Babies who died from sudden infant death syndrome, or SIDS, show lower amounts of the brain chemical serotonin, says a study published Wednesday in the Journal of the American Medical Association.
Levels of serotonin, which regulate a baby’s sleep, heart rate and breathing, were 26 percent lower in the brainstems of babies who died of SIDS than in those of babies who died of other causes, the study says.
Researchers believe a low level of serotonin may be the “fundamental abnormality” in babies who die from SIDS. In the brainstem, serotonin acts as an alarm system, waking up a baby when breathing is disrupted. Babies without it can be unaware that they are not breathing enough oxygen, causing them to die in their sleep, according to the study.
The study also found that infants with insufficient serotonin also had low levels of the enzyme tryptophan hydroxylase, which is needed to make serotonin. Levels of that were 22 percent lower in SIDS babies.
The next phase of the study, which was funded by the National Institutes of Health in Bethesda, Maryland, will focus on why some babies lack enough tryptophan hydroxylase to produce serotonin, said the study’s author, Dr. Hannah Kinney, who is affiliated with Children’s Hospital Boston in Massachusetts.
There is no test to determine which infants may be at risk for SIDS. Kinney told CNN that researchers believe they are decades away from discovering a physical marker of a brainstem problem that could be identified in the blood.
To avoid the risk of SIDS, she and other doctors recommend that parents make sure that babies can breathe uninhibited during sleep: Place babies on their backs to avoid their rolling over, don’t over-bundle the baby, and don’t leave loose bedding or stuffed toys in the crib.
Dr. Court’s Comments
This information is truly intriguing. We routinely check the levels of serotonin of adults in our clinic. We have not, until this point, checked the levels of babies. I could be done because it is a simple urine and saliva test. I also wonder what the implications of the mother’s diet will be when this is studied further. I don’t think it is a large leap to assume that mother’s deficient in serotonin might also have babies that are deficient in serotonin. Serotonin is made in the body from the amino acid tryptophan. This is then converted into 5-hydroxytryptophan, or 5-HTP, which is directly converted into serotonin. This 5-HTP is a supplement that is very easily taken. There is no research thus far into how low levels of available 5-HTP in the mother may correlate into SIDS in a child, but I will be interested to see how it plays out. It stands to reason that low levels in the mother may translate into low levels in the baby. This, in turn, may increase the likelihood of SIDS.