Influence of breastfeeding on retinal vessel calibers in school-age children. The Generation R Study.

BACKGROUND/OBJECTIVES: A shorter breastfeeding duration is associated with an increased risk of cardiovascular disease in adulthood. Early microvasculature structure adaptations may be part of the underlying mechanism. We examined the associations of ever breastfeeding, breastfeeding duration and exclusivity, and the timing of introduction of solid foods with retinal vessel calibers in children.

SUBJECTS/METHODS: We performed a population-based prospective cohort study from fetal life onwards in the city of Rotterdam, the Netherlands. We obtained information on ever breastfeeding, breastfeeding duration and exclusivity, and age at introduction of solid foods from postal questionnaires at the ages of 2, 6 and 12 months after birth. At the median age of 6.0 years (90% range: 5.7-6.8), we measured retinal arteriolar and venular calibers from digitized retinal photographs among 3220 children. Grader-specific s.d. scores (SDS) for both central retinal and arteriolar equivalents were constructed.

RESULTS

We observed that in the models only adjusted for child's age, sex and ethnicity, children who were never breastfed had narrower retinal arteriolar and venular calibers in childhood as compared with children who were breastfed (differences in retinal arteriolar and venular calibers, respectively: -0.16 SDS (95% confidence interval (CI): -0.29, -0.03) and -0.18 SDS (95% CI: -0.32, -0.04)). After additional adjustment for maternal and childhood socio-demographic and lifestyle-related characteristics, never breastfeeding was only associated with narrower retinal venular caliber (difference: -0.15 SDS (95% CI: -0.29, -0.02)). We did not observe associations of breastfeeding duration or exclusivity, or age at introduction of solid foods with retinal vessel calibers.

CONCLUSIONS

Children who were never breastfed tended to have narrower retinal venular calibers. We did not observe associations of breastfeeding duration with retinal vessel calibers. Family-based socio-demographic factors, maternal lifestyle-related factors and childhood factors only slightly influenced the observed associations. These results should be considered a hypothesis generating for further observational and experimental studies.