n = 11/34) of biopsies. Capillaropathy, such as capillary dropout and/or ultrastructural endothelial abnormalities, was reported in 33% (n = 43/129) of cases. Reported ENMC categories were mainly polymyositis (21%), non-specific myositis (19%), immune-mediated necrotizing myopathy (16%), and dermatomyositis (8%). Histopathological features were analyzed according to serological subtypes in 28 studies, including anti-PM-Scl (n = 48), -Ku (n = 23) and -U1RNP (n = 90). Most of these biopsies demonstrated inflammatory infiltrates (range 49-85%) as well as MHC-I expression (range 63-81%). Necrosis was associated with anti-Ku (85%) and anti-U1RNP (73%), while anti-Ku was also associated with neurogenic features and rimmed vacuoles in 57% and 25% of cases, respectively.

CONCLUSION

Our review suggests that SM is characterized by heterogeneous pathological features using definitions included in current histopathological criteria. Whether a distinct histopathological signature exists in SM remains to be determined. SSc-specific and SSc-associated autoantibodies may help define more homogeneous histopathological subsets.

Human mesenchymal stem cells for the management of systemic sclerosis. Systematic review

INTRODUCTION

Sistemic Sclerosis (SSc) is a heterogeneous autoimmune disease with a high rate of progression and therapeutic failure, and treatment is a challenge, new therapeutic proposals being needed, being mesenchymal stem cells (MSCs) considered as alternative therapy for SSc for its immunomodulatory capacity. We evaluated the efficacy and safety of human MSC (hMSC) in patients with SSc through a systematic literature review (SLR).

METHODS

SLR (PRISMA guideline) on MEDLINE/OVID, LILACS, EMBASE, and Cochrane/OVID bases (until July 2020, without limits). All types of clinical studies were considered: patients ≥18 years old with SSc and treatment with hMSC.

EXCLUSION CRITERIA

animal models, autologous/allogenic hematopoietic stem cell transplants, narrative reviews, letters to the editor. MeSH and "Key word" terms were used. The level of evidence and the quality rating were rated [Joanna Briggs Institute (JBI) lists]. Registration in PROSPERO repository (ID CRD42020185245) The Synthesis Without Meta-analysis (SWiM) guideline was followed.

RESULTS

We initially identified 508 articles, of which 11 were finally included (8 case series and 3 case reports). The 11 articles included 101 patients (85 female, age range 18-75 years). The level of evidence was mostly 4 (JBI); the quality of evidence was met (≥50% of JBI items). SWiM showed that vascular skin involvement (digital ulcers, necrosis, and gangrene) and associated pain were the predominant outcomes, while improvements were found in almost all cases. One patient died in the first month, and the frequency of complications was low. Expanded hMSCs were used in 24 patients and other cell sources in the remaining patients.

CONCLUSION

There is too little reported data to reach definite conclusions about the use of hMSC in SSc. Further studies with better epidemiological designs are needed to evaluate the benefit of hMSCs in SSc patients.

Epidemiology of systemic sclerosis: a multi-database population-based study in Tuscany (Italy)

Background

Systemic Sclerosis (SSc) is a chronic autoimmune disease with a complex pathogenesis that includes vascular injury, abnormal immune activation, and tissue fibrosis. We provided a complete epidemiological characterization of SSc in the Tuscany region (Italy), considering prevalence and incidence, survival, comorbidities and drug prescriptions, by using a multi-database population-based approach. Cases of SSc diagnosed between 1st January 2003 and 31st December 2017 among residents in Tuscany were collected from the population-based Rare Diseases Registry of Tuscany. All cases were linked to regional health and demographic databases to obtain information about vital statistics, principal causes of hospitalization, complications and comorbidities, and drug prescriptions.

Results

The prevalence of SSc in Tuscany population resulted to be 22.2 per 100,000, with the highest prevalence observed for the cases aged ≥ 65 years (33.2 per 100,000, CI 95% 29.6–37.3). In females, SSc was predominant (86.7% on the total) with an overall sex ratio F/M of 6.5. Nevertheless, males presented a more severe disease, with a lower survival and significant differences in respiratory complications and metabolic comorbidities. Complications and comorbidities such as pulmonary involvement (HR = 1.66, CI 95% 1.17–2.35), congestive heart failure (HR = 2.76, CI 95% 1.80–4.25), subarachnoid and intracerebral haemorrhage (HR = 2.33, CI 95% 1.21–4.48) and malignant neoplasms (HR = 1.63, CI 95% 1.06–2.52), were significantly associated to a lower survival, also after adjustment for age, sex and other SSc-related complications. Disease-modifying antirheumatic drugs, endothelin receptor antagonists, and phosphodiesterase-5 inhibitors were the drugs with the more increasing prevalence of use in the 2008–2017 period.

Conclusions

The multi-database approach is important in the investigation of rare diseases where it is often difficult to provide accurate epidemiological indicators. A population-based registry can be exploited in synergy with health databases, to provide evidence related to disease outcomes and therapies and to assess the burden of disease, relying on a large cohort of cases. Building an integrated archive of data from multiple databases linking a cohort of patients to their comorbidities, clinical outcomes and survival, is important both in terms of treatment and prevention.

Clinical Treatment Options in Scleroderma: Recommendations and Comprehensive Review

There are two major clinical subsets of scleroderma: (i) systemic sclerosis (SSc) is a complex systemic autoimmune disorder characterized by inflammation, vasculopathy, and excessive fibrosis of the skin and multiple internal organs and (ii) localized scleroderma (LoS), also known as morphea, is confined to the skin and/or subcutaneous tissues resulting in collagen deposition and subsequent fibrosis. SSc is rare but is associated with significant morbidity and mortality compared with other rheumatic diseases. Fatal outcomes in SSc often originate from organ complications of the disease, such as lung fibrosis, pulmonary artery hypertension (PAH), and scleroderma renal crisis (SRC). Current treatment modalities in SSc have focused on targeting vascular damage, fibrosis, and regulation of inflammation as well as autoimmune responses. Some drugs previously used in an attempt to suppress fibrosis, like D-penicillamine (D-Pen) or colchicine, have been disappointing in clinical practice despite anecdotal evidence of their advantages. Some canonical medications, including glucocorticoids, immunosuppressants, and vasodilators, have had some success in treating various manifestations in SSc patients. Increasing evidence suggests that some biologic agents targeting collagen, cytokines, and cell surface molecules might have promising therapeutic effects in SSc. In recent years, hematopoietic stem cell transplantation (HSCT), mostly autologous, has made great progress as a promising treatment option in severe and refractory SSc. Due to the complexity and heterogeneity of SSc, there are currently no optimal treatments for all aspects of the disease. As for LoS, local skin-targeted therapy is generally used, including topical application of glucocorticoids or other immunomodulatory ointments and ultraviolet (UV) irradiation. In addition, systemic immunosuppressants are also utilized in several forms of LoS. Here, we comprehensively discuss current treatment options for scleroderma, encompassing old, new, and future potential treatment options. In addition, we summarize data from new clinical trials that have the potential to modify the disease process and improve long-term outcomes in SSc.

Systemic sclerosis overlap and non-overlap syndromes share clinical characteristics but differ in prognosis and treatments

OBJECTIVES

To screen for concomitant autoimmune disease in patients with systemic sclerosis (overlap SSc) and to describe their clinical characteristics and prognosis.

METHODS

This was a two-center retrospective observational study. Patients diagnosed with SSc according to the 2013 ACR-EULAR scleroderma classification criteria were screened for concomitant rheumatoid arthritis (RA), Sjögren syndrome (SgS) and systemic lupus erythematosus (SLE). Patient characteristics were retrieved from the medical records and were compared to those of a non-overlap SSc cohort.

RESULTS

Among the 534 SSc patients studied, thirty-four (6.4%) were identified as having overlap SSc. There were 21 (3.9%) patients with RA, 14 (2.6%) with SgS and 4 (0.7%) with SLE (5 patients had 2 AISD) . The disease phenotype of overlap SSc was similar to that of non-overlap SSc in terms of cutaneous phenotype, prevalence of pulmonary arterial hypertension, interstitial lung disease, digital ulcers and mortality. Using a multivariate Cox model, age (HR = 1.04, 95% CI [1.02-1.07]), the modified Rodnan skin score (HR = 1.08 per point, 95% CI [1.05-1.11]), and the presence of concomitant SgS (HR = 3.79, 95% CI [1.38-10.40]) were significantly associated with mortality. Overlap SSc were more likely to receive corticosteroids (85.3% vs. 45%, p < 0.001), immunosuppressive drugs (82.4% vs. 49.2%, p < 0.001) and biologics (52.9% vs. 3.8%, p < ZZ0.001).

CONCLUSIONS

While overlap and non-overlap SSc shared common characteristics, patients with SgS/SSc had a higher risk of mortality, and those with RA/SSc received more corticosteroids, methotrexate and biologics. Screening for an associated AISD should be promoted since their co-occurrence with SSc may affect prognosis and treatments.

Targeted delivery in scleroderma fibrosis

Systemic sclerosis (SSc) is considered one of the most challenging and difficult to treat among rheumatic disorders, due to its severity, multiorgan manifestation and different outcomes. It manifests fibrosis in different organs, mostly in skin and lungs. The skin fibrosis expression is considered the first sign of the disease and usually it is followed by internal organ fibrosis. An aberrant immune system activation seems to relate to the expression of the disease, but even environmental influences and dysregulation of many molecules signalling pathways are involved in the development of the disease. Current therapies are limited and characterized by multiple side effects: systemic route is the elective administration route, which decreases patient adherence to the therapy, as they are often already bothered by pain and disfigurement. Treatments available are organ-based, originally indicated for other conditions and there is no therapy available to reduce the fibroblast population size within existing fibrotic lesions. Disease-modifying therapies or immunomodulatory agents that are highly effective in other rheumatic diseases have shown disappointing results in SSc. There are thus no standardized and effective treatments for this disease, and there are even unanswered questions related to the insurgence of the pathology and all the mechanisms involved. An ideal approach could be considered "targeted therapy" that will be an increasingly attainable objective insofar as our understanding of the disease improves. The advantages in identifying the molecule and the signalling pathways involved in the pathology have helped to find some novel compounds for the therapy of scleroderma fibrosis or following innovative uses for already-approved drugs, corroborated by many clinical studies.

Clinical trial protocol: PRednisolone in early diffuse cutaneous Systemic Sclerosis (PRedSS)

Background:

Many of the painful, disabling features of early diffuse cutaneous systemic sclerosis have an inflammatory component and are potentially treatable with corticosteroid therapy. These features include painful and itchy skin, fatigue and musculoskeletal involvement. Yet many clinicians are understandably reluctant to prescribe corticosteroids because of the concern that these are a risk factor for scleroderma renal crisis. The aim of PRedSS (PRednisolone in early diffuse cutaneous Systemic Sclerosis) is to evaluate the efficacy and safety of moderate dose prednisolone in patients with early diffuse cutaneous systemic sclerosis, specifically whether moderate dose prednisolone is (a) effective in terms of reducing pain and disability, and improving skin score and (b) safe, with particular reference to renal function.

Methods:

PRedSS is a Phase II, multicentre, double-blind randomised controlled trial which aims to recruit 72 patients with early diffuse cutaneous systemic sclerosis. Patients are randomised to receive either prednisolone (dosage approximately 0.3 mg/kg) or placebo therapy for 6 months. The two co-primary outcome measures are the difference in mean Health Assessment Questionnaire Disability Index at 3 months and the difference in modified Rodnan skin score at 3 months. Secondary outcome measures include patient reported outcome measures of itch, hand function, anxiety and depression, and helplessness.

Results:

Recruitment commenced in December 2017 and after a slow start (due to delays in opening centres) 25 patients have now been recruited.

Conclusion:

PRedSS should help to answer the question as to whether clinicians should or should not prescribe prednisolone in early diffuse cutaneous systemic sclerosis.

Undifferentiated connective tissue disease at risk for systemic sclerosis: Which patients might be labeled prescleroderma?

Undifferentiated Connective Tissue Disease at risk for Systemic Sclerosis (UCTD-risk-SSc), otherwise referred to as very early-early SSc (very early-early diagnosis of systemic sclerosis VEDOSS), is a condition characterized by Raynaud's phenomenon (RP) and either SSc serum marker autoantibodies or a capillaroscopic scleroderma pattern or both, but without satisfying classification criteria for SSc neither features consistent with SSc sine scleroderma. Approximately half the UCTD-risk-SSc patients develop definite SSc over 5-10 years of follow-up. Identifying patients who will undergo such evolution is an unmet need. Predicting at onset which patients with RP are going to develop SSc over time has long been a research objective and still is an unaccomplished task. The present review is devoted to the critical analysis of the nosographic boundaries of the condition and of items predictive of evolution including serological, capillaroscopic and circulating markers. A weighted score, based on serum antinuclear antibody titre, serum marker antibodies positivity and avascular areas has been developed and may identify in the meanwhile patients to be labeled prescleroderma i.e. those probably developing SSc over time. Future research should be directed to investigate unexplored features, validate and improve the performance of the score and highlight the involved pathways to be contrasted in order to identify a targeted therapy hampering the development of overt SSc.

The systemic sclerosis patient in the COVID-19 era: the challenging crossroad between immunosuppression, differential diagnosis and long-term psychological distress

COVID-19 is a world health emergency which may inevitably affect the management of a complex autoimmune disease such as systemic sclerosis (SSc). Several SSc patients are frail and, in this pandemic, need a careful protection. The COVID-19 infection might complicate the clinical scenario of interstitial lung disease (ILD) in SSc because it determines a severe pneumonia characterized by radiological features similar to SSc-ILD. The striking CT similarities between the 2 diseases make it difficult to distinguish a worsening of SSc-ILD from COVID-19-ILD superinfection. Moreover, other aspects, like isolation during lock down, may cause a significant psychological stress which will pile up on the already difficult contact with the patients for a routine check-up. Moreover, the drug shortage is a real problem in these times. For these reasons, the rheumatologist in daily clinical practice should carefully differentiate the possible COVID-19 infection in order to optimize the patient management. Therefore, the challenge in everyday life will be to achieve in due time the differential diagnosis as well as the long-term psychological impact.Key Points• SSc patients should be encouraged to continue their chronic therapy; in case of immunosuppressive therapy it must be discontinued for safety in case of COVID-19 infection.• Psychological support must be guaranteed to every SSc patients.• COVID-19 pneuminia is hard to distinguish from an interstitial lung disease due to SSc lung involvment.• Data sharing is fundamental for an optimal managment of SSc patients during COVID-19 pandemia.

Gender-related differences in systemic sclerosis

Systemic sclerosis (SSc) is a complex autoimmune connective tissue disease which is characterised by autoimmunity, widespread tissue fibrosis of the skin and internal organs, and vasculopathic alterations. SSc is more common in women but has a more severe expression of disease including internal organ-based complications and higher mortality in men. The extant literature shows that although important pathophysiological sex differences are present in SSc, behavioural differences (e.g. higher smoking rates in men) and occupational exposures may contribute to poorer outcomes in men with SSc. The higher death male death rate in the general population and greater prevalence of lung fibrosis are likely the key factors responsible for excess mortality found in men. Other important factors include (but are not limited to) a greater prevalence of the disease subset, delayed time to diagnosis, and higher disease activity in early disease in men. SSc carries a significant burden of disease-related morbidity; however, no qualitative studies to date have focussed on gender differences in SSc. The purpose of this review is to provide a comprehensive overview of gender differences in SSc including (but not limited to) epidemiology, pathophysiology, clinical expression of disease, mortality, SSc in transgender individuals, and psychosocial aspects of disease.