Abstract â–¡ 158

It has been reported that head covering by blankets during sleep is a significant risk factor for Sudden Infant Death Syndrome (SIDS). In order to determine if this was a risk factor among a U.S. sample, date from the Chicago Infant Mortality Study were analyzed. This study used a case-control design to examine risk factors for SIDS among Chicago infants who died from SIDS between November 1993 and April 1996. There were 260 SIDS cases with autopsy, death scene investigation and medical record review, each matched to one living control infant on race, age and birth weight. The majority (75%) of SIDS infants were African American, followed by 14% White Hispanic, 9% White, non-Hispanic and 2% other. The mean age of these infants was 89 days (±58); 4% were very low birth weight and 24% were low birth weight. There were 36 SIDS infants who were found with their head or face covered (FHCov) with bedding: 17 head only, 9 face only and 10 head and face. Among the matched controls, 13 had their head or face covered: 10 head only, 1 face only and 2 head and face. The type of coverings were predominantly thin blankets or sheets with only 1 comforter each among cases and controls. FHCov was associated with an increased risk for SIDS: odds ratio (OR) 2.9, 95% confidence interval (CI) 1.5, 5.6. Adjustment for maternal education, marital status and prenatal care did not significantly change this association (OR 2.6, CI 1.3, 5.6). The risk associated with face covering alone (adjusted OR 3.2, CI 0.3, 30.6) was greater than for head covering alone (adjusted OR 2.2, CI 0.9, 5.6), but due to small numbers the confidence intervals included one and were wide. In multivariate models including prone sleep position, soft sleep surface and bed sharing, the independent influence of FHCov was assessed, resulting in an adjusted OR of 1.4, CI 0.6, 3.7 while the odds ratios for the other factors were all greater than one and significant. Next, factors associated with the risk for face or head covering were assessed. Among the 36 SIDS infants with their face or head covered, 67% were sleeping on mattresses, 19% on sofas, 8% in infant carriers and 3% in their mother's arms, while among those without FHCov, the respective proportions were 82%, 9%, 1% and 0.9%. In multivariate modeling, with FHCov as the dependent variable and cases and controls combined, the following factors were found to be associated with FHCov: soft sleep surface (OR 2.4, CI 1.1, 5.0); wrapping (OR 7.2, CI 2.5, 20.2); 2 covers (OR 2.1, CI 0.8, 5.6); and 3 covers (OR 4.3, CI 1.1, 16.4). Again, due to small numbers, confidence intervals were side. Prone position had an OR of 1.9 but was not significant (CI 0.9, 4.2). In conclusion, head or face covering was found to be a risk factor for SIDS in this study. Sleep conditions associated with FHCov were more than one blanket, wrapping, and soft sleep surface. Head and face covering should be avoided in order to further reduce the risk for SIDS.

Funded by the National Institutes of Health (NO1-HD-3-3188) and the Centers for Disease Control and Prevention (U50/CCU300860-06).