[Biochemical markers of bone metabolism: clinical value in general practice]

Over the past years, the development of new biochemical markers of bone metabolism has generated a substantial amount of data about the pathogenesis, diagnosis, prevention and treatment of osteoporotic bone disease. When used in combination with clinical data and imaging techniques, these parameters permit a comprehensive and non-invasive evaluation of the skeletal status. Biochemical markers of bone metabolism may therefore be used to predict future bone loss and hip fractures in larger cohorts, to select therapy for individual patients, to predict the therapeutic response in individual patients, to monitor therapeutic response and efficacy in, and compliance of individual patients. As far as the initial clinical diagnosis of osteoporosis is concerned, none of the biochemical markers of bone turnover has proven useful as a single determination. Nevertheless, once the diagnosis of osteoporotic bone disease is made, biochemical markers of bone metabolism are useful tools in the further work-up, particularly in identifying patients with high rates of bone turnover. Furthermore, patients with high bone turnover appear to profit from anti-resorptive treatments more than subjects with low or normal bone metabolism. The measurement of bone turnover may therefore not only be useful in therapeutic decision making but can also help to reduce costs by identifying those individuals who may not respond well to treatment. Finally, bone markers are of clinical relevance in monitoring both the disease itself and therapeutic efficacy.