Associations Between Inflammation Biomarkers and Serum Ferritin and Zinc Concentrations in Preschool Children in Nepal

Abstract

Concentration of trace nutrients is affected by inflammation; however, there has been limited research on iron and zinc, particularly in children. The objective of the current was to assess associations between inflammation biomarkers and serum ferritin and zinc concentrations., The study used α-1 glycoprotein (AGP) as a second biomarker because C-reactive protein (CRP) detection as a biomarker for inflammation is less sensitive in chronic infections The study utilized cross-sectional data of 1649 preschool Nepalese children from Nepal National Micronutrient Status Survey 2016. A standardized, highly sensitive technique was used to measure CRP and AGP. To obtain associations between CRP and AGP, nutrient concentrations were stratified across classifications of CRP and AGP. Concentrations level greater and smaller than several CRP and AGP cut-off points, namely, 0.5 mg/L, 1.0 mg/L, 3.0 mg/L and 5.0 mg/L (CRP) and 0.5 mg/L, 1.0 mg/L, 1.5 mg/L and 2.0 mg/L (AGP). With CRP biomarker at interval of > 0.5-1 mg/L, the median (25^th and 75^th percentiles) was 21.6 (11.5, 37.8) mg/L for ferritin; and 83.9 (63.8, 108.8) mg/L for zinc. Corresponding values for ferritin and zinc with AGP biomarker were 22.2 (10.9, 35.9) mg/L and 83.9 (65.6, 106.9) mg/L respectively. CRP concentration at interval of ≥ 5 mg/L was negatively associated with ferritin concentration [adjusted odds ratio (aOR)= 0.44, 95% confidence interval (CI): (0.24, 0.82)]. AGP concentration at interval of ≥ 1.0 mg/L was negatively associated with zinc concentration [aOR: 0.71; 95% CI: (0.50, 1.00)]. High CRP and AGP levels as defined by their low cut-off points (below0.5 mg/L) had no influence on zinc and ferritin concentrations. Using both CRP and AGP as biomarkers for inflammation provides higher precision in the detection of inflammation. This combination of biomarkers is therefore recommended in future research for assessing zinc and iron deficiencies. The negative association of CRP and AGP with serum ferritin and zinc concentrations highlight the need to pay special attention to non-biological factors with elevated levels of the two inflammation biomarkers.