Wheeze phenotypes in young children have different courses during the preschool period.

Background: Rules for predicting the course of asthma in wheezy infants have low specificity.

Objective: To determine if the novel phenotypes-mild early viral wheeze (EVW), atopic multiple-trigger wheeze (MTW), and nonatopic uncontrolled wheeze (NAUW)-have different courses during the preschool period.

Methods: Part of the prospectively followed Trousseau Asthma Program cohort was phenotyped using cluster analysis with 12 parameters (sex, asthma severity and control with inhaled corticosteroid [ICS], parental asthma, allergic rhinitis, eczema, food allergy, EVW or MTW, and allergen exposure trigger).