Objective: To study factors associated with sudden infant deaths occurring with the external airways (ie, nose and mouth) covered by bedding.
Design: Case-comparison study of infants dying with vs those dying without the external airways covered.
Setting: Death-scene investigation and reconstruction at the site of death using an infant mannequin; 18 metropolitan areas.
Participants: Caregivers for a consecutive sample of infants who died of sudden infant death syndrome (SIDS). Complete data from 206 of 382 eligible cases.
Main outcome measures: Among infants dying suddenly and unexpectedly, an analysis of whether sociodemographic risk factors for SIDS, sleep practices, or bedding increased the risk of dying with the external airways covered.
Results: Data were analyzed by using univariate and 2 types of multivariate risk analysis, logistic regression and latent class. Of the victims, 59 (29%) were found with the external airways covered. Conventional risk factors for SIDS did not affect the risk of death with the external airways covered. Factors increasing the risk of death with the external airways covered included prone sleep position (odds ratio [OR], 2.86) and using soft bedding (OR, 5.28), such as comforters (OR, 2.46) and pillows (OR, 3.31). Infants at low risk for death with the external airways covered slept in the prone position, but rarely on a pillow, comforter, or other bedding that allowed a pocket to form beneath the face. All 9 infants who were positioned supine or on one side for sleep and found with the external airways covered had turned and were found dead in the prone position.
Conclusions: Sudden infant deaths with the external airways covered were common in the United States when most infants slept prone. Soft bedding, including pillows and comforters, increased the risk that an infant who died would be found with the external airways covered. Therefore, these items should not be placed near infants, regardless of the sleep position.