Incidence of asthma diagnosis and self-reported allergy in relation to theschool environment - a four-year follow-up study in schoolchildren

SETTING: In schools, the indoor air quality is often poor and there is grow ing concern about its impact on the pupils' health. OBJECTIVE: To study the incidence of asthma diagnosis and self-reported all ergy in schoolchildren in relation to the school environment. DESIGN: Data on asthma and allergies were collected through a postal questionnaire answe red in 1993 and 1997 by 1347 (78%) pupils (initially aged 7-13 years) in 39 randomly chosen schools. Indoor pollutants were measured in about 100 clas srooms in 1993 and 1995. Relationships between indoor pollutants and incide nce of asthma diagnosis and self-reported allergy were studied by multiple logistic regression, adjusting for age, sex, atopy and smoking. RESULTS: The incidence of asthma diagnosis was higher in pupils attending s chools with more settled dust and more cat allergen (Fel d 1) in this dust. Incidence of self-reported furry pet allergy was higher in schools with mo re respirable particles. Among children without a history of atopy, a new a sthma diagnosis was more common at higher concentrations of formaldehyde an d total moulds in the classroom air. CONCLUSION: A school environment with more dust, cat allergen, formaldehyde and moulds may affect the incidence of asthma and sensitivity to furry pet s in schoolchildren.