Incidence of apnea in infants hospitalized with respiratory syncytial virus bronchiolitis: a systematic review.

OBJECTIVE: To determine the incidence of apnea in infants hospitalized with respiratory syncytial virus (RSV) bronchiolitis and identify relevant risk factors from the available literature.

STUDY DESIGN: A systematic search of available databases for studies reporting the rate of apnea in a consecutive cohort of infants hospitalized with RSV infection was performed. The overall incidence of apnea was extracted and analyzed in relation to preterm birth, age, and potentially confounding illnesses.

RESULTS: The incidence of apnea in the study population of 5575 hospitalized patients with RSV ranged from a high of 23.8% to a low of 1.2%. Comparison of the cohort by term and preterm birth revealed an expected excess in apnea incidence in preterms, even in the absence of information about chronologic age. Many studies appeared to be confounded by the inclusion of impaired infants with neuromuscular disorders.

CONCLUSIONS: Based on the available data, precisely quantifying the risk of apnea attributable to RSV infection is not possible. Factors intrinsic to the individual infants may account for a significant percentage of the apnea attributed to RSV. Recent studies have found a < 1% incidence of apnea with RSV in previously healthy term infants.