The descriptive epidemiology of sudden infant deaths among natives and whites in Alaska

From 1976-1980, the incidence of sudden infant deaths among native Alaskans was 2.9 times higher than that for white Alaskans (6.28 per 1,000 live births among natives vs. 2.14 per 1,000 live births among whites). Linked birth and death vital records data were used to compare the age-at-death distributions and relative risks associated with demographic factors for natives and whites. The purpose of the comparisons was to seek clues to the etiology of sudden infant death in natives. The age-at-death distributions for natives and whites were virtually identical (mean age at death 90.4 +/- 7.0 days for natives; 87.8 +/- 6.5 days for whites). The associations between the risk of sudden death and birth weight, marital status, season of birth, and residence were similar for natives and whites. The risk associated with young maternal age (less than 20 years) was significantly higher for whites than for natives (3.20 vs. 1.38). The sex ratio for sudden deaths among whites significantly favored males (relative risk = 1.78; female = reference); a significant sex ratio was not apparent for natives. Vital records data were useful for confirming the native-white difference in sudden infant death incidence, but not for elucidating etiologic differences between natives and whites.