House dust mite allergen reduction and allergy at 4 yr: follow up of the PIAMA-study.

Exposure to high allergen levels in early life is a risk factor for the development of allergy. We previously reported limited effects of mite allergen impermeable mattress covers in the prevention and incidence of asthma and mite allergy (PIAMA) cohort at the age of 1 and 2 yr. We now present the results of follow-up at 4 yr objectives.

Allergen exposure in infancy and the development of sensitization, wheeze, and asthma at 4 years.

Background: The relationship between mite and pet allergen exposure in infancy and the subsequent development of sensitization and asthma is complex.

Objective: We prospectively investigated the effect of allergen exposure at 3 months of age on the development of sensitization, wheeze, and physician-diagnosed asthma in the first 4 years of life in a birth cohort of children with and without an atopic mother.

Methods: Children participated in the Prevention and Incidence of Asthma and Mite Allergy study.

Interrupter resistance and wheezing phenotypes at 4 years of age.

It is difficult to distinguish young children with respiratory symptoms who will develop asthma from those with transient symptoms only. Measurement of interrupter resistance may help to identify children at high risk of asthma. The aim of this study is to compare interrupter resistance in 4-year-old children with different wheezing phenotypes.