Clinical question: What is the incidence of apnea in infants hospitalized with respiratory syncytial virus (RSV) bronchiolitis?
Background: Apnea is a known and reported complication of RSV infection in infants. In clinical practice, this relationship could be the basis for admission despite a lack of symptoms that would otherwise necessitate hospitalization. The exact nature of this association remains unclear, specifically with respect to incidence and risk factors for apnea.
Study design: Systematic chart review.
Synopsis: A literature search was conducted using a combination of the terms “apnea” (or “apnoea”), “bronchiolitis,” “respiratory syncytial virus” and/or “lower respiratory tract infection.” Studies were included if they reported apnea rates for a consecutive cohort of hospitalized infants. Thirteen studies involving 5,575 patients were reviewed.
Rates of apnea ranged from 1.2% to 23.8%. Infants of younger, postconceptional age (≤44 weeks) and pre-term infants were at greater risk for apnea. Term infants without serious underlying illness appeared to have a <1% risk of apnea, based on the most recent studies.
A consistent finding of this review was the heterogeneity of the data in the included studies. Definitions of apnea varied, were broad, and included subjective criteria. Age stratification was infrequent. Inclusion and exclusion criteria were variable with respect to age cutoffs and relevant comorbidities. Future research will need to carefully delineate all of these potential confounding variables.
Bottom line: While rates of apnea in RSV bronchiolitis are difficult to quantify, there appears to be an association with younger, postconceptional age and pre-term birth.
Citation: Ralston S, Hill V. Incidence of apnea in infants hospitalized with respiratory syncytial virus bronchiolitis: a systematic review. J Pediatr. 2009;155(5):728-733.
Reviewed by Pediatric Editor Mark Shen, MD, medical director of hospital medicine at Dell Children’s Medical Center, Austin, Texas.