Sudden unexplained death in childhood (SUDC) is the death of a child over the age of 12 months which remains unexplained after a thorough investigation and autopsy. There has not been enough research to identify risk factors, common characteristics, or prevention strategies for SUDC. SUDC is similar in concept to

sudden infant death syndrome Sudden infant death syndrome (SIDS) is the sudden unexplained death of a child of less than one year of age. Diagnosis requires that the death remain unexplained even after a thorough autopsy and detailed death scene investigation. SIDS usuall ...

(SIDS). Like SIDS, SUDC is a diagnosis of exclusion, the concrete symptom of both being

death Death is the irreversible cessation of all biological functions that sustain an organism. For organisms with a brain, death can also be defined as the irreversible cessation of functioning of the whole brain, including brainstem, and brain ...

. However, SIDS is a diagnosis specifically for infants under the age of 12 months while SUDC is a diagnosis for children 12 months and older. The causes of SIDS and SUDC are not definitively known but there are good chances

heart arrhythmia Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adult ...

s and

seizure An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with l ...

s are the main causes. Although it can happen to any child under the age of 18 (after which the deaths are classified as

Sudden arrhythmic death syndrome Sudden arrhythmic death syndrome (SADS) is a sudden unexpected death of adolescents and adults, mainly during sleep. One relatively common type is known as Brugada syndrome. The syndrome is rare in most areas around the world but occurs in po ...

(SADS), it is most common in those aged between 1-4 years.

Hypotheses

Researchers are exploring a possible connection between sudden unexplained death in toddlers,

febrile seizure A febrile seizure, also known as a fever fit or febrile convulsion, is a seizure associated with an increased body temperature Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even whe ...

s, and

hippocampal The hippocampus (via Latin from Greek , 'seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, an ...

anomalies. The occurrence of fever before the sudden deaths later in sleep, could explain the febrile seizure hypotheses

Epidemiology

SUDC is rare, with a reported incidence in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

of 1.2 deaths per 100,000 children, compared to 54 deaths per 100,000 live births for SIDs. There are approximately 400 deaths per year of SUDC in the U.S,with over 200 of these cases being the children aged 1-4 years. SUDC deaths have occurred at the following sites: * Death at home, history provided: 79% * Crib or bassinet: 54% * Adult bed: 36% The placed and found positions were as follows: * Placed

supine In grammar, a supine is a form of verbal noun used in some languages. The term is most often used for Latin, where it is one of the four principal parts of a verb. The word refers to a position of lying on one's back (as opposed to ' prone', l ...

, side, prone*: 10%, 2%, 3% * Found

prone Prone position () is a body position in which the person lies flat with the chest down and the back up. In anatomical terms of location, the dorsal side is up, and the ventral side is down. The supine position is the 180° contrast. Etymolog ...

: 89% * Found face position: down, side: 10%, 8% *

Co-sleeping Co-sleeping is a practice in which babies and young children sleep close to one or both parents, as opposed to in a separate room. Co-sleeping individuals sleep in sensory proximity to one another, where the individual senses the presence of othe ...

, sweating when found: 3%, 1% _{*applies only to youngest children}

History

At the SIDS Alliance national convention in

Atlanta, GA Atlanta ( ) is the capital and most populous city of the U.S. state of Georgia. It is the seat of Fulton County, the most populous county in Georgia, but its territory falls in both Fulton and DeKalb counties. With a population of 498,715 ...

in 1999 Dr. Henry Krous gave a presentation titled "Post-Infancy SIDS: Is it on the rise?" This led to the beginning of the San Diego SUDC Research Project. The first definition of SUDC was published in 2005 in ''

Pediatric and Developmental Pathology ''Pediatric and Developmental Pathology'' is a bimonthly peer-reviewed medical journal covering clinical pathology as it relates to pediatrics. It was established in 1998 and is published by SAGE Publications. It is the official journal of the ...

''.

References

Causes of death Ailments of unknown cause Pediatrics Death of children