The project titled "Domestic Environmental Exposure and Progression of Progressive or Stable Fibrosing Interstitial Lung Diseases: An Exploratory Case-Control Study" is a Category 3 study involving 60 patients with progressive or stable fibrosing interstitial lung diseases (ILDs). These patients are matched based on the same ILD subtype and their use or non-use of antifibrotic medication. The study aims to thoroughly describe the domestic environment of these patients and investigate the associations between the progression of pulmonary fibrosis and: i) The presence of pollutants and risk factors in the home, including concentrations of nitrogen dioxide, volatile organic compounds, aldehydes, fine particles, mold, dust mite allergens, building defects, and lifestyle habits that increase pollutant exposure. ii) The ambient air quality at the patients' addresses. Occupational exposures will also be considered in the analysis. This project is designed to enhance our understanding of how an unfavorable domestic environment impacts the progression of pulmonary fibrosis and to evaluate the effects of the CMEI (Comprehensive Environmental and Indoor Audit) on patients' ability to manage identified risk factors within their homes, their respiratory health, and their medical diagnosis. The CMEI audit is a preventive measure that could serve as a significant intervention to alter patient behavior, reduce exposure, and improve health outcomes. This project is sponsored by the Environmental Health Laboratories Department, in collaboration with Unit 1018 of the Research Center in Epidemiology and Population Health (CESP), and two investigative centers: Tenon Hospital and Paris Saint-Joseph Hospital.

Inclusion Criteria:

• Patient aged over 18 years
• Patient affected by one of the following interstitial lung diseases (ILDs): Idiopathic Pulmonary Fibrosis (IPF), Nonspecific Interstitial Pneumonia (NSIP), Pneumoconioses, ILDs associated with autoimmune features, Pleuroparenchymal Fibroelastosis (PPFE), Chronic Hypersensitivity Pneumonitis (CHP) whose etiology is not primarily related to the domestic environment, Stage 4 fibrosing sarcoidosis, unclassifiable ILDs.
• ILD patient with progressive fibrosis over the past 12 months (case group)
• ILD patient with non-progressive fibrosis over the past 12 months (control group)
• Patients without reduction in the treatment of interstitial lung disease in the 12 months prior to inclusion, patients without treatment can be included
• Matching "1 progressive fibrosis" / "2 non-progressive fibrosis":
• Same ILD diagnosis
• Use of antifibrotic treatment for both paired patients or absence of antifibrotic treatment for both paired patients
• Both patients should preferably be matched within 3 months to limit significant contrasts in lifestyle and housing use related to the season
• Patient who has received information about the protocol and does not object to participating
• Patient affiliated with or beneficiary of a social security scheme or universal health coverage

Exclusion Criteria:

• Patient who has already received advice from a CMEI (Environmental and Occupational Medicine Consultation Center) in the past 12 months
• Patient who has recently moved into their home (less than 1 year)
• Patient living less than 6 months per year in the home to be investigated
• Patient followed in psychiatry for a severe condition
• Patient who does not speak French and is not accompanied by a person who shares their home and speaks French to act as a translator
• Patient refusing to consent to participate in the research
• Patient not living in Île-de-France
• Patient with non-chronic Hypersensitivity Pneumonitis related to the domestic environment
• Patient with sarcoidosis (except stage 4 fibrosing sarcoidosis)
• Adult patient under legal protection and unable to give consent

The recruited patients will be divided into two groups:

• The "case" group will consist of patients with a fibrosing interstitial lung disease (ILD) who meet one of the criteria for fibrotic progression during the 6 months prior to inclusion.
• The "control" group will be composed of patients with a fibrosing ILD who do not meet any of the criteria for fibrotic progression during the 6 months prior to inclusion.

The proposed criteria for progression, which will be used in our project, are:

Relative decrease in FVC ≥ 10%, Relative decrease in FVC ≥ 5% and a decrease in DLCO ≥ 15%, Relative decrease in FVC ≥ 5% and worsening of fibrotic signs on a scan, Relative decrease in FVC ≥ 5% and worsening of symptoms, Worsening of symptoms and fibrotic signs on a scan.