Allergic diseases and asthma in the family predict the persistence and onset-age of asthma: a prospective cohort study.

Background: Family history of asthma and other allergic diseases have been linked to the risk of childhood asthma previously, but little is known about their effect on the age-of-onset and persistency of asthma until young adulthood.

Methods: We assessed the effect of the family history of asthma and allergic diseases on persistent vs. transient, and early- vs.