Factors associated with progression to severe condition and treatment prolongation in respiratory syncytial virus infection: a retrospective study in Japan

Abstract

Overview Background: In recent years, the epidemic of respiratory syncytial virus (RSV) has been seen in the summer. In daily clinical practice, we noted that RSV infection tends to become more severe and its treatment tends to be longer, particularly in patients hospitalized in the summer. Thus, we investigated factors associated with the progression to severe condition and the prolongation of treatment in RSV infection. Methods: Subjects were pediatric patients diagnosed with RSV infection and hospitalized for treatment during the 5 year s from April 2014 to March 2019. Information on age, sex, season of hospitalization, gestational age, and bronchial asthma of each subject was collected from inpatient medical records. Duration of oxygen administration was used as an index for treatment duration and the use of devices for severe cases as an index for severity. Multiple linear regression analysis and logistic regression analysis were performed to examine the variables associated with duration of oxygen administration and use of a device for severe cases. Results: Data from 298 patients were analyzed. Duration of oxygen administration was significantly associated with bronchial asthma (partial regression coefficient: 0.804, p = 0.010). Hospitalization in summer was significantly associated with use of a device for severe condition (adjusted odds ratio: 5.89, 95% confidence interval: 1.72-20.18). Conclusion: The present study showed that bronchial asthma is a risk factor for prolongation of treatment and infection in summer is a risk factor for progression to severe condition in cases of RSV infection. These findings suggested that children with bronchial asthma and infection in summer need to be treated carefully regardless of their age, sex, and gestational age.