title: New biochemical markers of bone resorption in the study of postmenopausal osteoporosis.
abstract: We performed a comparative study on the sensitivity of the determination of several biochemical markers of bone resorption: urinary calcium/creatinine, free pyridinolines (F-Pyr), free deoxypyridinoline (F-Dpyr), carboxyterminal telopeptide of collagen I (CTX) and aminoterminal crosslinked telopeptides of collagen I (NTX) in the study of postmenopausal osteoporosis. The study included 19 untreated osteoporotic postmenopausal women, aged 59 +/- 6 years, range 46-70 and 16 healthy control postmenopausal women, aged 56 +/- 7 years, range 48-70 years. The following bone markers were determined in 2-h fasting urine samples: calcium/creatinine (atomic absorptiometry), F-Pyr (ELISA, Metra), F-Dpyr (ELISA, Metra), CTX (Crosslaps, Cis bio International) and NTX (ELISA, Osteomark, OSTEX). Values of all markers were expressed as urinary creatinine (Cr) ratios. We found a significant increase in all the studied biochemical markers of bone resorption in osteoporotic patients with respect to control women. Areas under receiver operating characteristic (ROC) curves corresponding to F-Pyr/Cr, Calcium/ Cr, NTX/Cr, CTX/Cr and F-Dpyr/Cr were 74%, 75%, 93.4%, 95.7% and 96% respectively. There were no significant differences among the areas of the ROC curves corresponding to NTX, CTX and F-Dpyr, but areas under urinary calcium and F-Pyr were significantly lower. Among the biochemical markers of bone resorption studied, F-Dpyr, CTX and NTX presented the best discrimination between osteoporotic and control women. F-Dpyr/Cr sensitivity was 79% with a specificity of 100%, CTX/Cr sensitivity was also 79% with a specificity of 100% and NTX/Cr sensitivity was 52% with a specificity of 100%.
authors.affiliation: Laboratorio de Bioquímica, Fundación Jiménez Díaz, Madrid, Spain.
authors.forename: C
authors.initials: C
authors.lastname: de la Piedra
authors.forename: M L
authors.initials: ML
authors.lastname: Traba
authors.forename: C
authors.initials: C
authors.lastname: Dominguez Cabrera
authors.forename: M
authors.initials: M
authors.lastname: Sosa Henríquez
mesh_terms: D000368:Aged; D000375:Aging / Q000652:urine; D000596:Amino Acids / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D001862:Bone Resorption / Q000652:urine*; D002118:Calcium / Q000652:urine; D003094:Collagen / Q000652:urine*; D024042:Collagen Type I; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000652:urine*; D010455:Peptides / Q000652:urine*; D011725:Pyridines / Q000652:urine*; D012680:Sensitivity and Specificity
chemical_list: D000596:Amino Acids; D015415:Biomarkers; D024042:Collagen Type I; D010455:Peptides; D011725:Pyridines; C052929:collagen type I trimeric cross-linked peptide; C036020:deoxypyridinoline; D003094:Collagen; D003404:Creatinine; D002118:Calcium