Micronutrient Deficiencies and Anemia in Children in Mexico: Results From the National Health and Nutrition Survey (ENSANUT)

Abstract

ObjectivesTo examine the burden of anemia and micronutrient deficiencies, and associations between micronutrient status and anemia in children (1–11 y) in Mexico. MethodsData from the National Health and Nutrition Survey (ENSANUT 2018) were analyzed to determine the burden of anemia and micronutrient deficiencies (iron, vitamin B12, vitamin A) in a nationally-representative sample of 4,891 children 1 to 11 years of age (1 to < 5 y: 1,337; 5–11 y: 3,554). Hemoglobin (Hb) was measured via HemoCue and venous blood samples were collected, processed, and stored at < -80°C until analysis. Serum ferritin (SF), C-reactive protein (CRP) and vitamin B12 concentrations were measured via immunoassays. Serum retinol was measured via HPLC. Hemoglobin was adjusted for altitude; anemia (< 5 y: Hb < 11.0 g/dL; 5–11 y: < 11.5 g/dL) and iron deficiency (ID; < 5 y: < 12.0 μg/L; 5–11 y: < 15.0 μg/L) were defined using age-specific cut-offs. Iron insufficiency was defined as SF < 20.0 μg/L, and inflammation as CRP > 5.0 mg/L. Vitamin B12 deficiency and insufficiency were defined as < 148 and < 221 pmol/L, and vitamin A deficiency was defined as retinol < 20 μg/dL. Survey linear and logistic regression were used to examine associations of micronutrient biomarkers with hemoglobin concentrations and odds of anemia. ResultsSerum ferritin concentrations (β [SE]: 0.0003, p < 0.001) and serum retinol levels (0.0005, p < 0.001) were associated with higher hemoglobin levels, while iron deficiency (–0.57 [0.03], p < 0.001), iron insufficiency (–0.54 [0.02]; p < 0.001), and vitamin A deficiency (–0.53 [0.01], p < 0.0001) were associated with lower hemoglobin levels. In analyses of anemia, the odds of anemia were 11% lower per 10 μg/L increase in serum ferritin (OR [95% CI]: 0.89 [0.84–0.93], p < 0.001) and 34% lower per 10 μg/dL increase in serum retinol (OR: 0.66 [0.57–0.77], p < 0.001), while iron deficiency (OR: 2.22 [1.49–3.29], p < 0.001) and iron insufficiency (OR: 1.74 [1.32–2.30]; p = 0.0001) were associated with higher odds of anemia. ConclusionsFindings suggest that the burden of anemia and micronutrient deficiencies are high in children in Mexico, and lower iron and vitamin A status were associated with increased odds of anemia. Funding SourcesENSANUT was funded by The Ministry of Health of Mexico.