Where should infants sleep? A comparison of risk for suffocation of infants sleeping in cribs, adult beds, and other sleeping locations.

OBJECTIVES

To ascertain whether the number of sudden infant deaths as a result of suffocation in cribs, in adult beds, on sofas or chairs, and on other sleep surfaces was increasing whether attributable to increased reporting, diagnostic shift, or an actual increase in suffocation deaths and to compare the risk of reported accidental suffocation for infants on sleep surfaces designed for infants with the risk on adult beds.

METHODS

We reviewed all accidental suffocation deaths among infants < or =11 months of age reported to the United States Consumer Product Safety Commission from 1980 through 1983 and 1995 through 1998. We compared infants' ages and other demographic data, the sleep location and surface used, and the reported mechanism or pattern of death. For 1995-1998, we used data on sleep location from an annual survey of randomly selected households of living infants younger than 8 months, collected as part of the National Infant Sleep Position Study at the National Institute of Child Health and Human Development, to calculate risk for death as a result of suffocation in cribs, in adult beds, and on sofas or chairs.

METHODS

The number of reported suffocation deaths by location were compared between the 1980s and 1990s using logistic regression modeling to calculate odds ratios (OR), 95% confidence intervals (CI), and P values. Comparative risks for suffocation deaths on a given sleep surface for infants in the 1990s were examined by calculating rates of death per 100 000 exposed infants and comparing the 95% CI for overlap.

RESULTS

From the 1980s, 513 cases of infant suffocation were considered; from the 1990s, 883 cases. The number of reported suffocation deaths in cribs fell from 192 to 107, the number of reported deaths in adult beds increased from 152 to 391, and the number of reported deaths on sofas or chairs increased from 33 to 110. Using cribs as the reference group and adjusting for potential confounders, the multivariate ORs showed that infant deaths in adult beds were 8.1 times more likely to be reported in the 1990s than in the 1980s (95% CI: 3.2-20.3), and infant deaths on sofas and chairs were 17.2 times more likely to be reported in the 1990s than in the 1980s (95% CI: 5.0-59.3). The sleep location of a subset of cases from the 1990s, 348 infants younger than 8 months at death, was compared with the sleep location of 4220 living infants younger than 8 months. The risk of suffocation was approximately 40 times higher for infants in adult beds compared with those in cribs. The increase in risk remained high even when overlying deaths were discounted (32 times higher) or the estimate of rates of bedsharing among living infants doubled (20 times higher).

CONCLUSIONS

Reported deaths of infants who suffocated on sleep surfaces other than those designed for infants are increasing. The most conservative estimate showed that the risk of suffocation increased by 20-fold when infants were placed to sleep in adult beds rather than in cribs. The public should be clearly informed of the attendant risks.