Breast-feeding, dietary intakes and their associations with subclinical vitamin A deficiency in children in Anhui Province, China.

OBJECTIVE This study aimed to explore the associations between breast-feeding, dietary intakes and other related factors and subclinical vitamin A deficiency (SVAD) in children aged 0-5 years in an area in China where mild vitamin A deficiency (VAD) is found. METHODS Data were from a population-based cross-sectional study with 1052 children aged 0-5 years. SVAD cases were identified by the indicator of serum retinol<or=20 microg dl(-1). Breast-feeding status, dietary intakes and other factors were collected through a pre-designed questionnaire. RESULTS The prevalence of SVAD in children aged 0-5 years was 6.9%. Logistic regression analysis showed that the odds ratio of SVAD for breastfeeding was 3.56 (95% confidence limits (95% CL) 2.17-5.82). After adjustment for sex, age in categories, residence, mother's education, mother's occupation, vitamin A preparation supplements, rank in siblings and diarrhoea, the odds ratio for breast-feeding fell to 2.38 (95% CL 1.13-4.95). The odds ratios for breast-feeding within children aged 1 year were 5.46 (95% CL 2.07-15.03) and 4.6 (95% CL 1.72-12.82) before and after adjustment of other confounders, respectively. The odds ratios for breast-feeding did not show statistical significance within children aged 0 or 2 years. The odds ratios decreased, but remained statically significant after further adjustments for individual dietary factor or all dietary factors. CONCLUSION Breast-feeding was a risk factor of SVAD for children, especially for those aged 1 year. The differences in dietary intakes and other established risk factors could not fully explain the increased risk. This finding implies that prolonged breast-feeding alone may not ensure protection of children from VAD in an area with mild SVAD.