Background: Infectious disease is a leading cause of morbidity and hospitalization for infants and children. During infancy, breast-feeding protects against infectious diseases, particularly respiratory infections, gastrointestinal infections, and otitis media. Little is known about the longer-term impact of breast-feeding on infectious disease in children.
Methods: We investigated the relationship between infant feeding and childhood hospitalizations from respiratory and gastrointestinal infections in a population-based birth cohort of 8327 children born in 1997 and followed for 8 years. The main outcomes were public hospital admissions for respiratory infections, gastrointestinal infections, and all infectious diseases. Cox regression was used to assess time to first hospitalization.
Results: Breast-feeding only (no formula-feeding) for 3 or more months was associated with a lower risk of hospital admission in the first 6 months of life for respiratory infections (hazard ratio = 0.64 [95% confidence interval = 0.42-0.97]), gastrointestinal infections (0.51 [0.25-1.05]), and any infection (0.61 [0.44-0.85]), adjusted for sex, type of hospital at birth, and household income. Partial breast-feeding (both breast-feeding and formula-feeding) in the first 3 months also reduced hospitalizations from infections but with smaller effect sizes. Beyond 6 months of age, there was no association between breast-feeding status at 3 months and hospitalization for infectious disease.
Conclusions: Giving breast milk and no formula for at least 3 months substantially reduced hospital admissions for many infectious diseases in the first 6 months of life, when children are most vulnerable.