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3.9: Sudden Unexpected Infant Death (SUID)

  • Page ID
    139642
    • Todd LaMarr
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    SUID

    To support optimal sleep for infants and toddlers, caregivers must be knowledgeable of safe sleep practices. Sudden unexpected infant death (SUID) is a term used to describe the sudden and unexpected death of an infant less than 1 year old in which the cause was not obvious before investigation. These deaths often happen during sleep or in the infant’s sleep area. In the United States about 3,400 infants die suddenly and unexpectedly each year. Sudden unexpected infant deaths include sudden infant death syndrome (SIDS), accidental suffocation in a sleeping environment, and other deaths from unknown causes. Figure \(\PageIndex{1}\) shows the trends in sudden unexpected infant death (SUID) rates in the United States from 1990 through 2019. The SUID rate declined considerably beginning in 1990 following the release of The American Academy of Pediatrics safe sleep recommendations in 1992 and the initiation of the Back to Sleep (now known as Safe to Sleep) campaign that began in 1994. Since 1999, declines have slowed and plateaued. In 2019, the SUID rate was 90.1 deaths per 100,000 live births.

    Trends in Sudden Unexpected Infant Death by Cause, 1990–2019. This chart shows data provided in the figure caption.
    Figure \(\PageIndex{1}\): Trends in Sudden Unexpected Infant Death by Cause, 1990–2019. Causes of deaths per 100,000 live births. The highest trend line was combined SUID rate. Begins at 160 in 1990 and trends downward to 100 in 2018. 2nd highest Sudden infant death syndrome downward trend starting at 160 in 1990 and ending at 100 after 2018. Unknown causes 3rd highest has a gradual upward trend from 22 in 1990 to 30 after 2018, upward trend for accidental death at 5 in 1990 to 20 in 2018. ([1])

    In 2019, there were about 1,250 deaths due to SIDS, about 1,180 deaths due to unknown causes, and about 960 deaths due to accidental suffocation and strangulation in bed.

    Breakdown of Sudden Unexpected Infant Deaths by Cause in 2019. This chart shows data provided in the figure caption.
    Figure \(\PageIndex{2}\): Breakdown of Sudden Unexpected Infant Deaths by Cause in 2019. SUID = 37%, Unknown cause = 34.7%, Accidental suffocation and strangulation in bed = 28.3%. ( [2]

    Figure \(\PageIndex{3}\) is a map showing how sudden unexpected infant death (SUID) rates varied by state from 2015 through 2019 among the 50 U.S. states and the District of Columbia. Vermont, Massachusetts, California, New Hampshire, and New York had the lowest SUID rates.

    Mississippi, Alabama, Arkansas, Louisiana, and South Dakota, had the highest SUID rates.

    The SUID rate in Mississippi (184.7 per 100,000 live births) was almost 4 times the SUID rate in Vermont (46.3 per 100,000 live births).

    SUID Rates by State, 2015–2019 This chart shows data provided in the figure caption.
    Figure \(\PageIndex{3}\): SUID Rates by State, 2015–2019. Alabama 175.8, Alaska 126.8, Arizona 83.3, Arkansas 172.6, California 51.2 Colorado 60, Connecticut 61.4, Delaware 94.1, District of Columbia 122.7, Florida 88.7, Georgia 127.2, Hawaii 79.8, Idaho 74.8, Illinois 90.5, Indiana 106.6, Iowa 96, Kansas 111.1, Kentucky 133.3, Louisiana 157.4, Maine 85.9, Maryland 89.8, Massachusetts 48.9, Michigan 99.8, Minnesota 58.3, Mississippi 184.7, Missouri 101.6, Montana 140.1, Nebraska 88.1,Nevada 116.7, New Hampshire 56.1, New Jersey 61.6, New Mexico 97.3, New York 57.2, North Carolina 113.6, North Dakota 97.2, Ohio 110.3, Oklahoma 151.4, Oregon 88.2, Pennsylvania 92.4, Rhonde Island 88.5, South Carolina 116, South Dakota 154.8, Tennessee 148.7, Texas 90.4, Utah 57.8, Vermont 46.3, Virginia 100.7, Washington 72.4, West Virginia 149, Wisconsin 91.4, Wyoming 108 ([3])

    Although the SUID rate has declined since the 1990s, significant racial and ethnic differences continue. Figure# is a stacked bar chart showing sudden unexpected infant death (SUID) rates by cause and by race/ethnicity in the United States from 2014 through 2018. SUID rates per 100,000 live births for American Indian/Alaska Native (212.1) and non-Hispanic Black infants (186.9) were more than twice those of non-Hispanic White infants (84.9). SUID rates per 100,000 live births were lowest among Hispanic (54.1) and Asian/Pacific Islander infants (34.4). Deaths due to SIDS accounted for the largest proportion of SUID for non-Hispanic Black infants (39%), Asian/Pacific Islander infants (40%), American Indian/Alaska Native infants (42%), and non-Hispanic White infants (43%). Deaths due to unknown causes accounted for the largest proportion of SUID for Hispanic infants (41%). ASSB accounted for the smallest proportion of SUID for all racial groups, ranging from 21% of SUID among Hispanic infants to 26% of SUID among non-Hispanic Black and non-Hispanic White infants.

    Sudden Unexpected Infant Death by Race/Ethnicity. This chart shows data provided in the figure caption.
    Figure \(\PageIndex{4}\): Sudden Unexpected Infant Death by Race/Ethnicity, 2014–2018. Sudden infant death syndrome Sudden infant death syndrome AI/AN=89.5, NHB=72.7, NHW=36.7, Hispanic=20.7 A/PI=13.8, Unknown cause AI/AN=74.3,NHB=65.7, NHW=26.4, Hispanic=22.3,A/PI=13,Accidental suffocation and strangulation in bed AI/AN=48.4,NHB=48.5, NHW=21.8, Hispanic=11.1,A/PI=7.7([4])

    Despite campaigns and the spreading awareness to reduce SIDS by creating safer sleeping environments, caregivers continue to not fully follow the guidelines. For example, Figure \(\PageIndex{5}\) shows the positions caregivers in Sweden place infants to sleep in. While most infants were placed to sleep in a supine position, as recommended, the data revealed that there were still some infants placed to sleep in the prone position (face down) (Wennergren, Strömberg-Celind, Goksör & Alm, 2021). Furthermore, the number of infants placed to sleep in the prone position increased from 2.3% at three months to 3.5% at six months of age.

    Sleeping position of infants when placed to sleep.  This chart shows data provided in the figure caption.
    Figure \(\PageIndex{5}\): Sleeping position of infants when placed to sleep. The position the infants were usually placed in when they were put down to sleep at three and six months of age. Side relates to the combination of side only and alternative use of the side or supine position, while prone relates to the combination of prone only and alternative use of the side or prone, or supine or prone, position. The figure is based on 3,566 (99.3%) responses for three months and 3,579 (99.7%) responses for six months. ([5])

    In the U.S, 22% of mothers reported not placing their baby on their back to sleep, as recommended (see Figure \(\PageIndex{6}\)). The percentage was highest in Black mothers (38%) and young mothers under twenty years of age (30%).

    Percentage of mothers placing infants to sleep on their back. This chart shows data provided in the figure caption.
    Figure \(\PageIndex{6}\): Percentage of mothers placing infants to sleep on their back. Not Placing Baby on Back to Sleep: Overall 22%, White 16%, Black 38%, Hispanic 27%, Asian or Pacific Islander 21%, American Indian or Alaska Native 20%, Age of Mother (years) 19 or less 30, 20-24 28, 25-34 19, 35+ 19 ([6])

    Health care providers and researchers don’t know the exact causes of sudden infant death syndrome (SIDS). However, research shows that caregivers can help reduce the risk of SIDS and other sleep-related infant deaths by doing the following:

    • Place infants on their back for all sleep times—naps and at night.
    • Use a firm, flat sleep surface, such as a mattress in a safety-approved crib, covered by a fitted sheet.
    • Keep soft bedding such as blankets, pillows, bumper pads, and soft toys out of the sleep area.
    • Do not cover an infant’s head or allow them to get too hot. Signs an infant may be getting too hot include sweating or if their chest feels hot.

    1] Image from the CDC is in the public domain.

    [2] Image from the CDC is in the public domain.

    [3] Image from the CDC is in the public domain.

    [4] Image from the CDC is in the public domain.

    [5] Wennergren, G., Strömberg Celind, F., Goksör, E., & Alm, B. (2021). Swedish survey of infant sleep practices showed increased bed‐sharing and positive associations with breastfeeding. Acta Paediatrica, 110(6), 1835-1841. CC by NC 4.0

    [6] Image from “Safe Sleep for Babies” from the CDC is in the public domain.


    This page titled 3.9: Sudden Unexpected Infant Death (SUID) is shared under a mixed 4.0 license and was authored, remixed, and/or curated by Todd LaMarr.