Bone Turnover Markers for Diagnosis of postmenopausal osteoporosis – A review

Postmenopausal osteoporosis is an age related skeletal metabolic disorder that affects most elderly women worldwide owing to the loss of estrogen activity, increase in bone turnover rate and circulating level of bone turnover markers. Although osteocalcin, bone specific alkaline phosphatase, and pro-collagen type I N- and C-terminal pro-peptides are considered as the most sensitive markers of bone formation however, they suffer some limitations. Consequently, periostin, sclerostin and dickkopf-1 protein (Dkk-1) are emerging diagnosis markers of bone pathologies and monitoring therapeutic interventions and management of postmenopausal osteoporosis. These markers serve as effective tools for diagnosis of bone disorders, predict reduction in fracture risk, reflect metabolic effect of drugs during bone remodeling and could be used to establish the lowest dose that elicit the required change in bone mineral density. Biological variability from different sources including controllable and uncontrollable factors could serve as the major limitations of these established markers of bone formation (BFMs). This review, therefore focus on the therapeutic applications of selected bone turnover markers for early diagnosis of postmenopausal osteoporosis.