310 - Comparing the Association of a Complex Hospital Course in RSV and Influenza Bronchiolitis

Poster Number: 310
Publication Number: 310.213

Katherine M. Tang, The Children's Hospital at Montefiore, New York, NY, United States; Patricia Hametz, The Children's Hospital at Montefiore, Bronx, NY, United States; William Southern, Montefiore Medical Center, Briarcliff Manor, NY, United States

Background: Bronchiolitis is the most common cause of hospital admissions in young children and is caused by a virus. However, it is not known if the specific viral etiology predicts the severity of the clinical syndrome when comparing influenza and respiratory syncytial virus (RSV).

Objective: To compare the association of a complex hospital course between influenza and RSV bronchiolitis admissions.

Design/Methods: A retrospective cohort study was performed on admissions of children less than 2 years who were admitted to a tertiary care children’s hospital from 2016-2019 for bronchiolitis and tested positive for either influenza or RSV. Children who were not tested or had a complex chronic condition were excluded. The primary outcome, complex hospital course, was a composite including intensive care unit admission, respiratory support beyond low flow oxygen, nutritional support by nasogastric tube, prolonged length of stay (≥75th percentile), and death. Secondary outcomes included 7-day readmission and time to respiratory support. Results were analyzed using multivariable logistic regression and competing risks time to event analysis. All adjusted regressions included age, sex, race/ethnicity, and gestational age as covariates.

Results: In total, 1,228 admissions were included with 1,094 (89%) diagnosed with RSV and 134 (11%) diagnosed with influenza. Admissions for RSV tended to be younger (165 days [IQR 62, 359] vs. 336 days [IQR 177, 541]; P< 0.001) and weighed less but the cohorts were similar in sex, gestational age, race/ethnicity, and insurance type (Table 1). Influenza admissions were more likely to be tachycardic for age (84.3% vs 73.5%, P< 0.01), febrile (27.6% vs 18.9%, P=0.02), and receive an antibiotic that treats pneumonia (23.1% vs. 13.1%, P< 0.01). RSV admissions were more likely to receive albuterol (29.6% vs. 14.9%, P< 0.001) (Table 1). Admissions with RSV were significantly more likely to experience a complex hospital course in unadjusted and adjusted analyses (ORunadj= 3.44, 95% CI: 2.23-5.32) (Table 2). In addition, RSV admissions were associated with a significantly higher rate of respiratory support compared to influenza (HRunadj=3.23, 95% CI: 2.02-5.18; HRadj=3.11, 95% CI: 1.93, 5.01) (Figure 1). There was no difference in readmissions.Conclusion(s): In admissions for bronchiolitis of children less than 2 years old, those infected with RSV had higher odds of a complex hospital course and required higher rates of respiratory support compared to those infected with influenza. This information can be utilized in evaluating hospital resources and provide caregivers with anticipatory guidance.
Katherine Tang CVKatherine Tang CV.pdf
Table 2. Primary and secondary outcomes of a complex hospital course and its components based on viral infection.Influenza was used as the reference for all odds ratio calculations.
Abbreviations: RSV, respiratory syncytial virus; 95% CI, 95% Confidence Interval; LOS, length of stay; PICU, pediatric intensive care unit