Hallas HW, et al. - Investigators assessed 411 children from the at-risk COPSAC₂₀₀₀ birth cohort born to mothers with asthma to examine if low lung function and bronchial hyperreactivity are inherent features that increase the risk of developing airway inflammation and asthmatic symptoms. They observed that children who developed asthma had decreased lung function from 1 month of age throughout childhood as vs children without asthma. This lung function characteristic was evident prior to the development of airway inflammation and asthma, and did not worsen with prolonged duration of asthma symptoms. Findings, therefore, suggested that airway obstruction and bronchial hyperreactivity may be stable traits of childhood asthma, indicating that symptomatic disease may be a result of these traits but not their cause.