Urine selenium concentration is a useful biomarker for assessing population level selenium status

Phiri, Felix P.; Ander, E. Louise; Lark, R. Murray; Bailey, Elizabeth H.; Chilima, Benson; Gondwe, Jellita; Joy, Edward J.M.; Kalimbira, Alexander A.; Phuka, John C.; Suchdev, Parminder S.; Middleton, Daniel R.S.; Hamilton, Elliott M.; Watts, Michael J.; Young, Scott D.; Broadley, Martin R.

Abstract

Plasma selenium (Se) concentration is an established population level biomarker of Se status, especially in Se-deficient populations. Previously observed correlations between dietary Se intake and urinary Se excretion suggest that urine Se concentration is also a potentially viable biomarker of Se status. However, there are only limited data on urine Se concentration among Se-deficient populations. Here, we test if urine is a viable biomarker for assessing Se status among a large sample of women and children in Malawi, most of whom are likely to be Se-deficient based on plasma Se status. Casual (spot) urine samples (n = 1406) were collected from a nationally representative sample of women of reproductive age (WRA, n =741) and school aged children (SAC, n=665) across Malawi as part of the 2015/16 Demographic and Health Survey. Selenium concentration in urine was determined using inductively coupled plasma mass spectrometry (ICP-MS). Urinary dilution corrections for specific gravity, osmolality, and creatinine were applied to adjust for hydration status. Plasma Se status had been measured for the same survey participants. There was between-cluster variation in urine Se concentration that corresponded with variation in plasma Se concentration, but not between households within a cluster, or between individuals within a household. Corrected urine Se concentrations explained more of the between-cluster variation in plasma Se concentration than uncorrected data. These results provide new evidence that urine may be used in the surveillance of Se status at the population level in some groups. This could be a cost-effective option if urine samples are already being collected for other assessments, such as for iodine status analysis as in the Malawi and other national Demographic and Health Surveys.

Citation

Phiri, F. P., Ander, E. L., Lark, R. M., Bailey, E. H., Chilima, B., Gondwe, J., …Broadley, M. R. (2020). Urine selenium concentration is a useful biomarker for assessing population level selenium status. Environment International, 134, Article 105218. https://doi.org/10.1016/j.envint.2019.105218

• Journal Article Type: Article
• Acceptance Date: Sep 23, 2019
• Online Publication Date: Nov 9, 2019
• Publication Date: 2020-01
• Deposit Date: Nov 20, 2019
• Publicly Available Date: Nov 20, 2019
• Journal: Environment International
• Print ISSN: 0160-4120
• Electronic ISSN: 1873-6750
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 134
• Article Number: 105218
• DOI: https://doi.org/10.1016/j.envint.2019.105218
• Keywords: Biomarkers; Biomonitoring; Micronutrient survey; Selenium status; Sub Saharan Africa; Urine
• Public URL: https://nottingham-repository.worktribe.com/output/3292148
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0160412019323268
• Additional Information: This article is maintained by: Elsevier; Article Title: Urine selenium concentration is a useful biomarker for assessing population level selenium status; Journal Title: Environment International; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.envint.2019.105218; Content Type: article; Copyright: © 2019 The Authors. Published by Elsevier Ltd.