Hospitalizations in Infants and Young Children With Cystic Fibrosis Enrolled in Medicaid.

Background: There are limited data describing hospitalization rates among infants and young children with CF (cwCF). National administrative claims databases can be used to characterize hospitalizations among cwCF which could inform the future impact of novel therapies increasingly being integrated into routine care for cwCF.

Methods: We performed a retrospective cohort study of the Merative Medicaid Marketscan database from 2010 to 2019 to characterize hospitalizations among cwCF during their first 3 calendar-years of life. Eligible cwCF were identified using International Classification of Diseases 9/10 codes and had a pharmacy fill for pancreatic enzymes. Hospitalizations were categorized as complicated neonatal, respiratory, gastrointestinal, or other types using Diagnosis Related Groups (DRG).

Results: During the study period, 518 (62.7%) of unique cwCF were hospitalized, amounting to an overall hospitalization rate of 70.9 (95% CI: 67.0-75.0) per 100 child-years. In the birth year complicated neonatal DRGs were most common while in the second and third calendar-years respiratory DRGs were most common. In the second calendar-year of life, respiratory syncytial virus (RSV) and influenza were identified in 11.1% and 6.8% of respiratory hospitalizations, respectively.

Conclusions: CwCF experienced a large burden of hospitalizations during their first three calendar-years of life. Respiratory DRGs were most common in the second and third calendar-years and included a substantial proportion of RSV- and influenza-associated hospitalizations. Such data can inform future work assessing the impact of new therapies for CF and RSV.