The effect of the systemic inflammatory response on plasma zinc and selenium adjusted for albumin.

Background & Aim: The magnitude of systemic inflammatory response, as evidenced by C-reactive protein (CRP), is a major factor associated with lower zinc and selenium. They may also be influenced by their binding proteins, such as albumin. The aim of the present study was to examine the relationships between plasma zinc, selenium and the systemic inflammatory response in a large cohort of patients referred for nutritional screen and also to examine these relationships in patients with critical illness.

Methods: Patients referred for nutritional assessment of zinc (n = 743) and selenium (n = 833) and 114 patients with critical illness were examined. Intra-assay imprecision was <10% for these analytes.

Results: In the nutritional screen cohort, plasma zinc was significantly associated with CRP (rs = -0.404, p < 0.001) and albumin (rs = 0.588, p < 0.001). For each CRP category (≤10, 11-80, >80 mg/l) the zinc/albumin ratio x100 was similar (31, 33 and 32 respectively, p = 0.029). Plasma selenium was significantly associated with CRP (rs = -0.489, p < 0.001) and albumin (rs = 0.600, p < 0.001). With increasing CRP category (≤10, 11-80, >80 mg/l) the selenium/albumin ratio ×100 was lower (2.3, 2.1 and 1.8 respectively, p < 0.001). Similar relationships were also observed in the cohort of patients with critical illness.

Conclusion: Plasma zinc was associated with both CRP and albumin. The impact of the systemic inflammatory response could be largely adjusted by albumin concentrations. Plasma selenium was associated with both CRP and albumin. The impact of the systemic inflammatory response on plasma selenium concentrations could not be reasonably adjusted by albumin concentrations.