Do Pacifiers Reduce the Risk of Sudden Infant Death Syndrome? A Meta-analysis

Objective. Pacifier use has been re- ported to be associated with a reduced risk of sudden infant death syndrome (SIDS), but most countries around the world, including the United States, have been reluctant to recommend the use of pacifiers because of concerns about possible adverse effects. This meta-anal- ysis was undertaken to quantify and evaluate the protec- tive effect of pacifiers against SIDS and to make a rec- ommendation on the use of pacifiers to prevent SIDS. Methods. We searched the Medline database (January 1966 to May 2004) to collect data on pacifier use and its association with SIDS, morbidity, or other adverse ef- fects. The search strategy included published articles in English with the Medical Subject Headings terms "sud- den infant death syndrome" and "pacifier" and the key- words "dummy" and "soother." Combining searches re- sulted in 384 abstracts, which were all read and evaluated for inclusion. For the meta-analysis, articles with data on the relationship between pacifier use and SIDS risk were limited to published original case-control studies, be- cause no prospective observational reports were found; 9 articles met these criteria. Two independent reviewers evaluated each study on the basis of the 6 criteria devel- oped by the American Academy of Pediatrics Task Force on Infant Positioning and SIDS; in cases of disagree- ment, a third reviewer evaluated the study, and a consen- sus opinion was reached. We developed a script to cal- culate the summary odds ratio (SOR) by using the reported ORs and respective confidence intervals (CI) to weight the ORs. We then pooled them together to com- pute the SOR. We performed the Breslow-Day test for homogeneity of ORs, Cochran-Mantel-Haenszel test for the null hypothesis of no effect (OR 1), and the Mantel- Haenszel common OR estimate. The consistency of find- ings was evaluated and the overall potential benefits of pacifier use were weighed against the potential risks. Our recommendation is based on the taxonomy of the 5-point (A-E) scale adopted by the US Preventive Ser- vices Task Force. Results. Seven studies were included in the meta- analysis. The SOR calculated for usual pacifier use (with univariate ORs) is 0.90 (95% confidence interval (CI): 0.79-1.03) and 0.71 (95% CI: 0.59-0.85) with multivariate ORs. For pacifier use during last sleep, the SORs calcu- lated using univariate and multivariate ORs are 0.47 (95% CI: 0.40-0.55) and 0.39 (95% CI: 0.31-0.50), respectively. Conclusions. Published case-control studies demon- strate a significant reduced risk of SIDS with pacifier use, particularly when placed for sleep. Encouraging pac- ifier use is likely to be beneficial on a population-wide basis: 1 SIDS death could be prevented for every 2733 (95% CI: 2416-3334) infants who use a pacifier when placed for sleep (number needed to treat), based on the US SIDS rate and the last-sleep multivariate SOR result- ing from this analysis. Therefore, we recommend that pac- ifiers be offered to infants as a potential method to reduce the risk of SIDS. The pacifier should be offered to the infant when being placed for all sleep episodes, including daytime naps and nighttime sleeps. This is a US Preventive Services Task Force level B strength of recommendation based on the consistency of findings and the likelihood that the beneficial effects will outweigh any potential negative effects. In consideration of potential adverse effects, we recommend pacifier use for infants up to 1 year of age, which includes the peak ages for SIDS risk and the period in which the infant's need for sucking is highest. For breastfed infants, pacifiers should be introduced after breastfeeding has been well established. Pediatrics 2005; 116:e716-e723. URL: www.pediatrics.org/cgi/doi/10.1542/ peds.2004-2631; pacifiers, SIDS, risk factors, risk reduc- tion, meta-analytic methods.