For decades, researchers have been trying to understand why some otherwise healthy babies under 1 year old mysteriously die during their sleep. SIDS is the leading cause of infant death in the U.S., affecting 103 out of every 100,000 babies.
The new study found that babies who died of SIDS had abnormalities in certain brain receptors responsible for waking and restoring breathing. The scientists decided to look at the babies’ brains at the molecular level because previous research showed that the same kind of brain receptors in rodents are responsible for protective breathing functions during sleep.
The study was published in the Journal of Neuropathology & Experimental Neurology. The researchers compared brain stems from 70 babies, some of whom died of SIDS and some who died of other causes.
Despite discovering the differences in the babies’ brains, the lead author of the paper said more study is needed.
Robin Haynes, PhD, who studies SIDS at Boston Children’s Hospital, said in a statement that “the relationship between the abnormalities and cause of death remains unknown.”
She said there is no way to identify babies with the brain abnormalities, and “thus, adherence to safe-sleep practices remains critical.”
The American Academy of Pediatrics recommends numerous steps for creating a safe sleeping environment for babies, including placing babies on their backs on a firm surface. Education campaigns targeting parents and caregivers in the 1990s are largely considered successful, but SIDS rates have remained steady since the practices became widely used.
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