Breast feeding and vitamin A deficiency among children attending a diarrhoea treatment centre in Bangladesh: a case-control study

Abstract

Objective: To determine the effect of breast feeding on the risk of xerophthalmia in children aged 6 months to 3 years attending a diarrhoea treatment centre in Bangladesh.

Design: Case-control study based on stratified analysis (Mantel-Haenszel) and multivariate analysis (logistic regression) of data from a treatment centre based surveillance system.

Setting: A large diarrhoea treatment centre in Dhaka, Bangladesh.

Patients: 2687 children aged 6 months to 3 years representing a 4% systematic sample of all children in this age group treated yearly at the centre over three consecutive years. 66 of the children were cases of xerophthalmia (that is, they had Bitot's spots or corneal lesions or night blindness or night blindness plus conjunctival xerosis or any combination of these) and the remaining 2621 did not have signs or symptoms of vitamin A deficiency. This second group served as controls.

Main outcome measure: Xerophthalmia and breast fed at onset of diarrhoea or presentation.

Results: The odds ratio relating breast feeding to vitamin A deficiency after adjustment for a large number of confounding variables (0.26 (95% confidence interval 0.14 to 0.49); p less than 0.001) reflected a 74% reduction in the risk of vitamin A deficiency among breast fed children. The estimated reduction of risk did not decline with age, and some 49% of children aged 24-35 months were still being breast fed. The odds ratio relating breast feeding to xerophthalmia in the third year of life (0.35 (95% confidence interval 0.35 to 0.86) reflected a 65% reduced risk of vitamin A deficiency. Other important risk factors or prognostic indicators for xerophthalmia as identified by multivariate analysis were recent measles, prolonged diarrhoea, severe protein energy malnutrition, and poor socioeconomic state.

Conclusions: These results indicate that breast feeding was associated with a substantial reduction of the risk of vitamin A deficiency extending to the third year of life and support the recommendation that mothers in developing countries should be advised to breast feed for as long as possible.

PIP: The objective of this study was to determine the effect of breastfeeding on the risk of xeropthalmia in children ages 6 months-3 years attending a diarrhea treatment center in Bangladesh. Dhaka, Bangladesh was the scene of this case-control study based on stratified analysis (Mantel-Haenszel) and multivariate analysis (logistic regression) of data from a treatment center-based surveillance system. 2687 children who represented a 4% systematic sample of all children in this age group were treated yearly at the center over 3 consecutive years. 66 of the children exhibited cases of xerophthalmia (they had Bitot's spots or corneal lesions or night blindness or night blindness plus conjunctival xerosis or any combination of these) and the remaining 2621 did not have signs or symptoms of vitamin A deficiency. This 2nd group served as the control group. The odds ratio relating breastfeeding to vitamin A deficiency after adjustment for a large number of confounding variables (0.26 [95% confidence interval 0.14-0.49]; p0.001) reflected a 74% reduction in the risk of vitamin A deficiency among breastfed children. The estimated reduction of risk did not decline with age, and some 49% of the children ages 24-35 months were still being breastfed. The odds ratio relating breastfeeding to xerophthalmia in the 3rd year of life (0.35 [95% confidence interval 0.35-0.86] reflected a 65% reduced risk of vitamin A deficiency. Other important risk factors or prognostic indicators for xerophthalmia as identified by multivariate analysis were recent measles, prolonged diarrhea, severe protein energy malnutrition, and poor socioeconomic status. These results indicate that breastfeeding was associated with a substantial reduction of risk for vitamin A deficiency extending to the 3rd year of life. The author supports the recommendation that mothers in developing countries should breastfed for as long as possible.