Respiratory disease is the leading cause of hospitalization among young children and results in significant health care expenditure. Young children who develop severe respiratory disease have a 10-fold increase in risk for developing childhood asthma. Recent studies examining the potential benefits of breast-feeding in reducing the incidence of respiratory disease have produced uncertain results. In developing countries, breastfeeding has been shown to reduce the risk of acute infectious illnesses, but the potential benefit of this practice in healthy infants with high standards of living has not been established. Current recommendations from the Surgeon General and the American Academy of Pediatrics state that children should be breastfed exclusively for the first six months. According to current estimates, only 31 percent of women in the United States are continuing to breastfeed until six months of age. Bachrach and colleagues studied the impact of breastfeeding on the risk for hospitalization for lower respiratory tract disease in healthy full-term infants with access to modern medical care.

The data sources for the study included MEDLINE, the OVID databases, Dissertation Abstracts Online, BIOSIS, and personal communications with researchers. Studies were reviewed if they concerned breastfeeding exposure and lower respiratory tract disease hospitalization rates in a developed country. The studies had to include infants living in affluent regions who had a minimum of two months of exclusive breastfeeding versus no breastfeeding, and had to exclude sick, premature, and low-birth-weight infants. Of the 33 studies that were reviewed as primary sources, seven met all of the inclusion criteria and were pooled separately. These seven studies included data for 4,525 infants.

The data from all 33 studies indicated that infants who were breastfed had fewer hospitalizations for lower respiratory tract disease than infants who had not been breastfed. When the data from the seven studies were compared, the summary risk of hospitalization for lower respiratory tract disease was significantly lower in infants who were breastfed than in those who were not. The authors also analyzed data from the various studies to examine the impact of socioeconomic status and exposure to smoking on hospitalization rates for lower respiratory tract disease. They found that these two factors did not account for the positive benefit of breastfeeding.

The authors conclude that healthy infants in developed countries who are not breastfed have three times the risk for hospitalization for lower respiratory tract disease than infants who were breastfed exclusively for at least four months. They add that if social policies were developed to support women in breastfeeding beyond the newborn period, a substantial amount of health care savings would occur.

editor's note: Multiple studies have shown the benefit that breastfeeding provides infants. Despite these results, only a small number of women breastfeed beyond the first six weeks. There are substantial barriers to maintaining breastfeeding, including the need to work outside the home. The study by Bachrach and colleagues has shown that breastfeeding with no supplementation for at least four months has a significant positive effect on infants. However, a significant change has to occur in the working environments of the majority of women before they will be encouraged to breastfeed beyond the first six weeks. As the authors note, the reduction in the number of hospitalizations related to respiratory tract infections as a result of breastfeeding through the first four months would provide substantial savings in health care expenditures. This savings would more than offset the cost of making changes to the work environment.—k.e.m..