[Biochemical markers of bone metabolism]

Markers of bone metabolism can be utilized for selection of treatment and/or evaluation of the treatment, and possibly decision-making to start treatment. Resorption markers are sensitive to detect changes in bone metabolism but show higher day-to-day variation, and formation markers are less sensitive but show less fluctuation. Among these markers, deoxypyridinoline, NTx, and CTx are utilized for short-term judgement of efficacy during the early phase of anti-resorptive treatment, such as bisphosphonate and hormone replacement therapy. The coefficients of day-by-day variations in these resorption markers are 8-14%. Thus, 20 (approximately 30)% or more change in marker levels may be necessary to detect the efficacy in individual patients on anti-resorptive therapy. The formation markers can be utilized for monitoring the degree of excessive suppression during the late phase of treatment by anti-resorptive treatment, possibly later than 6 months following initial treatment.