Cost differences between low birth weight attributable to smoking and low birth weight for all causes

Background. Low birthweight (<2,500 g) is one of the major predictors of infant mortality. The clinical salience of low birthweight depends on its severity. The impact of smoking on low birthweight is greater in the 1,500-2,499-gm category than below 1,500 gm. This has an important implication for economic analyses of smoking cessation programs for pregnant women. Because health care cost is closely associated with birthweigh, the cost of low birthweight attributable to smoking may be different than the average cost of low birthweight for all causes. Little is known about such cost differences. Methods. The population-attributable risk was used to estimate the number and percentage of low-birthweight infants due to maternal smoking. Costs by birthweight groups were used to determine cost differences between low birthweight due to smoking and for all causes. Results. The net incremental costs per low birthweight due to smoking range from $4,256 to $8,640 compared to the costs of $5,213 to $10,306 per low birthweight by all causes. The cost differences may be up to 18%. Conclusion. Considerably lower costs at birth were found in low birthweight due to smoking than for all causes. The cost difference was attributable to the difference in the severity of low birthweight.