[Bone metabolic marker for osteoporosis].

The purposes hypothesized for the determination of bone metabolic markers, among which we can measure serum BAP, NTX, TRAP-5b or urinary NTX, DPD, CTX in routine clinical practice, are to predict the rate of bone loss and the resultant fracture risk, and to estimate bone quality. The higher value of bone markers, which might reflect high turnover bone disease, allows us to discriminate those who require early introduction of drug therapy such as bisphosphonate, and raloxifene. Furthermore, early reduction of bone resorption markers, but not bone formation markers, possibly 3-6 month after initiation of bone anti-resorptive drugs, enables us to predict bone gain thereafter. Among various bone resorption markers, TRAP-5b might be the best in that it is not susceptible to between-day variation, day-to-day variation, and renal dysfunction resulting from chronic kidney disease which often occurs in osteoporosis-prone elderly women.