Increased adiposity associated with increased length of stay for infants with bronchiolitis

OBJECTIVES: Excess adiposity upregulates proinflammatory adipokines in infancy that have also been implicated in the pathogenesis of bronchiolitis. The association between excess adiposity and severity of disease in bronchiolitis is unclear. We sought to examine the association between adiposity and length of hospitalization and risk of PICU transfer in children with bronchiolitis. METHODS: We conducted a retrospective cohort study examining infants 24 months and younger hospitalized at an academic children's hospital with bronchiolitis, grouped by weight status (BMI z score and ponderal index). Data were extracted from the medical record, including the following relevant covariates: Age, sex, race and/or ethnicity, and International Classification of Diseases, 10th Revision codes. Outcomes included length of stay (LOS) and PICU transfer. We used multiple regression to examine the association between each anthropometric measure and LOS and likelihood of PICU transfer. RESULTS: There were 765 children in the final sample, 599 without a significant comorbidity (eg, prematurity, congenital heart disease). The median LOS was 2.8 days (interquartile range 1.7-4.9 days). LOS increased with increasing ponderal index quartile (P 5 .001). After accounting for age and significant comorbidities, we used multivariable regression to identify a significant association between increasing ponderal index and LOS (P 5 .04) and no association between BMI and LOS. Logistic regression did not reveal an association between either anthropometric measure and PICU transfer. CONCLUSIONS: In this study, we identified an association between a measure of excess adiposity in infants and length of hospitalization for bronchiolitis. Further work is needed to confirm this association, examine potential mechanisms, and account for other potential confounders.