Forum Diagnosticum No.03/2013
The Bone Turnover Markers and Their Application in Osteoporosis Management
The quantitative measurement of the bone mineral density (BMD) is highly necessary in the clinical evaluation of the osteoporosis patients. Yet, BMD is a static parameter unable to provide information about the rate of born turnover. On the contrary, the bone remodeling biochemical markers have dynamic characteristics and provide a comprehensive bone analysis. The measurement of BMD can provide useful information, yet with a down side: the detected bone density difference just shows significant changes 1 or 2 years upon the therapy. Moreover, the compliance with the medication is a common problem exhibited by osteoporosis patients as with the other chronic asymptomatic diseases in addition to those undetected by the BMD measurement.
Therefore, the role that Bone Turnover Markers (BTMs) play for osteoporosis patient management is really crucial. The signs of BTMs contribute to providing the better bone physiological comprehension and metabolic bone disease pathogenesis. Although it is not suitable for osteoporosis diagnosis, BTMs can provide additional information and complement the BMD information. BTMs contribute the useful data to determine the optimum medication dosage for the patient in 3-6 months, compared to a period of 1-2 years needed with the bone mineral density application. BTMs are beneficial in monitoring the efficacy of the osteoporosis therapy along with its response, confirming the compliance with the therapy, selection of the patients for the therapy, and predicting the risk factors. Nevertheless, it is important to consider the analytic and preanalytic variabilities in order to acquire the accurate interpretation.
The standard adoption of the international reference will highly increase the laboratory consistency and facilitate the inclusion of such markers into the clinical treatment. Further studies are recommended to determine the optimum monitoring protocol toward the different medications, including the optimum medication targets for the standard references of BTMs, namely s-P1NP and s-CTx. This assessment measurement standardization will be helpful in universally determining the cut off and targets to have them included in the guideline. Conclusively, BTMs become the better surrogate markers, while their connection with the BMD measurement gives better information on the bone status.
Author: Emmy F. Harefa (PT Prodia Widyahusada)