ABSTRACT
BACKGROUND: Anemia during infancy in Indonesia is common, with iron deficiency (ID) assumed to be the major cause. Other micronutrients besides iron may have a role in determining hemoglobin (Hb) but have not yet been explored in Indonesia. OBJECTIVE: We investigated 7 micronutrient biomarkers and selected nonnutritional factors as potential predictors of Hb and anemia at ages 6, 9, and 12 mo in a cohort of Indonesian infants at risk of coexisting micronutrient deficiencies. METHODS: Apparently healthy breastfed infants were randomly selected from birth registries at 6 mo (n = 230) and followed-up at 9 mo (n = 202) and 12 mo (n = 190). Hb, serum micronutrient biomarkers-iron [as ferritin and serum soluble transferrin receptor (sTfR)], zinc, selenium, folate, vitamin A [as retinol-binding protein (RBP)], vitamin B-12, and vitamin D (as 25-hydroxyvitamin D) (adjusted for inflammation, where appropriate)-and maternal sociodemographic status, health, BMI, heminthiasis, and selected Hb genetic disorders were measured. Multivariate analysis examined relations between micronutrient biomarkers and nonnutritional factors (except helminthiasis and genetic Hb disorders) with Hb and anemia at 6 and 12 mo. RESULTS: ID (based on ferritin) was a predictor of lower Hb and anemia at both 6 and 12 mo of age (P < 0.02). Additional predictors at 6 mo were tertiary education and higher maternal Hb for higher Hb, sex (being male) and inflammation (P < 0.05) for both lower Hb and anemia, and greater maternal height (P = 0.036) for anemia only. At 12 mo, a significant biomarker predictor besides ID was RBP (P = 0.035) for Hb. CONCLUSION: ID was a major contributor to lower Hb and anemia, although RBP was also associated.
ABSTRACT
Inflammation confounds the interpretation of several micronutrient biomarkers resulting in estimates that may not reflect the true burden of deficiency. We aimed to assess and compare the micronutrient status of a cohort of Indonesian infants (n 230) at aged 6, 9 and 12 months by ignoring inflammation (unadjusted) and adjusting four micronutrient biomarkers for inflammation with C-reactive protein (CRP) and α-1-glycoprotein (AGP) using the following methods: (1) arithmetic correction factors with the use of a four-stage inflammation model; and (2) regression modelling. Prevalence of infants with any inflammation (CRP>5 mg/l and/or AGP>1 g/l) was about 25% at each age. Compared with unadjusted values, regression adjustment at 6, 9 and 12 months generated the lowest (P50 % across all ages. In conclusion, without inflammation adjustment, Fe deficiency was grossly under-estimated and vitamin A and Zn deficiency over-estimated, highlighting the importance of correcting for the influence of such, before implementing programmes to alleviate micronutrient malnutrition. However, further work is needed to validate the proposed approaches with a particular focus on assessing the influence of varying degrees of inflammation (i.e. recurrent acute infections and low-grade chronic inflammation) on each affected nutrient biomarker.
