Biomarkers of bone health and osteoporosis risk.
The assay features of biochemical markers of bone turnover have markedly improved in the past few years. The most sensitive and specific markers of bone formation include serum bone alkaline phosphatase, total osteocalcin (including the intact molecule and the large N-mid fragment) and the procollagen type I N-terminal propeptide assay. Among the various markers of bone resorption, measurements of the urinary excretion of N- and C-terminal cross-linked telopeptides) and of serum C-terminal cross-linked telopeptides are the most sensitive and specific. Markers of bone turnover can be used to predict the rate of bone loss in post-menopausal women and can also be used to assess the risk of fractures. In osteoporosis-treatment studies (with alendronate, risedronate, raloxifene) markers of bone turnover appear even more strongly associated with fracture risk reduction than bone mineral density (BMD). These observations support the use of markers of bone turnover as surrogates for fracture risk reduction, perhaps even more so than BMD. Bone markers can also be used to monitor the efficacy of antiresorptive therapy such as hormone-replacement therapy, raloxifene and bisphosphonates in individual patients. Furthermore, they have also proved to be helpful in monitoring the response to nutritional interventions and have the advantage over BMD in that they provide information about mechanism of effect and changes are often observed much more rapidly.
Eastell
Richard
R
Academic Unit of Bone Metabolism, University of Sheffield, Metabolic Bone Centre, Sorby Wing, Northern General Hospital, Herries Road, Sheffield S5 7AU, UK. r.eastell@sheffield.ac.uk
Hannon
Rosemary A
RA
D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D016723:Bone Remodeling / Q000187:drug effects / Q000502:physiology; D001842:Bone and Bones / Q000378:metabolism*; D003094:Collagen / Q000097:blood; D005260:Female; D050723:Fractures, Bone / Q000453:epidemiology*; D006801:Humans; D015675:Osteocalcin / Q000097:blood; D015663:Osteoporosis, Postmenopausal / Q000097:blood* / Q000188:drug therapy; D017063:Outcome Assessment, Health Care; D012307:Risk Factors
D015415:Biomarkers; D050071:Bone Density Conservation Agents; D015675:Osteocalcin; D003094:Collagen; D000469:Alkaline Phosphatase