Inconsistent classification of unexplained sudden deaths in infants and children hinders surveillance, prevention and research: recommendations from The 3rd International Congress on Sudden Infant and Child Death

Evaluation of Concordance Between Original Death Certifications and an Expert Panel Process in the Determination of Sudden Unexplained Death in Childhood

IMPORTANCE

The true incidence of sudden unexplained death in childhood (SUDC), already the fifth leading category of death among toddlers by current US Centers for Disease Control and Prevention estimates, is potentially veiled by the varied certification processes by medicolegal investigative offices across the United States.

OBJECTIVE

To evaluate the frequency of SUDC incidence, understand its epidemiology, and assess the consistency of death certification among medical examiner and coroner offices in the US death investigation system.

DESIGN, SETTING, AND PARTICIPANTS

In this case series, 2 of 13 forensic pathologists (FPs) conducted masked reviews of 100 cases enrolled in the SUDC Registry and Research Collaborative (SUDCRRC). Children who died aged 11 months to 18 years from 36 US states, Canada, and the United Kingdom had been posthumously enrolled in the SUDCRRC by family members from 2014 to 2017. Comprehensive data from medicolegal investigative offices, clinical offices, and family members were reviewed. Data analysis was conducted from December 2014 to June 2020.

MAIN OUTCOMES AND MEASURES

Certified cause of death (COD) characterized as explained (accidental or natural) or unexplained, as determined by SUDCRRC masked review process.

RESULTS

In this study of 100 cases of SUDC (mean [SD] age, 32.1 [31.8] months; 58 [58.0%] boys; 82 [82.0%] White children; 92 [92.0%] from the United States), the original pathologist certified 43 cases (43.0%) as explained COD and 57 (57.0%) as unexplained COD. The SUDCRRC review process led to the following certifications: 16 (16.0%) were explained, 7 (7.0%) were undetermined because of insufficient data, and 77 (77.0%) were unexplained. Experts disagreed with the original COD in 40 cases (40.0%). These data suggest that SUDC incidence is higher than the current Centers for Disease Control and Prevention estimate (ie, 392 deaths in 2018).

CONCLUSIONS AND RELEVANCE

To our knowledge, this is the first comprehensive masked forensic pathology review process of sudden unexpected pediatric deaths, and it suggests that SUDC may often go unrecognized in US death investigations. Some unexpected pediatric deaths may be erroneously attributed to a natural or accidental COD, negatively affecting surveillance, research, public health funding, and medical care of surviving family members. To further address the challenges of accurate and consistent death certification in SUDC, future studies are warranted.

Circumstances and factors of sleep-related sudden infancy deaths in Japan

Background

Sudden unexpected death in infancy (SUDI) comprises both natural and unnatural causes of death. However, few epidemiological surveys have investigated SUDI in Japan.

Objective

This retrospective study was conducted to investigate the latest trends of circumstances and risk factors of SUDI cases in which collapse occurred during sleep.

Methods

Forensic pathology sections from eight universities participated in the selection of subjects from 2013 to 2018. Data obtained from the checklist form were analyzed based on information at postmortem.

Results

There were 259 SUDI cases consisting of 145 male infants and 114 female infants with a mean birth weight of 2888 ± 553 and 2750 ± 370 g, respectively. Deaths most frequently occurred among infants at 1 month of age (18%). According to population data as the control, the odds ratio (95% confidence interval) of mother’s age ≤19 years was 11.1 (6.9–17.7) compared with ages 30–39. The odds ratio for the fourth- and later born infants was 5.2 (3.4–7.9) compared with the frequency of first-born infants. The most frequent time of day for discovery was between 7 and 8 o’clock, and the time difference from the last seen alive was a mean of 4.1 h. Co-sleeping was recorded for 61%, and the prone position was found for 40% of cases at discovery. Mother’s smoking habit exhibited an odds ratio of 4.5 (2.9–5.8).

Conclusion

This study confirmed the trends that have been observed for sudden infant death syndrome; particularly, very high odds ratios were evident for teenage mothers and later birth order in comparison with those in other developed countries. Neglect was suspected in some cases of the prolonged time to discovery of unreactive infants. To our knowledge, this is the first report of an extensive survey of SUDI during sleep in Japan.

International time trends in sudden unexpected infant death, 1969-2012

Background

Sudden unexpected infant death (SUID) - including sudden infant death syndrome (SIDS) - continues to be a major contributor to infant mortality worldwide. Our objective was to analyse time trends and to identify country-clusters.

Methods

The National Statistical Offices of 52 countries provided the number of deaths and live births (1969–2012). We calculated infant mortality rates per 1000 live births for SUID, SIDS, and all-cause mortality. Overall, 29 countries provided sufficient data for time course analyses of SUID. To sensitively model change over time, we smoothed the curves of mortality rates (1980–2010). We performed a hierarchical cluster analysis to identify clusters of time trends for SUID and SIDS, including all-cause infant mortality.

Results

All-cause infant mortality declined from 28.5 to 4.8 per 1000 live births (mean 12.4; 95% confidence interval 12.0–12.9) between 1969 and 2012. The cluster analysis revealed four country-clusters. Clusters 1 and 2 mostly contained countries showing the typical peak of SUID mortality during the 1980s. Cluster 1 had higher SUID mortality compared to cluster 2. All-cause infant mortality was low in both clusters but higher in cluster 1 compared to cluster 2. Clusters 3 and 4 had low rates of SUID without a peak during the 1980s. Cluster 3 had the highest all-cause infant mortality of all clusters. Cluster 4 had an intermediate all-cause infant mortality. The time trends of SUID and SIDS mortality were similar.

Conclusions

The country-specific time trends in SUID varied considerably. The identification of country-clusters may promote research into how changes in sleep position, smoking, immunisation, or other factors are related to our findings.

Hippocampal abnormalities and seizures: a 16-year single center review of sudden unexpected death in childhood, sudden unexpected death in epilepsy and SIDS

Sudden Unexpected Death in Childhood (SUDC) is the unexplained death of children aged between 1 and 18 years old. Hippocampal abnormalities have previously been described in Sudden Unexpected Death in Epilepsy (SUDEP) and it is possible that SUDC shares similar pathogenic mechanisms with SUDEP. Our aim was to determine the prevalence of hippocampal abnormalities, history of seizures and demographic features in our caseload of SUDC, SUDEP and SIDS cases. A review of post-mortem reports from 2003 to 2018 was carried out to identify cases of SUDC, SUDEP and SIDS. Histological evidence of hippocampal abnormalities, patient demographics (age, gender), sleeping position, and past medical history (history of seizures and illness 72 hours prior to death) were recorded. Statistical analysis was performed to compare the three groups. 48 SUDC, 18 SUDEP and 358 SIDS cases were identified. Hippocampal abnormalities associated with temporal lobe epilepsy were found in 44.4% of SUDC cases. 5/15 SUDC cases with a history of seizures demonstrated hippocampal abnormalities. SUDC cases were also more likely to be found prone compared to SIDS cases. In comparison with SIDS, both SUDC and SUDEP cases were more likely to demonstrate hippocampal abnormalities (SUDC: (OR = 9.4, 95% CI: 3.1-29.1, p < 0.001; SUDEP: OR = 35.4, 95% CI: 8.3-151.5, p < 0.001). We found a potential link between hippocampal abnormalities and epileptic seizures in SUDC. A concerted effort should be directed towards consistent sampling and standardized description of the hippocampus and clinical correlation with a history of seizures/epilepsy in postmortem reports.

The multiagency approach to Sudden Unexpected Infant Deaths (SUID): eleven years' experience in the Tuscany Region

Background

The Sudden Unexpected Infant Death Syndrome (SUID) is one of the leading causes of mortality in the first year of life. The aim of this work was the retrospective evaluation of the incidence of SUID and the effectiveness of the multiagency approach to this phenomenon in the Tuscany Region.

Methods

Data were obtained from the regional registry of SUID cases in the period 2009–2019. The registry contains both sudden unexpected deaths in the first week of life (Sudden Unexpected Early Neonatal Deaths - SUEND), and those occurring after the first week up to 1 year of age (SUID).

Results

In this timeframe a total of 73 sudden unexpected deaths occurred in our region; 32 were Unexplained (i.e. Sudden Infant Death Syndrome - SIDS), 24 Explained, 10 Undetermined, and 7 SUEND. Autopsies were performed in 91% of cases, and in 95% of these by three groups of selected pathologists according to our protocol.

We found a low incidence of SUID (0.21 ‰), and SIDS deaths accounted for 0.1‰ of live births (48% of cases) with a high prevalence of infants of non-Italian ethnicity (38% of cases). Bereaved families were able to receive psychological support from mental health professionals and have contact with the family association, Seeds for SIDS. Audits were organized when post-mortem examinations were not carried out or carried out incorrectly in procedural terms, and when the diagnosis was particularly uncertain.

Conclusions

This paper first provides data on SUID mortality based on complete post-mortems in an Italian region. According to these findings we can state that our approach is effective both in terms of correctly performed autopsies and support for bereaved families. Future efforts are necessary to further reduce the incidence of SUID especially among non- Italian infants. An improvement action is also recommended for ensuring a more accurate and consistent picture of the circumstances of death.

The final approval of the National Protocol for the management of SUID cases is therefore strongly advocated in order to improve surveillance in this specific field and abolish disparities among the Italian regions.

A de novo BRPF1 variant in a case of Sudden Unexplained Death in Childhood

Sudden Unexplained Death in Childhood (SUDC), the death of a child that remains unexplained after a complete autopsy and investigation, is a rare and poorly understood entity. This case report describes a 3-year-old boy with history of language delay and ptosis, who died suddenly in his sleep without known cause. A pathogenic de novo frameshift mutation in BRPF1, a gene which has been associated with the syndrome of Intellectual Developmental Disorder with Dysmorphic Facies and Ptosis (IDDDFP), was identified during a post-mortem evaluation. The finding of a pathogenic variant in BRPF1, which has not previously been associated with sudden death, in an SUDC case has implications for this child's family and contributes to the broader field of SUDC research. This case demonstrates the utility of post-mortem genetic testing in SUDC.

Cerebellar heterotopia of infancy in sudden infant death syndrome: an observational neuropathological study of four cases

Sudden infant death syndrome (SIDS) is the sudden unexpected death of an infant < 1 year of age that remains unexplained after comprehensive workup including complete autopsy and investigation of the circumstances of death. The triple risk hypothesis posits that SIDS results as a combination of both intrinsic and extrinsic factors on the background of a predisposing vulnerability. Neuropathological examination in the past has focussed mainly on the brainstem as the major player in respiratory control, where subtle findings have been linked to the chain of events leading to death in SIDS. The cerebellum has received less attention, probably due to an assumed negligible role in central cardiorespiratory control. We report four cases of SIDS in which neuropathological investigation revealed cerebellar heterotopia of infancy, a distinct malformation of the cerebellum, and discuss the potential impact of this condition on the aetiology and pathogenesis of SIDS.

Geographic Variation in Sudden Unexpected Infant Death in the United States

OBJECTIVES

To assess the geographic variation of sudden unexpected infant death (SUID) and test if variation in geographic factors, such as state, latitude, and longitude, play a role in SUID risk across the US.

STUDY DESIGN

We analyzed the Centers for Disease Control and Prevention's Cohort Linked Birth/Infant Death dataset (2005-2010; 22 882 SUID cases, 25 305 837 live births, rate 0.90/1000). SUID was defined as infant deaths (ages 7-364 days) that included sudden infant death syndrome, ill-defined and unknown cause of mortality, and accidental suffocation and strangulation in bed. SUID geographic variation was analyzed using 2 statistical models, logistic regression and generalized additive model (GAM).

RESULTS

Both models produced similar results. Without adjustment, there was marked geographic variation in SUID rates, but the variation decreased after adjusting for covariates including known risk factors for SUID. After adjustment, nine states demonstrated significantly higher or lower SUID mortality than the national average. Geographic contribution to SUID risk in terms of latitude and longitude were also attenuated after adjustment for covariates.

CONCLUSION

Understanding why some states have lower SUID rates may enhance SUID prevention strategies.

Bedsharing and Breastfeeding: The Academy of Breastfeeding Medicine Protocol #6, Revision 2019

A central goal of the Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient.