Vitamin A deficiency and determinants of vitamin A status in Bangladeshi children and women: findings of a national survey

Objective: Using data from the national micronutrients survey 2011-2012, the present study explored the status of subclinical vitamin A nutrition and the underlying determinants in the Bangladeshi population. Design: A nationwide cross-sectional study. Settings: The survey covered 150 clusters; fifty in each of rural, urban and slum strata. Subjects: Three population groups: (i) pre-school age children (6-59 months; PSAC); (ii) school age children (6-14 years; SAC); and (iii) non-pregnant nonlactating women (15-49 years; NPNLW). Results: National prevalence of subclinical vitamin A deficiency was 20.5, 20.8 and 5.3% in PSAC, SAC and NPNLW, respectively. Slum populations had higher prevalence compared with urban (PSAC: 38.1 v. 21.2%, P < 0.001; SAC: 27.1 v. 22.1%, P = 0.004; NPNLW: 6.8 v. 4.7%, P = 0.01). Dietary vitamin A met up to 27.1-46.0% of daily needs; plant-source vitamin A constituted 73-87% of the intakes. Multivariable regression analyses showed that higher consumption of animal foods was associated with higher retinol status in PSAC (beta = 0.27; P < 0.001); and living in urban area was related to higher retinol status in NPNLW (beta = 0.08, P = 0.004) and PSAC (beta = 0.11, P = 0.04). Increased intake of leafy vegetables was associated with lower retinol status in SAC (beta = -0.08, P = 0.02). Vitamin A supplementation in PSAC did not significantly influence serum retinol within one year post-supplementation (P>0.05 for differences in beta between < 3 months v. 3-6 months, 6-9 months and 9-12 months). Conclusions: Prevalence of subclinical vitamin A deficiency was high in children in Bangladesh. Intakes of animal-source foods and leafy vegetables were associated with higher and lower retinol status, respectively. Increased food diversity through animal-source foods is required.