Iron status biomarkers and C-reactive protein in children aged 19 to 72 months in Chile.

BACKGROUND: The Chilean Ministry of Health has combated iron deficiency through the delivery of fortified milk by the National Complementary Feeding Program (NCFP).

OBJECTIVE: To assess iron status and associations between biomarkers of iron status and serum C-reactive protein (CRP) in 218 beneficiaries of the NCFP aged 19 to 72 months in Santiago and Valparaiso, Chile.

METHODS: Blood was collected from a cross-sectional representative sample. Iron status (measured by hemoglobin, zinc protoporphyrin, and serum ferritin levels) and inflammation (according to CRP level) were determined.

RESULTS: Serum CRP level was positively associated with serum ferritin and zinc protoporphyrin levels (r = 0.16 and r = 0.15; p = .0168 and p = .0290, respectively). Serum ferritin was higher among children with high CRP (> 10 mg/dL) than among those with low CRP (< or = 10 mg/dL) (p = .003). After adjustment for 10, 6, and 5 mg/L CRP, the prevalence of low serum ferritin changed from 56.4% without adjustment to 60.6%, 61.5%, and 42.7%, respectively, and the prevalence of high zinc protoporphyrin changed from 22.9% to 21.6%, 17.4%, and 17.9%, respectively. There were no differences between regions in biomarkers of iron status. There was no association between consumption of fortified milk and the prevalence of abnormal serum ferritin (< 15 microg/L) after adjustment for sex, age, and breastfeeding (OR, 1.00; 95% CI, 0.99 to 1.01; p = .288). After adjustment for 10 mg/L CRP, 5.5% were classified as having iron-deficiency anemia, 42.7% as having iron-deficiency erythropoiesis, 17.9% as having depleted iron stores, and 35.8% as having normal iron status. CONCLUSIONS. CRP level was positively associated with: serum ferritin and zinc protoporphyrin levels. Chilean children aged 19 to 72 months from Santiago and Valparaiso who were beneficiaries of the NCFP had a low prevalence of iron-deficiency anemia, a high prevalence of iron-deficiency erythropoiesis, and a moderate prevalence of depleted iron stores.