To provide a detailed review of the changing epidemiology related to sudden infant death syndrome (SIDS) and sudden unexpected infant deaths (SUID), this chapter begins with an overview of the international system used to code and monitor SIDS trends around the world. Next, we describe the diagnostic shift in reporting and provide possible explanations as to why it occurred. We include a discussion of why using a single code to monitor sudden unexpected and unexplained infant deaths is no longer informative and discuss how new efforts to group codes for surveillance may allow for more consistent monitoring and comparison across jurisdictions and countries. Finally, we provide a description of the epidemiologic profile of SIDS and SUID, including information about current rates and historical trends, and sudden unexpected death in children 1 year old and over.
Current Practice for Coding Cause of Sudden Infant Deaths
Vital statistics data, specifically records from live birth and infant death registration, are the typical source of information on population trends in SIDS and SUID. Causes of death are reported on infant death certificates by a death certifier, who, for unexpected infant deaths without an immediately obvious cause, can be a medical examiner, coroner, or forensic pathologist. To facilitate comparisons across jurisdictions and countries, underlying causes of death reported on death certificates are assigned an International Classification of Diseases or ICD code (1).
The International Classification of Diseases (ICD) coding system was developed by the World Health Organization to catalogue diseases, health conditions, and mortality causes. The coding system is used to monitor death trends and statistics within, and across, jurisdictions and countries (2). The ICD is currently in its 10th Revision (ICD-10). SIDS, first defined in 1969 (3), did not have a unique ICD code assigned until the ICD-9 in 1979. However, in 1973, the US National Center for Health Statistics (NCHS) created a distinct ICD-8 code for SIDS (795.0) for use in the United States (4). SIDS was introduced worldwide in ICD-9 as 798.0. In ICD-10, R95 is the code for SIDS. The SIDS code is indexed in the ICD chapter of nonspecific causes of death.