Impact of micronutrient powder on thiamin, folate and vitamin B12 status in children in rural Laos
Guy-Marino Hinnouho, MD, PhD
Objectives: Whether deficiencies of thiamine, folate, and vitamin B12 (B12) are common in young Laotian children is presently unknown. We evaluated this question and assessed the effects of a daily multiple micronutrient powder (MNP) on thiamine, folate, and B12 status among young Laotian children.
Methods: Children (n=1704) aged 6-23 mo, participating in a double-blind placebo-controlled randomized trial were individually randomized either to MNP (containing 0.5 mg of thiamine, 150 μg folic acid, and 0.9 μg vitamin B12, along with 12 other micronutrients) or placebo group. Children received their assigned supplements daily for ~36 weeks. Information on demographic, socio-economic status, food security, child feeding practices, and child and maternal anthropometric indices were collected at baseline. Venous blood samples were collected at baseline and endline. In a randomly selected sub-sample of 260 children, erythrocyte thiamin diphosphate (eTDP) was determined using the thiochrome reaction coupled with high-performance liquid-chromatography-fluorescence detection (HPLC-FLD); plasma folate and B12 concentrations were assessed using the Roche e411 immunoassay bio analyzer. Linear or modified Poisson regression models were used to assess group differences in continuous and dichotomized outcomes respectively and logistic regression model was used to identify risk factors of children who are deficient in these micronutrients.
Results: At enrollment, mean age was 13.1 ± 4.9 months and 64.6% of the children were anemic (hemoglobin <110 g/L). Baseline mean eTDP, folate, and B12 were 78.5 ± 57.2 nmol/L, 22.2 ± 10.1 nmol/L, and 451.0 ± 180.8 pmol/L respectively and prevalences of deficiencies of thiamine (eTDP <70 nmol/L), folate (plasma folate <10 nmol/L), and B12 (plasma B12 <221 pmol/L) were 58.1%, 8.1%, and 6.2% respectively.
There was no treatment effect on endline thiamine (110.6 ± 8.9 nmol/L in MNP vs. 110.4 ± 8.9 nmol/L in placebo group; p=0.783) and B12 (523.3 ± 24.6 pmol/L in MNP vs. 515.9 ± 24.8 pmol/L in placebo; p=0.678) concentrations. The prevalence of thiamine and B12 deficiencies did not differ significantly between the two groups (33.8% in MNP vs. 34.4% in placebo, p=0.685 and 3.6% in MNP vs. 1.6% in placebo, p=0.503; respectively).
However, endline folate concentration was significantly higher in the MNP group compared to the placebo group (28.2 ± 0.8 nmol/L vs 19.9 ± 0.8 nmol/L, respectively; p<0.001). The prevalence of folate deficiency was significantly lower in the MNP group compared to the placebo group (1.6% vs 17.4%; p=0.015).
Conclusions: Thiamine deficiency was high in this study population while folate and B12 deficiencies were both low. Compared to a placebo, a daily MNP containing 0.5 mg of thiamine, 150 μg of folic acid and 0.9 μg of vitamin B12 along with 12 other micronutrients improved folate but did not change thiamine and B12 status in young Laotian children.
Website Link: http://picn.ucdavis.edu/research/projects/laozinc.html