Half Century Since SIDS: A Reappraisal of Terminology

Child Fatality Review

Understanding why children die is necessary to implement strategies to prevent future deaths and improve the health of any community. Child fatality review teams (CFRTs) have existed since the 1970s and provide a necessary framework to ensure that proper questions are asked about a child's death. CFRTs provide a vital function in a community to ensure that preventable causes of deaths are identified. Pediatricians are necessary members of CFRTs because they provide medical expertise and context around a child's death. All CFRTs should have pediatric physician representation, and results from team meetings should inform public policy at all levels of government. Pediatricians should be supported in their efforts to be present on CFRTs, and they should use data from team meetings to help advocate for implementing prevention strategies.

What More Can We Do to Prevent Infants From Dying While They Sleep?

Sleep-related infant deaths, now called sudden unexpected infant deaths, are not declining, and the United States continues to have greater rates than most other developed nations. Health disparities are significant, with death rates greater in certain vulnerable groups, including non-Hispanic Black infants. Nurses play a crucial role in educating, role-modeling, and problem-solving with parents. Thus, it is critical for nurses to stay current with the science, prevention recommendations, and societal decisions and debates surrounding this topic. This article provides a summary of the updated safe sleep recommendations released by the American Academy of Pediatrics in 2022 as well as discussions on current trends, thoughts, and controversies related to how safe sleep education is provided to parents.

Unexplained and Unexpected Pediatric Deaths: Forensic Review and New Perspectives

Unexplained and unexpected pediatric deaths are a major challenge in global healthcare. The role of the forensic pathologist is crucial in determining the cause and manner of death in these cases, although to date, there are many limitations in post-mortem diagnosis. The role of the autopsy and related forensic investigations become a fundamental tool to investigate and give an explanation for an unacceptable event, considering the young age of the victims. From this point of view, even today, it is necessary that this phenomenon is correctly recorded through standardized systems and universally accepted methods. Furthermore, it is essential that scientific research on this topic is increased through the implementation of universally accepted operating protocols recognizing real risk factors in order to prevent such events. The purpose of the study is to offer a review of the state of the art about unexplained pediatric death and, above all, to propose an international reporting platform, extending proper investigations not only to judicial cases but also to all the other cases of unexpected pediatric death.

Current SIDS research: time to resolve conflicting research hypotheses and collaborate

From the earliest publications on cot death or sudden infant death syndrome (SIDS) through to this day, clinical pathology and epidemiology have strongly featured infection as a constant association. Despite mounting evidence of the role of viruses and common toxigenic bacteria in the pathogenesis of SIDS, a growing school of thought featuring a paradigm based on the triple risk hypothesis that encompasses vulnerability through deranged homoeostatic control of arousal and/or cardiorespiratory function has become the mainstream view and now dominates SIDS research. The mainstream hypothesis rarely acknowledges the role of infection despite its notional potential role as a cofactor in the triple hit idea. Decades of mainstream research that has focussed on central nervous system homoeostatic mechanisms of arousal, cardiorespiratory control and abnormal neurotransmission has not been able to provide consistent answers to the SIDS enigma. This paper examines the disparity between these two schools of thought and calls for a collaborative approach. IMPACT: The popular research hypothesis explaining sudden infant death syndrome features the triple risk hypothesis with central nervous system homoeostatic mechanisms controlling arousal and cardiorespiratory function. Intense investigation has not yielded convincing results. There is a necessity to consider other plausible hypotheses (e.g., common bacterial toxin hypothesis). The review scrutinises the triple risk hypothesis and CNS control of cardiorespiratory function and arousal and reveals its flaws. Infection-based hypotheses with their strong SIDS risk factor associations are reviewed in a new context.

#sleepingbaby on Instagram: Nonadherence of images to safe sleeping advice and implications for prevention of Sudden Unexpected Death in Infancy

OBJECTIVES

Safe sleep of infants is important to reduce the risk of Sudden Unexpected Death in Infancy (SUDI). The depiction of infant care behavior which is inconsistent with the safe sleep recommendations on social media has an impact on parental infant care thoughts, norms and behaviors. This study aims to determine the adherence of Instagram images to the Dutch safe sleeping advice.

DESIGN

A systematic social media analysis on Instagram was performed using 22 hashtags and 9 accounts of Dutch companies or platforms related to infants. Images of sleeping infants were analyzed on consistency with the criteria: supine sleeping position, own cot or crib, sleep sack, and an empty bed.

RESULTS

Based on 514 collected images, 5.9% was consistent with sleep sack use, 16.8% with an empty bed, 30.7% with an own cot or crib, and 67.5% with the supine sleeping position. For 311 images (60.5%), all four criteria could be rated, as for the others, at least one criterion was not clearly depicted. Only 6 of these images (1.9%) were consistent with all four criteria.

CONCLUSIONS

Although Instagram images are probably not representative of regular infant care behavior, the exposure to these images that are mostly inconsistent with the safe sleep advice can contribute to the formation of norms, and therefore influence parental care behavior. Accurate communication of the safe sleep recommendations through social media is needed, and opportunities are described for preventive health professionals to engage more in this communication with their public.

Sudden Unexpected Infant Deaths: 2015-2020

OBJECTIVE

Although the US infant mortality rate reached a record low in 2020, the sudden infant death syndrome (SIDS) rate increased from 2019. To understand if the increase was related to changing death certification practices or the coronavirus disease 2019 (COVID-19) pandemic, we examined sudden unexpected infant death (SUID) rates as a group, by cause, and by race and ethnicity.

METHODS

We estimated SUID rates during 2015 to 2020 using US period-linked birth and death data. SUID included SIDS, unknown cause, and accidental suffocation and strangulation in bed. We examined changes in rates from 2019 to 2020 and assessed linear trends during prepandemic (2015-2019) using weighted least squares regression. We also assessed race and ethnicity trends and quantified COVID-19-related SUID.

RESULTS

Although the SIDS rate increased significantly from 2019 to 2020 (P < .001), the overall SUID rate did not (P = .24). The increased SIDS rate followed a declining linear trend in SIDS during 2015 to 2019 (P < .001). Other SUID causes did not change significantly. Our race and ethnicity analysis showed SUID rates increased significantly for non-Hispanic Black infants from 2019 to 2020, widening the disparities between these two groups during 2017 to 2019. In 2020, <10 of the 3328 SUID had a COVID-19 code.

CONCLUSIONS

Diagnositic shifting likely explained the increased SIDS rate in 2020. Why the SUID rate increased for non-Hispanic Black infants is unknown, but warrants continued monitoring. Interventions are needed to address persistent racial and ethnic disparities in SUID.

The psychological consequences of Sudden Infant Death Syndrome (SIDS) for the family system: A systematic review

The Sudden Infant Death Syndrome (SIDS) is a tragic and difficult experience for families. It involves not only the death of the baby but also the loss of a future as a parent, sibling or grandparent. The subsequent grief is multifaceted and each family member has different needs and resources. Through a systematic review of literature, we identified 24 studies between 1982 and 2021: they dealt with individual, family and couple experience when a SIDS occurs; in addition, some studies compared perinatal loss and neonatal loss with SIDS loss. Our results point out the need for an intervention that focuses on the needs of each family member and tailored around the specifics of SIDS loss rather than general grief.

SIDS is associated with prenatal drug use: a meta-analysis and systematic review of 4 238 685 infants

OBJECTIVE

To conduct a meta-analysis to determine the association between prenatal drug exposure and risk of sudden infant death syndrome (SIDS).

DESIGN

Studies were searched using PubMed, Medline and Embase and restricted to English, with no publication date limit. Selected studies included published cohort, population or case studies comparing the incidence of SIDS among drug-exposed with drug-free controls. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines. Data were pooled using a random-effects model to evaluate risk ratios (RR).

SETTING

High-income countries.

PATIENTS

Children with a history of prenatal drug exposure.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

RR of SIDS between drug-exposed and control infants.

RESULTS

Sixteen studies (36 730 infants with any prenatal drug exposure, 21 661 exposed to opioids, 21 571 exposed to cocaine, 5031 exposed to methadone compared with 4 201 955 with no exposure). Any prenatal drug exposure was associated with an increased crude risk of SIDS (RR 7.84, 95% CI 5.21 to 11.81). Prenatal opioid exposure had the highest associative crude risk of SIDS (RR 9.76, 95% CI 5.28 to 18.05), followed by methadone (RR 9.52, 95% CI 4.60 to 19.70) and cocaine (RR 4.40, 95% CI 2.52 to 7.67). Increased crude risk persisted after adjusting for socioeconomic factors (RR 4.24, 95% CI 1.39 to 12.88). The incidence of SIDS for this cohort decreased between 1972 and 2020 but remained significantly higher than controls.

CONCLUSION

Exposure to any drug of dependency during pregnancy is associated with an increased risk of SIDS after controlling for socioeconomic factors. Further study to evaluate mechanisms and contribution of other confounders (eg, smoking) is warranted.

Rapid Eye Movement Sleep during Early Life: A Comprehensive Narrative Review

The ontogenetic sleep hypothesis suggested that rapid eye movement (REM) sleep is ontogenetically primitive. Namely, REM sleep plays an imperative role in the maturation of the central nervous system. In coincidence with a rapidly developing brain during the early period of life, a remarkably large amount of REM sleep has been identified in numerous behavioral and polysomnographic studies across species. The abundant REM sleep appears to serve to optimize a cerebral state suitable for homeostasis and inherent neuronal activities favorable to brain maturation, ranging from neuronal differentiation, migration, and myelination to synaptic formation and elimination. Progressively more studies in Mammalia have provided the underlying mechanisms involved in some REM sleep-related disorders (e.g., narcolepsy, autism, attention deficit hyperactivity disorder (ADHD)). We summarize the remarkable alterations of polysomnographic, behavioral, and physiological characteristics in humans and Mammalia. Through a comprehensive review, we offer a hybrid of animal and human findings, demonstrating that early-life REM sleep disturbances constitute a common feature of many neurodevelopmental disorders. Our review may assist and promote investigations of the underlying mechanisms, functions, and neurodevelopmental diseases involved in REM sleep during early life.

Evidence Base for 2022 Updated Recommendations for a Safe Infant Sleeping Environment to Reduce the Risk of Sleep-Related Infant Deaths

Every year in the United States, approximately 3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Statistical Classification of Diseases and Related Health Problems 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths have remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. In addition, additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, which is included in this issue.

Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment

Each year in the United States, ∼3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Classification of Diseases, 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths has remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. Additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is also included. The recommendations and strength of evidence for each recommendation are included in this policy statement. The rationale for these recommendations is discussed in detail in the accompanying technical report.

Barriers to consistent and reliable investigation of sudden unexpected infant death: Perspectives from law enforcement

Despite persistent efforts to advance infant death investigation, most sudden unexpected infant deaths (SUIDs) remain unexplained. Law enforcement officials contribute to SUID investigations throughout the United States, but their impacts on these investigations have not been adequately examined. In this exploratory study, 26 law enforcement officials were interviewed about their experiences and perspectives with SUID investigations. Thematic analysis of qualitative data revealed three specific difficulties law enforcement encounter during SUID investigations: (1) inadequate preparation; (2) overwhelming emotions; and (3) a victim-suspect dilemma. Findings indicate that these barriers may inhibit consistent and reliable investigation of infant death and, therefore, may impede the cause and manner of death determinations. Participants' narratives also offered insights into potential solutions, including expanded SUID training for law enforcement and use of checklists, such as the Sudden Unexpected Infant Death Investigation Reporting Form. The impacts of overwhelming emotions confronted during SUID investigation warrant further study. The victim-suspect dilemma stems from the inability of law enforcement to conclusively eliminate the possibility of homicide. This dilemma may be resolved through a clear distinction between interactions with potential evidence and interactions with the family. Law enforcement must be trained to treat all SUID families in a compassionate and non-accusatory manner, while investigating all SUID with careful attention to detail that is essential in any potential homicide investigation. A consistent, meticulous, and compassionate approach to SUID investigations will improve the reliability of information obtained and offer the best opportunity for providing answers to grieving parents.

Epidemiology of sudden infant death syndrome in Mexico, 2005-2020

BACKGROUND

Sudden Infant Death Syndrome (SIDS) constitutes one of the main causes of mortality in children under one year of age in developed countries; it's frequency to varies geographically. In Mexico the real incidence of SIDS is not known.

METHODS

National databases of deaths in children under one year of age, from 2005 to 2020, were analyzed, due to Sudden Unexpected Infant Death (SUID) [SIDS (R95), accidental suffocation in a sleeping environment (W75), and other ill-defined and unspecified causes of mortality (R99), according to the International Classification of Diseases, tenth revision (ICD 10)]. Mortality rates per year of occurrence due to SUID and their subcategories were calculated. Simple frequencies of SIDS were obtained per year and month of occurrence, state of residence, age, place of death, and access to social security services.

RESULTS

In the study period 473,545 infant deaths occurred; 7,714 (1.62%) deaths were due to SUID; of these, 6,489 (84%) were due to SIDS, which is among the 10 leading causes of infant death in Mexico. The average mortality rate for SUID was 22.4/100,000 live births, for SIDS was 18.8/100,000 live births. Mortality rates within the states were variable, ranging from 2.4/100,000 to 105.1/100,000 live births. In 81% of SIDS records there was no autopsy; 38% of deaths due to SIDS occurred in infants under one month of age, up to 87% of deaths occurred in families without social security services or it was unknown, and 76.2% of deaths occurred at home. Deaths were more frequent during the last months of autumn and during winter.

CONCLUSION

In Mexico there is an underregistry of SIDS as cause of death, along with other SUID categories. Health workers need to be trained to improve diagnosis and data registration, including the practice of autopsies; additionally, it is necessary to implement a public health campaign.

Renewed Attention Needed for Prevention of Sudden Unexpected Death in Infancy in the Netherlands

Background: The incidence of sudden unexpected death in infancy (SUDI), which includes sudden infant death syndrome (SIDS), has declined in developed countries since the 1980s, including the Netherlands. To identify improvement opportunities in SUDI prevention, we monitored the adherence of parents to the prevention advice on infant care habits over the past 20 years, especially in relation to the SUDI incidence over time. Potential changes in parental adherence between the latest surveys are of specific interest, as these indicate where current focus is needed. Methods: Description of the prevalence of infant care factors related to the risk of SUDI, assessed from five Dutch national surveys from 1999 to 2017 among parents of infants under 12 months, and analysis of the potential differences in these prevalences between the two latest surveys in 2010/11 and 2017 with a z-test. Results: Supine sleeping position decreased from the highest prevalence of 92% in 2010/11, to 83% in 2017. Sleep sack use has increased to 55%, the highest prevalence up to now. Avoiding a duvet has remained reasonably stable since 2002/03 and now 95% of parents do not use a duvet. The prevalence of room-sharing, without sharing the bed, increased from 14% in 1999 to the highest prevalence in 2017 (31%). However, also bed-sharing almost doubled from 5.6% in 2010/11 to 10% in 2017. Breastfeeding decreased between 1999 and 2010/11, but increased from 34% in 2010/11 to 42% in 2017. An increased prevalence of mothers who abstained from smoking during pregnancy, as well as both parents not smoking, was observed, although mostly higher educated parents showed this beneficial behavior. Discussion and Conclusion: Much has already been achieved first by decreasing prone sleeping since the 80's, and subsequently promoting supine as the safest sleep position. The decrease in duvet use and smoking, and an increase in breastfeeding have also had impact. Indications of a recent decreased prevalence of the supine sleeping position and higher prevalence of bed-sharing might relate to the slightly increasing SUDI incidence in the Netherlands. Renewed attention for prevention of SUDI and specific advice targeting high-risk groups is needed. Modern, picture driven information via internet is recommended.

Risk and Preventive Factors for SUDI: Need We Adjust the Current Prevention Advice in a Low-Incidence Country

Background: The incidence of Sudden Unexpected Death in Infancy (SUDI) is low in the Netherlands, with an incidence rate of 0.18 per 1,000 live births. Therefore, prevention advice may receive less attention, potentially leading to increasing incidence rates. It is currently unknown whether the risks for SUDI changed in the Netherlands, and if other risk factors might be present. The aim of this study was to examine the current risks and preventive factors for SUDI in Dutch infants, in order to determine if it is necessary to adapt the prevention advice toward the current needs. Methods: A case-control study was conducted comparing SUDI cases aged <12 months from 2014-2020 in the Netherlands (n = 47), to a Dutch national survey control group from 2017 including infants <12 months of age (n = 1,192). Results: Elevated risks for several well-known factors were observed, namely: duvet use (aOR = 8.6), mother smoked during pregnancy (aOR = 9.7), or after pregnancy (aOR = 5.4) and the prone sleeping position (aOR = 4.6). Reduced risks were observed for the well-known factors: room-sharing (aOR = 0.3), sleep sack use (aOR = 0.3), breastfeeding (aOR = 0.3), and the use of a pacifier (aOR = 0.4). For infants <4 months, the risk for SUDI was higher when bed-sharing (aOR = 3.3), and lower when room-sharing (aOR = 0.2) compared to older infants. For older infants, the sleep sack was found to be more protective (aOR = 0.2). A high risk for SUDI when bed-sharing was found when mother smoked, smoked during pregnancy, or if the infant did not receive any breastfeeding (respectively aOR = 17.7, aOR = 10.8, aOR = 9.2). Conclusions: Internationally known factors related to the sudden unexpected death of infants were also found in this study. Relatively new findings are related to specific groups of infants, in which the strengths of these risk factors differed. In a low-incidence country like the Netherlands, renewed attention to the current prevention advice is needed. Furthermore, additional attention for prevention measures in low educated groups, and additional advice specifically targeting high-risk groups is recommended.