The metal fingerprint of preeclampsia: evaluating the copper-to-zinc ratio in Nigerian pregnant mothers

Mathias A. Emokpae; Micheal . C Oyana; Irabonosa Asiriuwa; Loveth A. Emokpae; Nosakhare O.  Enaruna

doi:10.51496/jogm.v6.355

Authors

Mathias A. Emokpae Department of Medical Laboratory Science, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Nigeria
Micheal . C Oyana Department of Medical Laboratory Science, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Nigeria
Irabonosa Asiriuwa Department of Medical Laboratory Science, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Nigeria
Loveth A. Emokpae Department of Medical Laboratory Science, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Nigeria
Nosakhare O. Enaruna Department of Obstetrics and Gynaecology, School of Medicine, College of Medical Sciences, University of Benin, Benin City, Nigeria

DOI:

https://doi.org/10.51496/jogm.v6.355

Keywords:

preeclampsia, micronutrients, antioxidants, pregnancy, hypertension

Abstract

Background: Preeclampsia poses serious medical risks to pregnant women in the world, especially those in developing countries like Nigeria. This study aimed to identify specific levels of zinc, copper, and selenium and to determine the relationship between the copper-to-zinc ratio and preeclampsia in pregnant mothers.

Materials and Methods: Serum levels of zinc, copper, and selenium were analysed using atomic absorption spectrophotometry (AAS). The copper-to-zinc ratio was calculated, and a paired t-test was used to analyse the data; P-values less than 0.05 were considered statistically significant.

Results: Serum levels of zinc and selenium in pregnant women with preeclampsia were significantly lower (P < 0.001) than those of the normotensive pregnant women. Conversely, the serum copper level and copper-to-zinc ratio of pregnant women with preeclampsia were markedly higher (P < 0.001) when compared to those of the normotensive pregnant women. After adjusting for age and body mass index (BMI), the mean Cu/Zn ratio was 2.86 (95% confidence interval of 2.85–2.87, P < 0.01) and remained independently associated with pre-eclampsia in a multivariate regression. The Area Under the Receiver Operating Characteristic curve was excellent at 0.9.

Conclusion: The findings provide evidence of an imbalance in essential trace elements, resulting in a significantly elevated Cu/Zn ratio, which could serve as a metal fingerprint linked to preeclampsia in the examined group of Nigerian mothers. The finding is promising as a novel, cost-effective, and easily measurable biomarker for risk evaluation of preeclampsia in resource-limited settings.

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