Effects of indoor particulate matter exposure on daily asthma control

Household dust often contains aeroallergens, such as the house dust mite antigen Der p 1. It has been proposed that overnight exposure to particulate matter from bedding and other sources may be an important driver of atopic asthma. Whether variability in overnight particulate matter exposure is a significant determinant of asthma control is unknown.

To test the hypothesis that overnight particulate matter exposure is associated with day-to-day symptoms, lung function, and airway inflammation in patients with asthma who are sensitized to house dust mite.

We undertook a prospective, single-center panel study in 28 adults with asthma and house dust mite sensitization. Overnight exposure to particulate matter was measured using a commercially available indoor air quality monitor. Symptom scores, peak expiratory flow, and exhaled nitric oxide were measured and electronically recorded daily. Participants were followed up for 12 weeks and attended study visits every 4 weeks, at which they underwent spirometry and completed the Asthma Control Questionnaire and Asthma Quality of Life Questionnaire. Data were analyzed using cross-correlation and linear mixed-effects models.

No significant associations were observed between overnight particulate matter exposure and clinical outcomes measured daily or at study visits.

Natural variability in overnight particulate matter exposure does not appear to be a major determinant of daily asthma control in patients with asthma and house dust mite sensitization.