Monitoring antiosteoporotic treatment of postmenopausal women using biochemical markers of bone turnover.

Postmenopausal osteoporosis is preventable. An increasing number of antiresorptive therapies including estrogen, selective estrogen receptor modulators (the so-called designer estrogens), bisphosphonates and calcitonins are now available as treatment options for osteoporosis. These agents reduce the level of bone turnover and consequently slow or arrest bone loss and decrease the risk of fracture. However, these therapies are only effective if they are taken as prescribed. Unfortunately, most women who initiate antiresorptive therapy are unwilling or unable to make a long-term commitment to maintain such therapy. The test for biochemical markers of bone turnover can be used to confirm a biochemical response of bone within 3-6 months of initiating therapy, far sooner than the 2 years required for bone density testing. Such information incorporates a timely assessment of the woman's physiologic response with therapeutic compliance. A test result indicating the expected response to treatment may motivate some patients to remain compliant and maintain the therapy for an extended period of time. Bone turnover markers with demonstrated efficacy in monitoring the reduction of bone turnover induced by antiresorptive therapies include bone-specific alkaline phosphatase and osteocalcin (bone formation markers), and free deoxypyridinoline, N-telopeptide and C-telopeptide (bone resorption markers).