Recurrent sudden unexpected death in infancy: a case series of sibling deaths

Abstract

ObjectivesTo determine the rate of sudden unexpected death in infancy (SUDI) for infants born after a previous SUDI in the same family, and to establish the causes of death and the frequency of child protection concerns in families with recurrent SUDI.DesignObservational study using clinical case records.SettingThe UK’s Care of Next Infant (CONI) programme, which provides additional care to families who have experienced SUDI with their subsequent children.PatientsInfants registered on CONI between January 2000 and December 2015.Main outcome measuresCause of death, presence of modifiable risk factors for SUDI and child protection concerns.ResultsThere were 6608 live-born infants registered in CONI with 29 deaths. 26 families had 2 deaths, and 3 families had 3 deaths. The SUDI rate for infants born after one SUDI is 3.93 (95% CI 2.7 to 5.8) per 1000 live births. Cause of death was unexplained for 19 first and 15 CONI deaths. Accidental asphyxia accounted for 2 first and 6 CONI deaths; medical causes for 3 first and 4 CONI deaths; and homicide for 2 first and 4 CONI deaths. 10 families had child protection concerns.ConclusionsThe SUDI rate for siblings is 10 times higher than the current UK SUDI rate. Homicide presenting as recurrent SUDI is very rare. Many parents continued to smoke and exposed infants to hazardous co-sleeping situations, with these directly leading to or contributing to the death of six siblings. SUDI parents need support to improve parenting skills and reduce risk to subsequent infants.

Risk Factors for Sudden Infant Death in North Carolina

“…Our results also agree with other studies that have shown that Non-Hispanic Black infants are at a disproportionately high SIDS risk (12,18). We also find that lower maternal education level (19), lower maternal age, male sex of the baby, and prior sibling death are associated with increased SIDS risk (20). Many of these associations have been previously shown in other studies; however, this study utilizes a more robust statistical approach, with a multivariable model, in a larger and more recent population to demonstrate FIGURE 2 | Forest plot of adjusted odds ratios for exposure to various covariates in SIDS vs. non-SIDS infants with confidence intervals.…”

“…Finally, while not statistically significant, we observed an association between SIDS and at least one of the mother's previous births now deceased. This association can be explained both by the growing literature on evidence of the role of genetic predisposition in SIDS, as well as the fact that siblings may experience similar parental child-care practices (20,33,34). To gain more insight into the heritability of SIDS on a population level, sibling and twin studies must be performed.…”

Risk of Sudden Infant Death Syndrome Among Siblings of Children Who Died of Sudden Infant Death Syndrome in Denmark

“…A positive familial aggregation study is an important step to suggest the usefulness of clinical genetic work-up of the families. Even though positive family history of SIDS has been described, 8 , 9 , 10 , 11 , 12 , 13 , 14 it is unknown whether a familial aggregation exists in the general population. Previous studies of familial aggregation were performed on small and/or selected populations 8 , 9 , 10 , 11 , 12 ; therefore, a nationwide study on an unselected pediatric population with information on family history is warranted to establish a familial clustering of children who died of SIDS.…”

Sudden Unexplained Death in Childhood

“…Genetic investigations in SUDC involve small cohorts with heterogeneous findings, yet common substrates are suggested. A hereditary contribution to SUDC is supported by the observation of recurrent cases within families and the increased risk of SIDS/SUDC in the presence of a family history of such a death 31 . In practice, clinical genetic testing most frequently relies on panels of genes associated with a common phenotype that may cause sudden death, such as epilepsy, cardiomyopathies, or cardiac arrhythmias, due to cost limitations.…”

“…A hereditary contribution to SUDC is supported by the observation of recurrent cases within families and the increased risk of SIDS/SUDC in the presence of a family history of such a death. 31 In practice, clinical genetic testing most frequently relies on panels of genes associated with a common phenotype that may cause sudden death, such as epilepsy, cardiomyopathies, or cardiac arrhythmias, due to cost limitations. Alternatively, research groups often take a hypothesis-free approach using exome sequencing or genome sequencing, in which genome-wide sequencing is performed and analyzed for potential causal variants.…”