AsthmaVent - Effect of Mechanical Ventilation on Asthma Control in Children (AsthmaVent)

AsthmaVent is a multi-center study, investigating the association between indoor air quality and childhood asthma.

In Denmark, we spend more and more time indoors. Our houses are built airtight to save energy and are difficult to ventilate. We are thus more exposed to our indoor air than ever before. We know that indoor air contains many different components that can affect our airways inappropriately and particularly children with asthma, who have sensitive airways are sensitive to these components. The AsthmaVent project examines whether increased ventilation is able to improve the indoor environment to such an extent that the asthma disease control, for children with asthma and house dust mite allergy improves, resulting in need for less medication.

Previous studies have pointed towards a beneficial effect of mechanical ventilation, on both the indoor air quality and on children's health and quality of life. There is not currently a consensus in this area, as studies so far have not been large or good enough to confidently determine the effect.

This project is big and is designed so that it takes into account the sources of error seen in previous studies on the topic.

We include, over a 3-year period (2012-2014), a total of 80 children with asthma and house dust mite allergy aged 6-18 years, from pediatric departments in Aarhus, Odense, Kolding, Randers and Herning. They are divided into two groups, receiving either active ventilation or placebo ventilation, meaning a non-functioning ventilation system that just recirculates the air in the room. Ventilation systems are installed in the fall and winter and ventilate the child's bedroom during 9 months. Indoor air quality and asthma control are assessed every 3 months, both at home visits were air quality and allergen levels of house dust mites are studies and at visits to the outpatient clinics with control of asthma parameters and quality of life.

The project involves collaboration between several institutions with an interest in indoor air quality in relation to allergies and asthma and with great expertise in the field.The project was initiated by CISBO (Centre for Indoor Environment and Health in Dwellings), a center consisting of several institutions in Denmark dealing with indoor environment: Department of Public Health at Aarhus University and University of Copenhagen, Danish Building Research Institute and the Technical University of Denmark.

Since asthma is the most common chronic childhood disease in Denmark and since the development of allergies and asthma has high social and personal costs, it is important for both society and the individual family, to find out whether simply improving the indoor air quality by increased ventilation can lead to an improvement in asthma disease control.