Context: Bone turnover markers (BTMs) may identify changes in bone remodeling within a relatively short time interval before changes in bone mineral density can be detected. New markers such as osteoprotegerin, receptor activator of nuclear factor-B ligand, and sclerostin have emerged, but there is little information about their potential use in clinical practice.
Design, Patients, and Setting: We performed an observational prospective study in pre-and postmenopausal ambulatory women (n =72 and n =152, respectively).
Intervention: Postmenopausal women with osteoporosis (n =18) were treated with risedronate and calcium. Womenfilled out a questionnaire and underwent bone mineral density measurement using dual-energy x-ray absorptiometry at the time of enrollment and after 1 year of follow-up. BTMs were measured at baseline, at 6 months, and after 1 year.
Results: Increased levels of N-terminal propeptide of type 1 procollagen (P1NP) and beta-type I collagen telopeptides (CTXs) were associated with low bone mineral density in the premenopausal (P =.02 and P =.04, respectively) and postmenopausal (P =.03 and P =.02) groups. The best analytical performance to diagnose osteoporosis was for = -CTX, osteocalcin, and P1NP, with areas under the curve of 0.70 (P =.005), 0.64 (P =.048), and 0.71 (P =.003). A significant decrease was found in P1NP, osteocalcin, tartrate-resistant acid phosphatase-5b, =-CTX, and bone alkaline phosphatase after 1 year of treatment (all P =.05).
Conclusions: Our data suggest that measurement of beta beta-CTX and P1NP shows adequate analytical performance and could potentially be included in algorithms for the screening of osteoporosis. Furthermore, these two markers, along with osteocalcin and tartrate-resistant acid phosphatase5b, are useful to monitor the response to risedronate.