The Relationship between the Time of First Respiratory Syncytial Virus Bronchiolitis and Later Wheezing and Asthma Development

Abstract

Purpose : Respiratory syncytial virus(RSV) bronchiolitis is believed to be associated with later development of asthma and wheezing. This study was conducted to determine the relationship between the age of the first RSV bronchiolitis episode, the development of later wheezing and asthma, and the related other factors. Methods : We studied 255 infants admitted with their first episode of RSV bronchiolitis. Epidemiological and clinical data were collected retrospectively from medical records and through telephone interviews. The patients were divided into ≤3 months, 4 to 12 months, and 13 to 24 months. Results : Eighty-one infants were ≤3 months, 115 were 4 to 12 months, and 59 were 13 to 24 months old. The gender ratios (Male:Female) were 1:1, 1.6:1, and 3.2:1. Familial and personal history of allergic diseases and disease severity did not significantly differ according to the age of the first RSV bronchiolitis episode. The occurrence of wheezing was associated with the presence of a familial and personal history of allergic diseases, but not with gender (male) or disease severity. The risk for asthma increased when the infants had their first RSV bronchiolitis episode at an older age. A personal history of allergic diseases was associated with an increased risk for asthma. Conclusion : Asthma was more frequently diagnosed in older infants. The most important risk factors for recurrent wheezing and asthma were a familial and personal history of allergic diseases. Therefore, it was thought that RSV bronchiolitis is not the cause of recurrent wheezing and asthma, but that infants with a genetic predisposition to asthma have an increased risk for RSV bronchiolitis. [Pediatr Allergy Respir Dis(Korea) 2012;22:54-63]