SMOKING AND THE SUDDEN-INFANT-DEATH-SYNDROME

Objective. Maternal smoking has been shown to be a risk factor for sud den infant death syndrome (SIDS). The effect of smoking by the father and other household members has not previously been examined. Methods. A large nationwide case-control study. Four hundred eighty-five SIDS deaths in the postneonatal age group were compared with 1800 control i nfants. Results. Infants of mothers who smoked during pregnancy had a 4.09 (95% confidence interval [CI] = 3.28, 5.11) greater risk of death than infants of mothers who did not smoke. Infants of mothers who smo ked postnatally also had an increased risk of SIDS compared with infan ts of nonsmokers and, furthermore, the risk increased with increasing levels of maternal smoking. Smoking by the father and other household members increased the risk (odds ratio [OR] = 2.41, 95% CI = 1.92, 3.0 2 and OR = 1.54, 95% CI = 1.20, 1.99, respectively). Smoking by the fa ther increased the risk of SIDS if the mother smoked, but had no effec t if she did not smoke. In analyses controlled for a wide range of pot ential confounders, smoking by the mother and father was still signifi cantly associated with an increased risk of SIDS. Conclusion. Passive tobacco smoking is causally related to SIDS.