Risk factors for severe respiratory syncytial virus-associated lower respiratory tract infection in children

Background : Respiratory syncytial virus (RSV) is the most important cause of viral lower respiratory tract infection that can be a life‐threatening disease in infants and children. This study was conducted to look for independent risk factors for severe respiratory syncytial virus‐associated lower respiratory tract infection (RSV‐LRI) that required oxygen supplementation or mechanical ventilation. Methods : Medical records of patients younger than 4 years hospitalized with RSV‐LRI at Shizuoka Red Cross Hospital from July 1, 1995 to June 30, 1999 were reviewed. The patients were compared using univariate and multivariate logistic regression analysis. Results : A total of 157 patients were hospitalized with RSV‐LRI at Shizuoka Red Cross Hospital from the study time period. Of these, 20 patients (12.7%) were diagnosed with severe RSV‐LRI. Subjects younger than 3 months of age had an odds ratio (OR) of 59.9 (95% confidence interval (CI) 14.7_244.0) for the dependent variable of severe RSV‐LRI (P