Occupational Respiratory Allergies and Gene-environment Interactions

Study Overview
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Brief Summary
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The purpose is to compare clinical, functional, professional and socio-economical characteristics of patients with occupational asthma and work aggravated asthma. Secondary purposes are: to evaluate diagnostic value of new non-invasive techniques such as exhaled nitric oxide and cytology of induced expectoration; to estimate medical-social becoming of diagnosed work-related asthma after one year; to establish a biobank of blood samples of individuals with work related asthma for measurement of cytokines and search for genetic polymorphisms associated with asthma.

Detailed Description
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Participants with work related asthma or suspected work related asthma will obtain a precise diagnosis concerning severity and control of respiratory disorder and also the possible effect of professional environment on the disorder. Their medical care and medico-legal care, in case of recognition of occupational disease, could be ameliorated. In general, this study will allow the harmonization of diagnostic care and medical, medico-professional and medico-legal management of cases of work related asthma in specialized hospitals.

Official Title
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Occupational Respiratory Allergies and Gene-environment Interactions

Conditions
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Work Related Asthma

Intervention / Treatment
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* Other: Blood sample


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Patient consulting for suspected work-related asthma in one of hospitals participating to the study Exclusion Criteria: Patient refusing to participate Pregnant or breastfeeding women Individual in life-threatening emergency Hospitalized patient Patient in a health or social institution Person deprived of liberty Person with total occupational disability Retired person Person diagnosed as non-asthmatic Asthmatic person already enrolled in a clinical trial of bio-therapy to treat asthma

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 65 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 |
| --- | --- |
| Occupational Asthma<br> | Other: Blood sample<br>* Biobank. Analysis of cytokines and DNA polymorphisms<br>|
| Work Aggravated Asthma<br> | Other: Blood sample<br>* Biobank. Analysis of cytokines and DNA polymorphisms<br>|
| Non-Work-Related Asthma<br> | Other: Blood sample<br>* Biobank. Analysis of cytokines and DNA polymorphisms<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Classification of suspected work-related asthma in occupational asthma, work aggravated asthma, non-work-related asthma | Interpretation of diagnostic algorithm of study | Inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Nitric oxide level | Bronchial inflammation marker | Inclusion | 
| Cytology of induced expectoration | Bronchial inflammation marker | Inclusion | 
| Nonspecific bronchial hyperreactivity evaluated with metacholine bronchial challenge test and/or isocapnic hyperventilation test |  | Inclusion | 
| Control of asthma symptoms evaluated with Asthma Control test and peak exploratory flow |  | Inclusion | 
| Severity of symptoms |  | Inclusion | 
| Costs of different types of asthma | Direct and induced costs | Inclusion and after 1 year |