The molar ratio of retinol-binding protein to transthyretin in the assessment of vitamin A status in adults. Proposal of a cut-off point.
Clin Chem Lab Med
; 40(12): 1301-7, 2002 Dec.
Article
em En
| MEDLINE
| ID: mdl-12553434
ABSTRACT
The molar ratio of retinol-binding protein to transthyretin (RBPTTR) has been proposed as an indirect method to assess vitamin A status in children with inflammation. Neither reference values nor appropriate cut-off point are available for adults. RBP, TTR and retinol were determined in plasma from 100 healthy adults and 31 low-risk surgical patients with no inflammatory response. RBPTTR percentile distribution from 99 healthy adults with plasma retinol > or = 0.7 micromol/l was 2.5th = 0.24; 5th = 0.31; 10th = 0.32; 25th = 0.41; 50th = 0.47; 75th = 0.54; 90th = 0.67; 95th = 0.78 and 97.5th = 0.81. In order to define a cut-off point, receiver operating characteristic (ROC) curve was constructed, using plasma retinol as gold standard. ROC curve was based on data from the 131 studied subjects, 11 of whom (8.4%) were classified as deficient on the basis of plasma retinol < 0.7 pmol/l. According to ROC curve criteria, RBPTTR ratio was considered a good test, the area under the curve being 0.822, p < 0.001. A cut-off-point of < or = 0.37 is proposed to detect vitamin A deficiency in adults, since it allows reaching high sensitivity (81.8%), specificity (79.2%) and predictive value (79.4%). The proposed cut-off point falls between 13th and 14th percentiles.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vitamina A
/
Deficiência de Vitamina A
/
Pré-Albumina
/
Proteínas de Ligação ao Retinol
Tipo de estudo:
Prognostic_studies
Limite:
Adolescent
/
Adult
/
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article