Sudden infant mortality syndrome is a mystery. It’s the sudden and unavoidable death of a child younger than one. Researchers are getting closer to understanding the mechanisms and risk factors that lead to SIDS.
Three possible causes are suggested by the prevailing theory: first, the infant’s development is critical during the first year. The baby may be exposed to stressors, like sleeping on their backs, which could lower oxygen levels in the blood and increase carbon dioxide. Third, the baby has an abnormality that makes it more difficult to survive this traumatic experience.
The Journal of Neuropathology & Experimental Neurology published a study on Thursday that points out one such abnormality.
Researchers at Boston Children’s Hospital, Rady Children’s Hospital San Diego and the University of California San Diego discovered that some SIDS infants had a brain receptor altered. This receptor is likely to be involved in helping babies gasp . The receptor is a part of the serotonin systems, which regulates involuntary functions such as heart rate, blood pressure, and breathing.
The majority of SIDS deaths occur during sleep. It is the most common cause of infant death in the U.S. In 2020, the Centers for Disease Control and Prevention estimated that nearly 1,400 infants died from SIDS.
Researchers from the new study compared brain tissue samples of 58 infants that died of SIDS in the period 2004-2011 with brain tissue samples of 12 infants that died of pneumonia or heart disease. The researchers found that babies who died from SIDS had a more altered version of a brain receptor related to serotonin than control cases.
Robin Haynes is the lead author of the study and a researcher from Boston Children’s Hospital. She said that babies have a natural protective response which causes them to gasp when they do not get enough oxygen while sleeping.
She said, “They wake up and go through auto-resuscitation where breathing is triggered.”
SIDS may cause this response to not occur, possibly due to a brain receptor that is altered. When an infant cannot restore his or her breathing and heartbeat, it can affect blood flow and oxygen.
There are many theories on SIDS
The Boston-based group of researchers behind the new study have been studying the relationship between SIDS, serotonin and brain tissue for over three decades. They’ve published numerous papers based on different analyses of the same samples.
These samples are the only ones that researchers of SIDS have. This small sample size, however, makes it difficult to draw any strong conclusions about possible causes or risk factors. Dr. Jose Javier Otero is the director of neuropathology in The Ohio State University College of Medicine.
Otero stated that it was “almost courageous” to try and make a conclusion.
Researchers have suspected for a long time that serotonin may play a role in SIDS due to its association with breathing.
Dr. Debra Mayer, head of the pediatric autonomic division at Lurie Children’s Hospital in Chicago said: “It is logical that serotonin would be a major player.” The question is, “Is it the only one?”
Weese Mayer stated that scientists don’t know how genetics affects a baby’s susceptibility to SIDS.
According to Dr. Michelle Caraballo a pediatric pulmonologist with Children’s Health of North Texas, and assistant professor at UT Southwestern, another factor could be early-life infections.
The winter is the season when SIDS rates are at their highest. She said that the winter is also the time when viral infections are most prevalent in infants.
How to lower your baby’s risk as a parent
There are no tests that can determine if a baby is predisposed to SIDS. Since no causes of SIDS have been proven, there are also no treatments available to reduce the risk. Haynes says researchers aren’t giving up hope.
She said that one day, if you can identify an infant who has a certain abnormality, a preventative treatment will be available. However, we don’t know what it looks like.
However, there are ways to protect yourself against SIDS.
The CDC recommends parents always place their sleeping babies on the back. The baby’s sleeping area should be flat, firm and free from soft toys, bedding, and blankets. Parents should not cover their baby’s face during sleep. Babies should sleep in the same bedroom as their parents for at least six months.
The American Academy of Pediatrics also suggests giving a baby a pacifier during naptime and at bedtime, once they are comfortable with breastfeeding.
It has been proven that breastfeeding lowers the risk of SIDS. However, drinking alcohol or smoking while pregnant can increase the risk.
Caraballo stated that “we do want people to adhere to the safe sleeping guidelines as much as they can.” The scary part is that you can do everything right, and still the baby die. In the majority of deaths, we do not know the exact cause.
