Lee E, et al. - In this longitudinal analysis of elementary school children from the Children's HEalth and Environmental Research (CHEER) study, a 4-year prospective follow-up study with 2-year intervals starting at a mean age of 7 years, researchers classified bronchial hyperresponsiveness (BHR) phenotypes according to onset age and persistence in children and studied the features and factors related to each phenotype. They reported high atopic burden and increased risk of newly diagnosed asthma in relation to early-onset persistent BHR phenotype in school-aged children. They also found the association of late-onset BHR phenotype with later sensitization and AR symptoms. Targeted follow-ups are needed for diverse BHR phenotypes in children having specific characteristics.