High incidence of sudden infant death syndrome among northern Indians and Alaska natives compared with southwestern Indians: possible role of smoking.

Epidemiologic studies of sudden infant death syndrome (SIDS) in the United States have found a particularly high incidence among American Indians and Alaska Natives compared with whites. This report shows that there is a remarkable difference in the incidence of SIDS between Northern Indians and Southwestern Indians. From 1984 through 1986, the incidence of SIDS was 4.6 per 1,000 live births among Indians and Alaska Natives in the Northern region of the United States, while the incidence among Southwestern Indians was 1.4 per 1,000 live births (risk ratio = 3.4; 95 percent confidence interval = 2.4-4.8). Among whites living in the same regions, the incidence of SIDS was 2.1 and 1.6 per 1,000 live births, respectively. The incidence among Native Americans in the Northern region was high in all five Indian Health Service Areas. Differences in socioeconomic status, maternal age, birth weight, and prenatal care did not appear to explain the higher incidence of SIDS among Northern Indians compared with Southwestern Indians. However, the prevalence of maternal cigarette smoking during pregnancy is exceptionally high among Northern Indians and Alaska Natives, while it is low among Southwestern Indians. This difference in smoking habits may explain, at least in part, the excess risk of SIDS among Indians in the Northern region. This report points to the need for effective smoking cessation programs for Native Americans, targeting in particular women of reproductive age.