Quasim, TaraMcMillan, Donald C.Talwar, DineshVasilaki, KaterinaO'Reilly, Denis St J.Kinsella, John2022-03-302022-03-302005-07-28Quasim, T., McMillan, D.C., Talwar, D., Vasilaki, K., O'Reilly, D.S.J. and Kinsella, J. (2005) “The relationship between plasma and red cell B-vitamin concentrations in critically-ill patients”, 24(6), pp. 956-960.0261-5614https://doi.org/10.1016/j.clnu.2005.06.004https://eresearch.qmu.ac.uk/handle/20.500.12289/11969Item not available in this repository.Katerina Vasilaki – ORCID: 0000-0003-2669-5691 https://orcid.org/0000-0003-2669-5691Background and aims: Low vitamin B-complex status has been associated with poorer outcome in critically-ill patients. However, these findings have been based on indirect methods. Using direct methods for assessing vitamin status, we examined the effect of B-complex vitamin supplementation by measuring plasma and red blood cell B1, B2 and B6-vitamin concentrations in critically-ill patients. Methods: Thiamine diphosphate (TDP), flavin adenine dinucleotide (FAD) and pyridoxal phosphate (PLP) concentrations were measured in plasma and red cells of normal subjects (n ¼ 49) and ITU patients (n ¼ 41). Results: Compared with the normal subjects, critically-ill patients had higher C- reactive protein and lower albumin concentrations (Po0:001). Also, plasma FAD and PLP were lower (Po0:001) and red cell concentrations of both were higher (Po0:01) in critically-ill patients. Critically-ill patients were grouped according to whether (n ¼ 23) or not (n ¼ 18) they had been supplemented with B-complex vitamins. Compared with non-supplemented group, the supplemented group had significantly higher red cell TDP and PLP concentrations (Po0:01). Plasma FAD and PLP concentrations did not differ significantly between the groups. Conclusions: The results of the present study suggest that direct measurements of red cell FAD and PLP are more responsive to supplementation than plasma measurements in the critically-ill patient.956-960enB-vitaminsCritical IllnessC-reactive ProteinAlbuminPlasmaRed CellArticle