In:
British Journal of Nutrition, Cambridge University Press (CUP), Vol. 119, No. 6 ( 2018-03-28), p. 629-635
Kurzfassung:
The prevalence of a sub-clinical vitamin B 12 deficiency in the vegetarians is high. Total serum vitamin B 12 concentration alone does not reliably reflect vitamin B 12 status. Holotranscobalamin (holo-TC) II is a bioactive B 12 fraction promoting specific uptake of B 12 by cells and the circulating concentration reflects the intake of B 12 , whereas total homocysteine (tHcy) indicates the metabolic ability. In this study, we investigated the diagnostic value of circulating holo-TC, B 12 , folate and homocysteine in vegetarians who were at risk of B 12 deficiency. B 12 -related biomarkers were measured in 119 young, healthy graduate vegetarians. None was folate deficient. As per reported definition, half were B 12 deficient; 70 % of males and 50 % of females had low plasma holo-TC concentrations; and 92 % of males and half of females had hyperhomocysteinaemia. None had any clinical signs of B 12 deficiency. Receiver operating characteristic curve analysis demonstrated similar AUC at the B 12 concentration of 100 and 150 pmol/l when holo-TC (0·777 and 0·784) and homocysteine (0·924 and 0·928) were used as variables. Cut-off value of 100 pmol/l resulted in the highest sensitivity of 77·78 % and specificity of 71·05 % with a predictive value of 19·6 pmol/l for holo-TC and a sensitivity of 82·72 % and specificity of 89·7 % with a predictive value of 21·7 µmol/l for homocysteine. The combination of B 12 , holo-TC and tHcy improves the diagnostic accuracy at these cut-offs, and we suggest that for the young Indian vegetarians the cut-off for plasma B 12 and holotrancobalamin is 100 pmol/l and 19·6 pmol/l, respectively, and for homocysteine it is 17·6 (females) and 27 µmol/l (males) for identifying B 12 deficiency.
Materialart:
Online-Ressource
ISSN:
0007-1145
,
1475-2662
DOI:
10.1017/S0007114518000090
Sprache:
Englisch
Verlag:
Cambridge University Press (CUP)
Publikationsdatum:
2018
ZDB Id:
2016047-1
SSG:
12
SSG:
21
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