The use of biochemical markers of bone turnover in the clinical management of primary and secondary osteoporosis.

The purpose of the present study was to examine of the current role of bone turnover markers (BTMs) in the management of osteoporosis. Perusal of the literature examines the available evidence for the utility of BTMs for decision to treat and for the monitoring of treatment for osteoporosis. There is no evidence for the use of BTMs for fracture risk calculation, decision to treat or for treatment selection. A very abnormal BTM value may be a clue to the presence of bone pathology other than uncomplicated osteoporosis. Whilst changes to BTMs following various osteoporosis treatments are well defined, their utility in monitoring individual patients has been less well established. Some fracture outcome-based data exist for the use of u-NTX target of <21 nmol BCE/mmol for antiresorptive therapy; the equivalent s-CTX level is ~250 ng/L. Suboptimal BTM response to treatment may indicate non-compliance or the presence of secondary causes of osteoporosis which may need addressing. Studies are needed to establish treatment targets based on fracture outcomes for commonly used BTMs for each established osteoporosis therapy.