Residential mobility and sudden infant death syndrome.

OBJECTIVE

To examine whether permanent domicile change of the mother, thence the infant, or temporary relocation of the infant away from his or her usual place of residence affects the risk of sudden infant death syndrome (SIDS).

DESIGN

A case-control nation-wide epidemiological study.

SETTING

New Zealand between the years 1987-90.

PARTICIPANTS

From the 485 SIDS diagnoses over this time, parents of 393 (81%) SIDS infants consented to participate and these comprise the cases. Controls were selected by randomly sampling 1800 infants from all babies born over 78% of the country. Parents of 1592 (88%) control infants participated.

RESULTS

Infants away from their usual address were 1.70 (95% CI: 1.09, 2.66) times more likely to die from SIDS than infants sleeping at home, after controlling for likely confounding factors. A partial explanation for this finding was that SIDS infants were less likely to have been mainly breast fed in the last two days and were less likely to have shared a room with at least one adult at the nominated sleep/death. Infants of mothers who shifted house after their birth, infants having mothers who shifted house within a year prior to the study interview date, and infants who slept at numerous different houses were associated with an increased relative risk for SIDS at the univariate level, but not after adjustment.

CONCLUSIONS

Infants are less likely to die in their accustomed residential environment. This finding needs confirmation by other studies.