Endothelial Biomarkers of Systemic Sclerosis-associated Pulmonary Hypertension

Study Overview
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Brief Summary
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Systemic sclerosis (SSc, AKA scleroderma) is an autoimmune condition characterized by endothelial damage and progressive fibrosis of the skin and internal organs. One of the leading causes of morbidity and mortality in patients with SSc is pulmonary hypertension (PH), which is estimated to occur in up to 31% of high risk SSc patients. Early detection of patients with SSc-PH may lead to improved outcomes and although there have been concerted efforts to accurately screen for SSc-PH, these patients continue to present with advanced disease and suffer from poor survival. Therefore, better methods to screen for patients with PH and, perhaps more importantly, to screen for those at risk for PH development are desperately needed. Since PH and SSc are disorders originating from the endothelium, biomarkers that reflect endothelial damage are very promising tools to identify early disease. Such potential biomarkers include endothelial microparticles, asymmetric dimethylarginine (ADMA), pentraxin-3, and soluble endoglin. No previous study has used a combination of these biomarkers to detect the presence of PH in patients with SSc, or studied the novel concept of exercise-induced changes in biomarker levels. The investigators will collect the above listed endothelial biomarkers before and after exercise, and combine these levels with exercise echocardiogram findings, and routine clinical information to derive a composite detection score for the early identification of systemic sclerosis-associated PH.

Official Title
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Novel Screening Strategy for Systemic Sclerosis-associated Pulmonary Hypertension Incorporating Endothelial Biomarkers

Conditions
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Scleroderma, Pulmonary Hypertension

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Age >18 years 2. Meet American College of Rheumatology criteria for SSc Exclusion Criteria: Chronic kidney disease (estimated creatinine clearance <50mL/min) Uncontrolled hypertension (diastolic blood pressure>120mmHg) Acute coronary syndrome within the past 6 months Chronic obstructive pulmonary disease Diabetes mellitus Hemolytic anemia Active tobacco abuse

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Systemic sclerosis patients w/ PH<br>Pulmonary hypertension will be defined as a mean pulmonary artery pressure≥25mmHg on right heart catheterization | Other: No intervention<br>* No intervention<br>|
| Systemic sclerosis patients w/o PH<br>Pulmonary hypertension will be excluded based on all of the following echocardiogram features: estimated systolic pulmonary artery pressure<35mmHg and absence of right atrial or right ventricular (RV) enlargement and lack of qualitative RV dysfunction. If a subject has any of these echo features, they will be referred for right heart catheterization (RHC) and included in the appropriate group based on their RHC results. | Other: No intervention<br>* No intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite pulmonary hypertension detection score | A score will be derived by incorporating biomarkers, exercise echo results, pulmonary function tests, autoantibody status, 6-minute walk results, etc. into a linear regression model | At baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite pulmonary hypertension detection score | A score will be derived by incorporating biomarkers, exercise echo results, pulmonary function tests, autoantibody status, 6-minute walk results, etc. into a linear regression model | At 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Biomarkers, Endothelial microparticles