PUBLIC-HEALTH POLICY ON BED SHARING AND SMOKING IN THE SUDDEN-INFANT-DEATH-SYNDROME

Aims. Further develop New Zealand public health policy on infant bed s haring by quantifying the number of sudden infant death syndrome (SIDS ) cases attributable to bed sharing among infants of smoking and nonsm oking mothers. Methods. A large nation-wide case control study coverin g a region with 78% of all births in New Zealand during 1987-90. Inter views were completed with parents of 393 (81.0% of total) cases who di ed from the sudden infant death syndrome in the postneonatal age group , and 1592 (88.4% of total) controls who were a representative sample of all hospital births in the study region. Results. The proportion of control infants who usually bed shared in the last 2 weeks was 65.7% in Maori, 73.7% in Pacific Island people and 35.5% in Europeans (44.5% in all ethnic groups combined, and half of these for less than 2 hour s per night). There was an interaction between maternal smoking and in fant bed sharing on the risk of sudden infant death separately in Maor i, Pacific Island and European infants with the risk being highest in infants exposed to both risk factors. 26% of SIDS deaths were explaine d by bed sharing among infants of smoking mothers (who comprised 16% o f the total infant population) and 3% by bed sharing among infants of non-smoking mothers (28% of total infant population). Conclusion. Infa nt bed sharing is common. The majority of SIDS deaths that are attribu ted to bed sharing occur among infants of smoking mothers. A policy wh ich advises all infants not to bed share is estimated to potentially s ave an extra 3% of SIDS compared to a policy targeted only on infants of smoking mothers. If public attitudes are favorable to bed sharing, there could be a marginal cost (against its acceptance) by including i nfants of non-smoking mothers in the recommendation not to bed share. These findings should not be interpreted as indicating that bed sharin g where the mother is a nonsmoker is safe or protective against SIDS.