Ethnic differences in the sudden infant death syndrome: what we can learn from immigrants to the UK

To compare the effect of potential maternal and birth factors on rates of sudden infant death syndrome (SIDS) within and between infants born to mothers of different ethnic groups.

Routinely collected obstetric, child health data relating to 39,101 residents of three East London Districts born in 1989-1990 were obtained. These were matched with 312 death registration records to validate death and add registered cause of death. Mortality rates were calculated in the usual way, and using life-table methods.

These related to six ethnic groups, the largest of which were Anglo-European and Bangladeshi. Low birth-weight was the only factor associated with a greater risk of SIDS in all ethnic groups. Maternal smoking was uncommon amongst all Asian groups and African mothers, and rates of SIDS were uniformly low amongst non-smokers in all ethnic groups except Pakistanis. Adjustment for maternal age, parity, gestational age and birthweight would widen the differences between risk of SIDS observed between Anglo-Europeans and Bangladeshi infants.

The study has demonstrated that local data is more timely and of greater detail than that available nationally. Of the risk factors considered, smoking reported during pregnancy is the most commonly encountered and is particularly associated with deaths attributed to SIDS.