We thank the letter writers for their comments about our latest report and agree that it is unfortunate that the press has chosen to concentrate so heavily on the bed-sharing and pacifier risk factors and far less on the other 9 recommendations for reducing the risk of sudden infant death syndrome (SIDS). Placing infants to sleep on their backs is still the strategy most convincingly linked to reduced risk. Nevertheless, bed sharing and nonuse of pacifiers have emerged as consistent risk factors that we felt must be called to the attention of the public and medical communities. We will group our responses into several categories.
BEDSHARING AND THE POSSIBILITY OF RECOMMENDING THAT IT CAN BE DONE SAFELY
Drs Eidelman, Gartner, Gessner, and Porter believe that studies linking bed sharing and SIDS have not specifically examined the subsets of the population, such as breastfeeders, and therefore the recommendation should be aimed at teaching parents how to bed share safely. The most recent evidence linking the risk of SIDS with bed sharing is particularly strong when parents smoke or when they sleep with an infant on a couch, sofa, or armchair. Consumption of alcohol or use of sedating medications may also increase the risk. However, the risk is still increased when nonsmoking parents bed share with infants in adult beds1,2 even when the infants are breastfed.2 Demonstrating safety (ie, no risk) is usually far more difficult than demonstrating risk because of the statistical challenge of collecting sufficient numbers in a subgroup to permit avoidance of a type 2 statistical error. Breastfeeding mothers who do not smoke, have not consumed consciousness-depressing substances, and are not “overtired” while bed sharing constitute such a subgroup. The task force felt that there was insufficient evidence to recommend safe bed sharing and that the evidence for a protective effect of room sharing was sufficiently strong to recommend this strategy. We know of no studies examining SIDS risk when the infant is sleeping in a separate room equipped with a monitoring device, as suggested by Pelayo et al. Individual parents and physicians may interpret these data differently and choose to bed share while avoiding other known risk factors, but we believe that the data justify a general recommendation for separate but proximate sleeping. We also recognize that cultural traditions may make it difficult for some families to embrace all of the recommendations. Health professionals who educate families about potential risks and advise about ways to reduce those risks need to be sensitive to parents' experiences and concerns. This contextual approach to counseling families is likely to lead to more successful implementation of all the risk-reduction guidelines. We also agree with Drs Eidelman and Gartner that it is our responsibility as health care professionals and epidemiologists to educate law-enforcement agencies of the inappropriateness of citing parents for child abuse on the basis of population-based risk analysis.
There are many cultures for which bed sharing is the norm and SIDS rates are low. However, the bed sharing practiced in those cultures is generally very different from that in the United States (eg, with firm mats on the floor, separate mats for the infant, and/or absence of soft bedding). It has not yet been determined what constitutes “safe” bed sharing. In the United States, approximately half of the infants that die from sudden, unexpected death do so while sleeping with their parents.3–5 Although the reasons for the protective effect of room sharing without bed sharing are not fully known, it is likely that when the infant is in a crib or bassinet next to the parents' bed, it allows for maternal-infant sensory exchanges and increased infant arousals, similar to those that would be present during bed sharing. In addition, room sharing allows for easy access to the infant for breastfeeding. We too believe that breastfeeding and parent-infant bonding are extremely important, but bed sharing is not imperative for success of either or both. We encourage parents to interact, cuddle, and bond with their infants during awake times.
WEAKNESS OF THE CASE-CONTROL PACIFIER STUDIES AND THE POSSIBILITY THAT NONUSE BY HABITUATED PACIFIER USERS MAY ACTUALLY INCREASE THE RISK OF SIDS
All of the epidemiologic data about SIDS risk factors, including those describing the relationship to sleep position, have necessarily come from case-control studies; these types of studies were also the source of the supine-sleep recommendation, which has proven to be extremely effective in reducing the incidence of SIDS. It is highly unlikely that any randomized, controlled studies examining any of the SIDS risk factors will ever be performed. Since publication of Dr Hauck's analysis,6 another study (from Germany) has been published that shows the same protective effect of pacifiers when used during last sleep.7 The “most compelling data” to which Dr Bartick refers, we assume, is one study that found an increased risk of SIDS associated with the absence of a pacifier at last sleep among habitual users.8 This finding has not been reported by others following multivariate analysis. The overwhelming weight of evidence indicates a strong reduced risk for use of pacifiers at last sleep independent of change in pacifier use for last sleep. Nonetheless, the task force recognizes the need to carefully follow trends and outcomes to ensure that the recommendation does not lead to unforeseen harm.
MECHANISM OF SIDS AND THE RELATIONSHIP TO SLEEP
The most current information regarding the etiology of SIDS indicates that, at least for some of these deaths, there is a developmental abnormality in the serotonergic network in the brainstem, which results in the failure to arouse or respond to life-threatening stressors such as asphyxia and hypercapnia when asleep.9,10 Furthermore, physiologic studies demonstrate that infants who sleep supine have decreased sleep duration, decreased non-REM sleep, and increased arousals11; this effect peaks at 2 to 3 months of age and is not evident at 5 to 6 months of age,12 thus coinciding with the peak incidence for SIDS at 2 to 4 months of age. The SIDS risk-reduction strategy of supine sleep will result in a lower arousal threshold and a reduction in quiet sleep. Back to Sleep campaigns have been in place in many countries since the early 1990s, and there has been no indication that supine sleep has lasting negative effects on infant growth and development. Although supine sleepers are more likely to attain certain gross motor milestones later than prone sleepers, this delay is within normal limits and is no longer apparent at 1 year of age.13–15 In addition, these differences in motor development are not apparent when awake “tummy time” is used.16,17 There have been no other reports that reduced quiet sleep and lower arousal threshold have had a detrimental effect on infant growth and development. The reason for the protective effect of pacifiers is unclear; however, lower arousal thresholds may play a role. Although there is no indication that introducing pacifiers at sleeptime will negatively affect growth and development, we agree with Pelayo et al that the effects of this recommendation should be monitored closely.
ISSUES RELATED TO TIMING OF PUBLICATION, CITATION OF AN ABSTRACT, CONFLICTS OF INTEREST, AND CONSULTATION WITH OTHER BRANCHES OF THE AMERICAN ACADEMY OF PEDIATRICS
Although the pacifier meta-analysis6 was published in the same issue as the task force statement, there are no new individual study data reported in the meta-analysis. All the pacifier studies had been published over the past 12 years and thus have been readily available for critique by the professional community. The abstracted study referred to by Dr Bartick was intentionally not included in the meta-analysis because it had not been published yet in a peer-reviewed journal. The confirmatory results were mentioned in the discussion, which is not an uncommon practice. One of the task force members is an author of that article and knew that the study was under review; it has since been published in the British Medical Journal.18 In regard to the conflict-of-interest assertion, FirstCandle is a nonprofit philanthropic organization that provides support to parents who have lost an infant to SIDS, educates the public about SIDS risk, and raises funds for investigators to conduct studies of infant mortality. Its medical advisors are unpaid and donate their time to advise the organization on medical issues, as do the volunteer task forces and committee members of the American Academy of Pediatrics. To imply that the volunteers somehow benefit financially from this relationship is absurd. Finally, all American Academy of Pediatrics task force and committee statements must go through a rigorous 2- to 3-year process that involves Executive Board approval of the plan to prepare a statement, development of drafts substantiated by published research, submission of drafts to other committees and sections, and final approval by the Executive Board. The current statement was subjected to each step of this process, including 3 submissions to the Section on Breastfeeding, with responses returned to the section and revisions made by the task force after each response. Although the Section on Breastfeeding was not in agreement with some aspects of the final draft, the Executive Committee was in receipt of all comments and determined the final wording. The task force recommendation about pacifier use is consistent with the Section on Breastfeeding's recent policy statement: “Pacifier use is best avoided during the initiation of breastfeeding and used only after breastfeeding is well established.… This recommendation does not contraindicate pacifier use for nonnutritive sucking and oral training of premature infants and other special care infants.”19
- ↵Carroll-Pankhurst C. Sudden infant death syndrome, bedsharing, parental weight, and age at death. Pediatrics.2001;107 :530– 536
- Unger B, Kemp JS, Wilkins D, et al. Racial disparity and modifiable risk factors among infants dying suddenly and unexpectedly. Pediatrics.2003;111(2) . Available at: www.pediatrics.org/cgi/content/full/111/2/e127
- ↵Hauck FR, Omojokun OO, Siadaty MS. Do pacifiers reduce the risk of sudden infant death syndrome? A meta-analysis. Pediatrics.2005;116(5) . Available at: www.pediatrics.org/cgi/content/full/116/5/e716
- ↵McGarvey C, McDonnell M, Chong A, O'Regan M, Matthews T. Factors relating to the infant's last sleep environment in sudden infant death syndrome in the Republic of Ireland. Arch Dis Child.2003;88 :1058– 1064
- ↵Kahn A, Groswasser J, Sottiaux M, Rebuffat E, Franco P, Dramaix M. Prone or supine body position and sleep characteristics in infants. Pediatrics.1993;91 :1112– 1115
- ↵Dewey C, Fleming P, Golding J. Does the supine sleeping position have any adverse effects on the child? II. Development in the first 18 months. ALSPAC Study Team. Pediatrics.1998;101(1) . Available at: www.pediatrics.org/cgi/content/full/101/1/e5
- ↵Davis BE, Moon RY, Sachs HC, Ottolini MC. Effects of sleep position on infant motor development. Pediatrics.1998;102 :1135– 1140
- ↵Li DK, Willinger M, Petitti DB, Odouli R, Liu L, Hoffman HJ. Use of a dummy (pacifier) during sleep and risk of sudden infant death syndrome (SIDS): population based case-control study. BMJ.2006;332 :18– 22
- ↵Gartner LM, Morton J, Lawrence RA, et al. Breastfeeding and the use of human milk. Pediatrics.2005;115 :496– 506
- Copyright © 2006 by the American Academy of Pediatrics