Association between Der p 1 concentration and peak expiratory flow rate in children with wheeze: a longitudinal analysis.

BACKGROUND

House dust mite (HDM) allergen exposure has been well documented as an environmental cause of airway hyperresponsiveness (AHR) and asthma symptoms. The relationship between asthma morbidity and exposure to low concentrations of HDM allergen suggests that there may be no safe exposure threshold to HDM allergen.

OBJECTIVE

We aimed to investigate the associations between Der p 1 in bedding and lung function in 30 children with a history of wheezing in a longitudinal study.

METHODS

After a cross-sectional study of school children, which included histamine challenge for AHR and skin testing for dust mite atopy, we made repeated measurements of HDM allergens in children with a history of wheeze over a 12-month period. These children also kept a daily asthma diary in which they recorded their peak expiratory flow rates (PEFRs). We used a repeated measures model to determine the association between PEFR and HDM allergen concentration.

RESULTS

There was a significant association between PEFRs and HDM allergen concentration (beta-coefficient = -14.17, P = .0024) in children with HDM atopy. An association was not found in children without HDM atopy.

CONCLUSIONS

These findings support the hypothesis that HDM allergens have an adverse effect on the lung function of children with wheeze and highlight the importance of maintaining low dust mite allergen levels throughout the year in the home environment of children sensitized to HDMs.