Skip to content

    Health & Baby

    Font Size
    A
    A
    A

    Clue to Sudden Infant Death Syndrome

    Brain Stem Abnormality Seen in SIDS Babies, Study Shows
    By
    WebMD Health News
    Reviewed by Louise Chang, MD


    Oct. 31, 2006 - Researchers have identified a brain defect they think is a major contributor to sudden infant death syndrome (SIDS).

    The findings provide the strongest evidence yet of a specific neurological cause for SIDS, a little-understood condition that kills roughly 2,500 infants each year in the United States.

    In the study, autopsy tissue taken from babies who had died of SIDS and other causes showed abnormalities in the lower brain stems of the SIDS babies. Among other things, this region of the brain is thought to help regulate breathing and arousal.

    Environmental factors, such as stomach sleeping, overheating, and exposure to cigarette smoke are all believed to increase a baby's risk of death from SIDS.

    But the search for a biological link has turned up little, until now.

    "This is very good evidence that there definitely is a biological problem that contributes to SIDS," neuroscientist and study co-author David S. Paterson, PhD, tells WebMD.

    "There very well may be other biological causes which have not been identified. This gives us a good starting point to keep looking," says Paterson, of Boston Children's Hospital.

    The Serotonin System

    Boston Children's Hospital neuropathologist Hannah Kinney, MD, has searched for a biological cause for SIDS for the past two decades.

    She and Paterson had previously identified defects in the serotonin system of the lower brain stem in babies who had died of SIDS.

    The brain stem serotonin system is believed to help coordinate breathing, blood pressure, sensitivity to carbon dioxide, arousal, and temperature. Serotonin works as a chemical messenger in this system.

    Kinney and Paterson believe babies who die of SIDS actually suffocate from breathing the carbon dioxide they exhale during sleep.

    Normal babies wake up when the air they breathe contains too much carbon dioxide and not enough oxygen, but the thinking is that babies susceptible to SIDS lack this arousal reflex.

    In their latest study, which appears in the Nov. 1 issue of The Journal of the American Medical Association, the researchers confirmed their earlier findings and expanded on them.

    Brain Abnormality

    They examined autopsied tissue from the lower brain stems of 31 infants who had died of SIDS and 10 infants who had died from other causes.

    Baby's First Year Newsletter

    Because every week matters, get expert advice and facts on what to expect in your baby's first year.

    Today on WebMD

    mother on phone holding baby
    When you should call 911.
    parents and baby
    Unexpected ways your life will change.
     
    baby acne
    What’s normal – and what’s not.
    baby asleep on moms shoulder
    Help your baby get the sleep he needs.
     

    mother holding baby at night
    ARTICLE
    mother with sick child
    QUIZ
     
    Chinese mother breast feeding newborn baby girl
    SLIDESHOW
    Track Your Babys Vaccines
    TOOL
     
    Baby Napping 10 Dos And Donts
    Slideshow
    Mother with her baby boy
    Article
     
    baby in crib
    Slideshow
    baby gear slideshow
    Slideshow