Early polysensitization is associated with allergic multimorbidity in PARIS birth cohort infants

International audienceBACKGROUND:Profiles of allergic sensitization are poorly documented in infancy. Relations between early sensitization and allergic morbidity need to be clarified.METHODS:This study dealt with children involved in the Pollution and Asthma Risk: an Infant Study (PARIS), a population-based prospective birth cohort. Allergic sensitization to twelve food and four inhalant allergens was assessed at 18 months and defined by a specific immunoglobulin E (IgE) level ≥0.35 kUA /l. Health data were collected by standardized questionnaires at 2 and 6 years. Early allergic profiles were identified by an unsupervised cluster analysis based on health data at 2 years and IgE measurements. Profiles were compared with regard to allergic morbidity and multimorbidity at 6 years.RESULTS:Sensitization to any allergen concerned 13.6% of infants. By cluster analysis, 1525 infants were grouped into three profiles: 89.2% not or rarely sensitized (only 3.7% of sensitized), 9.2% mainly sensitized to one or few allergens (45.2% of monosensitized and 45.9% of paucisensitized) and 1.6% all polysensitized. The prevalence of doctor-diagnosed asthma, rhinitis, eczema, food allergy and multimorbidity at 2 years increased from profile one to profile three (p-trend