Short-term effects of ambient air pollution on respiratory health in children with asthma

Respiratory health effects due to air pollution have been well documented in
the past decades. The relation between short-term exposure to air pollutants
and incidence of asthma symptoms in children is one of the endpoints included
in the report of the World Health Organization to fully assess the health
impact of outdoor air pollution. However, the evidence base for quantification
was judged as too uncertain to include in the main health impact assessment.
Furthermore, most studies are relatively old, e.g. over 20 years have passed
since the last panel studies on the effects of air quality on asthma-related
symptoms have been conducted in the Netherlands, while pollutant concentrations
and types of major pollutants have changed over the past decades. Exposure to
air pollution is often estimated by one or two central monitoring stations.
This may lead to measurement error and potentially to underestimation of air
pollution risks. A recently developed air quality measurement network in the
city of Eindhoven measures key air pollutant concentrations at a fine spatial
and temporal resolution.

The main objective of the panel study is to evaluate the associations between
short-term variation of concentrations of key air pollutants (NO2, PM2.5, PM10,
and ultrafine particles), measured on a fine spatial and temporal resolution,
and short-term variation of asthma-related symptoms, on-demand asthma
medication use and lung function in children with asthma.

Panel study in 100 children with asthma, with daily registration of respiratory
symptoms, medication use and lung function in a four month period. Related to
daily measurements of key air pollutants.

The total participation time for each child and its parents is 4 months. During
these 4 months the child will be visited at the home address three times by a
research assistant. A short diary will be filled out daily, under parental
supervision, taking 2-3 minutes. Twice daily a simple lung function measurement
will be performed for a period of 2 months within those 4 months. There is no
risk associated with participation. Participants do not personally benefit from
the outcomes of the panel study. Although the study will be performed in
Eindhoven, the results may also be applicable to cities with similar
concentrations of pollutants and other factors.