Unsafe sleep practices and an analysis of bedsharing among infants dying suddenly and unexpectedly: Results of a four-year, population-based, death-scene investigation study of sudden infant death syndrome and related deaths

Background. Prone sleep and unsafe sleep surfaces increase the risk of sudd en infant death. Recent epidemiologic studies also suggest that when an inf ant's head or face is covered by bedding, or when a sleep surface is shared with others, the risk of dying increases. The inference of a causal role f or these risk factors is supported by physiologic studies and by the consis tent finding that fewer infants die when risk factors are reduced. The prev alence of most of these risk factors in infant deaths in the United States is uncertain. Objective. To describe the prevalence of several important risk factors rel ated to sleep practices among a defined population of infants dying suddenl y and unexpectedly. Methods. In this population-based study, we retrospectively reviewed death- scene information and medical examiners' investigations of deaths in the ci ty of St Louis and St Louis County between January 1, 1994 and December 31, 1997. Because of the potential for diagnostic overlap, all deaths involvin g infants <2 years old with the diagnoses of sudden infant death syndrome ( SIDS), accidental suffocation, or cause undetermined were included. Results. The deaths of 119 infants were studied. Their mean age was 109.3 d ays (range: 6-350). The diagnoses were SIDS in 88 deaths, accidental suffoc ation in 16, and undetermined in 15. Infants were found prone in 61.1% of c ases and were found on a sleep surface not designed for infants in 75.9%. T he head or face was covered by bedding in 29.4%. A shared sleep surface was the site of death in 47.1%. Only 8.4% of deaths involved infants found non prone and alone, with head and face uncovered. Conclusions. Using detailed death-scene descriptions, we found that similar unsafe sleeping practices occurred in the large majority of cases diagnose d as SIDS, accidental suffocation, and cause undetermined. Considering thes e diagnoses together may be useful in public health campaigns during a time when there may be diagnostic overlap. Regardless of the diagnosis, recomme ndations that infants sleep supine on firm sleep surfaces that lessen the r isk of entrapment or head covering have the potential to save many lives. C ampaigns are needed to heighten awareness of these messages and of the risk s of dangerous bedsharing.