The Disappearance of Sudden Infant Death Syndrome: Has the Clock Turned Back?

Sudden Infant Death Syndrome (SIDS) is defined as a sudden unexpected death of an infant younger than 1 year who was previously well and in whom postmortem examination fails to identify the cause of death. The diagnostic term SIDS was first proposed at the Second International Conference on Causes of Sudden Infant Death in 1969, at a time when close to 9000 cases of sudden unexpected infant death (SUID) occurred in the United States alone.1 The term SIDS served 3 main purposes: to encourage and focus research into these tragic deaths, to comfort parents with knowledge that the death was the result of a natural disease entity, and to absolve parents or caregivers of any blame for the death of their infant. Although considerable progress has been made since then, particularly in understanding the potential risk factors and biological underpinning, during the last decade the use of SIDS as a diagnosis has fallen out of favor. In many jurisdictions, the use of this term has been reduced considerably or abandoned altogether. For example, reports from the Office of the Chief Medical Examiner from Wayne County, Michigan, and New York, New York, indicate a 95% and 84% decline in SIDS diagnoses, respectively. In the province of Ontario (population 13.5 million, with about 128 cases of SUID recorded yearly), not a single case of SIDS has been diagnosed during the past 2 years.2,3 It appears that the clock has been turned backward and that the diagnostic term SIDS is disappearing. Instead, coroners and medical examiners are reverting to terminology employed in the past such as pneumonia, suffocation, and, most commonly, “undetermined.” This diagnostic shift cannot help but have a profound effect on the affected families as well as dampen the enthusiasm for basic scientific research. There are 3 main reasons for the change: (1) the prevailing philosophy of forensic pathologists trained in the investigations of violent deaths without a background in pediatric pathology, (2) the emphasis by public health agencies and the American Academy of Pediatrics on prevention of SUID through modifying infants’ sleep environment, and (3) the disappearance of advocacy groups responsible for securing research funds and reforming death investigation practices.