Severe bronchiolitis profiles and risk of asthma development in Finnish children

International audience ; Background: Recent studies support the existence of several entities under the clinical diagnosis of "bronchiolitis". Among infants with severe bronchiolitis, distinct profiles have been differentially associated with development of recurrent wheezing by age 3 years. However, their associations with actual asthma remain unclear.Objectives: To study the association between severe bronchiolitis profiles identified by a clustering approach and childhood asthma.Methods: Among 408 children (age <2 years) hospitalized with bronchiolitis in Finland (2008-2010), latent class analysis identified three bronchiolitis profiles: profile A (47%), characterized by history of wheezing/eczema, wheezing during acute illness and rhinovirus infection; profile BC (38%), characterized by severe illness and RSV infection; and profile D (15%), the least severely ill group including mostly children without wheezing and with rhinovirus infection. Children were followed by questionnaire 4 years later (86%, n=348) and through a nationwide social insurance database 7 years later (99%, n=403). Current asthma at 4- and 7-year follow-ups was defined by regular use (parental report and medical records) or purchase (social insurance database) of asthma control medication.Results: Compared with profile BC, we observed increased risk of current asthma associated with profile A both at 4-year follow-up (age- and sex-adjusted odds ratio, 2.42; 95%CI: 1.23-4.75) and at 7-year follow-up (3.14; 1.33-7.42). No significant difference in asthma risk was observed between profile D and profile BC.Conclusion: These longitudinal results provide further support for an association between a distinct severe bronchiolitis profile (characterized by history of wheezing/eczema and rhinovirus infection) and risk of developing childhood asthma.