Breastfeeding and cardiovascular mortality: the Boyd Orr cohort and a systematic review with meta-analysis

Eur Heart J. 2004 May;25(9):778-86. doi: 10.1016/j.ehj.2004.02.006.


Aims: To investigate the association of breastfeeding with all-cause, cardiovascular, and ischaemic heart disease mortality.

Methods and results: A long-term follow-up of 4999 children originally surveyed from 1937 to 1939 was undertaken (Boyd Orr cohort). Four thousand three hundred and seventy-nine subjects (88%) were traced in adulthood and 3555 (71%) had complete data on all covariates. The results were combined with a meta-analysis of the published literature. In the Boyd Orr study, there was little evidence that breastfeeding was associated with all-cause (hazard ratio: 1.04 [95% CI: 0.90-1.20]), cardiovascular (1.04 [0.83-1.30]), or ischaemic heart disease (1.02 [0.77-1.36]) mortality, compared with bottle-feeding. Meta-analyses of observational studies showed little evidence of an association of breastfeeding with all-cause (pooled rate ratio: 1.01 [95% CI: 0.91-1.13]) or cardiovascular (1.06 [0.94-1.20]) mortality. There was a moderate-to-high degree of between-study heterogeneity for the association between breastfeeding and ischaemic heart disease mortality (I2 value-indicating the degree of between-study variation attributable to heterogeneity-66%), and estimates were consistent with both an important beneficial or adverse effect of breastfeeding.

Conclusion: There is little consistent evidence that breastfeeding influences subsequent all-cause or cardiovascular disease mortality. Results from other well-designed cohorts may clarify residual uncertainty.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Breast Feeding*
  • Cardiovascular Diseases / mortality*
  • Cause of Death
  • Child, Preschool
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Infant
  • Male
  • Myocardial Ischemia / mortality
  • Rural Health
  • Urban Health