Few data exist on associations between childhood adiposity and incident asthma in later life. The present authors examined the relationship between childhood body mass index (BMI) and incident asthma beginning in adolescence or in adult life. All subjects included in the study were participants in the Tasmanian Asthma Survey, a large population-based cohort study, and were asthma free at 7 yrs of age. Weight, height and lung function were measured at 7 yrs of age. Asthma status at 7 and 32 yrs of age was ascertained by questionnaire. Odds ratios were calculated for the association between childhood adiposity, expressed as "overweight" or as BMI z-score quartiles at 7 yrs of age, and asthma development after that age. In females, but not in males, there was a significant association between adiposity at 7 yrs of age and current asthma at 32 yrs of age that developed after the age of 21 yrs. The association was not explained by childhood lung function or age at menarche. There was no association between adiposity at 7 yrs of age and asthma that developed after that age and remitted at 32 yrs of age in either sex. Higher body mass index in nonasthmatic young females at 7 yrs of age predicts risk of current asthma developing in adult life.
