Prone sleeping position and incidence of SIDS - sudden infant death syndrome - Tips from Other Journ

Date: Feb 1, 1994

Results from at least 13 retrospective studies and one prospective study indicate that the prone sleeping position increases the risk of sudden infant death syndrome (SIDS). However, the exact mechanism to explain this observation is not known. Ponsonby and colleagues analyzed data from a case-control study and a prospective study performed in Australia to identify factors that increased the associated risk between the prone sleeping position and SIDS.

The case-control study involved 58 infants with SIDS and 120 control subjects matched for age, birth weight, region and external temperature in that region. The prospective study involved 22 infants with SIDS and 213 control subjects. A comprehensive set of potential variables were analyzed, including parental sociodemographic factors, the sleeping environment and the infant's health status.

In the case-control study, SIDS was 4.5 times more likely to occur among infants sleeping in the prone position than in infants sleeping in other positions. In infants who slept prone, the risk of SIDS was further increased by four factors: sleeping on a natural-fiber mattress, use of swaddling, sleeping in a heated room and recent illness. In the cohort study, the risk of SIDS was also greater among infants who slept prone on natural-fiber mattresses. The "natural-fiber mattresses" in these studies were described as "soft and fluffy" and would easily indent with minimal pressure. In these studies, the prone sleeping position increased the risk of SIDS almost 20-fold if the infants slept on these natural-fiber mattresses, but only threefold if the infants slept on foam or other mattresses.

The results of these studies suggest that several factors, especially the use of natural-fiber mattresses, may increase the risk of SIDS among Australian infants who sleep in the prone position.

In an accompanying editorial, Poets and Southall note that the common use of soft mattresses and sheepskins in Australia may explain the relatively high SIDS rates, despite the low incidence of infants sleeping in the prone position. They note that the routine use of firmer mattresses in the United States may partly explain the relatively lower rate of SIDS, despite the higher incidence of infants sleeping in the prone position. Although the exact mechanisms remain unclear, they conclude that the most important message for physicians is to advise parents to place healthy infants on their side or back when preparing them for sleep. (New England Journal of Medicine, August 5,1993, vol. 329, pp. 377,425.)

COPYRIGHT 1994 American Academy of Family PhysiciansCOPYRIGHT 2004 Gale Group

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