Experts Weigh In On New Biomarker Findings For SIDS Risk

Scientists in Australia have identified a potential biomarker for sudden infant death syndrome (SIDS), according to a new study published in the journal eBioMedicine. Researchers from the Children's Hospital at Westmead in Australia measured levels of an enzyme called butyrylcholinesterase (BChE) in the blood of 67 infants who died unexpectedly between 2016 and 2020 and compared them with the blood of 655 living children (via CNN).

The study found that the BChE levels in children who had died of SIDS were much lower than the living children or those whose deaths were not SIDS-related. BChE is an enzyme in the cholinergic system, which is part of the autonomic nervous system — the control system that regulates involuntary bodily functions, like heart rate and breathing. While scientists have long speculated that the part of the brain that controls waking and breathing could play a role in SIDS, further research is still needed to determine whether or not BChE tests could help identify and prevent future SIDS cases and deaths.

Since the study's publication, however, pediatric experts have been pushing back against news and media reports suggesting that researchers have identified the cause of SIDS (via Healthline). Although the study is a step in the right direction, experts agree that it is too small and too limited to definitively determine the cause of SIDS or assess the risk of SIDS in infants in the future.

"BChE levels will never be a true standalone clinical biomarker that can predict SIDS for an individual baby," Dr. Kristina Uban, an assistant professor of public health at the University of California Irvine, told Healthline. However, this doesn't mean that the study's findings aren't important. According to Uban, they are proof that low cholinergic activity contributes to SIDS.

For parents concerned about the risk of SIDS, pediatrician Dr. Danelle Fisher recommends laying infants on their backs when they sleep and placing them on a firm surface with soft bedding. Fisher also says that parents should only dress their children in one layer of clothing and use pacifiers that aren't attached to any strings or toys. "Finally, avoidance of cigarette smoke is important to help prevent SIDS," she said.