Abstract
Background: Parental asthma has been linked to personal asthma previously, but the effects of heredity on the persistence and onset-age of asthma until young adulthood need further studies.
Objectives: We investigated the influence of heredity on transient vs. persistent and early-onset vs. late-onset asthma in the Espoo Cohort Study 20-year follow-up of 1623 people (63.2% of the baseline).
Methods: Asthmatics (n = 220) were divided into persistent asthma according to symptoms and/or medication in the follow-ups after the initial diagnosis of asthma and transient if otherwise. Persistent asthma was divided into early- and late-onset asthma using the age of 13 years as cut-point. The determinants were any heredity (any parent or sibling); maternal; paternal; both parents; siblings only; parents only and both siblings and parents. Adjusted risk ratios (RRa) were calculated with Poisson regression and Q-statistics to calculate heterogeneity between RRs.
Results: Heredity influenced all the subtypes but in various ways. Most hereditary determinants had a stronger impact on persistent asthma than transient, but siblings only had a similar impact on both (persistent: RRa = 2.16, 95% CI = 1.27-3.68; transient: RRa = 2.10, 95% CI = 1.15-3.86; heterogeneity P = 0.95). Maternal asthma seemed to effect only early-onset asthma (RRa = 2.75, 95% CI = 1.62-4.69) while the impact of paternal asthma continued (early: RRa = 2.28, 95% CI = 1.15-4.53; late: RRa = 1.98, 95% CI = 0.76-5.15; heterogeneity P = 0.81).
Conclusions: Heredity plays the most important role in persistent and early-onset asthma. The impact of paternal asthma continues to young adulthood while the influence of maternal asthma decreases with age.
- © 2014 ERS
