Study brings hope of identifying SIDS cause
OTTAWA — When he goes paddle boarding near his home, Rohit Saxena often leaves his glasses by a willow tree, telling his children that “Jaya will watch them for me.”
The tree bears a plaque with Jaya Anita Spencer Saxena’s name on it. The daughter of Saxena, an engineer, and his wife Lesley Spencer, an emergency room physician, was just six months old when she died of sudden infant death syndrome (SIDS) in 2016 while the family was on vacation. The willow is one of two trees they have planted in her memory.
Saxena, who has written about and spoken to other grieving fathers about his family’s experience with SIDS, says one thing that has helped him is to avoid spending too much time looking “in the rear-view mirror.” But in recent days, he has been drawn there.
The release of a study that identified a biomarker its authors say is potentially related to sudden infant death syndrome has sent ripples around the world and left parents like Saxena and Spencer wondering whether science might someday be able to prevent tragedies like theirs.
For some families, the research offers the possibility that there could be a clear biological explanation for the devastating sudden death of their child. The study’s lead author, who herself lost a child to SIDS, has talked about wanting to find a scientific explanation for her toddler’s sudden death.
But observers, including the director of Newborn Screening Ontario, based at CHEO, urge caution around the findings, which focus on an enzyme that plays a role in arousal from sleep.
Dr. Pranesh Chakraborty, director of Newborn Screening Ontario, said he would love to be able to identify infants who might be more vulnerable to SIDS, the way the program he heads helps identify other genetic risk factors in newborns.
“Anything where we could identify babies at risk and change their outcome …”
But Chakraborty said the Australian study is not the breakthrough many are looking for.
“I don’t see this being a step to something imminent,”
“Anything where we could identify babies at risk and change their outcome …”
Dr. Pranesh Chakraborty Newborn Screening Ontario
he said.
Like others, Chakraborty says the study, published earlier this month in the journal eBioMedicine, is interesting but much more work is needed to better understand whether there is a biomarker that puts some children at increased risk.
The study found low levels of the enzyme butrylcholines-terase (BChE) in blood samples taken shortly after birth of children who later died from SIDS. The enzyme BChE plays a role in the brain’s arousal pathway and researchers believe it could affect an infant’s ability to wake, making them more vulnerable to SIDS.
But Chakraborty said the findings do not show a causal relationship between the enzyme and SIDS. And he said the study shows overlap between levels of the enzyme in babies who died from SIDS and those who died from another cause, meaning there is not a clear difference.
“I would say it generates a lot of ideas and hypotheses, but it doesn’t answer questions about a mechanism or biomarker without a lot more work,” he said.
Mary Margaret Murphy, executive director of the charity Baby’s Breath, which supports Canadian families affected by SIDS, said she is thrilled that more attention is being paid to the issue.
“This is a great start, but we need more research to understand its significance,” she said of the Australian study.
Murphy said there is research happening around the world, including work focusing on the issue of arousal from sleep as a possible factor in SIDS.
But safe sleep policies and education are also a key factor in reducing SIDS deaths, she said.
Between 1999 and 2004, the rate of SIDS in Canada decreased by 50 per cent. That coincided with the launch of recommendations to place infants on their backs to sleep, according to the Public Health
Agency of Canada. The decline could also be related to a decrease in maternal smoking during pregnancy and an increase in breastfeeding.
“The most important modifiable risk factors for SIDS are infants sleeping in the prone position, and exposure to tobacco smoke prenatally and after birth,” according to a 2021 statement on safe sleeping from the federal government, the Canadian Paediatric Society and Baby’s Breath Canada.
Murphy said safe sleep guidelines must continue to be promoted, even if there is eventually a way to screen for infants who are at increased risk of SIDS.
Chakraborty said he believes the cause of SIDS will always be multilayered — a combination of risk, environmental and developmental factors. But having a means to identify children at risk and intervening early would be a major step.
Saxena remains cautious, but optimistic about the research.
“It is an early step on a longer trip. Even though I want to be rational, I want to see hope where it exists and that, after more work, maybe some families might be spared what we went through.”