Purpose: The objective of this study was to investigate an association between spherical refractive error and breastfeeding.
Methods: Strabismus, amblyopia, and refractive errors in Singaporean preschoolers (STARS) is a cross-sectional population-based study of 3009 Chinese children aged 6-72 months conducted between June 2006 and September 2008 in Singapore. Parents were asked about the history of breastfeeding in face-to-face interviews. Children without cycloplegia or without refraction assessment were excluded. The final sample analysed was 2639 children (1375 male, 1264 female).
Results: Out of those who were breastfed, 842 (41.3%) were breastfed for more than 3 months and 599 (29.4%) were breastfed longer than 6 months. The prevalence of myopia, defined as the spherical equivalent refraction of the right eye of at least -0.5 dioptres (D), was 11.3% (95% CI (10.1, 12.5)). The mean spherical equivalent refraction of breastfed children was 0.12 D higher than that of children who were not breastfed (P-value=0.03). Breastfeeding, however, was not associated with myopia (adjusted OR=0.85; 95% CI (0.62, 1.18)).
Conclusions: The results show that breastfeeding is associated with more hyperopic spherical equivalent refraction in young Chinese children in Singapore.