Why do children in slums suffer from anemia, iron, zinc, and vitamin a deficiency? Results from a birth cohort study in Dhaka

Considering the high burden of micronutrient deficiencies in Bangladeshi children, this analysis aimed to identify the factors associated with micronutrient deficiencies and association of plasma micronutrient concentration trajectories from 7 to 24 months with the concentrations at 60 months of age. Plasma samples were collected at 7, 15, 24, and 60 months of age, and hemoglobin, ferritin, zinc, and retinol concentrations of 155, 153, 154, and 155 children were measured, respectively. A generalized estimating equation was used to identify the factors associated with micronutrient deficiencies, while latent class growth modeling identified the trajectories of plasma micronutrients from 7 to 24 months and its association with the concentrations of micronutrients at 60 months was examined using multiple linear regression modeling. Early (AOR = 2.21, p < 0.05) and late convalescence (AOR = 1.65, p < 0.05) stage of an infection, low ferritin (AOR = 3.04, p < 0.05), and low retinol (AOR = 2.07, p < 0.05) were associated with increased anemia prevalence. Wasting at enrollment was associated with zinc deficiency (AOR = 1.8, p < 0.05) and birth weight was associated with ferritin deficiency (AOR = 0.58, p < 0.05). Treatment of drinking water was found protective against vitamin A deficiency (AOR = 0.57, p < 0.05). Higher trajectories for ferritin and retinol during 7–24 months were positively associated with plasma ferritin (β = 13.72, p < 0.05) and plasma retinol (β = 3.99, p < 0.05) at 60 months.