Liver Fibrosis and Gut Microbiota in Patients With Psoriasis Vulgaris and Rheumatoid Arthritis on Methotrexate

Study Overview
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Brief Summary
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While methotrexate (MTX) remains a treatment of choice for patients with rheumatoid arthritis (RA), psoriasis (PsO) and psoriatic arthritis (PsA), long-term MTX use has been shown to be associated with liver fibrosis and cirrhosis in these patients. In addition, gut dysbiosis has been found to be associated with liver fibrosis and cirrhosis via the gut-liver axis, underscoring the potential role of gut microbiota and bacterial translocation in the pathogenesis of chronic liver diseases in these patients. In this study, we aim to assess the prevalence of advanced liver fibrosis or cirrhosis among these patients on MTX treatment compared to those without, using transient elastography. We also aim to identify the possible risk factor(s) for advanced liver fibrosis or cirrhosis among them. Further, we aim to characterize the difference in fecal microbiota patterns among these three groups of patients. Using a cross-sectional, prospective cohort design, this study will enroll approximately 600 eligible patients, including 300 patients with PsO/PsA and 300 patients with RA, to examine the following hypotheses: Patients on higher cumulative dose of MTX will have higher prevalence of advanced liver fibrosis or cirrhosis compared to those on lower cumulative dose of MTX; Patients with MTX use will have higher prevalence of advanced liver fibrosis or cirrhosis compared to those without MTX use; The fecal microbiota composition will be different between patients with and without MTX treatment; and The fecal microbiota composition will be different between patients with and without advanced fibrosis/cirrhosis while on MTX treatment.

Official Title
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A Comparison Study of Liver Fibrosis and Its Association With Gut Microbiota in Patients With Psoriasis Vulgaris and Rheumatoid Arthritis on Methotrexate

Conditions
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Psoriasis Vulgaris, Rheumatoid Arthritis, Fibrosis, Liver

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 18 to 85 years Have regular follow up in Dermatology/ Rheumatology clinics of Queen Mary Hospital Diagnosed with PsO/PsA or RA Chinese ethnicity Exclusion Criteria: Age below 18 years or above 85 years Known decompensated cirrhosis Pregnancy or breastfeeding Unstable medical illness or active infection Unable to provide written consent Unable to adhere to the protocol Unable to read and/or write Chinese language On anticoagulant/ antiplatelet treatment Abnormal platelet count <150 Known disease/condition with prolonged INR/bleeding tendency

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| PSO/PSA<br>Patients diagnosed with psoriasis or psoriatic arthritis | |
| RA<br>Patients diagnosed with rheumatoid arthritis | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of patients with advanced liver fibrosis or cirrhosis | We will measure the number of patients with significant fibrosis (defined as having liver stiffness ≥ 7.5 kPa in transient elastography), and among those who undergo biopsy, the number of patients whose biopsy specimen is of Roenigk grades 3b or 4 | At the time of the assessment procedure | 
| The type and abundance of fecal microbiota patterns | We will measure the type and abundance of various bacteria/viruses in specimens; alpha diversity within a specimen and beta diversity between groups of specimen; specific taxa that differ significantly between groups; and metabolic profiles and functional pathways associated with change in gut microbiota | At the time of the assessment procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The risk factors of liver fibrosis | Risk factors to be examined will include demographic variables such as age and gender, cumulative dose of MTX, gut dysbiosis, duration of disease, co-morbidities, hepatic steatosis, liver stiffness, and other potential factors | At the time of the assessment procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Methotrexate, Microbiota