Changing prevalence of respiratory symptoms and treatment in Dutch school children: 1989-1997

To investigate whether the prevalence of respiratory symptoms, physicians visits, medication use and school absence in Dutch children changed between 1989 and 1997, and whether respiratory symptoms are related to changed exposure to tobacco smoke and pets.

Parents of children eligible for a routine physical examination in 1989 (3176 children), 1993 (3491 children) or 1997 (4776 children), were asked to complete a questionnaire about respiratory symptoms for their child.

Response rates were almost 100%. Between 1989 and 1997 the prevalence of shortness of breath increased from 7.4% to 9.3% (p=0.056) in 5-6 year olds, whereas the prevalence of wheezing decreased (from 22.1% to 18.3%, p=0.002). The same trend was seen in 8-9 year-old children. The proportion of asthmatic children consulting their physician or using medication increased (from 55.9% to 63.3% and from 38.7% to 47.4%, respectively), whereas cigarette smoking (from 60.8% to 48.5%) and pet ownership (from 55.1% to 47.0%) decreased.

Our findings support other reports of an increasing prevalence of asthma and treatment. However, this could not be explained by increased exposure to cigarette smoke or pets.