New Research on Sudden Infant Death Syndrome (SIDS)

New Research on Sudden Infant Death Syndrome (SIDS)

Sudden unexpected infant deaths (SUIDs) are the leading cause of infant death in the United States and most western countries for infants. The most recognizable SUID is Sudden Infant Death Syndrome (SIDS). When no cause of death can be found after a thorough death scene investigation, complete autopsy and a review of the infant’s medical record, the cause of death becomes SIDS if the infant is between 1 month and 1 year of age.   

SIDS has no known cause at this time but is believed to have multiple factors that lead to the death of the infant. The leading theory for the cause of SIDS is the Triple Risk Model, which is defined as three specific factors coming together to cause the death. The three factors are a vulnerable infant, in a critical period of development (2-4 months), and environmental stressors like exposure to cigarette smoking during and after pregnancy, soft mattresses, bedding and objects in the bed, co-sleeping, etc. When these three factors overlap, the incidence of SIDS increases.  

Since 1994 the American Academy of Pediatrics has made recommendations to help decrease the incidence of SIDS and SUIDs by eliminating the environmental factors that has been proven to cause SUIDs. As a result, the number of infants dying of SIDS has decreased but has not been eliminated. Researchers continue to try to find the underlying reasons that increase the risk of SIDS. While no clear answer has been found yet, the thought is that those infants have a decreased ability to arouse themselves.       

Recently a new research study was released online, with findings that could be the key to determining what an underlying vulnerability is in babies that die from SIDS, despite being in a safe sleep environment. The authors describe decreased levels of the blood enzyme butryrylcholinesterase (BChE) activity in infants that died from SIDS versus those that died from other causes, versus those who did not die.  

In the case-controlled study the authors compared dried blood samples that had been obtained from babies at 2-3 days of age from infants that had died from SIDS, infants that died in the first year but not due to SIDS, and controls of infants who did not die matching for age and sex. The results demonstrated that those infants who died from SIDS had statistically significant decreased BChE activity level when compared to the controls and the babies who died but not from SIDS.  The authors also looked at the BChE level of those babies that died but not from SIDS and compared to their controls and did not find a statistically significant difference in the BChE activity level. As the sample size was small, there are limitations to the study.

While these findings seem to have found a possible medical reason for the unexplained deaths, more research needs to be done before it can be confirmed. In the meantime, healthcare providers need to continue to teach the ABC’s of safe sleep and families need to continue utilizing the ABC’s of sleep for all infants from birth to 1 year of age in order for all infants to have a chance to grow up to lead healthy productive lives!