Measurements Of Osteocalcin And Cross-linked N-telopeptide Of Type 1 Collagen In Postmenopausal Osteoporosis And The Application Of Risedronate In Its Prevention And Treatment

Osteoporosis is a skeletal disorder characterized by compromised bone strength predisposing a person to an increase risk of fracture. Bone strength is determined by integrating bone mineral density(BMD) and bone quality. Postmenopausal osteoporosis is one of the most common metabolic diseases in old women. Biochemical markers of bone turnover included osteocalcin and cross-linked N-telopeptide of type 1 collagen can reflect the systemic bone dynamic change and bone turnover velocity. Futher more, they can be used to assess the effect of the anti-osteoporosis drugs.Part 1: The significance of measurement of osteocalcin and cross-linked N-telopeptide of type 1 collagen in postmenopausal osteoporosis. Objective: To investigate the significance of osteocalcin(BGP) and cross-linked N-telopeptide of type 1 collagen(NTx) in the postmenopausal osteoporosis. Methods: 382 women were enrolled and divided into 3 groups: pre-menopausal group, postmenopausal normal bone mass group and osteoporotic group according to the BMD result and whether they underwent menopause or not. BGP and NTx were measured by RIA and ELISA method.Results: BMD values in postmenopausal normal bone mass group and osteoporotic group were significantly lower than the pre-menopausal women( P <0.05),Serum BGP and uriary NTx values in the postmenopausal osteoporotic group weresignificantly higher than those in postmenopausal normal group,and the later has significant higher values than those in pre-menopausal women. Conclusion: Serum BGP and urinary NTx are the sensitive markers for the evaluation of the bone dynamic change and the prediction of the bone mass loss. Part 2: The study on the application of risedronate in the prevention and treatment of postmenopausal osteoporesisObjective: to determine the effects of risedronate on bone mineral density(BMD), as well as biochemical markers of bone turnover.Method: A total of 224 women aged 41 to 70 with osteopenia or osteoporosis were randomized to 5mg/d risedronate group and placebo group, in addition, all women received supplemental calcium and vitmine D for 12 months. BMD of lumber and hip were measured by DXA at beginning, the sixth month and the end of the study, biochemical markers of bone metabolism included BGP and ALP were determined before and after drug administration.Results: (1) The BMD at spine and proximal femur increased in the risedronate treated group compared with the control. The controls had an evident decrease at trochanter(P<0.01).(2) serum BGP and uriary NTx decreased 31.8% and 56.3% at the end of the study .compared with those at the beginning. Respectively,this was not found in control group.Significant differences were found in BGP and NTx between the two groups.Conclusion: This study confirms that risedronate exerts positive effects on the skeleton, increasing BMD and decreasing biochemical markers of bone turnover in postmenopausal women.