Introduction
Sudden infant death syndrome (SIDS) rates have declined significantly in the United States (US) as a result of the “Back to Sleep” campaign. Despite this and many state and local risk reduction campaigns, rates still remain high in the African American and American Indian/Alaska Native populations. The American Academy of Pediatrics (AAP) recently released (2016) updated guidelines and recommendations for a safe sleep environment (12). However, certain recommendations, especially the advice against infant bed sharing, continue to be controversial and are not followed by some groups. Further research on the reasons for non-adherence and identification of culturally acceptable and safe alternatives that address parental concerns are needed to help in targeting educational interventions in high-risk populations. In this chapter, we will address SIDS from a US perspective, covering rates and trends, interventions to reduce risk, the bed-sharing controversy, and current laws and regulations in the US.
SIDS Rates in the US
Sudden unexpected infant death (SUID), also known as sudden unexpected death in infancy (SUDI), is defined as the sudden and unexpected death of an infant regardless of cause (1). The largest proportion of SUID deaths among all racial/ethnic groups is attributed to sudden infant death syndrome (SIDS). SIDS, a subset of SUID, is defined as “the sudden and unexpected death of an infant under 12 months of age that remains unexplained after a review of the clinical history, complete autopsy and death scene investigation” (1) (p. 681). In 2014, there were approximately 3,500 SUID deaths in the US, and 44% of them (1,500 deaths) were attributed to SIDS (2). Despite continued efforts to promote safe sleep, the SIDS mortality rates in the US have plateaued.
Trends
In 1994, in response to studies from Europe and Australia, the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) initiated the “Back to Sleep” campaign to help educate millions of caregivers in the US on ways to reduce the risk of SIDS (3). The campaign promoted placing babies on their back to sleep. In 2012, the NICHD expanded the campaign to emphasize safe sleep environments and back sleeping as ways to reduce SIDS and other sleep-related deaths, renaming it the “Safe to Sleep” campaign. In the years following the initial campaign, SIDS rates decreased by 50% in the US (3). This decline was consistent with the decline in prone sleeping (4). However, despite ongoing efforts to promote safe sleep, recent declines in SIDS mortality rates have been smaller, and, as of 2014, the SIDS mortality rate is 39 deaths per 100,000 live births (5).
Racial/ethnic disparities
SUID and SIDS mortality rates, like other infant mortality causes, have substantial racial and ethnic disparities (3). For example, the SUID death rates in the US from 2010-13 were 190.5 deaths per 100,000 live births for American Indian/Alaska Natives and 171.8 deaths per 100,000 live births for non-Hispanic black infants, which were more than two times those for non-Hispanic white infants (84.4 deaths per 100,000 live births) (6). The mortality rate due to SIDS was 83% higher (73.3 deaths per 100,000 live births) in non-Hispanic black infants and 95% higher (78.3 deaths per 100,000 live births) in American Indian/Alaskan Native infants compared to non-Hispanic white infants (40.1 deaths per 100,000 live births) (7). This may in part be explained by the difference in prevalence of supine sleep position and other sleep environments among the different racial and ethnic groups (8). The National Infant Sleep Position Study (NISP) found that the prevalence of supine positioning was 53% among black infants, 73% among Hispanic infants, and 75% among white infants (4, 8). Similarly, bed sharing and the use of soft bedding were also more common among black families (3, 9, 10). A recent study showed that there is an overall increasing trend in the number of infants who usually share a bed or other sleep surface (11). The same study found that black infants are 3.5 times more likely to share a bed than white infants (11), and that this trend is increasing for black infants while remaining unchanged among white infants.
Recommendations for a Safe Infant Sleep Environment, Controversies and Barriers to Adherence
Recommendations
The AAP Task Force on SIDS recently released its updated 2016 recommendations for a safe sleep environment () (12). The guidelines include supine sleep for every sleep; using a firm sleep surface; room sharing without bed sharing; and avoiding soft bedding and overheating. Additional recommendations include using a pacifier; avoiding smoke exposure, alcohol and illicit drug use; breastfeeding; obtaining regular prenatal care; and receiving routine immunizations (12).
Summary of 2016 AAP Safe Sleep Recommendations. (Based on the recommendations of the AAP and adapted from Table 2 in (12).).
Common controversies
There has been considerable controversy in the US regarding the AAP recommendations advising against parent-infant bed sharing. The epidemiologic evidence supports this recommendation (13). Adult beds are not designed for infant safety, and often contain other bedding materials, such as pillows and comforters, which may increase the risk of SIDS as well as death due to other causes, including asphyxia and suffocation, and unintentional injuries, such as falls. There is growing concern among public health and SIDS program professionals about bed sharing because of the rising number of deaths attributed to accidental strangulation and suffocation in bed (14). Nonetheless, bed sharing is common; up to 60% of mothers of infants reported bed sharing at least once within the infant’s first year of life (15). In a national survey of mothers of infants under 8 months of age, 14% reported routinely bed sharing in the prior two weeks (3).
There are many reasons given by mothers for sleeping with their infants, including facilitating feeding (breastfeeding or formula), comforting a fussy or sick infant, helping with sleep for mother and infant, bonding, cultural tradition, and feeling that babies are safest when close to their mother. Some breastfeeding advocacy groups encourage bed sharing to promote breastfeeding, including longer duration and exclusivity (3). They argue that bed sharing is safe among infants who are breastfed (a protective factor for SIDS) and infants whose mothers do not smoke, drink alcohol, or use illicit substances. However, this issue is still being debated; two recent analyses (from studies outside the US) reached different conclusions and recommendations (see Chapter 10) (3, 16, 17).
The new AAP guidelines recognize that mothers often fall asleep while nursing their infants, and that it is safer to fall asleep while nursing in bed than on a couch, sofa, or armchair (12). It is recommended that mothers return their infants to their own sleep surface once they awaken. It is also recommended that bedding that could cause head covering or airway obstruction should be removed from the adult bed.
Barriers to adherence
The barriers determining infant sleeping practices are complex and often involve behavioral, environmental, and biological factors. Most parents base their decisions about sleep location on their perception of the infant’s comfort and convenience for the parent. However, a large study of African American mothers in Washington, DC found that they had different views about what they considered comfortable (18). Some thought that infants who slept longer were most comfortable while others thought the surface should not be too thin or too hard. Many mothers also had different definitions for what was considered a “firm” sleep surface, with some believing that a taut surface equaled a firm surface, so it would be acceptable to place pillows or blankets on top of a taut sheet (18). Parents may also opt to bed share in order to monitor the infant more closely or breastfeed and bond with the infant (19, 20).
Some of the socioeconomic and environmental factors discussed by these mothers for bed sharing involved not having space to put a crib, not having money to buy a crib, or worrying about dangers from insects, kidnappings, or stray gunfire (20). Other reasons for not adhering to the recommended safe sleep practices included not trusting the guidelines due to the inconsistencies in the recommendations over the years, as well as observing the practices and behaviors of their healthcare providers, who did not endorse or model safe sleep guidelines (19, 21). In another study that included African American and American Indian mothers in Michigan, similar barriers were identified, including concerns for infant safety and the perception that an infant placed in the supine position will choke, despite evidence against this (19, 22).
Further discussion with these two cohorts of mothers examined their beliefs and behaviors related to SIDS and safe sleep (19, 22). The investigators found that regardless of socioeconomic backgrounds, there were three major themes that explained their beliefs regarding SIDS: [1] lack of plausibility (not understanding how recommendations to reduce the risk of SIDS could be defined for an entity that has an “unknown cause”; [2] randomness (“God’s will”); and [3] parental vigilance (the belief that as long as the parent was near the infant, SIDS would not happen) (19, 22). Many of the mothers did not see the usefulness of following safe sleep practices unless they could be guaranteed that SIDS would not occur if they followed the guidelines.
Results from these studies suggest that education about safe sleep recommendations needs to go hand in hand with detailed explanations about the reasons behind the recommendations and more definitive descriptions about our understanding of SIDS causation (18-22). In addition, the meaning of terms that are used in the recommendations, such as “firm sleep surface”, needs to be better explained, and mothers should be asked by healthcare providers about their understanding of the recommendations, to allow clarification if any misunderstandings exist.
Interventions to Reduce the Risk of SIDS
Healthcare providers play an important role in modeling AAP recommendations and influencing parents and caregivers on safe sleep behaviors (23). Unfortunately, a recent study showed that more than half of healthcare providers are inconsistent with modeling safe sleep practices in the hospital and teaching safe sleep recommendations to parents (24). There have been multiple interventions implemented to reduce the risk of SIDS by encouraging parents to follow safe sleep guidelines. A recent systematic review of safe sleep interventions internationally from 1990-2015 found 29 studies that met the inclusion criteria, 22 of which were based in the US (25). Of the 29 studies, 19 targeted families and infant caregivers, 8 targeted healthcare professionals, and 2 targeted childcare professionals. Some of the more commonly targeted behaviors for the interventions included SIDS knowledge, sleep location, and infant sleep position. Out of the 8 US studies measuring SIDS knowledge, 7 of them found significant differences in knowledge while 1 found no significant difference after the intervention (25). Of the 10 US studies that measured sleep location (use of crib in the parents’ room), only 3 of them reported that their interventions were successful in increasing the rates of using a crib (25). Of the 14 US studies, 7 that measured infant sleep position concluded that their interventions were successful in changing the rates of, or intention to use, supine sleep position (25); 6 found no significant differences, while 1 study reported increased rates of supine sleep position, but did not report statistical significance (25). However, a recent study conducted in Ohio that was not included in the systematic review found that by implementing a statewide quality improvement collaborative and providing Maintenance of Certification (MOC) Part IV participation (part of the process required for US physicians to retain specialty board certification), they were able to show an improvement in infant safe sleep practices across their six children’s hospitals (23).
There are many national, statewide and local efforts to educate mothers and nurses on safe sleep. A recent review discussed several safe sleep interventions and examined evidence of their effectiveness (26). Interventions that focused on health messaging include a public health campaign in 2009 on safe sleep in the city of Baltimore, Maryland, called ‘B’more for Healthy Babies’ (BHB). Up until then, Baltimore had one of the highest infant mortality rates in the US (27). The city created a video, with testimonials from three Baltimore parents who lost their infants while bed sharing, called “SLEEP SAFE: Alone, Back, Crib. No Exceptions”. The video is shown to all mothers while they are in the hospital, in addition to other sites including the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) sites, city detention centers, Department of Social Services, and jury duty locations (26). BHB’s SLEEP SAFE initiative includes media campaigns, community outreach, and provider education. In addition to declining infant mortality rates, Baltimore has also seen a 40% decrease in the racial disparities between African American and white infants from 2009-12 (27).
One of the more provocative health messaging campaigns regarding safe sleep came from the Milwaukee, Wisconsin’s Department of Health. The city had 89 infant deaths related to SIDS or SUID, and, of those, 52% were bed sharing at the time of their death (28). In response to these statistics, Milwaukee public health officials developed a campaign that used extreme fear-invoking messages to generate attention. Much like the anti-smoking campaigns that show images of diseased lungs, the city in 2010 showed a photograph of a tombstone instead of a headboard at the top of an adult bed, with the phrase “For too many babies last year, this was their final resting place”. In 2011, another ad of an infant sleeping in an adult bed next to a butcher’s knife with the slogan “Your baby sleeping with you can be just as dangerous” was posted. No formal evaluation of this campaign was conducted; however, the Department of Health reported that the requests for free cribs increased in the years following the campaign (26, 28).
Other interventions focus on breaking down barriers and increasing accessibility. The Cribs for Kids National Infant Safe Sleep Initiative is a national coalition of non-profit organizations that provide free cribs to low-income families that may not be able to afford one. The program also provides education on safe sleep to parents and caregivers. The Women, Infants and Children (WIC) programs in several states also provide books, brochures, and vouchers with safe sleep messages (29). One study surveyed a sample of crib recipients in Pennsylvania and found that 38% of infants would have slept in the same bed as an adult had they not received a crib (30). Bedtime Basics for Babies was another program that provided free cribs and safe sleep education to high-risk families in Washington, DC, Indiana, and Washington state (31). Eligible families received a portable crib, a crib sheet, a wearable blanket, a pacifier, and safe sleep education. Families also watched an informational video on safe sleep and were asked to participate in a survey before and after crib receipt. Knowledge of recommended infant sleep position improved from 76% to 94% (p<0.001), and intended use of supine position also increased from 80% to 87% (p<0.001) after receipt of the intervention (31). The study found that crib distribution and safe sleep education together successfully changed the participants’ knowledge about safe sleep and the placement of infants on their backs in their own crib for sleep (31).
There continues to be resistance to safe sleep guidelines among professionals; therefore, interventions have been developed that focus on the education of healthcare professionals (26). Cribs for Kids supports a Safe Sleep Hospital Initiative, which is a “hospital certification program awarding recognition to hospitals that demonstrate a commitment to community leadership for best practices and education on infant sleep safety” (32). The program was developed in 2008 and aims to reduce the risk of injury and death to infants while sleeping. The program’s goal is to provide accurate and consistent safe sleep information to all hospital personnel, enable hospitals to model safe sleep practices, and provide consistent and repeated safe sleep information to parents and caregivers (33).
Breastfeeding is recommended to reduce the risk of SIDS. The Baby Friendly Hospital Initiative is an international program that was launched by the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF). The initiative recognizes hospitals that offer the best possible care for infant feeding and mother-infant bonding. The program is a comprehensive model including education, policy change, and training of all hospital personnel using tools such as the Ten Steps to Successful Breastfeeding (34). Currently, there are more than 450 US hospitals and birthing centers in all 50 states, the District of Columbia and the Commonwealth of Puerto Rico that are designated as Baby-Friendly facilities (34).
Laws and Regulations
Many states have laws related to SIDS and protocols for autopsies of SIDS cases. At least 12 states have laws requiring firefighters, emergency medical technicians, law enforcement officials, or childcare workers to take special training on SIDS (35). Studies have estimated that 20% of SIDS deaths in the US occur in childcare settings where they have been placed prone to sleep (36, 37). Approximately 17 states have required SIDS risk reduction education for all childcare providers; however, these regulations are only applicable to licensed childcare centers and not to family childcare homes, which are difficult to identify (26).
In addition to legislation and regulations around childcare professionals, a recent area of focus has been around the use of crib bumpers. Maryland’s Department of Health and Mental Hygiene (DHMH) and the city of Chicago, Illinois have laws that ban the sale of crib bumpers. Crib bumpers, which are designed to wrap around the crib slats, were initially developed to prevent entrapment of an infant’s head between the slats of the crib. However, crib standards now require the width between the slats to be less than 2 3/8” (approximately 6 cm), which removed the need for crib bumpers (3). Crib bumpers have been implicated in deaths attributed to suffocation, strangulation, and entrapment (38). The Maryland DHMH and the city of Chicago concluded that the crib bumpers offer no benefit and pose a risk of suffocation and death. The recent AAP guidelines also state that they do not recommend the use of crib bumpers because of the potential for suffocation, entrapment, and strangulation (3).
There are other commercially available products on the market today, such as special mattresses, sleep devices, sleep surfaces, wedges, and positioners, which are labeled as protective against the risk of SIDS. However, they are often made of soft, compressible material which may increase the risk of suffocation (3). Furthermore, there is no scientific evidence to back up these claims. Due to the lack of scientific evidence and the potential risk of suffocation, entrapment, and strangulation with these products, the AAP, along with the Consumer Product Safety Commission (CPSC) and the Food and Drug Administration (FDA), warns against their use, unless they meet CPSC safety standards — for example, in the case of special crib mattresses or sleep surfaces (3).
Conclusions
Deaths from SIDS in the US have declined by over 50% as a result of national guidelines and campaigns, as well as many other interventions at the state and local levels. However, certain recommendations, especially the advice against infant bed sharing, continue to be controversial and are not followed by certain groups within the population. Research is needed to further understand the reasons for non-adherence to recommendations and to identify, where possible, culturally acceptable, safe alternatives and prudent policies.
Acknowledgements
Ms Tanabe and Dr Hauck are grateful to their families for their support and encouragement, and to the SIDS community for their tireless work on behalf of infants and families.
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