Sudden infant death syndrome usually occurs while the baby is asleep. Experts speculated that it was linked to problems in the part of the infant’s brain that controls breathing and waking. BChE is an enzyme of the cholinergic system, part of the autonomic system, that controls functions such as blood pressure and breathing. The study authors say more research is needed to determine whether BChE tests are able to identify and prevent future cases of SIDS.
Smoking during pregnancy is a risk factor for SIDS, along with things like family history and preterm birth. The researchers note that animal studies have shown an association between passive smoking and a lower level of BChE. However, many other changes in the first six months of life are also likely to affect these enzymes and the nervous system in general.
“Children have a very powerful mechanism for letting us know when they are not happy. Typically, if a child experiences a life-threatening situation, such as difficulty breathing while sleeping because they are on their stomachs, they will wake up and scream. What this research has shown is that some children do not have the same strong arousal response,” he said. Harrington Network.
This study shows that BChE is involved in the lack of arousal, Harrington said.
“Now that we know that BChE is involved, we can begin to change the outcome for these children and make SIDS a thing of the past,” she said.
Study limitations include that the blood samples were more than two years old, so the results do not reflect BChE activity in fresh blood. The researchers also used forensic diagnoses rather than autopsy results and included data on children aged one to two years, even though SIDS is defined as involving a child less than a year old.
Dr. Rachel Munn, chair of the American Academy of Pediatrics’ task force on SIDS, noted the study’s small sample size and said the results were not definitive.
“While the differences in blood levels of this enzyme were statistically different – even if confirmed by additional, larger studies – there is enough overlap in blood levels between cases and controls that it cannot be used as a blood test at this point with any reasonable predictive value.”
First Candle, a national organization focused on eliminating sleep-related infant deaths and supporting families, welcomed the research but also urged caution.
“This is progress, which is why we should be optimistic, but this is not the complete solution,” Chief Executive Officer Alison Jacobson said in a statement. “Our concern with developing a vulnerability test for SIDS is with parents having a false sense of security and adopting unsafe sleep practices.”