Asthma is one of the most prevalent chronic respiratory diseases, with potential lifethreatening impacts. Indeed, asthma is still responsible for about a thousand deceases per year in France, and constitutes a public health problem in our country as in many countries in the world. The economic burden of asthma is also very high, in terms of health care, and indirect costs including lost work and lost school days.

A few international and French studies have shown a positive clinical impact of Medical Indoor Environment Counselors (MIECs) visiting homes of asthma patients, mainly pediatrics. It has been proposed that MIECs could contribute to reduce patient exposure to many allergens and irritants, among them, house dust mite allergens, formaldehyde or molds. Most of the studies that show a significant decrease of hospitalization or visit in an emergency ward for asthma are monocentric and study the eviction of 1 such identified risk factor. By contrast, meta-analysis underline that additional studies are needed to evaluate the effectiveness of these interventions in adults, in a multicentric and controlled manner, with both clinical, environmental and economical endpoints.

Methodology/Study schedule :

A prospective multicenter randomised, open label, controlled trial with blind evaluation of the primary evaluation criterion on three parallel groups of patients.

Procedures :

Home intervention of MIECs that comprise diagnostic of allergen/irritant exposure (after sampling), advices for allergen/irritant avoidance and follow up of advice compliance.

After randomisation and agreement of the patient and the family, the " intervention group " will benefit from a first home intervention of a MIEC during the 4 weeks following inclusion, then a final visit at the end of the study after 12 months.

Two comparative groups will be identified :

• the " control group " who will benefit from a first home intervention of a MIEC but without advices (only audit + sampling), then a final and a complete visit at the end of the study
• a " non intervention " group with no initial visit, but who will benefit from a complete home intervention of a MIEC at the end of the study.

Substantial modification of the 20th of June, 2016 : Modification of the design : change into a 2 parallel groups evaluation Justification: At its meeting of June 1, 2016, considering the inclusion difficulties, the Scientific Council decided to give up the "Control" group.

The study design is then : a prospective multicenter randomised, open label, controlled trial with blind evaluation of the primary evaluation criterion on three parallel groups of patients.

The objective is to recruit 50 to 70 patients by arm.

Expected findings and impact :

If our hypothesis that home intervention of MIECs are cost-effective on asthma control, then it is relevant to include such service in the medical care during the management of asthma patients with a reimbursement by the social security.

Inclusion Criteria:

• age greater than or equal to 6 years and less than 45 (<45 years),
• patients with an eligible control level of asthma,
• sensitization to one or more allergens demonstrated during the last 36 months with prick tests (papules with a diameter > 3 mm compared to a negative control or > 50% of positive control) and/or specific IgE detection (> 0.10 U/mL),
• patients > 15 years presenting with a reversibility to ß2-agonists > 200 mL and/or > 12% compared to the initial FEV1 value (test performed at least once in life) or patients ≥ 6 years and ≤ 15 years presenting with a reversibility to ß2-agonists > 200 mL and/or > 12% compared to the initial FEV1 value (at least once in the life) and/or a positive metacholine challenge (at least once in the life),
• patients sleeping > 6 nights per week in the same house
• individuals affiliated to 1 of the 3 French social security (for matching data from French social security via SNIIRAM system),
• Only one patient per dwelling,
• Patient oral consent (written attestation by investigator)

Exclusion Criteria:

• chronic obstructive pulmonary disease (COPD),
• identified occupational asthma,
• Move within the 6 months before home intervention or predicted during the first year of inclusion,
• advices provided during the 2 years before inclusion during a home intervention of a MIEC
• active smokers or smoker who given up smoking less than 5 years ago, with a consumption of more than 10 years of 20 cigarettes/day, OR smoker who given up smoking more than 5 years ago, with a consumption of more than 20 years of 20 cigarettes/day,
• patients < 18 years for whom the parents (or legal guardian) are opposed to the inclusion in ECENVIR study,
• Major people being the object of a legal protection (protection(saving) of justice, guardianship, supervision(guardianship)) and private persons of freedom

Substantial modification of the 20th of June, 2016 : Modification of the design : change into a 2 parallel groups evaluation Justification: At its meeting of June 1, 2016, considering the inclusion difficulties, the Scientific Council decided to give up the "Control" group.

The study design is then : a prospective multicenter randomised, open label, controlled trial with blind evaluation of the primary evaluation criterion on three parallel groups of patients.

The objective is to recruit 50 to 70 patients by arm.

The Control group will still be described.