Background: Few prospective data link early childhood adiposity with asthma-related symptoms.
Objective: We sought to examine the associations of weight-for-length (WFL) at age 6 months with incidence of wheezing by age 3 years.
Methods: We studied 932 children in a prospective cohort of children. The main outcome was recurrent wheezing, which was defined as parents' report of wheezing between 2 and 3 years of age plus wheezing in either year 1 or 2 of life. Secondary outcomes included any wheezing from 6 months to 3 years and current asthma. We used multiple logistic regression to examine associations of 6-month WFL z scores with these outcomes.
Results: At 6 months, the infants' mean WFL z score was 0.68 (SD, 0.94; range -2.96 to 3.24). By age 3 years, 14% of children had recurrent wheezing. After adjustment for a variety of potential confounders, we found that each 1-unit increment in 6-month WFL z score was associated with greater odds of recurrent wheezing (odds ratio [OR], 1.46; 95% CI, 1.11-1.91) and any wheezing (OR, 1.23; 95% CI, 1.03-1.48). We observed a weaker association between 6-month WFL z score and current asthma (OR, 1.22; 95% CI, 0.94-1.59).
Conclusion: Infants with higher WFL z scores at 6 months of age had a greater risk of recurrent wheezing by age 3 years. It is unclear whether the relationship of infant adiposity and early-life wheeze extends to allergic asthma or wheeze that can persist into later childhood. Our findings suggest that early interventions to prevent excess infant adiposity might help reduce children's risk of asthma-related symptoms.