Postmenopausal bone remodelling and hormone replacement.

Abstract
Osteoporosis is a serious, frequently occurring disease. Sensitive, specific and precise biochemical measures of bone remodelling, thus, are important tools in the evaluation of bone loss, fracture risk and treatment response. Bone turnover is predictive of the subsequent rate of loss. A high bone turnover documented by increased levels of biochemical markers predicts an increased rate of loss in bone mass. Additionally, as a high bone turnover leads to an increase in the extent of bone resorption as well as an increase of the erosion depth, this may also cause deterioration of the bone structure, thereby leading to an increased risk of fracture. That the predictive values of bone mass and markers of bone turnover are additive suggests that these measures describe different properties of bone. Hormone replacement induces a reduction in postmenopausal bone turnover, arrests loss of bone mass and decreases fracture risk. The skeletal response to therapy is reflected by bone markers and these may be used for monitoring purposes. Those who are in most need of treatment can be identified by a combination of bone mass and bone marker measurement. Furthermore, those who need the treatment most will demonstrate the best response in terms of bone mass. Concern has arisen because of a relatively large day-to-day variation, especially in urinary markers; however, this seems to be resolved through use of the new serum markers.