DELTA DESCRIBE: the French Collaborative Project

Study Overview
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Brief Summary
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Our global objective is to draw up a photograph of HDV patients over one year in metropolitan France and identify the barriers of screening and care. The investigator suspects a mismatch between HBV and HDV screening, the first step for specialized care pathway in metropolitan France.

Detailed Description
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Hepatitis Delta virus (HDV) infection is a significant public health disease causing up to 18% of cirrhosis and 20% of hepatocellular carcinoma (HCC) and new therapeutic options are now available. In France, very few epidemiological studies, mainly focused on specific pre-selected hospital populations, are available. There is a crucial need for data in terms of Delta knowledge, suitability of screening, type of prescribers and treatment access. The investigator proposes a retrospective study in order to describe the number of HDV tests (anti-HDV and HDV RNA) performed in metropolitan France and compare it to the potentially expected one, estimated from the number of HBV screening tests performed in one year, from 2016 to 2020. The investigator will also evaluate the number of HCV and HIV screening tests prescribed over the same period and the HDV PCR techniques used. This study will be based on one hand on data from the French Health insurance (first step) and on the other hand on data from private and hospital laboratories (second step). The second step will allow to identify the prescriber of the Delta tests and the HDV positive patients and precise their profile and their medical care. After an initial analysis of the results, The investigator will propose solutions to the barriers encountered and adapted to the identified targets.

Official Title
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DELTA DESCRIBE: the French Collaborative Project

Conditions
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Hepatitis D

Intervention / Treatment
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* Diagnostic Test: Patients co-infected HBV/HDV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: >18 years at the second step HDV RNA positive patients identified at the second step Patients non opposed to the collection of their data Exclusion Criteria: Opposition expressed by the patients for the collection of their data

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

| Intervention/Treatment |
| --- |
|Diagnostic Test: Patients co-infected HBV/HDV|Step 1: collection of SNDS data from 2016 to 2020 Snapshot of the prescription of the Delta tests and the tests usually prescribed simultaneously (HBV but also HIV and HCV) in one year. The investigator will collect the number of tests performed once for a given patient: anti-HDV, HDV RNA, HBsAg, anti-HCV, anti-HIV, and for each test, the description of the profile and the geographical distribution of prescribers in the metropolitan area; the description of age and sex of the patients screened. Step 2: collection of anti-HDV and RNA tests performed in French private and Public laboratories over the year 2019 Anti-HDV and HDV RNA are subcontracted by most private laboratories to two specialized biology companies. Number of HDV tests prescribed, technique used, number of positive tests and name of the requesting laboratory will be collected. The investigator will then go back to the prescriber of the positive tests, identify the patient, his epidemiological profile and his medical care.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of anti-HDV and HDV RNA tests performed from 2016 to 2020 in metropolitan France | - Number of anti-HDV and HDV RNA tests performed from 2016 to 2020 in metropolitan France according to the French Health insurance database.(SNDS) | 12 months | 
| Number of anti-HDV and HDV RNA tests expected | - Number of anti-HDV and HDV RNA tests expected over the same period (calculated from the estimate of the positivity of HBsAg tests prescribed in France) | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of anti-HCV, anti-HIV and HBs Ag tests performed in metropolitan France from 2016 to 2020 | Number of anti-HCV, anti-HIV and HBs Ag performed in France from 2016 to 2020 (SNDS data). | 12 months | 
| Age, sex, residence department and profile of prescribers of patients receiving HDV, HBV, HIV and HCV tests | Global epidemiological characteristics (age, sex, residence department), of patients receiving HDV, HBV, HIV and HCV tests on the 2016-2020 period, with the profile of prescribers. (SNDS data). | 12 months | 
| Number of anti-HDV and HDV RNA tests performed in 2019 by the laboratories in metropolitan France | Number and result of anti-HDV and HDV RNA tests performed in 2019 (Private and Public laboratories data | 12 months | 
| Age, sex, profile of the prescribers of HDV RNA positive patients identified by the laboratories in 2019 | Age, sex, profile of the prescribers, treatment modalities (if available) of HDV RNA positive patients identified at the second step (Private and Public laboratories data) | 12 months | 
| Rate of use of the different HDV PCR techniques by the laboratories in 2019 | HDV PCR techniques used (Private and Public laboratories data) | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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HBs Ag, Delta hepatitis, Screening, Reflex testing