Scientists claim to have found a cause of Sudden Infant Death Syndrome (SIDS), a “world first breakthrough” that has the potential to one day reduce the number of babies who die unexpectedly.
Researchers at Children’s Hospital Westmead in Australia found that levels of an enzyme called butyrylcholinesterase (BChE) were significantly lower in babies who later died of SIDS.
Since BChE is known to play a role in the brain’s arousal pathway, the researchers argue that a deficiency of the enzyme likely reduces an infant’s ability to wake up or respond to the external environment, increasing the risk of SIDS.
The research was recently published in the journal The Lancet. eBioMedicine. It was led by Dr. Carmel Harrington, an honorary investigator at Children’s Hospital at Westmead, who lost her own son to SIDS 29 years ago and has since dedicated her career to discovering the cause of this tragic syndrome.
“A seemingly healthy baby who falls asleep and doesn’t wake up is every parent’s nightmare and until now there was no way of knowing which baby would succumb. But that is no longer the case,” Dr. Harrington said in a statement.
“Babies have a very powerful mechanism to let us know when they are not happy. Usually, if a baby is faced with a life-threatening situation for her, such as difficulty breathing in her sleep because she is on her tummy, she will wake up and cry. What this research shows is that some babies do not have this same robust arousal response,” she explained.
SIDS, sometimes known as “sudden death,” is the sudden and unexpected death of an apparently healthy baby less than a year old. The Centers for Disease Control and Prevention estimates that there are about 3,400 cases of SIDS and other unexpected childhood deaths in the US each year. Fortunately, rates of the syndrome have been declining since the 1990s, although significant racial and ethnic differences still exist, particularly among Native Americans, Alaskan Natives, and blacks.
To arrive at their findings, the team analyzed BChE levels in 722 dried blood spots (DBS) taken at birth as part of the Newborn Screening Program. BChE levels were measured in both SIDS-related deaths and babies who died of other causes, then compared with 10 surviving babies with the same date of birth and gender.
Armed with this knowledge, the team says that babies could potentially be screened for BChE so that parents and doctors understand if they are at increased risk of SIDS. The researchers also hope to continue research looking for ways to address enzyme deficiency and actively reduce the risk of SIDS in high-risk infants.
“This discovery has opened up the possibility of intervention and finally gives answers to parents who have lost their children so tragically. These families can now live with the knowledge that this was not their fault,” said Dr. Harrington.
While the findings are promising, some groups have urged some caution when reading bold headlines about the research.
“The findings of this study are interesting and more work needs to be done,” the Lullaby Trust, a British charity that aims to prevent unexpected childhood deaths, said in a statement sent to IFLScience.
“While the research is ongoing, we urge all parents and caregivers of infants to follow evidence-based safer sleep advice to reduce the risk of SIDS occurring. This includes: always put infants to sleep on their backs.” upstairs in a clear sleeping space on a flat, firm, waterproof mattress with no bulky bedding, pillows, or bumper pads,” they added.
“Claims that a cause of SIDS has been found could give false hope to families whose baby has died suddenly and unexpectedly and may downplay the continued importance of safer sleeping advice.”
Updated on 05/13/2022: This article has been updated to include a statement from the Lullaby Trust.
