Skip to main content

Vitamin D status in critically ill patients: back to basics!


No abstract

The problem of vitamin D deficiency during intensive care requires a number of clarifications. Initially, it is essential to focus on the fundamentals of vitamin D status assessment. Total 25-hydroxyvitamin D (25OH-D) is currently considered as the best indicator of vitamin D status. Due to practical reasons (less knowledge needed, higher throughput), immunoassays are generally preferred to measure serum 25OH-D levels. In the critical care context, however, they may be biased due to matrix effects [1]. During the acute phase of critical care, these assays should then be abandoned in favor of liquid chromatography-tandem mass spectrometry. Moreover, standardization of vitamin D assays is crucial: such a process is ongoing worldwide but, to date, is still incomplete. It is important to note that both points are rarely considered in the published studies related to vitamin D in critically ill patients: the data may thus be interpreted with caution.

The bioavailable and free fraction of 25OH-D are attractive complementary markers of vitamin D status; however, progress is needed before establishing their evidence [2]. We need an accurate assay rather than formulas to measure free and bioavailable concentrations. We also need to determine normal or optimal ranges and to investigate their clinical impact. In the future, it seems important to consider these analytical prerequisites when studying vitamin D in critically ill patients. Meanwhile, these patients should benefit from the potential beneficial effects of vitamin D. Cholecalciferol is, in fact, a cheap medication with a wide therapeutic window. We believe that the critically ill should be supplemented with vitamin D as they are clearly at risk of deficiency. Meanwhile, for specific protocols, intensivists should at least follow the Endocrine Society guidelines [3],[4].



25-hydroxyvitamin D


  1. Rousseau AF, Damas P, Janssens M, Kalin S, Ledoux D, Le Goff C, Gadisseur R, Delanaye P, Cavalier E: Critical care and vitamin D status assessment: what about immunoassays and calculated free 25OH-D?. Clin Chim Acta. 2014, 437: 43-47. 10.1016/j.cca.2014.07.007.

    Article  CAS  Google Scholar 

  2. De Pascale G, Quraishi SA: Vitamin D status in critically ill patients: the evidence is now available!. Crit Care. 2014, 18: 449-10.1186/cc13975.

    Article  Google Scholar 

  3. Heaney RP, Holick MF: Why the IOM recommendations for vitamin D are deficient. J Bone Miner Res. 2011, 26: 455-457. 10.1002/jbmr.328.

    Article  CAS  Google Scholar 

  4. Holick MF, Binkley NC, Bischoff-Ferrari HA, Gordon CM, Hanley DA, Heaney RP, Murad MH, Weaver CM: Evaluation, treatment, and prevention of vitamin D deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011, 96: 1911-1930. 10.1210/jc.2011-0385.

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Anne-Françoise Rousseau.

Additional information

Competing interests

The authors declare that they have no competing interests.

Rights and permissions

This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Rousseau, AF., Cavalier, E. Vitamin D status in critically ill patients: back to basics!. Crit Care 18, 611 (2014).

Download citation

  • Published:

  • DOI: