ABSTRACT
Objectives: Plasma zinc concentration (PZ) is influenced by many factors leading to over-estimate the real prevalence of zinc deficiency (ZD). This study aimed to assess changes in PZ in 12-59- months-old Senegalese boys and girls after adjusting for the overall known confounding factors. Methods: During a national representative cross sectional survey in Senegal, blood was collected in 583 girls and 568 boys according to procedures recommended by IZiNCG. PZ, CRP and AGP were determined. Published correction factors (Thurnham et al., 2005) were used to adjust PZ to infections. Measured and adjusted values were compared. General Linear Model (GLM) was used to compare PZ changes in girls and boys after adjustment for CRP, AGP, time of blood collection, recent meal and elapsed time from blood draw to centrifugation. Results: Mean PZ were 63.5±14.5 and 63.9±14.3 μg/dL for boys and girls, respectively. PZ was not correlated with CRP, time from last meal to blood draw, but was negatively related to AGP (p <0.0001), time of the sample collection (p <0.001), and was positively related to time between blood draw and centrifugation (P<0.05). After adjusting for infections, PZ increased significantly in boys (66.2±16 μg/dL), and girls (66.5±16 μg/dL), leading to a decreased prevalence of ZD in both sexes without any significant difference. Using GLM, PZ for boys (65.5±3.3) and girls (66.8±3.2) were significantly greater than the measured values (P<0.0001) but were comparable between gender. Conclusions: Blood collection procedures and infection status should be considered during measurement of plasma zinc concentration when assessing zinc status in population.