Risk factors for hospitalized respiratory syncytial virus disease and its severe outcomes

INTRODUCTION: Respiratory syncytial virus (RSV) is a major cause of hospital admission for acute lower respiratory tract infection in young children. OBJECTIVES: We aimed to identify risk factors for hospitalized RSV disease and its severe outcomes. METHODS: We conducted a retrospective cohort study analyzing data of a ICD-10-code-based hospital surveillance for severe acute respiratory infections (SARI). Using univariable and multivariable logistic regression analysis, we assessed age-group, gender, season, and underlying medical conditions as possible risk factors for RSV and its severe outcomes including ICU admission, application of ventilator support, and death, respectively. RESULTS: Of the 413 552 patients hospitalized with SARI in the database, 8761 were diagnosed with RSV from week 01/2009 to 20/2018 with 97% (8521) aged <5 years. Among children aged <5 years, age-groups 0-5 months (OR: 20.29, 95% CI: 18.37-22.41) and 6 months-1 year (OR: 4.59, 95% CI: 4.16-5.06), and underlying respiratory and cardiovascular disorders specific to the perinatal period (OR: 1.32, 95% CI: 1.11-1.57) were risk factors for being diagnosed with RSV. Age-group 0-5 months (OR: 2.39, 95% CI: 1.45-3.94), low birth weight (OR: 6.77, 95% CI: 1.28-35.71), preterm newborn (OR: 6.71, 95% CI: 2.19-20.61), underlying respiratory and cardiovascular disorders specific to the perinatal period (OR: 4.97, 95% CI: 3.36-7.34), congenital malformation of the heart (OR: 3.65, 95% CI: 1.90-7.02), congenital malformation of the great vessels (OR: 3.50, 95% CI: 1.10-11.18), congenital defect originating in perinatal period (OR: 4.07, 95% CI: 1.71-9.70), cardiovascular disease (OR: 5.19, 95% CI: 2.77-9.72), neurological disorders (OR: 6.48, 95% CI: 3.76-11.18), blood disease (OR: 3.67, 95% CI: 1.98-6.79), and liver disease (OR: 14.99, 95% CI: 1.49-150.82) contributed to ICU admission in RSV cases. CONCLUSIONS: Using ICD-10-based surveillance data allows to identify risk factors for hospitalized RSV disease and its severe outcomes, and quantify the risk in different age-groups.