Regional differences in death rates among postneonatal infants in Kentucky, 1982-1985.

Our objective was to analyze differences in postneonatal mortality rates between the southeastern (Appalachian) region of Kentucky and the remainder of the state to identify factors associated with increased mortality in the Appalachian (AP) region. The relative risk of postneonatal deaths in the AP region when compared with the remainder of Kentucky (KY) was 1.38 (95% confidence interval = 1.15-1.65). Adjustment for birth weight, maternal age, and marital status of the parents had no appreciable effect on the risk ratio; however, adjustment for maternal education negated the increased risk of postneonatal death among the AP region births. When causes of postneonatal death were compared, three specific disease groupings were disproportionately represented among AP infants: Sudden Infant Death Syndrome (SIDS); congenital malformations; and infections. Most striking was the excess risk of infection-related death because it represents a preventable component in the postneonatal mortality excess of the AP region; and, because of the apparent association with maternal "under education." These findings are discussed within a public health intervention context.