Symptoms suggestive of atopic rhinitis in children aged 6-9 years and the indoor environment.

Background: We aimed to investigate the influence of indoor factors on the prevalence of symptoms suggestive of atopic rhinitis in children aged 6-9 years in Upper Austria.

Methods: We analyzed the results from an extended ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire, answered by the parents, about indoor environment and symptoms strongly suggesting atopic rhinitis. This was defined as having reported a running, obstructed, or itchy nose apart from having a cold in the last year. The overall response rate was 93.4%. After excluding 6,016 children (17.1%) with changed indoor environment (due to allergies in the family), we analyzed the remaining subsample of 18,606 questionnaires.

Results: The following factors were associated with an increased risk: mother's smoking during pregnancy and/or during time of breast-feeding (OR 1.28; CI 1.07-1.52), synthetic bedding (OR 1.21; CI 1.09-1.36), dampness/mold at home (OR 1.51; CI 1.31-1.74), central heating with gas (OR 1.75; CI 1.06-2.87), and space heating (OR 1.66; CI 1.01-2.98). Cooking with wood (OR 0.62; CI 0.46-0.84) was negatively associated with symptoms.

Conclusions: The indoor environment plays a role in the symptoms of atopic rhinitis in children. However, the population-attributable risks were not particularly high; they were between -2.7% and 9% for the various exposures considered in this study.