Nutrients (Apr 2023)

Reference Range of Vitamin K Evaluating Indicators in Chinese Childbearing Women

  • Shuhui Nie,
  • Lichen Yang,
  • Jie Feng,
  • Jiaxi Lu,
  • Huidi Zhang,
  • Weidong Li,
  • Yichun Hu,
  • Xiaoguang Yang

DOI
https://doi.org/10.3390/nu15081977
Journal volume & issue
Vol. 15, no. 8
p. 1977

Abstract

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Background: Vitamin K is an essential fat-soluble vitamin for the human body and its functions, such as promoting blood coagulation, bone health and preventing atherosclerosis, have attracted increasing attention. However, there is no recognized indicator and corresponding reference range for evaluating vitamin K status of different populations at present. The aim of this study is to establish a reference range for vitamin K evaluating indicators in healthy women of childbearing age in China. Methods: The population sample in this study was from the Chinese Adult Chronic Disease and Nutrition Surveillance (CACDNS) 2015–2017. A total of 631 healthy women of childbearing age (18–49 years) were included using a series of strict inclusion and exclusion criteria. The concentrations of VK1, MK-4 and MK-7 in serum were detected by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The other commonly-reported indicators evaluating vitamin K nutritional status, including undercarboxylated osteocalcin (ucOC), osteocalcin (OC), matrix Gla protein (MGP), desphosphorylated undercaboxylated MGP (dp-ucMGP) and protein induced by vitamin K absence II (PIVKA-II), were measured by enzyme-linked immunosorbent assay (ELISA). The reference range was obtained by calculating the 2.5% to 97.5% interval of the vitamin K evaluating indicators in the reference population. Results: The reference ranges of VK1, MK-4 and MK-7 in serum were 0.21–3.07 ng/mL, 0.02–0.24 ng/mL and 0.12–3.54 ng/mL, respectively. The reference ranges of ucOC, %ucOC, dp-ucMGP and PIVKA-II were 1.09–2.51 ng/mL, 5.80–22.78%, 2.69–5.88 ng/mL and 3.98–8.40 ng/mL, respectively. The cut-off values that can be used to evaluate subclinical vitamin K deficiency were as follows: VK1 2.51 ng/mL, %ucOC > 22.78%, dp-ucMGP > 5.88 ng/mL and PIVKA-II > 8.40 ng/mL. Conclusion: The reference range of VK1, MK-4, MK-7 and vitamin K-related indicators for healthy women of childbearing age established in this study could be used to assess the nutritional and health status of this population.

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