The expected impact of a smoking cessation program for pregnant women on infant mortality among Native Americans.

To quantify the expected impact of a smoking cessation program for pregnant women on infant mortality among Native Americans, we estimated the proportional reduction (impact fraction) and the absolute reduction (impact risk) in neonatal and postneonatal mortality as a result of the intervention program. The estimated attributable fraction due to maternal smoking was 16.6% of infant deaths in the Aberdeen Indian Health Service (IHS) Area, 16.2% in the Alaska IHS Area, and 5.2% in the Navajo IHS Area. Under the assumptions that 14% of the smokers participating in a smoking cessation program would quit and that the intervention would have 60% relative efficacy in preventing infant deaths attributable to smoking, the impact fraction was estimated to be 0.9% of all infant deaths in the Aberdeen Area, 1.0% in the Alaska Area, and 0.3% in the Navajo Area. Under the "best" model assumptions (28% cessation rate and 90% relative efficacy), 2.6% of all infant deaths, 3.7% of postneonatal deaths, and 1.2% of neonatal deaths would be prevented by a smoking cessation program in the Aberdeen Area. When applied to 1984-1986 infant mortality data, the impact risk per 100,000 live births under the "best" model assumptions was 10 neonatal deaths and 41 postneonatal deaths in the Aberdeen Area, 10 neonatal and 34 postneonatal deaths in Alaska, and 2 neonatal and 8 postneonatal deaths in the Navajo Area. This report points to the need to develop effective smoking cessation programs for Native Americans, targeted in particular to women of reproductive age.