The project is to measure exposure to outdoor and indoor air pollutants in asthma patients in order to show a possible association between variation in pollutant exposure and the occurrence of exacerbations in these patients

Asthma is a chronic airway disease affecting between 6% and 7% of the French adult population. Asthma is responsible for nearly 1000 deaths each year in France. Air pollution (indoor and outdoor) is responsible for 7 million deaths each year according to the World Health Organization (WHO) assessment published in 2018, including 65,000 in France. Studies monitoring exposure to indoor air pollutants are few in number in asthmatic patients. Very little research has been devoted to continuous monitoring of indoor air quality in homes. Our hypothesis is that variation in exposure to indoor air pollutants, in relation to outdoor air, would have an impact on the occurrence of exacerbations in asthmatic patients.

Inclusion Criteria:

• Patient over 18 years of age,
• Patient with a confirmed diagnosis of asthma for at least 12 months as defined by the investigator,
• Patient with at least 4 asthma exacerbations in the last year
• Patient sleeping at least 6 nights per week in the same home

Exclusion Criteria:

• Patient who is an active smoker or living with an active smoker,
• Patient with a diagnosis of COPD, ABPA or associated pulmonary fibrosis,
• Patient with an asthma exacerbation within 15 days prior to the inclusion visit,
• Patient with known occupational exposure,
• Patient living in a dwelling that does not allow the installation of sensors (inability to connect the sensor to the power supply, no location for the outdoor sensor...)
• Patient who plans to move in the next 6 months,
• Patient with a life expectancy of less than 6 months,
• Patient who has someone living in their household also included in EXAP,
• Patient who lives in an apartment and does not have a balcony or space for the outdoor sensor,
• Pregnant or breastfeeding women,

The study population will consist of adult men and women recruited from the active file of asthma patients followed at the Nantes University Hospital, the Saint Nazaire Hospital, the Châteaubriant Nozay Pouancé Hospital and the Erdre et Loire Hospital. Regardless of the type of asthma, patients will be potentially included if they have a minimum of 4 exacerbations during the year preceding inclusion in the EXAP project>. Participation in other non-interventional research is allowed during the study unless this research increases the number of exacerbations.