Systematic literature review assessing tobacco smoke exposure as a risk factor for serious respiratory syncytial virus disease among infants and young children Full Text
BMC Pediatrics, 06/26/2012

DiFranza JR et al. – The authors found ample evidence that environmental tobacco smoke (ETS) exposure places infants and young children at increased risk of hospitalization for RSV–attributable lower respiratory tract infection and increases the severity of illness among hospitalized children. Additional evidence is needed regarding the association of ETS exposure and outpatient RSV lower respiratory tract illness.

• A systematic review of English-language studies using the PubMed and EMBASE databases (1990-2009) was performed to retrieve studies that evaluated ETS as a potential risk factor for serious RSV illness.
• Studies assessing risk factors associated with hospitalization, emergency department visit, or physician visit due to RSV (based on laboratory confirmation of RSV or clinical diagnosis of RSV) in children under the age of 5years were included.

• The literature search identified 30 relevant articles, categorized by laboratory confirmation of RSV infection (n=14), clinical diagnosis of RSV disease (n=8), and assessment of RSV disease severity (n=8).
• Across these three categories of studies, at least 1 type of ETS exposure was associated with statistically significant increases in risk in multivariate or bivariate analysis, as follows: 12 of 14 studies on risk of hospitalization or ED visit for laboratory-confirmed RSV infection; 6 of 8 studies of RSV disease based on clinical diagnosis; and 5 of the 8 studies assessing severity of RSV as shown by hospitalization rates or degree of hypoxia.
• Also, 7 of the 30 studies focused on populations of premature infants, and the majority (5 studies) found a significant association between ETS exposure and RSV risk in the multivariate or bivariate analyses.