Adequacy of micronutrient intakes and status of breastfed Indonesian infants fed traditional complementary foods in Sumedang district, West Java: a longitudinal study

Abstract

Stunting among under-five children in Indonesia is common, raising public health concerns. Inappropriate complementary feeding (CF) practices may compromise optimal growth during late infancy in Indonesia. Hence, it is not surprising that earlier biomarker studies in Indonesia have documented deficiencies of iron, zinc, vitamin A, and anaemia during infancy. Of these deficiencies, nutritional iron deficiency (ID) has been assumed to be the major factor causing the high rates of anaemia during infancy and early childhood in Indonesia.

Therefore, we conducted a prospective, longitudinal study to evaluate complementary feeding, growth, biomarkers of micronutrient status, together with potential non-nutritional confounding factors including parasitic infections, inflammation, and genetic haemoglobin (Hb) disorders among breastfed infants aged 6 to 12 months of age. The study was conducted between August 2013 and August 2014. Infants were randomly selected from all the villages (n=30) in Tanjungsari, Sukasari, and Pamulihan sub-districts in Sumedang district, West Java. We enrolled breastfed infants at 6 months of age (n=230); and followed them at 9 (n=202) and 12 months of age (n=190).

Relationships at 9 months between WHO IYCF indicators, five sentinel foods, micronutrient intakes and subsequent growth at 12 months were explored using multiple linear regression. Then we measured serum biomarkers of iron, zinc, vitamin A, and selenium status adjusted for inflammation with C-reactive protein (CRP) and -1-glycoprotein (AGP) to determine the proportion with micronutrient deficiencies at aged 6, 9 and 12 months. Next, we performed multiple regression and logistic regression analysis to examine multivariate relationships between haemoglobin and anaemia, respectively, and infant micronutrient status, household, maternal, and infant non-nutritional factors

Our results showed that stunting increased from 15.8% at 6 months to 22.6% at 12 months. Median intakes of energy, niacin, calcium, iron, and zinc from complementary foods were consistently below WHO estimated needs. Infants consuming fortified infant foods (FIFs) at 9 months had diets with a lower dietary diversity score (2.3 vs. 3.0) and energy density, with lower median intakes of energy (250 vs. 310 kcal/d) and protein (6.5 vs. 9.1 g/d) from complementary foods than non-consumers (P<0.01), despite higher intakes of calcium, iron, and vitamins A, and C (P<0.001). Positive relations existed for the consumption of FIFs alone at 9 months with both length-for-age z-score (LAZ) and weight-for-age z-score (WAZ) at 12 months.

At 6, 9, and 12 months of age, the new BRINDA regression adjustment for inflammation yielded the highest proportion with iron deficiency (20.3, 37.8, 59.5%) and the lowest proportion with both vitamin A (26.4, 16.6, 17.3%) and zinc (16.9, 20.6, 11.0%) deficiency, respectively, compared to unadjusted estimates. For serum selenium, irrespective of adjustment, the proportion with deficiency was high (>50%) across all ages. The proportion of infants with anaemia increased from 32.9% to 38.4%% at age 6 and 12 months of age, which was negatively associated with ferritin at 6 (odds ratio (OR): 0.46 [95% CI: 0.28, 0.76]) and 12 months of age (OR: 0.25 [95% CI: 0.12, 0.49]), respectively. In addition, female sex, and lower CRP concentrations were associated with higher haemoglobin concentrations at 6 months of age; whereas serum folate was a significant negative predictor of anaemia at 12 months (OR: 0.96 [95% CI: 0.92, 0.99]).

In conclusion, our findings highlight the inadequate CF practices in Indonesia. Without inflammation adjustment, iron deficiency was grossly under-estimated and vitamin A and zinc deficiency over-estimated, highlighting the importance of correcting for the influence of inflammation prior to implementing programmes to alleviate micronutrient malnutrition. Anaemia remains a persistent and severe public health problem during infancy in Sumedang district, Indonesia, of which low iron status is a major predictor at 6 and 12 months of age, although at age 12 months, folate also had a role in the anaemia. Hence, there is an urgent need to improve CF practices during the latter half of infancy in the study setting and re-evaluate the performance of iron deficiency control programs in this district.