Hospital Readmissions Among Children With H1N1 Influenza Infection

Objectives: To describe readmissions among children hospitalized with H1N1 (influenza subtype, hemagglutinin1, neuraminidase 1) pandemic influenza and secondarily to determine the association of oseltamivir during index hospitalization with readmission.

Methods: We reviewed data from 42 freestanding children's hospitals contributing to the Pediatric Health Information System from May through December 2009 when H1N1 was the predominant influenza strain. Children were divided into 2 groups by whether they experienced complications of influenza during index hospitalization. Primary outcome was readmission at 3, 7, and 30 days among both patient groups. Secondary outcome was the association of oseltamivir treatment with readmission.

Results: The study included 8899 children; 6162 patients had uncomplicated index hospitalization, of whom 3808 (61.8%) received oseltamivir during hospitalization, and 2737 children had complicated influenza, of whom 1055 (38.5%) received oseltamivir. Median 3-, 7-, and 30-day readmission rates were 1.6%, 2.5%, and 4.7% for patients with uncomplicated index hospitalizations and 4.3%, 5.8%, and 10.3% among patients with complicated influenza. The 30-day readmission rates did not differ by treatment group among patients with uncomplicated influenza; however, patients with complicated index hospitalizations who received oseltamivir had lower all-cause 30-day readmissions than untreated patients. The most common causes of readmission were pneumonia and asthma exacerbations.

Conclusions: Oseltamivir use for hospitalized children did not decrease 30-day readmission rates in children after uncomplicated index hospitalization but was associated with a lower 30-day readmission rate among children with complicated infections during the 2009 H1N1 pandemic. Readmission rates for children who had complicated influenza infection during index hospitalizations are high.